Äîêóìåíò âçÿò èç êýøà ïîèñêîâîé ìàøèíû. Àäðåñ îðèãèíàëüíîãî äîêóìåíòà : http://www.fadr.msu.ru/inqua/Reno.doc Äàòà èçìåíåíèÿ: Thu Feb 5 12:50:58 2004 Äàòà èíäåêñèðîâàíèÿ: Mon Oct 1 19:39:02 2012 Êîäèðîâêà: Ïîèñêîâûå ñëîâà: local bubble

RE-INTERPRETATION OF NORTHERN GREAT BASIN PALEOSOLS
KLEBER, Arno
Chair of Physical Geography/Regional Geography of Central Europe, Institute
of Geography, TU Dresden, Dresden 01062 Germany, arno.kleber@mailbox.tu-
dresden.de.

Fossil soils between lake deposits of the last two deep-lake cycles in the
northern Great Basin have multiple carbonate-engulfed horizons, and
compound calcic and argillic properties at depth. They are difficult to
explain pedogenetically because they bifurcate in places, especially in
basin centres where they appear separated by sediments of a minor lake
expansion of probable early Wisconsinan age. A sequence of processes may
account for all observed phenomena: two cycles of colluviation and
synchronous admixture of carbonate-bearing loess particles were each
succeeded by the formation of an argillic over a calcic horizon. The first
of these cycles started at the end of oxygen isotope stage 6, the second
one around the transition between stages 4 and 3. Carbonate enrichment
resulting from the later soil formation often affected the older, buried
soil. This led to welding of the two soils and the formation of a compound
horizon carrying the argillic properties of the first and the calcic
properties of the second pedogenic phase. Steady eolian influx to the same,
former soil surface, a commonly invoked mechanism, cannot explain the
bifurcated palaeosols and is not needed to explain the welded ones. One
important implication of these findings is that paleosols in this area may
bear information on paleoclimate to a greater extent than, or even in
contrast to, previous interpretations. On surfaces, which were not covered
by lakes at 13ka B.P., a relict soil of intermediate maturity has developed
in another loess-mixed colluvial layer. At paleolake margins the three
different deposits and soils merge into one multilayered soil profile with
disconformities still representing the stratigraphic borders. These may be
traced into mountains surrounding the Great Basin.

ORIGINS OF CALCRETE DEVELOPED ON PRECAMBRIAN SILICATE ROCKS USING SR
ISOTOPIC TRACING AND MICROMORPHOLOGICAL ANALYSIS: IMPLICATIONS FOR CLIMATE
CHANGE IN THE SEMI-ARID INTERIOR OF SOUTH INDIA
DURAND, Nicolas L.1, GUNNELL, Yanni2, CURMI, Pierre1, HAMELIN, Bruno3, and
AHMAD, Masood S.4
(1) Ecology, French Institute of Pondicherry, 11, Saint Louis Street,
Pondicherry, 605001, India, nicolas.durand@ifpindia.org, (2) Department of
Geography, UniversitÈ Denis-Diderot (Paris 7), and Laboratoire de
GÈographie Physique, CNRS-UMR 8591, 1 Place A. Briand, Meudon, 92120,
France, gunnell@paris7.jussieu.fr, (3) CEREGE, EuropÒle MÈditerranÈen de
l'Arbois, B.P. 80, Aix-en-Provence, 13545, France, (4) National Geophysical
Research Institute, Uppal Road, Hyderabad, 500 007, India

This study associates micromorphological analysis and isotopic tracing of
the various calcrete occurrences on basement rock outcrops in South India,
in order to understand their formation and evolution, and assess their
value as indicators of paleoclimatic change. The two main settings are
upland Karnataka (ca. 900 m) and lowland Tamil Nadu (ca. 400 m),
respectively. Toposequences and vertical profiles were described and
sampled for measuring the isotopic composition of specific phases of
carbonates, including susceptible bedrock sources of calcium. 87Sr/86Sr
ratios are specific to different marine and terrestrial reservoirs and
materials and are not modified by dissolution and precipitation processes.
Sr concentrations and isotopic compositions were determined by thermal
ionization mass spectrometry (TIMS). Results on carefully targeted fabric
sub-units identified in thin section have given Sr isotopic ratios of
0.709218 and 0.709383 for laminar calcrete capping elevated parts of the
lowland landscape in Tamil Nadu. These values are close to ratios known for
Quaternary sea water (0.7092), implying advection of Ca-rich dust from
exundated carbonate platforms during low sea stands. For sites in upland
Karnataka (calcic soil horizon and colluvial lag, respectively) Sr ratios
of 0.711237 were obtained. Such a value is closer to those observed for
silicate bedrock, and suggests near-field Ca transfer by water through
slope wash processes.We therefore reveal three categories of calcrete
deposit: (1) where no local commanding relief exists (Palghat Gap),
outcropping groundwater paleocalcrete is shown to also incorporate far-
field aeolian Ca. (2) Near-field Ca provenance dominates in the upland
sites that are more remote from India's shorelines and where a commanding
bedrock landform has supplied solutes with no detectable aeolian input. (3)
In situ Ca accumulation by primary pedogenesis is variable and difficult to
quantify at any given site exhibiting pedogenic carbonates. Based on the
diversity of (1) formative hydrological settings, (2) provenances of
calcium, and (3) fabric transformations, most calcrete occurrences thus
appear to be hybrid, polygenetic and partly relict, but indicative of
fairly stable semi-arid climatic conditions in the rainshadow of the
Western Ghats at the 100 ky time scale.

EUREKA FLAT: A LONG-TERM DUST-PRODUCTION ENGINE OF THE PALOUSE LOESS,
PACIFIC NORTHWEST, USA
SWEENEY, Mark R.1, GAYLORD, David R.1, BUSACCA, Alan J.2, and HALVER,
Brandt A.1
(1) Dept. of Geology, Washington State Univ, Pullman, WA 99164-2812,
sweeney@wsunix.wsu.edu, (2) Dept. of Crop and Soil Sciences, Washington
State Univ, Pullman, WA 99164-6420

Thick and expansive loess accumulations require long-term sources of dust
and relatively stable climatic conditions as demonstrated by deposits of
the Palouse loess in the U.S. Pacific Northwest. Eureka Flat, a narrow, 80-
km-long deflationary plain oriented parallel to prevailing southwesterly
winds, has been a source of Palouse loess throughout the Pleistocene.
During this time, episodic glacial outburst floods have replenished the
supply of fine-grained sediment that mantles Eureka Flat.Wallula Gap, a
bedrock canyon incised by the Columbia River, funnels the prevailing winds
that flow across Eureka Flat. These winds have persistently re-entrained
sand, silt, and clay-rich flood sediment into sand dunes, sand sheets, and
downwind loess. The upwind margin of Eureka Flat contains actively
deflating fine-grained outburst flood deposits that are discontinuously
capped by stabilized to partially stabilized parabolic dunes, sand sheets,
and thin sandy loess. The central to downwind margin of Eureka Flat is
devoid of dunes and is blanketed by 1.5 m of post-last glacial maximum
(LGM) loess. Coring at the downwind end of Eureka Flat has revealed an
extensive sand sheet buried by loess. The sand sheet to loess transition is
characterized by a gradual change from unimodal, stratified eolian sand, to
structureless, bimodal eolian sand and silt with insect burrows and
rhizoliths, to unimodal, sandy loess. This stratigraphy marks a
bioclimatically driven change from arid eolian sand deposition to less arid
loess deposition as the density of dust-trapping vegetation increased. Up
to 4.5 m of post-LGM sandy loess mantles topography adjacent to and
downwind from Eureka Flat as linear ridges aligned parallel to the
prevailing wind. These linear loess ridges occur immediately downwind from
dust-producing basins and apparently extend in the wind shadows of
topographic obstacles, including basalt knobs. Loess isopach maps reveal a
relatively thick finger of loess that extends directly downwind of Eureka
Flat for approximately 150 km. Up-building of loess on this finger-shaped
accumulation has continued through much of the past 75 ka, illustrating the
profound influence of the Eureka Flat dust engine.

SOM- AND BONE-DERIVED ISOTOPIC SIGNALS AS PROXIES OF LATE PLEISTOCENE AND
HOLOCENE CLIMATIC CONDITIONS IN THE CENTRAL GREAT PLAINS, U.S.A
JOHNSON, William C., WILLEY, Karen L., CAMPBELL, Joshua S., and ROBINSON,
Julie R.
Geography, Univ of Kansas, 1475 Jayhawk Blvd Rm 213, Lawrence, KS 66045-
7613, wcj@ku.edu

In recent years, a record of climatic prehistory for the central Great
Plains (Kansas, Nebraska, eastern Colorado) has begun to emerge. Stable
isotope ratio analysis (SIRA) of carbon has proven to be particularly
useful in determining the flora and fauna, and hence climate for the Late
Pleistocene and Holocene. SIRA was conducted on (1) soil organic matter
(SOM) of modern and E S D A Y buried soils, and (2) bone of modern and
prehistoric prairie dogs (Cynomys sp.) and ground squirrel (Spermophilus
sp.). SIRA of carbon on modern soil and bone material provides the
necessary baseline data for contemporary climatic patterns and reflects the
regional westward decrease in moisture and attendant change in grass carbon
pathways (C3-C4 shift). To appreciate the local/topographic variability
inherent in isotopic values from modern soils, a 0.6km grid was sampled in
near-pristine prairie at the Konza Prairie, a Long Term Ecological Research
Area. The prehistoric record was extracted from two major soils developed
and preserved throughout the region, the Gilman Canyon Formation soil (c.
35-20 ka) and the Brady soil (c. 11-9 ka), as well as from the associated
Peoria and Bignell loesses. The prehistoric isotopic sequences reveal
periods of both gradual and abrupt environmental change, and highlight the
nature of the Pleistocene- Holocene boundary.


PALEOENVIRONMENTAL INFERENCES FROM .13C OF SOIL ORGANIC CARBON IN 14C-DATED
PROFILES IN THE U.S. GREAT PLAINS
FOLLETT, Ronald F.1, LEAVITT, Steven W.2, KIMBALL, John M.3, and PRUESSNER,
Elizabeth G.1
(1) Soil Plant Nutrient Research, U.S. Dept. of Agriculture - ARS, 301 S.
Howes, Room 407, Ft. Collins, CO 80522, rfollett@lamar.colostate.edu, (2)
Lab. of Tree- Ring Research, Univ of Arizona, 105 W. Stadium, Bldg. #58,
Tucson, AZ 85721, sleavitt@ltrr.arizona.edu, (3) NSSC Survey Center,
USDA/NRCS, Federal Building, Room 152 - Mail Stop 34, 100 Centennial Mall
North, Lincoln, NE 68508-3866

The historic grasslands of North America stretch from Texas to North Dakota
within the United States, and are a principal agricultural small grain-
producing region over the last Century, i.e., America's "breadbasket".
Across this region, areas of original grassland still exist, undisturbed by
plowing and cultivation, which offer us profiles developed in response to
the plant cover and climate of the past several thousand years.We sampled
14 of these native grassland sites over a wide area extending over 13œ of
latitude and 10œ of longitude. After removal of soil carbonates, we
obtained radiocarbon ages on soil organic carbon (SOC) by soil profile
horizon (ranging from 5 to 40 cm in thickness) to an average depth of 1.9±
0.3 m and analyzed the stable-carbon isotope composition (.13C) of each of
these samples. In most cases, SOC in surface soils is modern or post-bomb
with respect to radiocarbon content, and the corresponding .13C is highly
correlated to the .13C signature of live vegetation at the site. Usually
radiocarbon age of SOC increased with depth, in some cases with ages below
1.5 m in excess of 10,000 years, although occasionally a reversal occurred
perhaps related to erosion-deposition effects and paleodrainage. The SOC
.13C generally became more negative with depth.We have examined the
patterns of .13C variation with depth (age) to infer changes in proportions
of past C3 and C4 vegetation, which can shift in response to past climate
conditions. A warming climate is probably indicated from ~12,000 yBP to
~2000 yBP.

STABLE ISOTOPIC COMPOSITION OF PEDOGENIC CARBONATES FROM THE EASTERN MARGIN
OF THE THAR DESERT, RAJASTHAN, INDIA
ACHYUTHAN, Hema1, QUADE, Jay2, ROE, Lois2, PLACZEK, Christa2
(1) Centre for Geoscience and Engineering, Anna University, Sardar Patel
Road, Chennai, 600 025, India, achuthan@giasmd01.vsnl.net.in, (2)
Department of Geosciences, Univ of Arizona, Tucson, AZ 85721

Pedogenic carbonates in a 19m-thick dune section (16R) at Didwana, and
several shorter profiles from the eastern margin of the Thar Desert,
Rajasthan, were studied for their stable isotope composition. Carbon
isotope results show the C4 biomass (grasses?) has dominated local
vegetation for most of the 250,000 years represented by the 16R section.
Our results display a decrease in . 18O and . 13C values during the last
interglacial and early glacial periods. The higher . 13C values in our dune
records correlate to episodes in the strong upwelling and decreased
sedimentation rates in Indian Ocean cores, probably the result of a strong
Asian Monsoon. The high . 13C values may therefore denote the expansion of
C4 vegetation in response to warm, wetter monsoon circulation. Conversely,
low . 18O and . 13C values mark the expansion of C3 vegetation, probably
caused by stronger winter rains and lower temperatures.

POLYPHASE DUNE AND SOIL FORMATION ON THE MAPUTALAND COASTAL PLAIN
BOTHA, Greg A.1,PORAT, Naomi2
(1) KwaZulu-Natal Unit, Council for Geoscience, P.O. Box 900,
Pietermaritzburg, 3200, South Africa, gabotha@mweb.co.za, (2) Geol Survey
of Israel, 30 Malkhe Israel St, Jerusalem, 95501, Israel

Maputaland forms the southern end of the East African coastal plain. Dunes
have accumulated since the Neogene and the general coast-parallel
arrangement of dune systems stabilised by grassland and forest has been
assumed by previous researchers to young coastward. Detailed mapping of the
dune morphology revealed that composite parabolic and hummocky dune systems
represent polyphase aeolian reworking. The project assessed relative- and
numeric dating techniques that can be used to differentiate dune systems.
Soil profile characteristics were used to calculate soil development
indices (SDI) for sampled horizons from holes hand augered to 6m
depth.Weathering indices were calculated from geochemical data, magnetic
susceptibility was measured and infrared stimulated luminescence dating of
representative dune sands defined the period of pedogenesis since
deposition. The quartzose dune sands have weathered to form deep reddened
soil profiles with higher SDI horizon values reflecting pH decrease,
advanced rubification, clay increase and harder consistency down profile.
The Holocene profiles exhibit decreasing horizon index values below the
Ahorizon whereas late Pleistocene profiles display downward increasing
horizon index values within the upper 3m of the profile. Greater complexity
and horizonation within some mid- to late Pleistocene aeolian sands
manifests as distinctly mottled, clay-enriched horizons at depths of 2- 5m
below the surface. The SDI profiles from specific dune systems or
stratigraphic units cluster well and effectively contrast the
characteristic soil development on dunes of different ages. Plots of
depositional age vs. sampled horizon index values enable the derivation of
generalised rates of soil profile development and comparison of pedogenic
processes on the high rainfall coastal barrier dunes relative to the drier
interior. SDI horizon values distinguish composite profiles and highlight
possible localised surficial reworking or profile burial. The technique is
less effective in differentiating profiles where longer-term accretion
occurred on a dune. When plotted against geochemical weathering index
values or magnetic susceptibility, the SDI methodology proved effective in
differentiating dune sands or provenances. management scenarios. PEATLAND
includes CO2 and CH4 production from different soil organic matter
reservoirs, including the peat substrate of the soil. CO2 production is
modelled using first order decomposition rates. The decomposition constants
are influenced by the environmental factors temperature, soil aeration,
soil moisture and pH. The CH4 emission includes production from fresh
organic matter, methane oxidation in the soil, and transport by diffusion,
through plant roots and bubbles. Both submodels are linked to a primary
production model. The model is validated using closed chamber flux
measurements at three sites in the Netherlands. The model results indicate
interesting links between CO2 and CH4 production in cases of a seasonally
fluctuating water table. The CH4 production during high water table periods
is suppressed by aerobic decomposition of fresh organic matter reservoirs
during low water table periods. In case of a winter-high, summer-low water
table regime CH4 flux peaks occur in spring and autumn. High CH4 emission
only occurs after a considerable raise of the water table. In some cases
this may cause a net increase of the greenhouse gas flux (expressed in CO2
equivalents) in spite of a decreased CO2 flux.

PEDOGENETIC IMPACT OF VOLCANISM ON THE HOLOCENE PALEOSOLS OF KAMCHATKA
PENINSULA
MAKEEV, Alexander O.1, ALYABINA, Irina O.1, BRAITSEVA, Olga A.2,
ZAHARIHINA, Lalita V.3, KARPACHEVSKI, Lev O.4, SHOBA, Sergei A.4, and
MARECHEK, Maria S.4,
(1) Soil Institute, Moscow State Univ, Vorobyovy Goru, Moscow, 119899,
Russia, makeev@fadr.msu.ru, (2) Institute of Volcanic Geology and
Geochemistry, Russian Academy of Sciences, Piip Blvd 9, Petropavlovsk-
Kamchatski, 683006, Russia, (3) Sci- Rsch geotechnological Ctr of the Far-
East branch of Russian Academy of Sciences, North- East avenue, 30,
Petropavlovsk-Kamchatski, 683006, Russia, (4) Soil Science Faculty, Moscow
State Univ, Vorobyovy Goru, Moscow, 119899

Kamchatka peninsula is characterized by long-distance marker layers of
tephra as a result of the largest explosive eruptions during the Holocene.
Due to a combination of cold climate and comparatively young age tephra
layers are not deeply transformed by weathering. This, together with low
bioturbation intensity, results in a sequence of clearly visible horizontal
layers, retaining their morphological, chemical and mineralogical identity.
These marker layers are interstratified with buried soil profiles, making
it possible to study transformation of tephra material within the soil
profile under various climatic conditions though the whole Holocene. Soils
of Kamchatka, formed on volcanic ashes were studied with consideration of
extensive set on radiocarbon dating and constitution of tephra-paleosol
sequences. The soils have been formed under various bioclimatic conditions,
including the main types of vegetation of Central and Western Kamchatka
(tundra, taiga, mountain meadows, etc.). The age of present day surfaces in
the study area differs from tens of years to 1760 years before present. The
vegetation type mostly determines modern features of volcanic soils. These
allow using surface organic horizons as diagnostic. Constitution of soil
profile is strictly determined by constitution of tephra-paleosol sequence.
A set of buried soil horizons within the time span of 8000 years before
present was studied. The degree of both physical and chemical weathering
increases with tephra age. Tephra marker horizons have been compared within
buried soil profiles and adjacent bogs, showing less advanced weathering
under the thick layer of peat. The study of constitution and spatial
distribution of tephra-paleosol sequences allows determining
tephrostratotype as a steady sequence of tephra marker horizons. GIS
approach allows to present cartographic images of tephrostratotypes for any
given point within the study area, based on combination of marker horizons
of 29 largest explosive Holocene eruptions.

PALEOSOLS IN ARID LANDS. POLYCYCLIC PEDOGENESIS ON THE MESSAK PLATEAU
(FEZZAN - LIBYAN SAHARA)
TROMBINO, Luca, CREMASCHI, Mauro, and ZERBONI, Andrea
Earth Sciences Department, Univ of Milano, Via Mangiagalli 34, Milano, I
20133, Italy, Luca.Trombino@unimi.it

The Messak Sattafet is a wide plateau cut in Cretaceous sandstone,
interpreted as relict of a Tertiary peneplain, heavily affected by fluvial
dissection and aeolian deflation. Notwithstanding this, discontinuous soil
bodies are locally persevered below the stony desert pavement. The
paleosols represented by these pedological remains were generated by soil
forming processes as clay illuviation, rubification, gilgai microrelief
formation, which acted during different periods of the Quaternary and were
interrupted by several erosional phases and episodes of aeolian input.
Radiocarbon and U/Th datings and archaeological material content allow to
date the soil forming phases (in a wet environment) and alternating
desertification periods since the Middle Pleistocene up to the Holocene.
Relationships between paleopedogenesis and climatic changes is assessed on
the base of field evidence, routine analyses and micromorphology.

PALEO)PEDOLOGICAL SURVEY ON OLD TERRACES IN NORTH-WEST ITALY (VAL SESIA)
TROMBINO, Luca1, PETRELLA, Fabio2, IARICCI, Marcella1, and PONTI, Ilaria1
(1) Earth Sciences Department, Univ of Milano, Via Mangiagalli 34, Milano,
I 20133, Italy, Luca.Trombino@unimi.it, (2) Soil Branch, IPLA s.p.a, Corso
Casale 476, Torino, I 10132, Italy

A double transect in the low Sesia valley, from the river bed to the upper
oldest terraces (named "Baragge"), towards east and west, has been
recognized on the geological maps: the crono-toposequence could be
attributed to a fluvioglacial terraces chain, dated since the Middle
Pleistocene. In order to verify this attribution and increase knowledge to
a greater detail, a geopedological survey has been undertaken by means of
soil profiles excavation, on the different morphological surfaces,
additionally supported by frequent auger controls. Description, sampling
and analysis of soil horizons allowed to produce a broad data set for a
complete characterization of the geopedological aspects of the studied
area. Field and laboratory work has brought two levels of results: 1œ
Level: Land survey concluded by a soil map (1:50.000 scale) 2œ Level:
Analytic investigation for a better characterization of the chrono-topo-
sequence. The analytical protocol was constituted by: grain size and
routine pedological analyses, heavy minerals determination, X-ray
fluorescence and X-ray diffraction, micromorphology of soil thin sections,
in order to use the most significant (paleo)pedological indexes (i.e. soil
development index, percentage of original content of elements remaining,
parent material uniformity index.). The final results can be summarised as
follows: 1. The quantitative characterization of the chrono-topo-sequence;
2. An improved focus on pedogenesis factors in the Quaternary
paleoenvironment of Northern Italy; 3. A tentative methodological
contribution to define and classify paleosols; 4. An unusual data set as
support of a soil map, which can be utilized to derive, with high
precision, suitability maps, useful for land planning according to
agricultural and environmental targets; 5. A strict interaction between
quaternary geologist and pedologist with exchange of information and
methodological confrontation.

AGE AND ENVIRONMENT OF LOESS SEDIMENTATION IN NORTHERN ITALY DURING THE
EARLY UPPER PLEISTOCENE (STAGES 4 AND 3)
TROMBINO, Luca1, CREMASCHI, Mauro1, FERRARO, Francesca1, NEGRINO, Fabio2,
and TERHORST, Birgit3
(1) Earth Sciences Department, Univ of Milano, Via Mangiagalli 34, Milano,
I 20133, Italy, Luca.Trombino@unimi.it, (2) Department of Archaeology, Univ
of Pisa, Via S.Maria 53, Pisa, I 56126, Italy, (3) Institute of Geography,
Univ of Tuebingen, Hoelderlinstrasse 12, Tuebingen, D 72074, Germany

Recent research on loess deposits in Northern Italy and systematic TL and
radiocarbon dating of the loess deposits, put in light an innovative
scenario of glacial loess environment. Furthermore, loess are
systematically associated to Mousterian sites, testifying adaptation to
open environments in its paleoenvironmental and geoarchaeological
implication ad the loess sedimentation was contemporary on both Alpine and
Apennines fringes and it spanned from 60 to 26 ky. Phases of intense dust
accumulation were contemporary to the coldest and driest phases of the
Upper Pleistocene, and were interrupted by phases of absence of
sedimentation, during which soil forming processes occurred; three
interstadial isohumic soils were formed at this period. Early Upper
Pleistocene loess, is systematically connected to Mousterian sites, some
consisting of thick sequences insides caves; at the lower margin of loess
sedimentation area, most of them are related to hunting camps widespread
inside the loess covered area. A number of these sites are related to raw
material procurement, located in marginal areas very close to the glacier
front or at the upper limits of the loess sedimentation area, close to
periglacial regions.

SOIL GENESIS RELATED TO MEDIEVAL WARM PERIOD'S CLIMATIC FLUCTUATIONS IN
SOUTHERN PATAGONIA AND TIERRA DEL FUEGO (ARGENTINA). CHRONOLOGICAL AND
PALEOCLIMATIC CONSIDERATIONS
FAVIER-DUBOIS, Cristian M.
CONICET-INCUAPA, ArqueologÌa, Facultad de Ciencias Sociales (UNCPBA),
Avenida del Valle 5737, OlavarrÌa B7400JWI Argentina,
cfavier@coopenet.com.ar.

Geoarchaeological work carried out in five localities in Southern Patagonia
and Northern Tierra del Fuego has demonstrated the presence of a
pedogenesis interval represented by a mollisol, in the upper section of
widespread late Holocene aeolian and colluvial deposits. This soil is
buried at the archaeological sites under study but remains exposed in other
areas of the same landscape. The mollisol's origin and development may
indicate an important change in environmental conditions due to the
stabilization of regional aeolian and colluvial systems at that time.
Furthermore, there are changes in the distribution of the archaeological
record that are linked to this development. Radiocarbon dates on materials
found beneath this soil (maximum ages) and those by OCR (Oxidizable Carbon
Ratio) in the AC horizon (minimum ages) indicate the beginning of its
development around the year 1000 BP. Chronologically, there appears to be a
correspondence between the beginning of the mollisol and the presence of
climatic anomalies in southern eastern flank of the YedigÆller plateau, at
around 1800 m, moraines overly the doline fields of typical tropical karst
(cockpit type). At higher elevations, all pre-glacial karstic landforms
have been destroyed and many of the sinkhole type caves are blocked by
till. However, the accesible caves in the form of vertical shafts usually
terminate at till. Many of the open shafts above 2200 m contain snow, firn
and ice that contains gas inclusions and layers of till. A thickest (up to
120 m) record of snow, firn and ice was discovered in a vertical karstic
shaft located at ca. 3400 m. Preliminary results from our two years of
field work in the Aladaglar show that the Pleistocene glaciation was much
more widespread than previously thought. Future work will include
cosmogenic 36Cl dating of morainic boulders, 14C dating of glacio-lacutrine
material and U/Th dating of speleothems found within ice in the karstic
caves.

USING EXISTING SOIL DATABASES TO CONSIDER PALEOSOLS IN LAND PLANNING
COSTANTINI, Edoardo A.C.1, MALUCELLI, Francesco2, BRENNA, Stefano2
(1) Soil Genesis, Classification and Cartography, Ist. Sper. Studio e
Difesa Suolo, Piazza M. D'Azegio 30, Florence, 50121, Italy,
costantini@issds.it, (2) ERSAF-Lombardia Region Agency for Agriculture and
Forest, via Ponchielli, 2/4, Milano, 20124, Italy

Land Planning at the regional scale makes use of soil information in a
great deal of evaluations, most of them related to the economical
productive sectors, in particular agriculture and environment. Soil in this
ambit is considered as a resource for which the characteristics and
properties are measured, and its qualities and suitability for a variety of
purposes are assessed. However, there is a growing interest in applying
Land Planning to preserve the cultural heritage of the territory, and the
role that soil can play in such evaluation is often underestimated.
Paleosols are particularly worthwhile in this role of "containers of
information", and Land Planning aimed at preserving the cultural heritage
of the landscape should take into account the presence of Paleosols. This
study was conducted to set up a methodology which could be applied on
existing soil database to implement Land Planning for soil information
related to Paleosols. The methodology considered all the Po river Plain
area and moraine hills of the Lombardia region and utilized a soil database
built at the 1:50,000 scale. Other informative layers used were the
pedolandscape units, parks and urban area, all at 1:250,000 scale. The area
is constituted by glacial Late Pleistocene deposits and Holocene alluvial
sediments. The rating considered some selected soil characteristics and
gave them a different weight. The scored characteristics were: i) presence
of buried horizons, ii) presence of some diagnostic horizons such as
fragipan, plinthite, iii) Soil Taxonomy classification at the great groups
level, iv) redness rating of the B horizons. The evaluation started from
the selection of the pedolandscape units of geological interest and then
took into account soils and cartographic mapping units. The overlay with
the parks thematic map allowed to estimate the extension of the not already
protected paleosols. The presence in polygons with paleosols of urban areas
for more than 20% gave an appraisal of the risk of loss of the cultural
value of the landscape.

ADDING INFORMATION ABOUT SOILS AND PALEOSOLS TO GEOLOGICAL MAPPING. A GIS
APPLICATION IN CENTRAL ITALY
COSTANTINI, Edoardo A.C.
Soil Genesis, Classification and Cartography, Ist. Sper. Studio e Difesa
Suolo, Piazza M. D'Azegio 30, Florence, 50121, Italy, costantini@issds.it,
NAPOLI, Rosario, and D'EGIDIO, Giorgio

Soil survey and study of paleosols can add a great deal of information
useful to the comprehension of Quaternary geological and geomorphological
processes, but they are rarely reported in geological maps, perhaps due to
the difficulty in individuating and mapping pedostratigraphic units. This
study was conducted to qualify Quaternary formations in terms of
pedostratigraphic units and to test the possibilities offered by the use of
GIS and 3D tools in implementing existing geological maps with soil survey
and information about paleosols. The territory studied, measuring around 35
km2 and situated in Central Italy, is part of a broad ridge emerging from
the sea during the Miocene age and undergoing intense geomorphological
evolution during the Pliocene and Quaternary Periods. Many rock types and
sediments outcrop in the area. They are metamorphic rocks, mainly free of
carbonates, calcareous rocks, and slope and alluvial deposits derived from
the local bedrock.We used as geological reference the recent map published
by the Department of Earth Science of the University of Siena, at 1:25,000
scale, where the Quaternary sediments are described as alluvial or eluvial-
colluvial deposits. The GIS was built on ArcGIS8® and ArcScene® was used to
provide a tri-dimensional view of spatial distribution of pedostratigraphic
units as well as to obtain cross sections of the area. Three
pedotratigraphic units were proposed, according to the presence of
different diagnostic horizon assemblages and selected chemical and physical
characteristics of horizons and parts of them. Following former
paleopedological studies, they were attributed to Early, Middle and Late
Pleistocene, and Holocene. Three soil maps at 1:10,000 and 1:25,000 scales
were combined and harmonized, 27 benchmark profiles were analyzed, and each
soil map unit was classified in terms of occurrence and thickness of the
three pedostratigraphic units. The pedostratigraphy map obtained was then
combined with the geological map, resulting in a more detailed subdivision
of Quaternary surface deposits. The tri-dimensional view of the geology-
pedostratigraphy map, as well as the cross sections, permitted appraisal of
the geographical and chronological relationships between rocks and
overlaying soils. tephra markers include: Kawakawa, Rangitawa, Onepuhi,
Kupe, Kaukatea, Potaka, Ridge, Pakihikura, Birdgrove, Ototoka, Table Flat
and Vinegar Hill Tephras. The identification of these Pleistocene TVZ-
sourced tephras within the ODP-cores, and their correlation to Wanganui
Basin is a significant advance for two reasons. Firstly, it provides an
even higher-resolution history of the TVZ than can be currently achieved
from the near-source record and secondly, it yields a detailed and reliable
tephrochronologic framework essential for future paleoenvironmental
reconstructions. [55196]

SOIL MICROMORPHOLOGY EVIDENCE FOR QUATERNARY CLIMATE CONDITIONS OF THE
UPPER SAVA RIVER CHRONOSEQUENCE, SLOVENIA
VIDIC, Natasa J.
Biotechnical Faculty, Agronomy Department, Univ of Ljubljana, Jamnikarjeva
101, Ljubljana 1111 Slovenia, njvidic@ucdavis.edu

Soil chronosequences are usually studied to investigate temporal trends in
soil properties. These studies assume that time is the primary soil forming
factor affecting soil properties and consider the influence of climate and
other factors considerably less important. Observed on macroscopic level,
soil morphology reflects the cumulative alteration of parent material by
soil forming processes and allows the examination of temporal trends,
whereas at the microscopic level the effects of soil forming factors can,
ideally, be separated. Paleoclimate interpretations derived from the
observations of soils of the upper Sava River chronosequence (20 Ka - 1.8
Ma, dated by 10Be and soil paleomagnetic analyses) formed in predominantly
carbonate outwash deposits were based on the examination of the nature and
distribution of pedofeatures in soil thin sections. The nature of
ferriargillans (FAs) observed in soils younger than 1 Ma suggests that
climatic conditions during interglacials (soil forming episodes) of the
last 1 Ma were similar to average post-glacial conditions. In contrast,
bright red hematite stained early generations of ferriargillans in the
oldest soil (1-1.8 Ma, paleomagnetic analyses) suggest that climatic
conditions in the area were significantly different during its early stages
of development as the present climate does not allow hematite formation.
Considerably warmer and/or drier climatic conditions conducive to hematite
formation must have prevailed in the area during the interglacials that
predated 1 Ma. European pollen records suggest considerably warmer
conditions from 1.6 to 2.1 Ma. Therefore, the presence of these FAs
indicates that the oldest soil is older than 1.6 Ma and further constrain
its age interval. 5945]







LIKHVIN (HOLSTEINIAN) INTERGLACIAL SOIL COVER RECONSTRUCTION BY
PALEOPEDOLOGICAL DATA FOR THE EAST EUROPEAN PLAIN, RUSSIA
DLUSSKY, Konstantin G1., MOROZOVA, Tatiana D.2,
(1)Earth & Atmospheric Sciences, Univ of Alberta, 126, Earth Sciences
Building, Edmonton, AB T6G 2E3, Canada, kdlussky@ualberta.ca; (2)Laboratory
of Evolutionary Geography, Institute of Geography, Russian Academy of
Sciences, Staromonetny line, 29, Moscow, 109017, Russia

The aim of this study is to elucidate long-term climatic change over the
East European Plain during the Middle Pleistocene. For this purpose, we
investigated about 40 loess/paleosol sections. We reconstruct the genesis
and secondary transformations of the oldest Middle Pleistocene interglacial
paleosol (the Inzhavino paleosol) in the Oka, Don and Dnieper River basins
(48-56œ N, 32- 44œ E). The Inzhavino paleosol corresponds locally to the
Likhvin interglacial and regionally to the Holsteinian interglacial of
Western Europe. Micromorphology indicates that the Inzhavino paleosol is
polygenetic and implies that boreal to sub-boreal conditions prevailed
during the stage of most pronounced soil formation, corresponding to the
thermal optimum of the Likhvin Interglacial. There are clear indications of
distinct preoptimal and post-optimal stages of soil formation. The soil of
the optimal stage has a zonal structure. In the northern part of the
region, it is distinguished by a conspicuous textural differentiation
through the profile (Ah-Ae-Btf-Bg). South of 52œ N, the eluvial horizon is
usually not pronounced morphologically, instead in situ weathering signs
are more evident (Ah-(Aej)-Btgj). South of 51œ N in the Don River basin and
south of 50œ N in the Dnieper River basin, the Inzhavino paleosol has a
chernozem-like profile with a thick Ah horizon, carbonate accumulations and
numerous krotovinas. The boundaries of the soil zones are aligned from WSW
to ENE, probably because of the influence of the Atlantic Ocean. In some
sections, for the pre-optimal stage of soil formation, there is
micromorphological evidence of an earlier generation of lessivage and humus
illuviation. These features are more pronounced in the NE part of the
region where they are accompanied by iron illuviation. There, we identify
two Bt sub-horizons. South of 52œ N, especially in the middle Dnieper River
basin, we observe a Btj horizon at the bottom of the optimal stage
chernozem-like solum. Humus accumulation is the most pronounced process for
the post-optimal stage. It is also distinguished by two Ah sub-horizons and
a very low position of the Ae horizon. Finally, there are two generations
of small-polygon cryogenic deformations at the top of the Inzhavino
paleosol.








EVOLUTION OF SOILS AND LANDSCAPES OF WETLANDS IN THE UPPER VOLGA LOWLAND IN
THE HOLOCENE: MULTIDISCIPLINARY STUDY
GRACHEVA, Raisa G.1, VANDERBERGHE, Jozef2, SOROKIN, Aleksey N.3,
SULERDJITSKIY, Leopold D.4, and CHICHAGOVA, Olga A.1
(1) Russian Academy of Sciences, Institute of Geography, Staromonetny
per.29, Moscow, 109117, Russia, gracheva_mr@mtu-net.ru, (2) Vrije
Universiteit, De Boelelaan 1085, Amsterdam, 1081 HV, Netherlands, (3)
Russian Academy of Sciences, Institute of Archaeology, Moscow, Russia, (4)
Russian Academy of Sciences, Geol Institute, Moscow, Russia

An integrative study of fluviolacustrine and bog deposits of wetlands of
Upper Volga Lowland including series of buried soils and evidences of Early
Man activity was made to reconstruct the climate and palaeohydrological
change in the Central Russia during the last 11,000 14C years. Study sites
are located within Zabolotskoe peatland developed in place of the former
bottom of a periglacial palaeolake Tverskoye. It is shown that the regional
time-space dynamic of soils and landscapes was tightly related to initial
topography of dried palaeolake bottom. Soil formation began not later than
10330 14C BP on the forest-free plain with inherited topography of
palaeolake bed. The carbonated organic rich well-structured soils were
widely developed. According to the interpretation of palynological spectra
from key sections and the oxygen isotope composition of bone phosphate the
annual temperature was 5œ and 10œ lower than at present, respectively.
During the Preboreal up to the beginning of the Atlantic, birch and pine
forests developed successively leading to soil leaching. Acid humic-
illuvial soils were formed. Impact of Mesolithic settlements resulted in
soil disturbance. In the Atlantic forests are widespread, while Luvisols on
loams and Podzols on sands, and raw-humus soils in the depressions under
alder forests were formed. Frequent forest fires are assumed to have
occurred around 7500 BP. Around 6000 BP bogging in depressions began; on
the high sites (0.5 m above) Luvisols and Podzols development was
continued, and human used this plots actively. At the Atlantic/Subboreal
transition complex soil cover from peaty boggy soils, Luvisols and Podzols
was formed. Around 2600 BP total flooding interrupted soil development
through lowland area bordering the Klin-Dmitrov Heights and lower than 130
m a.s.l. Shallow flow-through cold lake was formed. Not later than 1900 14C
BP a wet plain with temporary water channels, free and cut-off meanders and
local bog areas were formed. Around 730 - 640 BP alder and birch forests
spread widely. Relief intensity decreased due to ongoing peat accumulation.
The present time is characterized by ground water-level rise and secondary
soil carbonatization and gypsum formation. Supported by the Netherlands
Organization for Scientific Research (NWO). Project 047.009.002.







NEW DATA FROM LOESSES AND PALEOSOLS OF THE US MIDWEST
RUTTER, Nataniel W.1, VELICHKO, Andrei A.2, DLUSSKY, Konstantin G.1,
MOROZOVA, Tatiana D.2, LITTLE, Edward C.3, NECHAEV, Vladimir P.2, and
EVANS, Ted4
(1) Earth & Atmospheric Sciences, Univ of Alberta, 126, Earth Sciences
Building, Edmonton, AB T6G 2E3, Canada, kdlussky@ualberta.ca, (2)
Laboratory of Evolutionary Geography, Institute of Geography, Russian
Academy of Sciences, Staromonetny line, 29, Moscow, 109017, Russia, (3)
Canada-Nunavut Geoscience Office, Nunavut, PO Box 2319, Iqaluit, X0A 0H0,
Canada, (4) Institute for Geophysical Research, Univ of Alberta, Edmonton,
AB T6G 2J1, Canada

Loess/paleosol series of the US Midwest provide long-term proxy records of
Quaternary sedimentation, climate and environments south of the glacial
limits of North America. Three key sections were investigated at Wittsburg
Quarry (Arkansas), Missouri Valley (Iowa) and Eustis Ash Pit (Nebraska) by
geochemical, paleomagnetic and micromorphological analyses. Below the
surface soil at each section, four loesses are present. They are separated
by three well-developed paleosols. The Crowley's Ridge loess is the oldest
loess unit at the sections under study. At Wittsburg, it lies on Pliocene
gravel, at Eustis it immediately overlies the Lava Creek B ash layer, and
at Missouri Valley it lies directly on the Pre-Illinoian till surface. A
well-developed paleosol modifies this loess at all three sections. This
paleosol has not previously been reported in western Iowa or eastern
Arkansas. At all three sites, it is immediately overlain by the Sangamon
paleosol solum which itself represents pedologically-altered Loveland
loess. This means that the Loveland loess is much thinner than previously
suggested. The Sangamon paleosol is well developed and readily correlated
between Wittsburg and Missouri Valley, but is probably partly eroded at
Eustis. It has luvisolic properties but with much more clayey pedogenic
texture than modern luvisols, and has no clear eluvial horizon. The
overlying Roxana loess at Wittsburg and its equivalents at Eustis and
Missouri Valley are mostly altered by soil formation. At Wittsburg and
Missouri Valley, this soil is called the Farmdale paleosol. On the basis of
its pedogenic features it correlates to the Gilman Canyon Formation
paleosol at Eustis. This soil has chernozemic properties at all three
sections, but at Wittsburg it is less developed. At all three sections,
this soil has ancient krotovinas, hence the gley features observed must be
interpreted as post-burial changes. In the upper part of all the sections,
the thickest Peoria loess is developed and shows the properties most
typical of loess. From the Peoria loess to the Loveland loess, the
correlations proposed are well corroborated by numerous published TL and
14C dates. Below the Loveland loess, only a few TL dates are available.
Mass-specific magnetic susceptibility and its frequency-dependence
correlate well with lithology and have maxima at the top of each paleosol.
deposition age of diamicts and fluvial deposits that relate spatially to
the lacustrine sequence. Ages between 200±43 ka b.p. to present were
determined. Absolute age has been estimated for the upper 34 m of the
lacustrine sequence. Its age spans from 12790±85 radiocarbon years b.p at
the depth of 34 m to 5885±60 radiocarbon years b.p. at the very top of the
sequence, yielding calculated sedimentation rate of 5 mm of compacted
sediment per year. A simple extrapolation of age vs. depth shows that
continuous sedimentation in the lake might have covered the period as long
as 40.000 years. Such a record with possible climatic implication is unique
in the area of the SE Alps and we believe that the interest exists in the
broader scientific community for further investigations of the record.We
are therefore looking for international cooperation that would enable us to
extract the sediment core in-whole and investigate its paleoclimatic
implications.

LATE QUATERNARY PALEOSOLS, LANDSCAPE EVOLUTION AND CLIMATE CHANGE IN THE
NORTHERN PAMPA, ARGENTINA
KEMP, Rob A.1, ZARATE, Marcelo2, TOMS, Philip3, KING, Matthew1, SANABRIA,
Jorge4, and ARGUELLO, Graciela4
(1) Geography, Royal Holloway, Univ of London, Egham Hill, Egham, TW20 0EX,
United Kingdom, r.kemp@rhul.ac.uk, (2) CONICET, Universidad Nacional de La
Pampa, Santa Rosa, Argentina, (3) GEMRU, Univ of Gloucestershire,
Cheltenham, GL50 4AZ, United Kingdom, (4) Facultad de Ciencias Exactas y
Naturales, Universidad Nacional de Cordoba, Cordoba, Argentina

The presence and characteristics of paleosols within loess sequences are
often interpreted in terms of regional and even global climatic changes. In
addition, they can be used to provide important insights into the
pedosedimentary evolution of a landscape. Despite containing the most
extensive loess cover in the Southern Hemisphere, there have been few
detailed studies of paleosols in the Argentinian Pampa. This paper reports
a pedosedimentary investigation of two Late Quaternary loess-paleosol
sections from the northern part of this region. Field and
micromorphological data indicate that the landscape at both sites has
experienced a cyclical development with relatively stable land surfaces
associated with significant soil formation (e.g. bioturbation, weathering,
leaching and clay translocation processes) being interspersed with phases
of instability, erosion, loess accumulation and accretionary pedogenesis.
The 7 m section at Baradero contains two paleosol units, the older one is a
pedocomplex whose upper part is correlated on the basis of optically-
stimulated luminescence dates to Oxygen Isotope Stage (OIS) 5a of the
marine record. The surface soil developed in Late Pleistocene loess is
significantly less developed than both paleosols, thus opening up the
intriguing possibility that the climate during the Holocene may have been
drier and/or milder than earlier warm stages and sub-stages. The only
paleosol recorded in the 9 m section at the Lozada site appears to date
from OIS 5a and is again more developed than the surface soil. In this
case, however, significant amounts of loess have accumulated throughout the
Holocene, perhaps supporting the notion that the comparative developments
reflect differences in length of 'soil-forming intervals' rather than
climate. This study not only emphasises the potential value of a
pedosedimentary approach to the interpretation of loess-paleosol sections,
but also highlights some of the difficulties of inferring regional climatic
changes from pedosedimentary reconstructions.



GEOGRAPHIC DIFFERENTIATION OF THE LAST INTERGLACIAL PALEOSOL S1 IN THE
CHINESE LOESS PLATEAU
FENG, Zhaodong1 POPE, Gregory2, OLSON, Carolyn G.3 WANG, Haibin4
(1) National Lab. of Western China's Environmental Systems, Lanzhou Univ,
Lanzhou, 73000, China, fengz@mail.montclair.edu, (2) Department of Earth
and Environment Studies, Montclair State Univ, Upper Montclair, NJ
07043,(3) National Soil Survey Center, USDA-NRCS, 100 Centennial Mall N,
Lincoln, NE 68508, (4)National Lab. of Western China's Environmental
Systems, Lanzhou Univ, Lanzhou, 730000, China

The net eolian deposition attenuated while the pedogenesis intensified
southeastward during the last interglacial in the Chinese Loess Plateau.
Consequently, the last interglacial paleosol S1 gradually differentiated
from the southeast to the northwest as follows. In the southeastern part,
multiple soil-forming events occurred in a single completely welded soil
profile. Towards the northwest, climate becomes drier and the loess becomes
thicker, and the multiple soils become partially welded (i.e., subsequent
soils "annexed" the upper portions of previous soils). Moving further
towards the northwest, each one of the multiple soils becomes completely
separated. In the northwestern part, not only are the multiple soils
completely separated, but also the loess units between the soils are well
preserved. In all cases investigated, the coarse fraction content well
defines the upper and lower boundaries of the S1 parent material and can be
used to estimate the time-transgressive nature of the S1 paleosol relative
to its parent material. Soil welding, bioturbation and material
translocation (e.g., clay and carbonate) within the S1 profiles make it
impossible to preserve the high-resolution information of the last
interglacial (128-73 ka) climate changes in most parts of the Chinese Loess
Plateau. First, clay translocation within the S1 profiles has moved some of
the magnetic minerals downward so that the susceptibility only reflects the
posttranslocation distribution of the susceptibility-producing minerals.
Second, the best-developed paleosol S1S3 (i.e., MIS 5e) at most of the
sections is not expressed by the susceptibility because the S1S3 developed
into underlying coarser and lower-susceptibility loess (i.e. L2). Third,
the carbonate concentration dilutes the susceptibility signature. At most
of sections investigated, the post-depositional in situ weathering and the
post-weathering clay translocation within the S1 profile occurred and post-
depositional carbonate leaching and accumulation are observable throughout
the S1 profiles. Equally important is the downward development of the S1
into the underlying coarser loess (L2). These mean that both the
susceptibility (summer monsoon proxy) and the particle size (winter monsoon
proxy) are problematic as quantitative climatic proxies.








SOIL COMPLEXES ON TERRACES IN THE SOUTHWEST OF THE NORTH ISLAND OF NEW
ZEALAND
PALMER, Alan S, SENARATH, Asoka, TILLMAN Russ W.
Soil and Earth Sciences, Massey Univ, PB 11-222, Palmerston North, New
Zealand, a.s.palmer@massey.ac.nz

Soil complexes are a common feature of the soil pattern on loess and loamy
alluvium covered terraces in the southwest of the North Island of New
Zealand. The complexes occur where rainfall is between 900 and 1250mm per
annum, and where mean annual temperature is 11-13 degrees. Soil moisture
regimes are ustic and udic. Several soil complexes occur on interglacial
marine terraces with multiple unit loess cover, separated by paleosols, and
several metres thick, overlying beach, coastal or dune sands. Soils range
from well drained Hapludands to poorly drained Fragi- and Endoaqualfs.
Similar complexes occur on river aggradation terraces older than the last
glacial with one to several units of loess cover. Other soil complexes
occur on last glacial river aggradation terraces where loamy alluvium 0.5 -
several metres thick overlies gravels. Soils range from well drained
Dystrudepts to poorly drained Endoaquepts. The complexes occur on flat to
gently undulating land without topographic control, and all members in the
complex from well to poorly drained can be present within a radius of 50m.
There appears to be no relationship between loess or alluvium thickness and
soil class, nor a relationship with the topography of the underlying loess
or gravel. However, the water content of the underlying unit may be
important. The well drained members of the soil complexes commonly contain
allophane, while poorly drained members are often dominated by kandite
clays. It appears that a template is established early in the weathering of
the parent material that promotes certain pathways of clay mineral
formation, and in turn diverse soil properties. The presence of the soil
complexes has important implications for intensive land uses, and pose a
challenge for precision agriculture.

A NEW INSIGHT INTO PEDOGENIC PROCESSES IN AN EXTREMELY ARID ENVIRONMENT AND
ITS PALEOCLIMATIC IMPLICATIONS - THE NEGEV DESERT, ISRAEL
AMIT, Rivka1, LEKACH, Judith2, AYALON, Avner3, PORAT, Naomi3, and GRODEK,
Tamir2
(1) Geological Survey of Israel, 30 Malkhe Israel St, Jerusalem, 95501,
Israel, Rivka@mail.gsi.gov.il, (2) Geography, Hebrew Univ of Jerusalem,
Hebrew University of Jerusalem, Jerusalem, 91905, Israel, (3) Geological
Survey of Israel, 30 Malkhei Israel St, Jerusalem, 95501, Israel

It is well known that wet phases occurred in the Negev desert during the
Pleistocene and the Holocene. The question is whether these phases can be
detected in the soils and paleosols. Alluvial fan chronosequences in the
extremely arid areas of the Negev desert (< 80 mm rainfall) are
characterized by salic and gypsic Reg soils. These chronosequences are of
Pleistocene and Holocene age and range between 4 ka and 100 ka. Although
the soils that developed on stable surfaces are cumulative and polygenetic,
none of them show calcic horizons. The only environment in this extremely
arid area in which Quaternary calcic soils were detected is streambeds of
ephemeral flash flood channels. In these channels calcic soils were
developed under the active alluvial fill. Stratigraphic surveys conducted
in the alluvial fill of several such channels in the southern Arava Valley,
Dead Sea Rift, indicate the existence of an identical and highly
distinctive fluvio pedogenic unit (FPU) 50-100 cm beneath the surface. The
FPU has some initial attributes of a soil such as horizonation, calcium
carbonate deposition, iron oxides release and accumulation of fine-grained
material. The FPU forms at the lower limit of the contemporary scour and
fill processes under wet conditions but not under intensive leaching. It is
tied to the cumulative influence of persistent differences in water
availability to various parts of the channel before and during flood
events, which form a moisture regime equivalent to about 350 mm annual
rainfall. This moisture regime is conducive to the formation of a calcic
soil. The existence of the FPU in active channels and in terraces in this
extremely arid area shows that when there is enough moisture for calcic
soil to develop, such a soil will form. The lack of calcic soils and the
widespread presence of Holocene and Pleistocene salic-gypsic soils
emphasize that hyper arid conditions prevailed during the last 100 ka in
most of the Negev desert. This conclusion is also supported by the isotopic
composition of carbon and oxygen of the calcic nodules in the paleo and
recent FPU's (. 13C ranges from -2? to +3.5? and . 18O from -8? to +6?).
There was no indication for humid climatic conditions in the FPU's and the
Reg soils.

RECORD OF LATE QUATERNARY CLIMATE CHANGE IN CALCIC SOILS: INTERPRETATION OF
SOIL GEOMORPHOLOGY AND HYDROLOGIC MODELING
MCDONALD, Eric
Earth and Ecosystem Sciences, Desert Rsch Institute, 2215 Raggio Parkway,
Reno, NV 89512, emcdonal@dri.edu

Numerical modeling of soil moisture combined with morphologic and
hydrologic analysis of desert soils provides information about late
Quaternary climate change. Simulations of soil-water flux under varied
conditions are used to determine the impact of episodic periods of wetter
climate during the Holocene and latest Pleistocene on calcic soils and
ecosystem processes in the in the Mojave and Sonoran Deserts of the
southwest U.S. Analysis of atmospheric circulation patterns indicate that
historic wet years provide an analog for wetter climates that occurred
during the latest Pleistocene and episodically during Holocene periods of
pluvial activity. Daily weather data associated with a wet (~33 cm/yr) and
dry (~15 cm/yr) climate was used to simulate the affects of climate change
on soil-water balance and the bimodal distribution of carbonate in soils on
Pleistocene surfaces in the Mojave Desert. Results indicate that soil-water
balance for dry and wet years strongly corresponds with the upper and lower
zones of carbonate accumulation respectively. Soil water only reached the
lower zone during wet years due to an increase in winter and spring frontal
storms. This relation indicates that the upper carbonate zone is due to a
decrease in rainfall and not an increase in Holocene temperature or the
development of clay-rich soils. Calculation of carbonate solubility and
accumulation rates suggests that much of the carbonate in the upper zone
accumulated during the late Holocene rather than throughout the entire
Holocene. Simulations of soil water balance provide clues about climate
change and the formation of plants scars, features common to areas of
extensive desert pavement in the hyper-arid areas of the Sonoran Desert.
Plants scars are circular areas 2-5 m across that are devoid of vegetation
and often lack pavement. Soil morphology underlying the scars preserves
evidence of a biologic origin of the scars. Modeling soil-water flux
suggests that a decrease in large storms that produce surface runoff from
pavement covered soils marginal to the scars has resulted in a substantial
decrease in plant available soil water, enhancing plant mortality.
Formation of plant scars from an interaction of biologic and pedologic
processes implies changing environmental conditions and may record long-
term trends in regional climate.

MODELLING THE DISTRIBUTION OF SOILS AND SOIL PROPERTIES ACROSS THE
AUSTRALIAN CONTINENT
BUI, Elisabeth N.1, HENDERSON, Brent L.2, VIERGEVER, Karin3
(1)CSIRO Land and Water, GPO Box 1666, Canberra, ACT 2601, Australia,
elisabeth.bui@csiro.au, (2)CSIRO Mathematical and Information Sciences, GPO
Box 664, Canberra, ACT 2601, Australia, (3) Centre for Geo-Information,
Wageningen Univ and Rsch Centre, PO Box 47, Wageningen, 6700 AH,
Netherlands

We have modelled the distribution of soils and soil properties across the
agricultural zone on the Australian continent using data mining and
knowledge discovery from databases (DM&KDD) tools. Piecewise linear
decision trees were built using 19 climate variables, DEM and derived
terrain attributes, 4 Landsat MSS bands, and lithology maps as predictors
of soil pH, organic C... The climatic variables were derived from daily
climate records for the 20-year period from 1980 to 1999. From these daily
records 20-year monthly average surfaces were interpolated for 19 climatic
variables: annual mean temperature, mean diurnal range, isothermality,
temperature seasonality, maximum temperature of warmest month, minimum
temperature of coolest month, temperature annual range, annual
precipitation, precipitation of the wettest and driest months,
precipitation seasonality, annual mean radiation, highest and lowest
monthly radiation, radiation seasonality, annual mean moisture index,
highest and lowest month moisture index, and moisture index seasonality.
Predictor variables can feature as splitting criteria in sub-setting the
dataset and in the linear regressions at each leaf of the decision trees.
The details of the method have been submitted for publication (Henderson et
al. 2001, http://www.clw.csiro.au/publications/technical2001) so here I
will focus on whether there is any knowledge discovery from data mining of
the soillandscape databases in Australia. The climatic variables feature
prominently in all models but different climatic variables appear in
different models. For the topsoil pH model, the precipitation in the driest
month and the annual mean soil moisture feature most prominently in the
condition (sub-setting) rules and in the regression rules. For the subsoil
pH model, the annual mean soil moisture and the lowest monthly solar
radiation are most important. For the topsoil organic C model, the annual
mean soil moisture is most important. The most used terrain attributes are
generally elevation, relative elevation, and relief. The four bands from
the Landsat MSS are also important predictors in all models.What and where
variables are being used in each of the predictions will be presented and
discussed.

MAGNETOSTATIGRAPHY OF AN EARLY-MIDDLE MIOCENE LOESS-SOIL SEQUENCE IN THE
WESTERN LOESS PLATEAU OF CHINA
HAO, Qingzhen1, GUO, Zhengtang2, QIAO, Yansong1, PENG, Shuzhen1, WEI,
Jianjing1, and ZHANG, Zhongshi1
(1) Institute of Geology and Geophysics, Chinese Academy of Sciences, P.O.
Box 9825, Beijing, 100029, China, haoqz@163.net, (2) Institute of Earth
Environ, Chinese Academy of Sciences, Xian, 710075, China, ztguo@95777.com


Earlier studies on two parallel sections (QA-I and QA-II) in the Qinan
region from the western Loess Plateau demonstrated that loess deposition in
northern China started by 22 Ma ago, indicating the onset of Asian
desertification and winter monsoon circulation by the early Miocene time. A
third section, 218.2 m thick, about 30 km east of the previously studied
sections, is geomagnetically dated in this study. The upper portion (0-
166.5 m) of this section consists of alternat- ing typical loess and soil
units while the lower part (166.5 m-218.2 m) is water-reworked, but the
material was derived from loess deposits. Thermal demagnetization was
performed on 853 samples at an average interval of 25 cm. Samples were
demagnetized in a MMTD-600 Thermal Demagnetiser and measured using a 2G
three-axis cryogenic magnetometer, both installed in field-free space. Most
of the samples yield a stable characteristic remanent magnetization (ChRM)
above 350 degree and 91% of the samples gave reliable characteristic
remanence directions. The obtained magnetic polarity zonation is well
correlative with the portion from the Chron C6Ar to Chron C5r.3r of the
GPTS without any significant hiatus. Extrapolation based on sedimentation
rate indicates a time span of the sequence from 21.4 Ma to 11.6 Ma BP. The
boundary between the typical loess-soil sequence and water-reworked lower
portion is dated for 19.6 Ma. Lithostratigraphy and magnetic susceptibility
of the sequence are consistent with the geomagnetic results. They show high
similarity and correlativity with those of the QA-I and QA-II sections.
These results firstly confirm our earlier studies that loess deposition
started in northern China by the early Miocene, and secondly demonstrates
that the stratigraphy of the Miocene loess-soil sequences is spatially
correlative, having therefore great potential for the study of
regional/global climate changes during the Miocene time. The Miocene loess-
soil sequences, combined with the well-known Quaternary loess-soil sequence
and the Late Miocene-Pliocene Hipparion Red-Earth formation, provides a
unique continuous eolian record of paleoclimates since the early Neogene.

PALEOCLIMATE IMPLICATIONS OF MAGNETIC PROPERTIES AND MINERALOGY OF THE
CHINESE LOESS/PALEOSOL COUPLETS OF THE LAST 1.2 MA
DENG, Chenglong, ZHU, Rixiang
Institute of Geology and Geophysics, Chinese Academy of Sciences, POB#9825,
Beijing, 100029, China, cldeng@mail.igcas.ac.cn

A multiparameter investigation of 15 loess-paleosol couplets (S0/L1 to
S14/L15) from the Jiaodao section sequence in the central loess plateau of
China using mineral magnetic approaches was conducted. The magnetic
parameters display systematic variations that seem to be closely related to
paleoclimate variations and intensity of pedogenesis. High-temperature and
high-field magnetic properties exhibit systematic variations that can be
directly related to magnetic mineral transformations by pedogenic
processes. High-temperature susceptibility curves of paleosols show a
generally decreasing trend in reversibility from the base of the Lishi
Formation to the Holocene black loam, indicating a decrease in weathering
intensity. This may reflect a long-term increase in aridity and/or a
general long-term cooling trend of the interior of the Asian continent from
1.2 Ma ago to the present. Some samples display wasp-waisted hysteresis
loops. These are most pronounced in moderately enhanced paleosols, less
pronounced in the practically unaltered loess, and subdued in the well-
developed paleosols, but wasp-waistedness reappears in the most developed
paleosols. These magnetic variations in Chinese loess and paleosols are
jointly controlled by the changes in composition, concentration and grain-
size, but each variable has different effects at different stages of
pedogenesis.

PERIODICITIES IN LOESS-PALEOSOL SEQUENCE OF CHINA
LU, Huayu1, ZHANG, Fuqing, LIU2, DUCE, Robert3
(1)State Key Laboratory of Loess and Quaternary Geology, Chinese Academy of
Sciences, No.10, Fenghui Nanlu, Xi'an, 710075, China, luhuayu@llqg.ac.cn,
(2)Xiaodong, Xi'an 710054, (3) College Station, TX, USA

Periodicity in Chinese loess-paleosol sequence has long-time been
investigated. However, there are many drawbacks in the previous works so
that the conclusions are still controversial and the interpretation is
equivocal. In this study, two typical loess-paleosol sequences (148 m and
191 m in thickness, respectively) in the Loess Plateau are sampled and
total 2872 samples are measured in order to reconstruct the palaeoclimatic
changes during the past three million years. On the basis of the new and
sensitive proxy indicator of paleoclimate and the newly developed
independent (orbitally-untuned) time scale, time series of the dust storm
variations, which is highly related to the paleoenvironmental system
changes, is obtained. By wavelet transfer and power spectrum analyses, the
results show that there are approximately 400, 200, 100, 66, 57, 41, 31, 27
and 22 kyr cycles in the loess record. The orbital cycles are weak and are
not completely presented in the new time series; there are also non-orbital
cycles. Because the eccentricity frequencies of the solar irradiance of the
approximately 400-kyr and 100-kyr are preserved in these sequences, the
missing of 41-kyr-obliquity and 22-kyr-precession cycles in part of the
time series may be explained by lower time-resolution of the loess-paleosol
deposit. The presentation of the nonorbital cycles may be explained by the
unstable depositional process of the dust and pedogenic process in the
paleosol units, which misrepresents or obliterates imprint of the solar
irradiance frequency. This conclusion may imply that it should be cautious
when investigate the specific paleoenvironmental changes recorded in the
loess, especially in the paleosol units.

CARBON ISOTOPE RECORDS FROM THE LOESS-PALEOSOL SEQUENCES FOR C3/C4 PLANT
VARIATIONS IN THE LOESS PLATEAU DURING THE LAST 150 KA BP: IMPLICATION OF
VEGETATION RESPONSE TO CLIMATIC CHANGES
GU, Zhaoyan1, LIU, Qiang1, XU, Bing1, HAN, Jiamao1, DING, Zhongli1, LIU,
Tungsheng1, and LAL, Devendra2
(1) Institute of Geology and Geophysics, Chinese Academy of Sciences, P O
Box 9825, Beijing, 100029, China, zgu@95777.com, (2) Geological Research
Division, A-0224, Scripps Institution of Oceanography, La Jolla, CA 92037

It is important to understand which is the major factor to drive ecological
changes on a regional scale since our atmospheric CO2 level is increasing
because human activities. In this presentation, the analyses of carbon
isotope of organic matter, grain size, carbonate, and magnetic
susceptibility have been carried out on the samples from the loess-paleosol
sequences at different sites in Chinese Loess Plateau for the histories of
C3/C4 plant abundance and climate since the last interglacial. The
following conclusions emerge from the analytic data. First, the fact that
the flora are characterized by a mixture of C3/C4 grasses during relative
warm periods except for the last interglacial (equivalent to Eemian in
Europe), and by a C3 grass domain during relative cold periods of the last
150 ka BP indicates that temperature is the major factor to induce changes
in C3/C4 abundance. This conclusion is also supported by an increasing
trend of C4 plant abundance for a given period from the cold northwest to
the warmest southeast of the Loess Plateau. Second, the C4 plant abundance
during warm periods increase with seasonal intensity of precipi- tation
and/or dryness, implying that the East Asian monsoons play an important
role in the plant photosynthetic type when the temperature is high enough
to grow C4 plants. Finally, a great contrast in the C3/C4 plant abundance
is presented between Holocene and the Eemian, when atmospheric CO2 level
was high for both of the periods. The Holocene flora is a mixture of C3/C4
grasses in the plateau. However, the Eemian flora become into a C3 plant
domain only in the southeastern plateau. Since the Eamian climate is the
warmest in the last 150 ka BP, it can be deduced that forest had fully
covered on the southeastern plateau due to reducing of the seasonality of
precipitation during that period.




PARTICLE SIZE DISTRIBUTIONS OF THE LAST INTERGLACIAL PALEOSOL S1 PROFILES
IN THE CHINESE LOESS PLATEAU: THEIR PEDOGENIC AND CLIMATIC IMPLICATIONS
WANG, Haibin1, FENG, Zhaodong2
(1) National Lab. of Western China's Environmental Systems, Lanzhou Univ,
Lanzhou, 730000, China, hbwang@21cn.com, (2) Department of Earth and
Environment Studies, Montclair State Univ, Upper Montclair, NJ 07043

The last interglacial paleosol S1 gradually differentiated from the
northwest to the southeast. At the Lanzhou and Dingxi sections in the
northwestern part of the Loess Plateau, the three paleosols (S1S1, S1S2,
S1S3) corresponding to marine isotope sub-stages 5a, 5c and 5e and the two
intervening loess units (S1L1, S1L2) corresponding to marine isotope sub-
stages 5b and 5d are completely preserved and the post-depositional in situ
weathering and the post-weathering translocation of clay and carbonate did
occur in the paleosols but only to limited extents. At the Tianshui section
in the southern part of the western Loess Plateau, the three paleosols were
partially welded, and the post-depositional in situ weathering and the post-
weathering translocation within the S1 profile occurred more pronouncedly
and the S1 intruded into the underlying older and coarser loess L2 more
deeply than in the northwestern part. The three soil-forming events
occurred repeatedly just in one single soil profile at the Lantian section
in the southeastern part of the Loess Plateau and a major portion of the S1
paleosol developed in the underlying older and coarser loess L2.
Undoubtedly, the post-depositional in situ weathering and the post-
weathering translocation within the S1 profile at the Lantian section were
the predominant processes probably during the entire period of the last
interglacial. The Qingyang section is an expanded version of the Lantian
section. The laboratory data at the Huanxian section in the northern part
of the eastern Loess Plateau are quite similar to those at the Qinan
section in the central part of the western Loess Plateau. At all sections
investigated with an exception of the Lantian section where the particle-
size difference between the L1 and S1 was blurred by a strong weathering of
the L1, not only are the paleosols but also the loess units S1L1 and S1L2
within the S1 remarkably distinguishable from the overlying L1 and
underlying L2 by particle size distribution, implying that the S1 parent
material was considerably finer in the source areas during interglacial
periods than during glacial periods. To conclude, because a number of
factors might have involved in shaping the particle size distribution curve
in the S1 profiles, it is thus unrealistic to reconstruct high-resolution
climatic records from the S1 paleosols.









PALAEOPEDOSEDIMENTARY AND ANTHROPOGENIC CHARACTERISTICS IN HOLOCENE LOESS
PROFILES OF CHINA
HE, Xiubin1, TANG, Keli2
(1) Soil Science, Chengdu Institute of Mountain Hazards and Environ, CAS,
No. 9, Block 4, South Renmin Road, Chengdu, 610041, China,
hexiubin@yahoo.com, (2) Soil Science, Institute of Soil and Water
Conservation, CAS, 26 Xinong Road, Yangling, 712100, China

Holocene loess-palaeosol profile is of special importance in loess-based
palaeo-climatic studies as it usually serves as the basis for interpreting
the eco-environmental conditions under which the older loess-palaeosol
sequences were developed. In China, a long agricultural history on the
Loess Plateau has caused extensive destruction of natural vegetation cover
and led a profound modification on the Holocene loess profiles.
Micromorphology, heavy minerals, pollen and soil properties are examined in
three typical Holocene loess profiles at three locations along a southnorth
transect across the Loess Plateau. Results show that the profile consists
of a palaeosol layer developed in the middle Holocene, which is underlain
by the Malan loess and covered human disturbed fresh loess. The palaeosols
were well preserved, consisting of an upper humusrich (AB) horizon and a
clay-rich (Bt) horizon. The humus-rich horizons are intensely weathered,
contain precipitated calcitic material derived from the overlying modern
loess, and have both high pollen content and diversity. Clay coatings are
common in the clay-rich horizons. The pedogenetic types of the palaeosols
varied from Ustalfs to Argiustolls and Haplustepts in the USA system along
the S-N transect with paleo-bioclimatic pattern of the middle Holocene. The
cover layers (Ap horizons) are newly-deposited loess of the later Holocene,
10%-25% of which in the south area was caused by human activities such as
application of plaggen manure and irrigation with sediment¨Crich water.

LATE QUATERNARY LOESS-PALAEOSOL SUCCESSIONS AND ATMOSPHERIC CIRCULATION,
CENTRAL SIBERIA
CATTO, Norm1, RUTTER, Nat2 EVANS, Ted3, CHLACHULA, Jiri4 NYVLT, Daniel5
(1) Geography, Memorial Univ, St. John's, NF A1B 3X9, Canada,
ncatto@mun.ca, (2) Earth and Atmospheric Sciences, Univ of Alberta,
Edmonton, AB T6G 2E3, Canada, (3)Institute for Geophysical Research, Univ
of Alberta, Edmonton, AB T6G 2J1, Canada, (4) Laboratory for Palaeoecology,
Technical Univ Brno, Zlin, 76272, Czech Republic, , (5) Department of
Quaternary Geology, Czech Geol Survey, Klarov 3, Prague, 11821, Czech
Republic

Aeolian sediments and palaeosols represent the principal forms of
sedimentation and hold the record of climate events in unglaciated central
Siberia. Loess-palaeosol records in the Gorno- Altaisk, Biysk, and
Krasnoyarsk regions indicate establishment of periglacial steppe-tundra
during OIS 4 and OIS 2, replaced by parkland steppe and boreal forest
during warmer intervals within OIS 3. The last interglacial maximum
occurred ca. 125,000 BP, earlier than OIS 5e in Europe and North America. A
gradual transition from parkland-steppe (OIS 5a) to moist tundra conditions
(OIS 4) occurred ca. 75,000 BP. General cooling, punctuated by isolated
short warm intervals, marked the period from ca. 75,000 to ca. 25,000 BP.
OIS 2, ca. 25,000-18,000 BP, was marked by a sharp change to a dry tundra
climate, followed by rapid warming ca. 15,000-8,000 BP. Mid- and latest
Holocene conditions were warmer than those recorded during the OIS 5e
maximum. Textural, magnetic susceptibility, and mineralogical analyses
indicate that the OIS 4 and OIS 2 loess units were derived from different
source areas. The mineralogy of the clay-rich OIS 4 loess indicates
derivation from the Altai Mountains to the south, and is associated soft
sediment deformation indicates niveo-aeolian deposition. The OIS 2 loess is
coarser, distally derived from western sources, and was deposited under
colder, drier conditions. The changes in loess mineralogy and texture thus
record a shift from southerly winds during OIS 4 to western
zonal/hemispheric circulation during OIS 2. OIS 2 was marked by an abrupt
change in climate, in contrast to the gradual transition evident from OIS
5a through OIS 3. Each successive interstadial was marked by cooler and
drier conditions than its predecessor. The similarity between climate
successions in Siberia with those recorded in the central Russian Plain
suggests that continental-scale changes in airmass circulation were ongoing
during the Late Quaternary in northern Eurasia.

DROUGHT PERIODICITY OVER THE PAST 2000 YEARS IN THE AMERICAN SOUTHWEST
SCUDERI
Louis A.
Earth and Planetary Sciences, Univ of New Mexico, Northrop Hall,
Albuquerque, NM 87131, tree@unm.edu

Tree ring records from 117 precipitation sensitive sites in the Four
Corners area of northeastern Arizona, northwestern New Mexico, and southern
Utah and Colorado were used to reconstruct annual precipitation variability
over the region for the last 2000 years. Response functions for individual
chronologies suggest that total precipitation for a 12-month period from
the prior September to August of the growing season can be usefully
reconstructed at these individual sites. Because of general similarities in
the precipitation response for all 117 chronologies they were combined to
produce a master regional chronology with greatly enhanced chronology
depth. The reconstructed series shows that precipitation has varied in a
regular manner with alternating wet and dry periods over the last 2000
years. The reconstruction for individual years ranges from a minimum of
19.2cm (AD 980) to a maximum of 56.8cm (AD 636). The wettest 20-year
interval occurs from AD 1905-1924 (mean 43.4 cm/yr) while the driest occurs
from AD 1573-1592 (mean 30.7 cm/yr). This reconstruction confirms that some
earlier droughts were multidecadal with several (centered on AD 615, 710,
1090, 1280, 1450 and 1580) exceeding drought magnitudes experienced in the
20th century. Long-term trends in the reconstruction are indicative of an
~70-year periodicity in precipitation totals. Documented wet and dry
periods over the instrumental record and drought periods prior to 1895
reconstructed from other proxy data sources appear to be closely linked to
this variability. Superimposed on this longer periodicity is an interval
from 800 to 1200 AD during which shorter period precipitation variability
dominates the record. A change to higher magnitude events and rapid
transitions from wet to dry conditions may be indicative of a climatic
shifts in the 13th and 20th centuries.

QUATERNARY HISTORY OF MISSOULA FLOODS IN OREGON BASED ON SOILS
BURNS, Scott F., JAMES, David, CORDERO, David, and LAWES, John
Geology Department, Portland State Univ, P.O. Box 751, Portland, OR 97207,
burnss@pdx.edu

The Missoula Floods have a record found in the soils of the Willamette
Valley of Oregon. Soils are mainly Inceptisols and some are Alfisols in the
flood deposits of the Willamette Silts. A chronosequence has been
established with Bw horizons developing in 5000 years and Bt horizons in
12,000 years. Five older paleosols have been found near The Dalles, Oregon
that have stage 4 carbonate horizons in the lower two. A tephra identified
as 600,000 years old is found in the third paleosol. This sequence of
paleosols ranges from the late to the early Pleistocene. Loesses of the
Portland Hills also show paleosols that range back to the middle of the
Pleistocene. Rhythmites found in Portland and near Dayton, Oregon also show
changes in the chemistry of the finegrained phases of the deposits. From
the earlier floods to the latest floods there is an increase of iron and
scandium with corresponding decreases in chromium. These values can be used
to identify where rhythmites might be in the overall sequence of the 12,700
- 15,300 BP floods of the Missoula Floods.

SEDIMENT MAGNETIC SIGNATURE OF CLIMATE IN MODERN LOESSIC SOILS FROM THE
GREAT PLAINS
GEISS, Christoph E.1, ZANNER, C. William2, Keim Hall3, James H.4,
(1) Physics, Trinity College, McCook Hall 105, 300 Summit St, Hartford, CT
06106, christoph.geiss@trincoll.edu, (2) School of Natural Resource
Sciences, Univ of Nebraska, 133 (3) Lincoln, NE 68583-0915, BISBEE, (4)
Trinity College, 300 Summit St, Hartford, CT 06106

We sampled 17 modern soils along a SW-NE trending transect through Nebraska
and western Iowa for pedologic and sediment magnetic analyses. Selecting
soils developed in loess on stable upland summits allowed us to isolate
modern climate as the main influence on soil properties. These sites were
complemented by four soils developed in sandy material and seven soils
developed in strongly dissected terrain in order to test the sensitivity of
our approach to non-climatic influences. All loessic sites contain
magnetically enhanced A-horizons, characterized by higher values of
magnetic susceptibility, anhysteretic remanent magnetization (ARM) and
isothermal remanent magnetization (IRM) as compared to the unaltered parent
material. For sites developed in stable upland positions the correlation
between magnetic enhancement and modern precipitation is best when using
grain-size dependent parameters such as ARM (r2=0.7) or ARM/IRM (r2=0.8) to
describe changes in magnetic properties. Enhancement in magnetic
susceptibility, which has been used successfully in Chinese loess-paleosol
sequences to reconstruct changes in paleoprecipitation, follows the modern
precipitation gradient to a lesser degree (r2=0.3). The better performance
of ARM or ARM/IRM as a predictor of modern precipitation is due to the high
sensitivity of these parameters to small (d=0.01 - 0.1 Ëm), single domain
(SD) grains of pedogenic origin. Soils from erosion prone locations show a
lower degree of magnetic enhancement due to the continuous loss of
magnetically enhanced A-horizon material, while sandy soils show generally
very little enhancement regardless of landscape position.

PALEOENVIRONMENTAL INFERENCES FROM .13C OF SOIL ORGANIC CARBON IN 14C-DATED
PROFILES IN THE U.S. GREAT PLAINS
FOLLETT, Ronald F.1, LEAVITT, Steven W.2, KIMBALL, John M.3, PRUESSNER,
Elizabeth G.1
(1) Soil Plant Nutrient Research, U.S. Dept. of Agriculture - ARS, 301 S.
Howes, Room 407, Ft. Collins, CO 80522, rfollett@lamar.colostate.edu, (2)
Lab. of Tree- Ring Research, Univ of Arizona, 105 W. Stadium, Bldg. #58,
Tucson, AZ 85721, sleavitt@ltrr.arizona.edu, (3) NSSC Survey Center,
USDA/NRCS, Federal Building, Room 152 - Mail Stop 34, 100 Centennial Mall
North, Lincoln, NE 68508-3866

The historic grasslands of North America stretch from Texas to North Dakota
within the United States, and are a principal agricultural small grain-
producing region over the last Century, i.e., America's "breadbasket".
Across this region, areas of original grassland still exist, undisturbed by
plowing and cultivation, which offer us profiles developed in response to
the plant cover and climate of the past several thousand years.We sampled
14 of these native grassland sites over a wide area extending over 13œ of
latitude and 10œ of longitude. After removal of soil carbonates, we
obtained radiocarbon ages on soil organic carbon (SOC) by soil profile
horizon (ranging from 5 to 40 cm in thickness) to an average depth of 1.9±
0.3 m and analyzed the stable-carbon isotope composition (.13C) of each of
these samples. In most cases, SOC in surface soils is modern or post-bomb
with respect to radiocarbon content, and the corresponding .13C is highly
correlated to the .13C signature of live vegetation at the site. Usually
radiocarbon age of SOC increased with depth, in some cases with ages below
1.5 m in excess of 10,000 years, although occasionally a reversal occurred
perhaps related to erosion-deposition effects and paleodrainage. The SOC
.13C generally became more negative with depth.We have examined the
patterns of .13C variation with depth (age) to infer changes in proportions
of past C3 and C4 vegetation, which can shift in response to past climate
conditions. A warming climate is probably indicated from ~12,000 yBP to
~2000 yBP.

SOURCES OF SILICATE DUST IN TERRA ROSSA SOILS AND SURFICIAL DEPOSITS,
SOUTHEAST SOUTH AUSTRALIA
BESTLAND, Erick A., FORBES, Matthew S.
Earth Sciences (SoCPES), Flinders University, GPO Box 2100, Adelaide, 5001,
Australia, Erick.Bestland@Flinders.edu.au

Strontium isotopes (Sr87/86) combined with mineralogy and mass balance
geochemistry are used to trace silicate material from possible regional
sources through local playa-lunette systems and ultimately into Terra Rossa
soils in the Southeast of South Australia. Results show good correspondence
between the clayey Terra Rossa soil horizons and nearby lunette deposits,
indicating that the soil is largely derived from silt and clay blown-off
this extensive playa system. The silicate material in the underlying
limestone is easily discounted as a source for the Terra Rossa soil through
a combination of mass balance geochemistry and comparisons of strontium
isotopes. A variety of potential local to regional sources for the fine-
grained material in the lunette-playa system are possible. These include
Quaternary basaltic volcanics, early Paleozoic granitic rocks, early
Paleozoic syn-tectonic shale-sandstone sequences, late Precambrian shale-
sandstone sequences, Murray River mud, and far-travelled dust. The
strontium isotopes and XRD mineralogy strongly indicate the fine-grained
material that is widespread in the lagoons and soils of this district have
a source dominated by the early Palaeozoic shale-sandstone units. Thus, the
deposition in this district over the last million years, just south from
the Murray River mouth, shows local provenance dominating over inputs from
the Murray River. Reasons for this include the abundance and durability of
mica and illite from these syn-tectonic shale-sandstone units as well as
their extensive exposure and ease of weathering. The local volcanic rocks
are of limited aerial extent. The granitic rocks are proximal to the soils
in question but have restricted outcrop distribution. An unexpected finding
is that Murray River mud is not a significant contributor to the
finegrained material. It is possible that Murray River mud is largely
trapped in up-stream floodplains, playas, and yazoo-like streams where a
significant portion is deflated and blown to the east.

PEATLAND: A PROCES-BASED MODEL OF CARBON DIOXIDE AND METHANE FLUXES FROM
PEAT SOILS
VAN HUISSTEDEN, J., VAN DEN BOS, R.M.
Environmental Geosciences, Vrije Universiteit, Faculty of Earth and Life
Sciences, De Boelelaan 1085, Amsterdam, 1081 HV, Netherlands,
ko.van.huissteden@geo.falw.vu.nl

The management of peatlands has a large effect on the carbon balance of
these areas. Since medieval times the coastal peat areas in the Netherlands
have been drained for agriculture. However, plans exist to convert parts of
these peatlands back into wetland nature reserves by raising water levels
again. Since drainage began, the Dutch coastal peat areas became a source
of CO2. On the other hand, raising of the groundwater level may turn these
areas in a source of CH4, which is more effective as a greenhouse gas than
CO2. PEATLAND is a process-based model of CO2 and CH4 emission from peat
soils at various management scenarios. PEATLAND includes CO2 and CH4
production from different soil organic matter reservoirs, including the
peat substrate of the soil. CO2 production is modelled using first order
decomposition rates. The decomposition constants are influenced by the
environmental factors temperature, soil aeration, soil moisture and pH. The
CH4 emission includes production from fresh organic matter, methane
oxidation in the soil, and transport by diffusion, through plant roots and
bubbles. Both submodels are linked to a primary production model. The model
is validated using closed chamber flux measurements at three sites in the
Netherlands. The model results indicate interesting links between CO2 and
CH4 production in cases of a seasonally fluctuating water table. The CH4
production during high water table periods is suppressed by aerobic
decomposition of fresh organic matter reservoirs during low water table
periods. In case of a winter-high, summer-low water table regime CH4 flux
peaks occur in spring and autumn. High CH4 emission only occurs after a
considerable raise of the water table. In some cases this may cause a net
increase of the greenhouse gas flux (expressed in CO2 equivalents) in spite
of a decreased CO2 flux.

SOIL GENESIS RELATED TO MEDIEVAL WARM PERIOD'S CLIMATIC FLUCTUATIONS IN
SOUTHERN PATAGONIA AND TIERRA DEL FUEGO (ARGENTINA). CHRONOLOGICAL AND
PALEOCLIMATIC CONSIDERATIONS
FAVIER-DUBOIS, Cristian M.
CONICET-INCUAPA, ArqueologÌa, Facultad de Ciencias Sociales (UNCPBA),
Avenida del Valle 5737, OlavarrÌa B7400JWI Argentina,
cfavier@coopenet.com.ar.

Geoarchaeological work carried out in five localities in Southern Patagonia
and Northern Tierra del Fuego has demonstrated the presence of a
pedogenesis interval represented by a mollisol, in the upper section of
widespread late Holocene aeolian and colluvial deposits. This soil is
buried at the archaeological sites under study but remains exposed in other
areas of the same landscape. The mollisol's origin and development may
indicate an important change in environmental conditions due to the
stabilization of regional aeolian and colluvial systems at that time.
Furthermore, there are changes in the distribution of the archaeological
record that are linked to this development. Radiocarbon dates on materials
found beneath this soil (maximum ages) and those by OCR (Oxidizable Carbon
Ratio) in the AC horizon (minimum ages) indicate the beginning of its
development around the year 1000 BP. Chronologically, there appears to be a
correspondence between the beginning of the mollisol and the presence of
climatic anomalies in southern Patagonia that coincided with the so-called
Medieval Warm Period. These climatic fluctuations are present in Patagonia
according to dendroclimatic studies.

IS THERE A CHANCE TO RECONSTRUCT HOLOCENE PALAEOCLIMATE DATA USING
COLLUVIAL SOILS?
LEOPOLD, Matthias, VOELKEL, Joerg
Dep. Physical Geography & Soil Science, Univ Regensburg,
Universitaetsstrasse, Regensburg, 93040, Germany,
matthias.leopold@geographie.uni-regensburg.de

In the German literature colluvials are seen as correlated sediments of men
induced processes like clearing, farming, settlement or mining etc. Due to
the long settlement and especially farming history in Southern Germany
(back to the Meso-/Neolithic era 6.000 to 8.000 a BP) they represent a
widely spread geo-archive mainly beeing used for the reconstruction of the
land use history. But futhermore colluvial soils store also the typology
data of the eroded soils and of the processes of their formation as well as
indications of pedogenetic processes which took place after the deposition.
All of these processes are closely related to the climatic parameters and
here especially to the precipitation. So it seems to be obvious to test
these soils on their capability for a Palaeoclimate reconstruction also
because colluvial soils originated in Central Europe in different
settlement eras and therefor probably a time series could be established.
Nevertheless the reconstruction of precipitation proxidata is difficult,
because colluvials must be seen as a syngenetical product of different
parameters like relief, erodibility, field size, farming techniques,
pressure of population, time of usage and climate. During historic time
slices written documents can help to correlate sediment- and soil data with
described weather phenomena. But during prehistoric time slices, which is
by far the longest part of the farming period in Central Europe, it is
shown u.o. through own examples, that the reconstruction of all of the
parameters which control colluvial erosion and sedimentation, is not
possible at present. It would be the precondition for a reconstruction of
climate data or for the correlation with already existing Holocene climate
archives. Also based upon our own investigations, colluvials which
doubtlessly include climatic information, can not be used for the
reconstruction of palaeoclimate data at present.

COMPOSITIONAL STUDY OF THE LAST INTERGLACIAL PALEOSOL S1 LOESS MINERALS
FROM CHINESE LOESS PLATEAU USING SYNCHROTRON X-RAY DIFFRACTION (XRD) AND
SYNCHROTRON X-RAY ABSORPTION NEAR EDGE STRUCTURE (XANES)
FENG, Huan1, POPE, Gregory A.2, FENG, Zhaodong3, CIFELLI,Christen E.4,
LANZIROTTI, Anthony5
(1) Dept. of Earth & Environmental Studies, Montclair State Univ, Upper
Montclair, NJ 07043, fengh@mail.montclair.edu, (2) Earth & Environmental
Studies, Montclair State Univ, Upper Montclair, NJ 07043, (3) Dept. of
Earth and Environment Studies, Montclair State Univ, Upper Montclair, NJ
07043, fengz@mail.montclair.edu, (4) Department of Earth and Environment
Studies, Montclair State Univ, Upper Montclair, NJ 07043, (5) Consortium
for Advanced Radiation Sources, The Univ of Chicago, Chicago, IL 60637

This study focuses on the paleosol S1 formed during the last interglacial
(approximately from 125,000 to 75,000 years before present) in the Chinese
Loess Plateau in an attempt to microscopically examine the mineralogical,
chemical compositions, and redox state of iron-bearing phases. These
microscopic properties will help us answer essential questions regarding
the last interglacial climatic conditions under which the paleosol S1 was
developed in the Chinese Loess Plateau. Understanding the S1 soil-forming
processes and the processes-related East Asian Monsoon is critical to both
improving the soil-related climatic proxies and providing regional
information in reconstructing the global interglacial paleoclimate. In this
study, we analyzed S1 samples from different geographic and bioclimatic
zones with the hope that the geographic differentiation and bioclimatic
dependency of the last interglacial paleosol S1 can be traced using
synchrotron microbeam x-ray diffraction (XRD) and Synthrotron x-ray
absorption near edge spectroscopy (XANES).We will present the results of
the loess internal structure and mineral composition in a micrometer-length
scale.

THE S1 PALEOSOL ENVIRONMENTAL RECORD INTERPRETED THROUGH SOIL DEVELOPMENT
AND WEATHERING INDICES
POPE, Gregory A.1, FENG, Zhaodong2, GORRING, Matthew L.3, OLSON, Carolyn4
(1) Dept. of Earth and Environmental Studies, Montclair State Univ, Upper
Montclair, NJ 07043, popeg@mail.montclair.edu, (2) Dept. of Earth and
Environment Studies, Montclair State Univ, Upper Montclair, NJ 07043,
fengz@mail.montclair.edu, (3) Dept. of Earth and Environmental Studies,
Montclair State University, Upper Montclair, NJ 07043, (4) National Soil
Survey Laboratory, National Resource Conservation Service, 100 Centennial
Mall North, Lincoln, NE 68508

Pedogenic and weathering processes are intricately related to paleoclimate
evidence in loess. Soil processes (clay formation and translocation,
carbonate concentration, and iron alteration and translocation) are all
tied to weathering reactions that occur in the soil. Proxy indicators
reveal environmental change, but the environment itself may alter the proxy
indicators. Is the paleoclimate evidence biased by inherent complexity? One
way to address this quandary is to investigate specific soil formation and
weathering processes. This study applies quantified soil development
indices and weathering indices and compares these against existing climate
proxy indicators for the S1 Paleosol in the Chinese Loess Plateau. Six
field locations were surveyed and sampled in two northwest-to-southeast
transects in the Chinese Loess Plateau. A range of field data
(horizonation, color, texture, structure, carbonate morphology) was used to
calculate a profile development index modified from Harden's (1982). The
index was applied to the entire S1 profile at each location, and to
segments within the S1 profile. Samples were taken for chemical analysis to
establish leaching trends. Inductively coupled plasma optical emission
spectrometry (ICP-OES) achieved composition for 10 major elements of
samples taken at 10 and 20 cm intervals in the profile.Weathering and
leaching indices calculat- ed ratios of more mobile to more stable
elements. These indicated degrees of chemical weathering at specific
horizons, but also indicated translocation and enrichment of certain
elements. Profile development indices demonstrated a separation of paleosol
units within the S1 stratum at the cool/dry (northwest) ends of the
sampling transect, but verified significant soil welding toward the
warm/moist ends of the transect (southeast). Soil welding has been
suggested as a complicating factor in the use of key locations as primary
paleoclimate records.Weathering and leaching indices indicate a higher
degree of chemical activity within the paleosol layers, separated by less
elemental translocation in intervening loess subunits. Chemical weathering
supports the soil welding evidence. In fact, chemical alteration is evident
as translocation into the lower L2 loess stratum immediately below the S1
paleosol sequence.

LINKING THE LOESS - PALEOSOL RECORD OF PLEISTOCENE CLIMATE IN SERBIA WITH
THE EXPANDING CENTRAL EUROPEAN AMINOSTRATIGRAPHY
OCHES, Eric A.1, MARKOVIC, Slobodan B.2, MCCOY, William D.3, STEVENS,
Thomas3, GAUDENYI, Tivodar2, JOVANOVIC, Mladjen2, and WALTHER, Richard1
(1) Department of Geology, Univ of South Florida, 4202 E. Fowler Ave. -
SCA528, Tampa, FL 33620, oches@chuma1.cas.usf.edu, (2) Quaternary Research
Center, Institute of Geography, Univ of Trg Dositeja, Obradovica 3, 21000
Novi Sad, Yugoslavia, (3) Department of Geosciences, Univ of Massachusetts,
Amherst, MA 01003-5820

Numerous loess-paleosol sections have been investigated along Fruska Gora
in Vojvodina, Serbia, and a detailed paleoclimate record for the mid to
late Pleistocene is emerging for southcentral Europe. In order to test
regional stratigraphic correlations and correlate with loess sequences
studied elsewhere in central Europe, we sampled fossil gastropod shells
from loess units and measured D/L amino acid ratios in an effort to expand
our evolving European aminostratigraphy into the Serbian loess region.
Stari Slankamen, the longest continuous section that we have sampled,
includes eight interglacial paleosols and intervening loess units recording
alternating warm-moist and cool-dry climate oscillations.We also sampled
loess-paleosol sections at Ruma, Petrovaradin, Irig, Miseluk, Kula, and
Titel. Gastropods sampled include the genera Helicopsis, Trichia, Pupilla,
and Succinea. Using reverse-phase liquid chromatography, we measured D/L
ratios in 10 amino acids. Our analysis and interpretations focus on D/L
aspartic acid, glutamic acid, valine, phenylalanine, and
allisoleucine/isoleucine ratios (aIle/Ile). The range of racemization rates
exhibited by these amino acids allows us to optimize resolution for
different time periods. According to the present chronostratigraphic model,
loess L1 and paleosol S1 were formed during glacial cycle B, corresponding
with marine oxygen-isotope stages (MIS) 2-5. Horizons within L2 and S2
correspond with glacial cycle C and MIS 6 and 7, respectively. S2 is a
double paleosol and is correlated with the Hungarian BD paleosol pair on
the basis of racemization data. Loess and paleosol units L3 and S3
correlate with glacial cycle D and MIS 8 and 9, respectively. Older units
in the sequence are similarly correlated with the Hungarian
aminostratigraphy, although few outcrops are available for sampling and
comparing data from stratigraphically lower units. Present-day ground
temperatures in loess of Hungary and Serbia show a significant increase in
temperature from the northwest to the southeast. Mean annual temperature at
one-meter depth rises from 10.5 œC near Budapest to 13.5 C in parts of
Vojvodina. This increase in temperature explains the more rapid rate of
racemization and the higher D/L ratios in loess of Vojvodina relative to
the equivalent age loess units in Hungary.





THE AGE OF PERIGLACIAL SLOPE DEPOSITS AND SOILS OF LATE GLACIAL TIME IN THE
CENTRAL EUROPEAN HIGHLANDS
VOELKEL Joerg and LEOPOLD, Matthias
Dep. Physical Geography & Soil Science, Univ Regensburg,
Universitaetsstrasse, Regensburg, 93040, Germany,
joerg.voelkel@geographie.uni-regensburg.de

The Central Highlands of Germany were largely unglaciated during the WÝrm,
and were subject to humid-cold periglacial climate. Extensive sheets of
periglacial slope deposits partially fill the valley bottoms and mantle the
mountains, foreland hills. Genesis and youngest age of the periglacial
slope deposits is used as an important palaeoclimatic indicator. Although
there is general agreement on the tripartite division of their
lithostratigraphy, there is debate on the actual age of these deposits. The
debate comes about because of conflicting interpretations of the efficacy
of the Laacher See Tephra as a chronological marker. When the Plinian
eruption of the Laacher See volcano occurred in AllerÆd time its tephra
plume extended over parts of the Central Highlands. Today, the tephra is
often found as scattered shards intermingled with the periglacial deposits
and, hence, some authors have assigned the periglacial slope deposits to a
Younger Dryas age. The fact that the Laacher See tephra is found mixed with
the periglacial slope deposits is, from the stratigraphical point of view,
not a sufficient reason to conclude that the deposits are of the same age.
It is in this context that our dates from several bogs whole over the
Central European Highlands are critical in constraining the age of the
periglacial slope deposits. In the case of Bavarian Forest peats just above
the underlying periglacial slope deposits yielded radiocarbon dates which
date the Upper Head, at a minimum, Older Dryas which is also consistent
with palynological assignation of those bogs to the chronological Pollen
Zone Ia. In the Fichtelgebirge the minimum age of the Upper Head is also
Older Dryas, dated by radiocarbon. Palynological work assigned these bogs
to the AllerÆd. In the Harz, all the palynological data show that the bogs
were initiated during the Younger Dryas itself. Therefore, the Upper Head
below the bogs has to be older than AllerÆd. In the RhÆn bogs, the Laacher
See Tephra is either found within the peat or lying as an undisturbed layer
on the top of the Upper Head. The RhÆn bog itself was growing during the
BÆlling. Hence, nowhere in our study sites can the Upper Head be of Younger
Dryas age as presumed in the literature since 40 years.