Mean Annual Temperature

Elucidating the role of pyrogenic carbon (C pyr) as a global pool for CO 2 sequestration in temperate ecosystems requires information on the contribution of C pyr to soil organic carbon (SOC) across different climatic regions. We investigated the effect of climate and basic soil properties on the accumulation of C pyr in surface soils across the native North American prairies. Topsoil samples (0-10 cm) of 18 native grassland sites along temperature and precipitation transects from central Saskatoon, Canada, to south Texas, USA, were analyzed for benzenecarboxylic acids as molecular markers for C pyr after nitric acid oxidation in the bulk soil (<2 mm), clay-(<2 mm) and silt-sized (2-20 mm) separates. C pyr contributed between 4 and 18% to SOC, the major proportions of C pyr being mostly found in the clay and silt fractions. C pyr in soil did not correlate with basic inorganic soil properties such as pH or clay content, but it increased significantly as SOC contents increased (r 2 = 0.78; P < 0.001). Obviously, C pyr co-accumulated with dead biomass. Since this accumulation depends on climate, also C pyr contents in soil depend on climate and may be predicted by the logarithm of the ratio of mean annual temperature (MAT) to mean annual precipitation (MAP) (P < 0.05). We conclude that the natural potential of soils to sequester C pyr reflects both, (1) higher C pyr production at sites with high plant biomass in moist climates, and (2) lower C pyr residence time at soils acting as a CO 2 source in warm climates.

Nitrogen (N) and phosphorus (P) and N: P ratio in terrestrial plants and the patterns at a large geographical scale are an important issue in ecological stoichiometry. In particular, it is essential to know that for a single species, how the N: P stoichiometry varies with climatic ...

Biological nitrogen fixation (BNF) as a result of the legumes-rhizobia symbioses is the main source of nitrogen in organic farming systems. Lucerne (Medicago sativa L.), used as green manure or as forage legume, is important on arable farms under dry site conditions. In a field experiment on organically managed agricultural fields, we examined the impacts of the utilisation system (harvested = forage production versus mulched = green manure) and the crop composition (pure lucerne crops versus lucerne-grass mixtures) on yield, biological nitrogen fixation (BNF), soil inorganic N content, N balance and water consumption of autumn-cultivated lucerne crops. The study was conducted at the University of Natural Resources and Applied Life Sciences, Vienna, in eastern Austria-a region characterized by pannonian site conditions (9.8 8C mean annual temperature, 545 mm average total precipitation) and stockless farming systems. Our results indicate that the utilisation system and the crop composition had no marked influence on above-and below-ground dry matter (DM) and N yield, soil inorganic N contents, BNF, or water use efficiency of lucerne. The level of symbiotically fixed N 2 in harvested lucerne was 89-125 kg N ha À1 (27-33% Ndfa = nitrogen derived from atmosphere) in the first year and 161-175 kg N ha À1 (47-49% Ndfa) in the second year of the study. The high soil inorganic N supply in the first year increased the N uptake from soil by lucerne and led to a reduced BNF. Under the dry and unfavourable conditions in both study years, the nitrogen release from the legume mulch was retarded and BNF in mulched lucerne was not reduced. Assuming low gaseous N losses by mulching (15-30 kg N ha À1 ), the green manure system reached a positive N balance (+137 to +186 kg N ha À1 ) for the subsequent crops because abundant residues remained on the field. #

Recent research on slope processes and weathering on Marion Island has highlighted distinctive attributes of the maritime Subantarctic periglacial environment, compared to other periglacial environments. This is reflected morphologically by sorted stripe characteristics and stratified solifluction forms, but the wind factor and low diurnal temperature range also results in differences with other diurnal frost environments. Its hyper-maritime setting at low mean annual temperatures results in very high frost cycle frequencies, with associated effectiveness in surface sediment transport and patterned ground development. In addition, a high frequency of wetting and drying cycles is observed in rocks. Small seasonal temperature ranges and steep temperature profiles indicate a high sensitivity to climate change in the Subantarctic, as reflected in a rich relict periglacial record on most islands. This sensitivity appears absent in high tropical environments of low annual temperature range. D

All species in the genus Cyperus (Cyperaceae) that occur in temperate eastern North America were assigned to either the C 3 or C 4 photosynthetic pathway using leaf anatomical characteristics and stable carbon isotope ratios. Of the 39 species in the study area, 32 had C 4 photosynthesis while 7 had C 3 . The numbers of C 3 , C 4 , and total Cyperus species were significantly and positively correlated with both summer precipitation and mean annual temperature. However, the proportional abundance of C 4 species within Cyperus was not significantly related to either climatic variable. The highest Cyperus diversity was found on the Atlantic Coastal Plain, a pattern that remained after climatic differences between regions were accounted for. All the C 3 species and the majority of the C 4 species were restricted to wetlands or damp soil habitats; 13 of the 32 C 4 species occurred in dry, sandy habitats. Given that the C 3 pathway is ancestral in the genus Cyperus, it appears that C 4 photosynthesis evolved in a wetland context for this genus. We suggest that the high nitrogen use efficiency associated with the C 4 pathway is largely responsible for the evolution and ecological success of C 4 Cyperus species in infertile, temperate wetlands.

Introduction The Oslofjord region in SE-Norway has been subject to steady glacio-isostatic uplift during the whole Holocene. The final retreat of the ice at the termination of the last glacial took place in this area between 13,900 (retreat from Hvaler ice-marginal ridge) and 11,500 years BP (retreat from Ski ice-marginal ridge). Since then, the area has been characterized by continuous

Despite uncertainty in all levels of analysis, recent and long-term changes in our climate point to the distinct possibility that greenhouse gas emissions have altered mean annual temperatures, precipitation and weather patterns. Modeling efforts that use doubled atmospheric CO 2 scenarios predict a 1-78C mean global temperature increase, regional changes in precipitation patterns and storm tracks, and the possibility of ''surprises'' or sudden irreversible regime shifts. The general effects of climate change on freshwater systems will likely be increased water temperatures, decreased dissolved oxygen levels, and the increased toxicity of pollutants. In lotic systems, altered hydrologic regimes and increased groundwater temperatures could affect the quality of fish habitat. In lentic systems, eutrophication may be exacerbated or offset, and stratification will likely become more pronounced and stronger. This could alter food webs and change habitat availability and quality. Fish physiology is inextricably linked to temperature, and fish have evolved to

Aim To describe the geographical pattern of mean body size of the non-volant mammals of the Nearctic and Neotropics and evaluate the influence of five environmental variables that are likely to affect body size gradients. Location The Western Hemisphere. Methods We calculated mean body size (average log mass) values in 110 × 110 km cells covering the continental Nearctic and Neotropics. We also generated cell averages for mean annual temperature, range in elevation, their interaction, actual evapotranspiration, and the global vegetation index and its coefficient of variation. Associations between mean body size and environmental variables were tested with simple correlations and ordinary least squares multiple regression, complemented with spatial autocorrelation analyses and split-line regression. We evaluated the relative support for each multiple-regression model using AIC. Results Mean body size increases to the north in the Nearctic and is negatively correlated with temperature. In contrast, across the Neotropics mammals are largest in the tropical and subtropical lowlands and smaller in the Andes, generating a positive correlation with temperature. Finally, body size and temperature are nonlinearly related in both regions, and split-line linear regression found temperature thresholds marking clear shifts in these relationships (Nearctic 10.9 ° C; Neotropics 12.6 ° C). The increase in body sizes with decreasing temperature is strongest in the northern Nearctic, whereas a decrease in body size in mountains dominates the body size gradients in the warmer parts of both regions. Main conclusions We confirm previous work finding strong broad-scale Bergmann trends in cold macroclimates but not in warmer areas. For the latter regions (i.e. the southern Nearctic and the Neotropics), our analyses also suggest that both local and broad-scale patterns of mammal body size variation are influenced in part by the strong mesoscale climatic gradients existing in mountainous areas. A likely explanation is that reduced habitat sizes in mountains limit the presence of larger-sized mammals.

Alterations in VO(2) or VCO(2) are amongst the more polemical physiological adaptations ascribed to insects. Generally, metabolic rate is thought to be lowered in response to arid conditions, and elevated in species from cold environments compared to their more temperate relatives. However, most studies have rarely addressed the influence of both environmental factors in unison. To this end, standard metabolic rate and its temperature dependence were measured (at 4 degrees C intervals from 16 to 32 degrees C) in six Scarabaeus dung beetle species (three flightless, three volant) from a variety of habitats (warm, arid to cool, mesic) in southern Africa using flow-through respirometry. Mass specific VCO(2) varied from 0.0158 ml g(-1) h(-1) at 16 degrees C to 0.1839 ml g (-1) h(-1) at 32 degrees C. The slopes of the rate temperature curves were similar for all species (Q(10)s of 2.14-2.84), although the intercepts differed significantly in the direction (warm arid to cool mesic): S. gariepinus&amp;amp;amp;lt;S. hippocrates&amp;amp;amp;lt;S. striatum&amp;amp;amp;lt;S. galenus&amp;amp;amp;lt;S. rusticus&amp;amp;amp;lt;S. westwoodi. General linear models were fitted to the VCO(2) data with treatment temperature, wing status, mean annual rainfall and mean annual temperature as the independent variables. For all six species, the best fit model included treatment temperature and wing status only. Flightless species had significantly lower VCO(2)s than did winged ones. Amongst the flightless species, S. gariepinus, from the driest area, had the lowest VCO(2). Among the winged species it was impossible to determine whether environmental temperature or water availability were most important in influencing VCO(2); both were significant. We conclude that investigations of metabolic rate modulation, and especially metabolic cold adaptation, in insects must take both temperature and water availability into account.

Araceae is one of the largest herb families in tropical America, but its patterns of diversity and endemism are poorly known. We used predictive distribution modelling in GIS to study Araceae richness on a landscape scale in Ecuador. Modelling was based on georeferenced herbarium collections with humidity and mean annual temperature as climatic variables. Variation partitioning using multiple regression showed that humidity and altitude were main factors in explaining Araceae diversity patterns. Endemism was less well explained by present climatic factors. Unlike common diversity patterns of herbs or epiphytes, Araceae richness was highest in the eastern (Amazon) lowland rain forest with a secondary centre on the Andean foothills of northwestern Ecuador. The peak in endemism was on the western slopes of the Andes, corresponding to areas that have been severely affected by human activities and deforestation. Eastern lowland (Amazonian) forests were poor in endemic Araceae.

Patterns of genetic variation in Cordia africana, a tropical timber species, were evaluated at the population level. Bulk seed samples were collected from six natural populations in Ethiopia and examined for variations in seed morphometric traits, seed germination, and seedling growth at nursery stage. Analysis of variance revealed significant differences among provenances in all studied attributes except root collar diameter after 4 months of growth. The provenance effect, as determined by broad sense heritability, was 71–98% for seed morphometric traits, 80% for germination capacity, 42% for germination energy, 57–58% for seedling height and 3–13% for root collar diameter. Seed weight showed a significant positive correlation with altitude and negative correlation with mean annual temperature of seed origin. Germination energy was significantly correlated with longitude and mean annual rainfall. Seedling parameters and geo-climatic variables of seed origin were fairly correlated. A significant intercharacter correlation was found between seed length and seed weight, between root collar diameter at the age of 4 months and seed length and weight, as well as between seedling height after 4 and 8 months of growth. It can be concluded that the observed patterns of variation will have implications for genetic resources conservation and tree improvement.

Physically-and biochemically-distinct fractions of soil organic matter (SOM) can be separated by density to yield: (i) low-density plant detritus fraction easily separable from soil minerals (f-LF), (ii) low-density materials strongly associated with minerals (m-LF), and (iii) high-density fraction (HF) rich in microbiallyprocessed organic matter strongly associated with minerals. The factors controlling the pool size and chemistry in these fractions, especially those in m-LF, are unclear. We examined the influence of climate and parent material on SOM in these fractions using two sets of forest soils (0-10 cm mineral horizon) developed from contrasting parent materials (metasedimentary vs. ultrabasic igneous rock) along an altitudinal gradient in Mt. Kinabalu, Borneo. From 700 m to upper altitudes (1700, 2700 m), where mean annual temperature decreases from 24 to 12°C with roughly constant rainfall, surface soil C stocks on both parent materials increased from 2.6-2.8 to 5.4-7.5 kg m − 2 with progressively greater proportions in m-LF and, to less extent, fresher plant detritus fractions. In HF, C and N concentrations increased with altitude though their stocks were roughly constant due to progressively lower bulk density. Labile C assessed by laboratory incubation of bulk soils correlated better with C concentrations in the two LF pools than in HF, especially at the lowest altitude where most SOM is strongly associated with minerals as HF. These results suggest that LF pools are more labile and more sensitive to altitude-induced, climate differences as compared to the HF pool that is protected by the mineral matrix. The C:N ratios of HF on metasedimentary rock increased with altitude (11 to 17) while those on ultrabasic rock remained essentially constant (14-15), implying interactive influence of altitude and parent material on stoichiometry. Unusually high C:N and alkyl-C in m-LF were found in mid-altitude soils, suggesting selective preservation of inherently recalcitrant materials in addition to, or instead of, mineral coating or aggregate occlusion of partially-degraded LF by microbial metabolites.

As the planet cooled from peak warmth in the early Cenozoic, extensive Northern Hemisphere ice sheets developed by 2.6 Ma ago, leading to changes in the circulation of both the atmosphere and oceans. From w2.6 to w1.0 Ma ago, ice sheets came and went about every 41 ka, in pace with cycles in the tilt of Earth's axis, but for the past 700 ka, glacial cycles have been longer, lasting w100 ka, separated by brief, warm interglaciations, when sea level and ice volumes were close to present. The cause of the shift from 41 ka to 100 ka glacial cycles is still debated. During the penultimate interglaciation, w130 to w120 ka ago, solar energy in summer in the Arctic was greater than at any time subsequently. As a consequence, Arctic summers were w5 C warmer than at present, and almost all glaciers melted completely except for the Greenland Ice Sheet, and even it was reduced in size substantially from its present extent. With the loss of land ice, sea level was about 5 m higher than present, with the extra melt coming from both Greenland and Antarctica as well as small glaciers. The Last Glacial Maximum (LGM) peaked w21 ka ago, when mean annual temperatures over parts of the Arctic were as much as 20 C lower than at present. Ice recession was well underway 16 ka ago, and most of the Northern Hemisphere ice sheets had melted by 6 ka ago. Solar energy reached a summer maximum (9% higher than at present) w11 ka ago and has been decreasing since then, primarily in response to the precession of the equinoxes. The extra energy elevated early Holocene summer temperatures throughout the Arctic 1e3 C above 20th century averages, enough to completely melt many small glaciers throughout the Arctic, although the Greenland Ice Sheet was only slightly smaller than at present. Early Holocene summer sea ice limits were substantially smaller than their 20th century average, and the flow of Atlantic water into the Arctic Ocean was substantially greater. As summer solar energy decreased in the second half of the Holocene, glaciers reestablished or advanced, sea ice expanded, and the flow of warm Atlantic water into the Arctic Ocean Quaternary Science Reviews 29 diminished. Late Holocene cooling reached its nadir during the Little Ice Age (about 1250e1850 AD), when sun-blocking volcanic eruptions and perhaps other causes added to the orbital cooling, allowing most Arctic glaciers to reach their maximum Holocene extent. During the warming of the past century, glaciers have receded throughout the Arctic, terrestrial ecosystems have advanced northward, and perennial Arctic Ocean sea ice has diminished.

Belowground carbon allocation (BCA) in forests regulates soil organic matter formation and influences biotic and abiotic properties of soil such as bulk density, cation exchange capacity, and water holding capacity. On a global scale, the total quantity of carbon allocated belowground by terrestrial plants is enormous, exceeding by an order of magnitude the quantity of carbon emitted to the atmosphere through combustion of fossil fuels. Despite the importance of BCA to the functioning of plant and soil communities, as well as the global carbon budget, controls on BCA are relatively poorly understood. Consequently, our ability to predict how BCA will respond to changes in atmospheric greenhouse gases, climate, nutrient deposition, and plant community composition remains rudimentary. In this synthesis, we examine BCA from three perspectives: coarse-root standing stock, belowground net primary production (BNPP), and total belowground carbon allocation (TBCA). For each, we examine methodologies and methodological constraints, as well as constraints of terminology. We then examine available

By explicitly linking process to form, landsystem models developed in modern environments provide powerful tools for the reconstruction of past environments from the sedimentological and geomorphological record. Some landform characteristics, however, may originate by more than one process (equifinality), so although a particular depositional model may “fit” the data, it is not necessarily the correct one. Here, we critically examine

Recent research on slope processes and weathering on Marion Island has highlighted distinctive attributes of the maritime Subantarctic periglacial environment, compared to other periglacial environments. This is reflected morphologically by sorted stripe characteristics and stratified solifluction forms, but the wind factor and low diurnal temperature range also results in differences with other diurnal frost environments. Its hyper-maritime setting at low mean annual temperatures results in very high frost cycle frequencies, with associated effectiveness in surface sediment transport and patterned ground development. In addition, a high frequency of wetting and drying cycles is observed in rocks. Small seasonal temperature ranges and steep temperature profiles indicate a high sensitivity to climate change in the Subantarctic, as reflected in a rich relict periglacial record on most islands. This sensitivity appears absent in high tropical environments of low annual temperature range. D

An ensemble of regional climate model (RCM) runs from the EU HighNoon project are used to project future air temperatures and precipitation on a 25 km grid for the Ganges basin in northern India, with a view to assessing impact of climate change on water resources and determining what multi-sector adaptation measures and policies might be adopted at different spatial scales.

Morocco is located between the arid regions of the western Sahara and the moderate Mediterranean and Atlantic regions. Landscape types reach from flat areas in the north-western part to high-mountain areas in the Atlas and Rif. Therefore, we can find a large variety of climates ranging from moderate humid and subhumid climates at the northern slope of the High Atlas over mountain climates to semiarid and arid climates south of the Atlas. In this tension field, agricultural production and local economy depend very much on water availability, and thus, mainly on rainfall variability. In the past, periods of successive dry years have repeatedly shown the vulnerability to water scarcity, which results in threatened livelihoods of farmers and nomad families living from pasturing. This leads to a stream of migrants heading towards the large cities at the Moroccan coast and even to Europe. In order to counteract the peril of water scarcity, regional planning greatly benefits from information on future climate variability. Of course, the assessment of future climate scenarios in this very heterogeneous region is still a challenge for the climate research community. In this study, the actual state of climate research in IMPETUS West-Africa with respect to rainfall and temperature variability and of research on future climate scenarios is illustrated. We start with an overview of available information from observational data and a few remarks on their quality. In the second part, results of regional climate modelling (RCM) are discussed with respect to future climate variability especially in regions south of the Atlas Mountains, where the water stress is clearly the limiting factor of agricultural production.

Here we developed a composite pollen-based record of altitudinal vegetation changes from Lake Fúquene (5 • N) in Colombia at 2540 m elevation. We quantitatively calibrated Arboreal Pollen percentages (AP%) into mean annual temperature (MAT) changes with an unprecedented ∼60-year resolution over the past 284 000 years. An age model for the AP% record was constructed using frequency analysis in the depth domain and tuning of the distinct obliquity-related variations to the latest marine oxygen isotope stacked record. The reconstructed MAT record largely concurs with the ∼100 and 41-kyr (obliquity) paced glacial cycles and is superimposed by extreme changes of up to 7 to 10 • Celsius within a few hundred years at the major glacial terminations and during marine isotope stage 3, suggesting an unprecedented North Atlantic -equatorial link. Using intermediate complexity transient climate modelling experiments, we demonstrate that ice volume and greenhouse

What circulation pattern drove Southern Alps glacial advances at w21 ka? Late 20th century glacial advances in New Zealand are commonly attributed to a dual precipitation increase and cooler than normal temperatures associated with enhanced westerly flow that occur under synoptic pressure patterns termed 'zonal' regimes . But was the circulation pattern that supported major Southern Alps glacial advances during the global LGM similar to the modern analog? Here, a Regional Climate Regime Classification (RCRC) time slice was used to infer past circulation for New Zealand during the LGM at w21 ka. Palaeoclimate information that supported the construction of the w21 ka time slice was derived from the NZ-INTIMATE Climate Event Stratigraphy (CES), one new Auckland maar proxy record, and additional low-resolution data sourced from the literature.

There are distinct relationships among the anatomy of wood, the morphology of leaves, and the climate in which woody plants are growing. The relationships between leaf morphological characters and climate have been known for many years, but wood characters as climate indicators are less well studied. In this article, we use measurements of wood anatomy and leaf morphology from woody

Biomass partitioning is an important variable in terrestrial ecosystem carbon modeling. However, geographical and interannual variability in f BNPP , defined as the fraction of belowground net primary productivity (BNPP) to total NPP, and its relationship with climatic variables, have not been explored. • Here we addressed these issues by synthesizing 94 site-year field biomass data at 12 grassland sites around the world from a global NPP database and from the literature.

This study compares the CH 4 fluxes from two arctic wetland sites of different annual temperatures during 2004 to 2006. The PEATLAND-VU model was used to simulate the emissions. The CH 4 module of PEATLAND-VU is based on the Walter-Heimann model. The first site is located in northeast Siberia, Indigirka lowlands, Kytalyk reserve (70 • N, 147 • E) in a continuous permafrost region with mean annual temperatures of −14.3 • C. The other site is Stordalen mire in the eastern part of Lake Torneträsk (68 • N, 19 • E) ten kilometres east of Abisko, northern Sweden. It is located in a discontinuous permafrost region. Stordalen has a sub arctic climate with a mean annual temperature of −0.7 • C. Model input consisted of observed temperature, precipitation and snow cover data.

Soil carbon (C) and total N stocks and turnovers were investigated in five vegetation types and following deforestation and conversion of each vegetation types into arable lands along a 37-km elevation transect in southern highlands of Ethiopia. The elevation transect spanned five different eco-climatic zones from semiarid to cool sub-Afroalpine range, each with different vegetation type. Soil C and total N stocks in the upper 0.60 m mineral soil under the natural vegetations varied from 40.3 Mg C ha À 1 and 5.3 Mg N ha À 1 at the semiarid Acacia woodland (AWL) eco-climatic zone to 234.6 Mg C ha À 1 and 20.2 Mg N ha À 1 at the humid Podocarpus falcatus forest (PFF) eco-climatic zone, respectively. This trend was directly proportional to the mean annual precipitation and inversely proportional to the mean annual temperature prevailing along the elevation gradient. The soils of the farmlands had significantly lower soil C and total N stocks than the soils under the natural vegetations. Losses of soil C and total N from the upper 0 -10 cm soil depth following conversion of the natural vegetations to farmlands were highest at the humid PFF eco-climatic zone and lowest at the semiarid AWL eco-climatic zone. The average rates of soil C losses ranged between 2.0% and 3.0% per annum in the sub-humid to humid eco-climatic zones and 0.5 -1.0% per annum in the semiarid lowland or the cool sub-Afroalpine eco-climatic zones. The results revealed the existence of considerable differences, as large as 191.7 Mg C ha À 1 , in soil C stocks along the elevation gradient, and wide range of differences in the rate and amount of soil C and total N losses following conversion of natural vegetations into arable lands. D

The Upper Valdarno (Italy) Plio-Pleistocene continental deposits record the latest uniform subtropical humid conditions and the successive climatic signature of glacial/interglacial cycling. The palynological and sedimentological analyses on the Poggio Rosso alluvial plain sediments reveal two major climatic fluctuations correlated to a glacial/interglacial cycle just before the Plio-Pleistocene boundary. The glacial phase, indicated by the expansion of herbs as well as by ephemeral streams associated with calcareous palaeosols, extends from the base of the succession and culminates close to an impressive mammalian bone accumulation dated at 1.87 Ma. The associated increasing aridity had severe consequences on the faunal communities, inducing the migration of open plain dwellers and the trapping of other residents around a few residual shrinking water bodies. A cooperative Pachycrocuta brevirostris clan acted as regulator of game populations debilitated by drought. Previous research indicates that hyenas were also the major bone accumulators. The following moister and warmer interglacial phase ca 1.83 Ma is documented by arboreal taxa and hydromorphic palaeosols in a floodplain crossed by migrating, perennial, sinuous streams. The Climatic Amplitude Method calculated mean annual temperatures around 12.5-14 C and mean annual precipitation around 800 mm, with a minimum of 400 mm during the glacial phase and 15/16-19 C and 750-1200 mm during the interglacial phase. The reconstruction reveals higher mean annual temperatures and precipitation during the interglacial as compared to the present-day climate. During the glacial, conditions were similar to today's in all but lower precipitation values were reached during the acme drought phase just above the fossiliferous bed. Poggio Rosso documents the ecological consequences the buildup of the Apennine chain had under the effects of the latest Pliocene global climatic changes. It therefore represents one of the first signals of the patchiness that, since then, gradually increased leading to the eventual habitat fragmentation typical of the late Pleistocene landscapes.

The fact of, present is the key of the past, will help us to use paleosols properties as indicators of the ecological characteristics of past time, particularly the paleoclimate. In this respect the micromorphological properties showed to be a very good indicator. Therefore, for investigating of climate change in Ardakan-Yazd plain, Central Iran 9 pedons were digged and described. Yazd has an arid climate with less than 100 mm annual precipitation and more than 22°C mean annual temperature (Aridic-hyper thermic soil moisture and temperature regions, respectively). Based on the morphological and physicochemical analysis Arglic, Calcic and Gypsic diagnostic horizons have been distinguished in these soils. Thin section studied showed that the illuviated form of clay includes, infillings on channel, coating on pendant, on nodules and on grains, at lower depths and also juxtaposed calcite needles on void argillan at upper part of the profiles. Mineralogical result showed fine clay in arglic horizon, too. Considering depth and forms of these pedofeatures, we concluded that, the observed illuviated clays at lower depth must be the result of the more humid climate of the past, where the carbonates have been removed completely as pendant, nodules or coating to considerable depth, following processes, clay has been dispersed and also trans located to these depths. In contrast to these features, the juxtaposed needle calcite at the shallower depth is probably the result of drier climate of today.

Proglacial and subglacial glacitectonic sediments and landforms around the margins of the Strait of Magellan, southernmost Chile, record the advance and retreat of outlet glaciers of the Patagonian ice cap during the last glacial cycle. The spatial arrangement of glacitectonic landforms in the area is inferred to have resulted from the advance of ice lobes with cold-based margins and wet-based interiors. As the ice advanced, subglacial basins were excavated beneath the glacier margins and the eroded material was pushed up into thrust moraines, probably because frozen-bed conditions formed a thermal dam against the free drainage of subglacial meltwater. These ice-marginal glacitectonic landforms were then overridden and streamlined into drumlins and #utes as thicker, wet-based ice passed over the area. Evidence for permafrost near sea level in Patagonia during the last glaciation suggests that mean annual temperatures were several degrees lower than indicated by recent modelling studies. The results indicate that future modelling experiments should incorporate more realistic basal boundary conditions, particularly the presence of a weak deforming layer at the glacier bed, to improve climatic reconstructions of southern South America.

Temperature trend magnitudes at 71 homogenized surface stations with elevations above 2000 m asl in the eastern and central Tibetan Plateau (TP) and 56 grid points from surface NCEP and ERA-40 reanalyses in the TP's vicinity are examined. Both the surface meteorological stations and ERA-40 show general warming trends at the majority of locations, especially in winter. NCEP fails to identify this. Compared with the surface stations, both NCEP and ERA-40 reanalysis data underestimate air temperature trends in the TP, but ERA-40 is better than NCEP. There are no simple linear relationships between elevation and temperature trend magnitudes on an annual or seasonal basis in the surface data or ERA-40, and in NCEP this relationship is inconsistent. Instead there are significant correlations between mean annual and seasonal temperatures and temperature trend magnitudes in the surface dataset and NCEP data (but not ERA-40). We suggest this is due to cryospheric feedback since trends are enhanced when mean annual temperatures are near freezing. The absence of any simple elevation dependency in temperature trends suggests that the rapid warming rate derived from high elevation ice-cores in this region should be interpreted with caution. In addition, more attention should be given to the selection of reanalysis to represent surface climate in the TP, since topographical differences between grid points and stations, and other reanalysis model differences such as surface land schemes, cause differences in trend identification and patterns in this critical region.

Prior investigations suggest that alluvial lowlands of Pangea in the southwestern U.S.A. during the middle to late Triassic experienced an arid to semiarid climate with significant seasonality. Our investigation finds evidence for a global pluvial episode from paleosols in the middle to late Triassic section of eastern Utah. Multi-proxy paleosol evidence is used to quantify rainfall amounts, ambient temperatures and atmospheric CO 2 concentrations and infer associated plant formations related to ecosystem persistence. Rainfall estimates are derived from geochemical molecular weathering ratios; temperature and atmospheric CO 2 levels from stable oxygen and carbon isotopes of pedogenic carbonate, respectively; and ecosystem reconstruction by a combination of climate indexes and paleosol characteristics. Eight pedotypes were identified and include poorly drained aquic Entisols (Fisher), well-drained nonaquic Entisols (Salt Valley), calcic Aridisols (Castle Valley), calcic Inceptisols (Moab), cambic (Ute) and calcic (La Sal) Vertisols, dystric Inceptisols (Kokopeli), and argillic Alfisols (Slickrock). The middle Triassic Moenkopi Formation (Anisian) was dominated by Castle Valley paleosols with mean annual rainfall between 300 and 400 mm and mean annual temperature between 13 and 23 8C (mesic to hyperthermic). Based on these climate indexes and root traces, the associated plant formation was most likely desert shrub or dry woodland. The lower Chinle Formation (Carnian) contains a succession of Ute and La Sal paleosols that changed up-section to Kokopeli, Fisher and Slickrock paleosols. In accordance with geochemical and isotopic signatures from these pedotypes, rainfall amounts initially increased to between 700 and 900 mm, and then to between 1300 and 1400 mm. Temperatures estimated from the La Sal paleosol are approximately 18 8C (thermic) at this time. The lower Chinle marks a transition from dry woodland to open forest that appears to correlate with the formation of the Petrified Forest Member in Arizona. The upper Chinle Formation (Carnian-Norian) reveals a return to semiarid to subhumid conditions and the formation of Castle Valley, Moab and Salt Valley paleosols, all of which appear to have supported desert shrub or dry woodlands. Rainfall amounts decreased to between 400 and 600 mm with temperatures eventually increasing to 29 8C (hyperthermic). Using the paleosol isotopic barometer, atmospheric CO 2 estimates generally correlate with other proxy for the Triassic. The well-developed Alfisols and noncalcareous Inceptisols identified during the Carnian of the lower Chinle correlate with a previously identified global pluvial episode based on sedimentological and marine isotopic evidence, possibly in response to rifting of Pangea. It should not be assumed that the middle to late Triassic in continental alluvial lowlands supported a uniform, semiarid to arid climate, with strong seasonality.

Selected mega- and microfloras from Central and Southern Europe have been analysed for the time interval Tortonian/Pannonian (MN 9–12) with the Coexistence Approach to obtain quantitative palaeoclimate data. The results give a geographically differentiated picture of the Late Miocene climate in the circum-Alpine area. Spatial patterns are presented in maps for mean annual temperature, temperature of the coldest month, temperature of the warmest month, mean annual precipitation, and mean annual range of temperature. The obtained data show an overall warm, humid, and homogenous climate with very low latitudinal and longitudinal gradients; there is no indication of a Mediterranean type of climate. Palaeogeographic influences on climate patterns are evident; the Pannonian Lake caused mild winters and a lower seasonality of temperature in the Pannonian basin.

Natural history museum collections harbour valuable information on species. The usefulness of such data critically depends on the accurate identification of species, which has been challenged by introduction of molecular techniques into taxonomy. However, most collections may suffer from DNA degradation, due to age and/or improper preservation; hence the identification of specimens depends solely on morphological features. This study explores how and to what extent morphological data can help to solve ambiguous taxonomic cases based on selected species concepts and with the use of operational criteria in a species-hypothesis testing procedure. The studied taxon, the Niphargus tatrensis species complex, comprises freshwater subterranean amphipods, distributed across Central Europe, the taxonomic status of which was debated extensively between 1930 and 1960. Using the general species concept, character- and tree-based operational criteria reveal northern and southern diagnosable and exclusive lineages identified here as N. tatrensis Wrześniowski, 1888 and N. scopicauda sp. n., respectively. The remaining populations represent the non-exclusive N. aggtelekiensis Dudich, 1932, which occurs from the eastern Alps to Hungary. In the entire complex, altitudinal distribution is largely limited to areas above 400 m, where the mean annual temperature never exceeds 9°C. Seemingly well-defined distributional ranges of N. tatrensis and N. aggtelekiensis are fragmented in an ecological sense, which raises the question whether two of the three species recognised here actually consist of several unidentified taxa. Morphological similarity between the species, numerous polymorphic features, and the association with cool temperatures lead to a hypothesis in which fragmentation of the ancestral range occurred during post-Pleistocene climate warming, reducing gene flow across lowland populations due to niche conservatism of the ancestral species and/or to invasion of competitive species along the Danube and Drava rivers. The results are discussed regarding how old museum samples are conducive to more detailed molecular-taxonomic and conservation studies.

The Brassington Formation of Derbyshire and Staffordshire in the southern Pennine hills of central England is a succession of sands, gravels and clays preserved within karstic cavities in Carboniferous Limestone. Varicoloured clays and a thin lignite within the uppermost unit (the Kenslow Member) at Kenslow Top Pit near Friden, Derbyshire has yielded abundant pollen, spores and plant remains. The palynoflora

One of Roberts' key contributions was his work demonstrating the applicability of several ecological rules to human populations (Roberts [1953] Am. J. Phys. Anthropol. 11:533-558; [1978] Climate and Human Variability, 2nd ed., Menlo Park, CA: Cummings). His finding that average body weight systematically covaries with mean annual temperature was widely taken as confirmation of Bergmann's rule for humans. More recently his findings on weight and temperature have been extended and confirmed (Ruff [1994] Yrbk. Phys. Anthropol. 37:65-407; Katzmarzyk and Leonard [1995] Hum Biol Council Program Abstracts 132) although the strength of the association may be decreasing when considering more recent surveys (Katzmarzyk and Leonard [1995]). Roberts noted in 1953 that Oceanic populations may be somewhat of an exception to Bergmann's rule, and we propose that Neel's ([1962] Am. J. Hum. Genet. 14:353-362) thrifty genotype model may account for some of the deviation from predicted weights among these populations. We provide an updated version of the thrifty genotype model, suggesting that selection for energetic efficiency may have occurred for some Oceanic populations during the voyaging to and settlement of their island homes. Under conditions of modernization the thrifty genotype may be manifesting as high rates of obesity and NIDDM among Polynesians and Micronesians. First, using measurements of adult male weight from 19 Oceanic populations, we demonstrate the extreme nature of their deviation from predicted weight based on Roberts' regression of weight on mean annual temperature. Next, we regress the deviations from predicted weight on NIDDM prevalence for these 19 populations, producing a highly significant regression (R 2 ϭ 0.46; P Ͻ 0.001), consistent with expectations if the thrifty genotype is responsible for the high weights.

The relationships among wood anatomical characters and climate are examined for 50 wood anatomical features in floras from 37 regions in North America, South America, Africa and Malaysia. Correlations, simple regressions and multiple regressions, were used to develop models for the prediction of climate from wood anatomy. The climate variables considered were: mean annual temperature, mean annual range in temperature, cold month mean temperature, mean annual precipitation, precipitation of the driest month and length of the dry season. Good correlations were found with temperature; poorer correlations with precipitation. The climate variables, especially the temperature-related ones, were best predicted by two or more wood anatomical characters considered together. Characters that we selected to calculate climate variables are: vessels with multiple perforations; spiral thickenings present in the vessels; vessel mean tangential diameter less than 100 μm; fibers septate; rays commonly more than 10 cells wide; rays heterocellular with four or more rows of upright cells; rays storied; axial parenchyma absent or rare; marginal parenchyma present; and wood ring-porous. Models were validated on seven temperate and six tropical sites. Based on these results, a method for determining paleoclimate from fossil wood assemblages is suggested.

The characterisation of 45 Romanian single-strength fruit juices (apples, pears, plums and grapes) collected from different Transylvanian areas by means of stable isotope approach are presented and discussed in this study. We measured 2H/1H, 18O/16O ratios from water juice and 13C/12C from pulp and compared these results with those already reported in the literature for single-strength juices, in order to see how the geographical and climatic conditions of Transylvania and the meteorological peculiarities of the year 2010 influence the isotopic composition of the investigated fruit juices. The δ13C mean values that we found for apple pulp picked up from different Transylvanian areas show slight differences, probably due to the environmental conditions of the plants. No significant correlation either between the variety of apple or the geographical origin and δ13C value was established.

In this paper, we present a continuous time series of the mean annual and seasonal air temperatures for King George Island (KGI), for the period of 1947-1995, combining data from several meteorological stations in the South Shetland Islands. These series are analyzed for trends. The series are also compared with the mean monthly sea ice extent, recorded at 60 • W. The mean annual temperature during this period was −2.8 • C, with a minimum of −5.2 • C, in 1959, and a maximum of −0.8 • C, in 1989. This record shows a warming trend of 0.022 • C a −1 , in the studied time interval, a rise of 1.1 • C in 49 years. Winter shows the most pronounced seasonal warming trend, 0.038 • C a −1 , or 1.9 • C in the period. These trends are better defined than at the Faraday station. Abrupt variations in the mean annual temperature, up to 3.9 • C over three years, have been recorded. Spectral analysis of these time series shows cycles of 5.3 and 9.6 years. A one-month lag is observed between the winter months mean temperatures in KGI and sea ice extent in the 60 • W sector.