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For decades, it has been unclear as to how the world's first cities, in southern Mesopotamia, not only arose in a fluvial environment but also how this environment changed. This paper seeks to understand the long-term fluvial history of the region around Uruk, a major early city, in relation to water-human interactions. This paper applies geomorphological, historical and archaeological approaches and reveals that the Uruk region in southern Mesopotamia had been under the influence of freshwater fluvial environment since the early Holocene. It further demonstrates how canals and long-term human activities since the mid Holocene have been superimposed on the natural river channel patterns. Fieldwork has been conducted to ground-truth features identified applying remote sensing techniques. Five sediment cores were analysed to elucidate palaeoenvironmental changes. Radiocarbon ages for organic samples suggest that the oldest sediment layers, at a depth of 12.5 m, are from the Early Holocene, while results from diatom analyses imply that the whole sediment column was deposited in a freshwater environment. Intensive networks of palaeochannels and archaeological sites within the study area have been reconstructed and these networks have been divided into four different time intervals based on changes in channel courses. The first is from the early 4th to the late 1st millennium BCE; the second is from the late 1st millennium BCE to the middle 2nd millennium CE; the third lasted from after the Islamic period until the 1980s; the fourth is from the 1980s until the present. Key results include evidence for freshwater environments and favourable settlement conditions had already formed by the 8th millennium BCE. The favourable settlement environment resulted in stable (long-lived) canals between the 4th millennium BCE and 1st millennium CE. A significant settlement and irrigation expansion occurred in the early 1st millennium CE. Major abandonment ensued in the late 1st millennium CE and lasted until the mid 2nd millennium CE. [ABSTRACT FROM AUTHOR]

Abstract: The application of phytolith analysis in wetlands to reconstruct the paleoenvironment relies on the research of phytoliths of modern wetland plants. In this paper, 31 selected wetland plant species, belonging to 14 families and 26 genera, were studied. An inventory of phytolith types is provided and type-frequencies are assessed. There are 19 main kinds of phytoliths in this paper: elongate, cross, bilobate, scutiform phytoliths, lanceolate, fusiform phytolith, rondels, achene phytolith, silicified stomata, conical phytoliths, tracheid phytoliths, epidermal cells, trapeziform crenate, cylindrical polylobate, wavy trapezoid, cuneiform bulliform cells, sleeper-type, saddle and silicified hair cells. The taxonomic diagnostic potential of phytoliths (where the silicified stomata are outside) was tested by cluster analysis, which, to a certain extent supported the hypothesis that plant species can be identified on the basis of type, presence and frequency. Conical phytoliths were analyzed separately and results showed that Cyperaceae species can be distinguished by conical phytoliths at the species level. Silicified stomata dimensions were analyzed using one-way ANOVA, which found large disparities in the length and width, and a size category system of silicified stomata dimensions was developed, classifying the major groups into four subgroups. The current study shows that size and shape can be used to assign some of the silicified stomata to their respective genera. The percentage of stomata was also analyzed and the results revealed that there are more stomata in hydrophytes than mesophytes. These results reinforce the utility of using phytoliths as significant indicators for wetland plants and offer the potential of phytolith analysis for paleoenvironment and paleoclimate reconstruction in this region. [Copyright &y& Elsevier]

Abstract: The study of temporal variations in soil intensity has mostly been limited to specific sites. However, it is important for correctly interpreting the stratigraphy and palaeoclimatic significance of loess and palaeosols series to understand the reasons for the spatial variability. More specifically, pedogenetic and sedimentological properties should be evaluated separately. This is particularly well illustrated at the Ruma site (Serbia). In this paper we focus on macroscopic soil characteristics and sediment grain-size properties. The type-succession shows three interglacial pedocomplexes (V-S1,V-S2 and V-S3) separated by loess layers that include at least one interstadial pedocomplex in the uppermost loess layer. All sediments show a bipartite grain-size distribution (a coarser-grained silt-dominated one and a fine-grained one (<16 μm)). The interglacial palaeosols show a slightly finer-grained mean grain size than the interstadial soils and loess layers, which is entirely determined by the higher proportion of the fine subpopulation. Laterally, the palaeosols vary from a black organic, chernozem-like soil to a brown-coloured inorganic soil. There are no significant differences in grain size between the two soil types. In the vertical succession, the jumps in grain-size do not correspond always with the soil colour. Furthermore, there is no clay illuviation. It may be concluded from this multi-proxy study that the locally higher amount of the fine-grained component seems corresponding with a more humid depositional environment. Another important conclusion is that all loess shows identical grain-size composition and thus that interglacial loess with distinct finer grain-size as is the case in Asian loess (also in the coarser subpopulation) is clearly absent. [Copyright &y& Elsevier]

This paper deals with the review of pollen based palaeoclimatic records available from the South-west monsoon dominated northeast part of India. Here, a complete overview of available Late Pleistocene–Holocene records of the past vegetation vis-à-vis climate is structured based on a latitudinal subdivision of the region. The broad spectrum of the past climate in terms of humid/dry, warm/cold inferred by variations of some key pollen or group of pollen taxa is depicted diagrammatically, thereby providing a glimpse of spatio-temporal vegetation vis-à-vis climatic changes. Here, we attempt to create a standard diagrammatic scale with more reliability than using relative terminology to infer past climate records, based on pollen data from sub-surface sediments. [ABSTRACT FROM AUTHOR]

Abstract: The application of ostracod shell chemistry as a paleoenvironmental tool has grown within the past decades. Most studies have investigated Mg and Sr in ostracod shells as proxies for temperature and salinity, and the use of a wide range of trace elements as prospective paleoenvironmental indicators has yet to be developed for lacustrine systems. Only a few preliminary studies have used trace metals in paleolimnological studies such as Cd, Ba and Zn as paleonutrient indicators, or Mn, Fe and U as redox and oxygenation indicators. This paper reviews the state of the art of geochemical analyses in microfossils such as ostracods, foraminifera, and corals, and provides insights in new trace element proxies with the goal to promote the use of trace elements in ostracod shells as paleoenvironmental proxies. In paleoceanography, foraminifera and corals are most prominently used to reconstruct past climate conditions. Well-established proxies such as δ18O, Mg/Ca and Sr/Ca provide information about changes in sea surface temperatures. In addition, a great number of new proxies have been developed recently, such as radiogenic isotopes and redox sensitive trace elements. In paleolimnology, ostracod shell chemistry is widely used to assess paleohydrological changes. Reconstruction of temperature and salinity changes in lake environments is often achieved by oxygen isotopes as well as Mg/Ca and Sr/Ca ratios, but depending on the hydrological and geological settings of the lake system, local calibrations are needed to assess which proxy is suited to reflect which processes. New proxies need to be tested by novel techniques that recently have become available. Compared to conventional instrumentation used in ostracod shell chemistry, methods such as Laser Ablation ICP-MS and NanoSIMS allow single shell analysis and provide high-resolution data. The potential of ostracods in paleolimnology is not yet fully assessed, but can be developed by learning from paleoceanographic studies. [Copyright &y& Elsevier]

Abstract: The role of climate change on civilization evolution, varying from a driving force, to a supporting role or just background noise, is an often-debated issue. This paper presents the occupation history of prehistoric civilization in the hyperarid Tarim Basin as a case study to evaluate the influences of environmental change. The prehistorical relics in the Tarim Basin are centered at two periods: prior to 3000 BP and after 2700 BP, showing an apparent centurial gap in occupation. The gap is bridged by the relics from the Kunlun highland, 3000–2600 BP. Previous palaeoclimatic reconstructions show an anti-phased moisture changes between the southern Tarim and the Kunlun highland during the past 5000 years. Placing the timing of relics in the climatic context, the prehistoric relics only occur during relatively wet periods, both on the Kunlun highlands and in the southern basin. The pattern indicates that moisture change is an important explanation for relic distributions in southern Tarim. During the succession of relics from both the basin and the highland, cultural complexities increased gradually from 3800 BP to the historical period, without any significant absences or collapses. This implies that ancient cultures can develop, although the people migrated between the highland and the basin. The results show that in this case environmental pressures have little influence on civilization evolution, even in such a fragile habitat and during prehistoric periods. Caution is required in assessing the influences of environmental change on civilizations. [Copyright &y& Elsevier]

Abstract: Paleoclimate and paleoenvironmental studies in the north-eastern Italian Alps have been hampered by the rarity of well-preserved high-altitude deposits and the lack of high-resolution multi-proxy records with adequate chronological control. This paper presents the first complete Late Glacial to Holocene peat succession from the Dolomites (Danta di Cadore, Belluno, Italian Alps). A 7 m core was used to evaluate the potential of the ombrotrophic Val di Ciampo peat deposit (1400 m a.s.l.) as an archive of environmental and climate change. The depth–age scale is based upon independent 14C and 210Pb dates and combined with peat stratigraphy demonstrates that the peat core covers more than 13,200 cal BP, extending to the end of the last part of the Late Glacial. Bulk density, inorganic matter content, pore water pH, conductivity, Ca/Mg ratios, and Ca, Sr and Ti trends were used to identify changes in trophic conditions through the bog. The boundary between ombrotrophic and minerotrophic conditions occurs at approximately 400 cm below the surface and demonstrates that this core is the longest Eastern Alpine ombrotrophic record yet obtained, corresponding to 7000 cal BP. The high-resolution chemical data of this peat archive improves our understanding of European Alpine Holocene climate variability and the relationship between natural climate fluctuations and anthropogenic climate change during the present interglacial in the Dolomites. [Copyright &y& Elsevier]

Abstract: New paleoclimatic data for the Lateglacial clarify climatic phases during the Lateglacial. Cold climate played a key role in limiting Magdalenian expansion from southwest and central Europe This paper presents chronological and geographic data for the different climatic phases to map the expansion of the Magdalenian into northwest Europe. Specifically, it can be seen that initial expansion follows a southwest-northeast trajectory into southern Germany, followed by northern expansion into Belgium, central Germany and the Paris Basin at the end of the Oldest Dryas. During the Bølling and Allerød phases, human occupation intensified in the Paris Basin and contacts and/or territorial exploitation between both the Paris Basin and the Rhineland region with Belgian territory is demonstrated. [Copyright &y& Elsevier]

Abstract: This paper analyzes the spatial organization of two layers corresponding to the first half of the Middle Holocene from the Hornillos 2 rockshelter (Susques, Jujuy Province). Some important issues taken into account are the good preservation of the site and the sedimentary deposition processes which coincide with paleoclimate aspects. Correlation of different archaeological lines of evidence allows interpretation of the connection between several activity areas and their occupational intensity. There is a trash heap related to a short occupation period at the beginning of the Middle Holocene and a main zone of intense activity ca. 6200 yrs BP. These facts are in accordance with the archaeological expectations proposed for certain periods of the Middle Holocene. [Copyright &y& Elsevier]

Abstract: Loess-palaeosol sequences represent important palaeoclimatic and palaeoenvironmental archives on land. Furthermore, loess deposits in the Vojvodina region (North Serbia) can be regarded as one of the most important European terrestrial records of climatic and environmental changes during the last million years which makes them valuable scientific resource. Unfortunately, these sites are endangered by numerous, mostly human, factors and could be degraded permanently. Besides the scientific community, these geosites could be presented and interpreted (geotourism) to a much wider audience. This paper presents an introduction with general overview of the evaluation and conservation methods and sustainable promotion of loess sediments and their possible implications in the Vojvodina region. The proposed methods could also be further applied to other geologically equivalent locations worldwide. [Copyright &y& Elsevier]