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The earliest pottery in East Asia, as is found in several cave sites in southern China, emerges in Upper Paleolithic contexts dating from the Last Glacial Maximum, ∼20 Ka cal BP. The making of simple pottery vessels in Late Pleistocene East Asia also has been noted in eastern Siberia and Japan but not yet in the Central Plains of China. This paper summarizes the better-reported evidence for early pottery sites across the vast region of China south of the Yangtze River, providing details on two dating projects conducted in the cave sites of Xianrendong (Jiangxi Province) and Yuchanyan (Hunan Province). The excavated contexts in these two caves and a few others clearly indicate that this early pottery was the creation of hunter-gatherers who hunted available game and foraged a variety of plant foods. The nature of the cave occupations is ephemeral, and where the published animal and plant remains allow, we suggest that there were repeated, seasonal occupations. In sum, there is no basis yet to suggest that the making of early pottery in South China marked sedentary or plant-cultivating communities. [ABSTRACT FROM AUTHOR]

Abstract: Changes on water resources volume of 1960–2007 in the Upper Reaches of the Yangtze River are discussed in this paper. A time series (1960–2007) and its spatial patterns of actual evapotranspiration (ETa) estimation are analyzed based on Advection-Aridity model (A–A model) with selected parameters for 72 meteorological stations in the upper reaches of the Yangtze River Basin. The result indicates that average ETa of the basin changed in stages: slight increases in the first decade; a drop followed by fluctuations and lower increases in the next ten years; and then a dramatic decline in the latest decade, with three abrupt change years detected in the early 1970s, 1990s, and 2000s. ETa increases from mountainous northwest areas to plains in eastern areas, with significant decreases in plain regions and increases in the mountain region. ETa in the Sichuan Basin is found to decrease at the most rapid rate, and ETa in the sub-area to the south of the upland mountain region is increasing significantly. Such patterns of spatial trend in ETa result in reductions in regional variation, both annually and in all seasons. The change in ETa of this area is believed to be related to local water resource changes, and is impacted by the changes in climate factors. Temperature of this area has increased, and sunshine duration hours have shortened, leading to a reduction in net radiation. Relative humidity also has decreased. Comprehensively, reduction in both energy and moisture supply for evapotranspiration result in an increasing ETa. Moreover, a sharp drop of ETa occurred in the early 2000s, and meteorological factors including wind speed also show abrupt change to different extents. The impact of ETa on regional water balance at both inter-annual and intra-annual scales is also discussed in this study. [Copyright &y& Elsevier]

Abstract: With the increasing accumulation of data on early rice farming in the middle and lower reaches of the Yangtze River, this region has become one of the most important places to trace the origin and development of agriculture. This paper gives a general evaluation of some early rice sites, including the Hemudu, Majiabang, Kuahuqiao, and Shangshan cultures in the lower reaches of the Yangtze River; the Pengtoushan and Chengbeixi cultures, and the Xianrendong, Diaotonghuan and Yuchanyan sites in the middle reaches of the Yangtze River; and the Jiahu site in North China, and recognizes three main development stages of the prehistoric rice forming in China, i.e. initial stage (before 8000 BC, approximately equal to Mesolithic Age), developing stage (between 8000 BC and 5000 BC) and maturating stage (since 5000 BC). The initiation of agriculture is suggested to come with the establishment of more or less sedentary residences, which coexists with the occurrence of pottery making. Warming climate after the last glaciations is considered as a major factor that allowed the distribution of the wild rice northward. Food requirement and storage are another factor in initiating early rice farming, while the increasing population and the Holocene Maximum warm climate condition might greatly promote its development. Evidence from the middle and lower Yangtze River area exhibits the transitional process from a hunting and gathering society to an agriculture-oriented society. [ABSTRACT FROM AUTHOR]

Abstract: Floods often are accompanied by intensified soil erosion and thus high sediment supply from the catchment into the main channel of the river. This paper examined the sediment processes, especially deposition and erosion, during the two extreme flood years in 1954 and 1998, in the middle and low reaches of the Yangtze River. The total amount of sediment supplied to the middle and lower reaches from Yichang–Hankou and Hankou–Datong, was 1095 Mt in 1954 and 855.9 Mt in 1998, or 176% and 137% of the averaged 622 Mt/a from 1950 to 2006. A high deposition occurred in the floodplains, lakes and channels along the section Yichang–Hankou, both in 1954 and 1998. The total deposition reached 635 Mt and 499 Mt in 1954 and 1998 or 138% and 124% of the sediment load measured at the Datong station, respectively. However, different processes in the downstream section Hankou–Datong during the two flood events were found. Severe erosion (−140 Mt) happened in 1954, but only a slight erosion occurred (−22 Mt) in 1998. Thus, the floodplains and channels in the middle and lower reaches of the Yangtze River play an important role in regulating sediment discharge during extreme flood events. The heavy deposition in the middle reaches effectively reduced the amount of sediment discharged into the river mouth and thus acted as a major depocenter in the extreme flood year. The results also suggested that the Yichang–Hankou tended to shift from a depositional section to an erosional section, whereas the Hankou–Datong changed from an erosion-dominated section to a deposition-dominated section even before the Three Gorges Reservoir infilling in 2003. It is anticipated that this tendency would be accelerated and the historical role of sediment regulation by the two reaches could eventually be changed due to the reduced sediment supply from the Upper Yangtze. [ABSTRACT FROM AUTHOR]