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The northern edge of the East Asian monsoon region is also a transition zone of temperate continental and monsoon climate, which is a sensitive zone of global climate and ecological environment change. It is an urgent problem to find out the long-term climate change rules of this region. Using 101 tree core samples obtained from 54 trees, a 343-year tree-ring width chronology of the Platycladus orientalis (L.) Franco (1673–2016) in the Wula Mountains, Inner Mongolia, China was established. The analysis shows that the radial growth of P. orientalis is closely related to hydrothermal conditions, the average minimum temperature and relative humidity are the main factors that determine the growth of P. orientalis. Based on the strong correlation between the tree-ring indices and the annual average minimum temperature (r = −0.870, p < 0.001), we reconstructed an average annual minimum temperature series from 1673 to 2016 using a linear regression equation, and the reconstructed equation can explain 75.724% of the variance, respectively. According to the data from the past 343 years, the changes in the annual average minimum temperature series had the cycles of 58.6-, 7.7-, 3.4-, 3.1-, 2.2-, and 2.1-years; the series showed three warm periods (1824–1830, 1909–1922, and 1986–2011) and 4 cold periods (1703–1712, 1731–1738, 1754–1763, and 1937–1951). The low temperature periods recorded in the reconstructed series for the 17th and 18th centuries are consistent with the Little Ice Age that occurred in the northern hemisphere, and the heating rate significantly increased at the end of the 20th century. In addition, the cold and warm periods recorded by the reconstruction result is basically consistent with the extreme climate events recorded in the historical documents of the region and the reconstruction results in other regions. In this paper, the world's first chronology of P. orientalis tree ring width was established. A historical sequence of annual average minimum temperature of 343 years was reconstructed in a typical region of the East Asian monsoon climate. It fills in the blank of reconstruction sequence and variation characteristics of mean minimum temperature in the northern edge of East Asian monsoon and transition zone of temperate continental and monsoon climate in recent four centuries. [ABSTRACT FROM AUTHOR]

The Yiluo region in the middle Yellow River has been a core area of archaeological inquiry for understanding the origins of the first dynastic states in China. In order to investigate the social changes on a regional scale, a systematic full-coverage regional survey project was carried out from 1997 to 2018, covering an area of 1183 km2 in the Yiluo region. This paper analyzes the settlement patterns of 451 sites of the Neolithic and Bronze Ages (ca. 6000–200 cal. BC), providing the most comprehensive pictures yet, of the spatial and temporal relationships of settlement distribution during a nearly 6000-year time span. The paper demonstrates a developmental trajectory from a landscape dotted with scattered, small Neolithic villages to a highly centralized dynastic heartland in early Chinese civilization. The evolutionary pathways were not straightforward, but were characterized by episodic fluctuations in population density, and the rise and fall of complex societies. Holocene climatic fluctuations may have played significant roles affecting human activities, but it is the human responses to external challenges in various ways that ultimately determined the trajectories of social evolution. [ABSTRACT FROM AUTHOR]

The 4.2 ka event was one of Holocene abrupt-change events and characterized by dry and cool climatic conditions in many parts of the world. The event was reported to have played important roles in the collapses of those major ancient civilizations. This paper first attempts to portray a global picture of this "4.2 ka Event" and then reviews those reliably-dated sequences containing "4.2 ka Event" retrieved from the domains of four major civilizations. This review further confirms the proposition advocated by the International Stratigraphy Committee that 4.2 ka was the chronological divider between the warmer-wetter middle Holocene and the cooler-drier late Holocene. This review also lends a further support to early proposals that the declines or disruptions of Ancient Egyptian Culture, Mesopotamian Culture, and Ancient Indian Culture at ∼4.2 ka BP were directly or indirectly associated with the "4.2 ka Event". In Chinese cultural domain, the derailment of nearly all of the well-developed Neolithic cultures at ∼4.2 ka BP was also chronologically correlated with the proxy data-recorded abrupt climatic change at ∼4.2 ka BP. But, it should be admitted that either drying or cooling or drying and cooling at ∼4.2 ka BP might not be sufficient to collapse these well-developed cultures in presently warm and wet southern China. Surely, further studies are needed for constraining the climatic and environmental variables at ∼4.2 ka BP not only in southern China but also in the adjacent Central Plains of China. [ABSTRACT FROM AUTHOR]

Henan area is climatologically situated in the transition between northern and southern China and the transition is reported to be highly sensitive to climate changes during the Holocene. To better understand the Holocene climatic and environmental changes in Henan area where high-quality data are lacking, this paper first reviewed those published palaeoenvironmental records in attempt to provide a low-resolution framework of the Holocene environmental changes in Henan area, and then synthesized the moisture proxy records from the surrounding areas in attempt to define a high-resolution trend of the Holocene moisture variation for our target site (i.e., Zhengzhou within Henan area). Two major conclusions can be drawn. First, the high-resolution Holocene moisture curve for our target site well follows the general moisture trend of China and the curve is well corroborated by two recently-reported data sets: one from Mangshan loess-palaeosol sequence and another from Laomu-Dongshiya Cave. Second, our synthesis supports an earlier notion stating that the "Holocene Moisture Optimum" in China was a delayed response to the oceanic "Holocene Thermal Optimum". The latter might in turn be a delayed response to the summer insolation peak. [ABSTRACT FROM AUTHOR]

In recent years, archaeologists have studied how ancient humans have shaped, and been shaped by, their surrounding environments in an effort to provide valuable insight into the patterns of human-environment interaction during prehistoric and historical periods. Along the Heihe River in Hexi Corridor of northwest China, archaeologists have found many ancient cities that are good places to explore changes in human settlement patterns in relation to environment change in historical periods. In this paper, we present our investigation of seven ancient cities to clarify the chronology of these cities and their strategy for wood use in the area through the application of radiocarbon dating and charcoal identification. Our results suggest that the ages of many cities are younger than previous estimates, and humans mainly used Tamarix and mixed Tamarix and broad leaf trees in the lower and middle reaches of the Heihe River basin between ∼ AD 240–1380 respectively, and roughly matches the modern spatial distribution of natural woody vegetation in the area. In comparison to the results of archaeological, paleoclimatic and historical studies in Hexi Corridor, we propose that ancient human strategies for wood use and their impact on environment of the Heihe Basin are primarily relevant to human lifestyles rather than climate change. [ABSTRACT FROM AUTHOR]

In northwestern China, many historical nomadic kingdoms and Chinese dynasties sought to control the Heihe River basin, an important location on the eastern part of the ancient Silk Road. Archaeologists have argued that changes in material culture are tied to the frequent turnover in polities in the area, but no published evidence supports these claims. In this paper, we evaluate the relative importance of environmental and political factors in determining the spatiotemporal pattern of archaeological sites in the middle and lower reaches of the Heihe River basin by using previously published high-resolution paleoclimate records and a variety of historical documents. Our results indicate that humans intensively exploited the Heihe River basin during Han dynasty (202BC–AD 220). Following the Han dynasty, during the Wei-Jin (AD 222–589) and Sui-Tang (AD 581–907) periods the number of archaeological sites. In the Western Xia-Yuan period (AD 1038–1368), people mainly settled in the lower reaches of the Heihe River basin and only returned to the middle reaches of the Heihe River basin during the Ming and Qing dynasties (AD 1368–1912). Although climate change and the local environment affected human activities in Heihe River basin, geopolitical events, such as forced mass migrations, are more responsible for influencing the distribution of archaeological sites over the past 2000 years. [ABSTRACT FROM AUTHOR]

As a part of the INQUA project “A Global Digital Database and Atlas of Quaternary Dune Field and Sand Seas”, 337 age records from the desert dunes of China and 20 from Mongolian dune fields have been compiled in the database. This has opened the possibility of exploring and synthesizing the Quaternary environmental changes in the Asian mid-latitudes dune fields directly from the on-site aeolian sand archives. This paper assessed the sand dune chronologies in terms of geographical distribution, data quality and their implications for late Quaternary palaeoenvironmental reconstructions. The available ages are concentrated mainly in the last 20 ka and many are from the fields of stabilized dunes in the eastern portion of the desert belt in northern China. The number of records and the ratio between the records of stable state and the total records could act as a proxy for the palaeoenvironmental interpretation. The aeolian sand activities deciphered from the chronological data in the eastern portion of the desert belt in northern China show a reasonable correlation with the general global climatic curves at the glacial–interglacial timescales. The limited aeolian sand records from the glacial period, however, hamper the understanding of the detailed features (e.g., forms and processes) of the dune fields during glacial times. In the last two millennia, however, there has not been any meaningful correlation between aeolian dune activity and climatic variation at the centennial time scales, probably due to the complexity of the aeolian sand systems and human interventions. Extending the coverage of dune chronology both temporally and spatially is urgently needed for a full understanding of the environmental changes in the dune fields. [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]

Runoff has been in decline in most river basins in China during the last 50 years. The Weihe River, the largest tributary of the Yellow River, has experienced runoff declines as large as 35% in the last century. Little is known regarding the relative contributions of climate and human impact to the observed hydrological trends in the Weihe River Basin. In the present paper, data from seven hydrological stations and 21 meteorological stations are used to analyze the long-term trends of precipitation, temperature, and streamflow. Using the daily climatic data, a Variable Infiltration capacity (VIC) hydrological model is calibrated and verified to a baseline period from 1956 to 1970. Subsequently, natural runoff for the following years (1971–2006) is reconstructed using the VIC model without considering local human impacts. On the basis of observed meteorological data and runoff and the reconstructed runoff data from 1971 to 2006 in the Weihe River Basin, we quantified long-term trends and decadal and annual variations. The results showed that precipitation and runoff have decreased since the baseline decade. We further estimated the relative contributions of human activity and climate change to the hydrological response of the Weihe River Basin and determined that human activity (such as large-scale soil conservation practices and large irrigation areas) has a greater impact on basin runoff than do climate change factors. The percentages in change of runoff due to climate change ( PC ) are 36%, 28%, 53% and 10% in the 1970s, 1980s 1990s and 2000s, respectively. The percentages in change of runoff caused by human activity ( PH ) are 64%, 72%, 47%, and 90%, respectively. [ABSTRACT FROM AUTHOR]

Based on the data of five observed meteorological elements (temperature, precipitation, wind speed, sunshine duration, and relative humidity) from 22 stations, the paper investigated the climate variations in northern Xinjiang over the past 50 years. The analytical results showed that both the temperature and the precipitation have increased significantly (0.35 °C/10 y, 11.2 mm/10 y) during the period of 1960–2011. An abrupt change was detected to have occurred in 1986 for temperature and in 1987 for precipitation. Autumn was the season when the temperature increased most dramatically, and winter and autumn were the seasons when the precipitation increased most dramatically. The twenty years after 1990 were the warmest and wettest two decades of the past ∼50 years, but the warming and wetting paces have slowed down during the same period. The results also showed that the mean annual minimum temperature increased more dramatically than the mean annual maximum temperature, resulting in a greatly reduced diurnal range. The reasons or mechanisms for rising trend of temperature during the past 50 years and also for the faster rising rate of the temperature in northern Xinjiang and the adjacent areas have been reasonably explored in published literature. However, the reasons or mechanisms for the rising trend of the past 50-year precipitation in northern Xinjiang and the adjacent areas have not been reasonably explored. This wetting trend has not extended further to the surrounding areas including Republic of Mongolia, major part of North China, and five republics of the former Soviet Union, and the need is thus pressing to explore the reasons or mechanisms behind this relatively “localized” wetting trend. [ABSTRACT FROM AUTHOR]

Abstract: With increasing collaboration between archeology and natural sciences, research on past human–environment interactions has received more attention in recent years. This paper uses nineteen radiocarbon and OSL dates from three profiles to explore environmental evolution of the Liyang Plain, investigate the spatial and temporal distributions of archaeological sites from the Paleolithic Age to the Shang–Zhou period and discuss relationships between human cultures and environmental changes. The results show that Paleolithic sites are mainly distributed in surrounding mountainous and hilly areas, changing to the plain in the late Paleolithic Age. Climatic cooling during the Last Glacial Maximum did not cause severe damage to the regional vegetation and ecosystem, which allowed the continuous development of the late Paleolithic culture in the Liyang Plain. Suitable environmental conditions and progression of human activities facilitated rice cultivation in the early Holocene, and rice agriculture as an important food resource provided a solid material foundation for social development. The number of archaeological sites increased continuously and their distribution expanded considerably into eastern low-lying plain areas during the Neolithic Age. These trends reversed in the late Shijiahe culture, and social development did not recover until the Shang–Zhou period. Variation of site distribution in the Liyang Plain was primarily influenced by hydrological and geomorphological changes as well as climate change. However, it might also have been affected by broader regional political situations, especially during the Shang–Zhou period. [Copyright &y& Elsevier]

Abstract: The Majiayao culture (5300–4000 cal BP) is the most important culture of the Neolithic period in Gansu and Qinghai Provinces, northwest China, but its development and external connections remain unclear. This paper examines changing spatial and temporal patterns of the Majiayao culture and its subsistence strategies in relation to climate change. The research employed GIS analysis of data from the national archaeological survey, review excavation reports of Majiayao sites, and high-resolution paleoclimate records in northwest China. The results indicate that during the three phases of the Majiayao period (Majiayao, Banshan and Machang) site distribution, site density, and subsistence strategies exhibited significant shifts. This variability seems mostly due to changing precipitation that affected agricultural production and hunting resources. [Copyright &y& Elsevier]

Abstract: This paper describes the palynological, sedimentological and geochemical results obtained from a 6 m core taken from Lake Dajiuhu in Shennongjia Mountains, central China, spanning the last 40,000 BP. The site is located in a subtropical area which is known for harboring many endemic species. The pollen record shows that past climate changes during the Glacial allowed the persistence of warm trees and even subtropical taxa. The percentages of arboreal pollen taxa vary from 40% before and during the last glacial period to ∼60% during the Holocene. The δ13C data indicate that the dominant vegetation was composed of C3 plants. However, despite the continuous presence of tree taxa around the site, the total organic carbon indicates that the biomass was very low during the glacial period (MIS 3 and 2), related to the dominance of conifers and evergreen tree taxa, which are very low biomass producers. The total organic carbon (TOC) started to increase steadily at the end of the last glacial period (end of MIS 2), which reflects the sharp increase in the amount of Sphagnum spores recorded at the end of MIS 2, marking the beginning of the peat bog formation and the increase of the in-situ biomass. The summergreen taxa, which increased during the Holocene, may have also contributed to the TOC increase. [Copyright &y& Elsevier]

Abstract: As in many other regions of the world, the Late Pleistocene in China underwent rhythmic changes of climate, which caused some obvious changes in mammalian fauna, natural landscape and human cultural adaptations. This paper is a brief introduction of four representative Late Pleistocene sites in North China, which are dated at periods between Middle and Upper Palaeolithic, and demonstrated common or particular features from geographic and geological aspects, archaeological and environmental characters, and chronological position. A large transformation happened, reflected by culture remains, showing that environmental changes profoundly influenced human behaviour and inspired new forms of culture appearance. This indicates the clear existence of Middle Palaeolithic at least in North China, which became a foreshadowing for the coming Upper Palaeolithic. [Copyright &y& Elsevier]

Abstract: The present paper reports the recently discovered fossil teeth of Early Pleistocene Gigantopithecus blacki and associated mammalian fauna from Baeryan Cave, Bijie County in Guizhou Province, and also reviews briefly the known fossil sites of Gigantopithecus in south China of Pleistocene. In Early Pleistocene, Gigantopithecus had a wider distribution, but withdrew southward in Middle Pleistocene to a limited area mainly in South China, and it disappeared in the Late Pleistocene according to the present fossil records. Diet and habitat analysis from carbon isotope evidence is used to investigate the reasons for the extinction of Gigantopithecus, which fed on a pure C3 diet and lived in a forest habitat. It was clearly different from early hominins in South and East Africa, such as Australopithecus africanus, Paranthropus robustus and Paranthropus boisei, which had C4 diets. The extinction of Gigantopithecus was also related to the great changes of climate and environment of the Pleistocene, especially the last one million years, during which Homo became more and more prosperous and exerted great pressure on G. blacki. [Copyright &y& Elsevier]

Abstract: High-resolution tree-ring records covering the last hundreds years in north China are very scarce, yet essential for understanding the process and pattern of climate change and designing climate model. In this paper, a Chinese pine (Pinus tabulaformis Carr.) ring-width chronology spanning 1767–2008 AD was developed using standard dendroclimatological methods in the Heng Mountains, Shanxi province of north China. Strongly negative relationships were detected between the ring-width chronology and the monthly mean temperatures (minimum, mean, and maximum) from April to September during the growing season. Based on correlation analysis, the mean temperature from May to June was reconstructed back to 1767 AD. Both spatial correlation analysis with CRU grid dataset and comparisons with other tree-ring based temperature reconstructions from surrounding areas revealed that this reconstruction represented a larger-scale regional temperature variation for north-central China. Significant spectral peaks were found at 2.04-, 2.05-, 2.22-, 7.69-, 75- and 100-year, implying the possible influence of ENSO and solar activity on the local climate. Considering the strong and negative relationship between tree growth and temperature, the future warming will possibly bring increasing drought stress for the tree growth, as shown by the recent warming since the 1950s. However, due to the limit of tree age, this reconstruction did not capture the multi-century scale variations which presents the necessity for developing more and longer tree-ring chronologies in the future in north-central China. [Copyright &y& Elsevier]

As typical inland river basins in China, the Ürümqi River Basin and the Aksu River Basin were selected as study areas in this paper. In the past several decades, the climate has had a tendency to change from warm-drying to warm-wetting, with a coinstantaneous response by mountain glacier meltwater of these areas. Comparing questionnaire survey data with scientific observation, this study focused on the character of public perception on climate and cryosphere changes, the changes' possible impacts on water resources, and adaptation measure choices by the public. Results presented in this study showed that: 1) Perceptions of most respondents on climate and cryosphere changes conform to objective facts, but some of them still have suspicion relating to these environmental changes; 2) Even though increasing precipitation and glacier meltwater has caused an increased water supply, due to the increasing demand of the unit area water for agriculture (industrial and living water demand may be involved), water shortage is still a big problem in sustainable development. Because of unemployment or the inconspicuous benefits of water-saving measures, the wasting of water resources may be a serious problem in these areas; 3) Most people preferred to choose the adaptation measures implemented by government and policy-making departments. Some people showed more preference for measures avoiding unfavorable natural environmental consequences. Public perceptions on the urgency of individual participation are still inadequate. Some of the measures should be communicated broadly and warmly encouraged; 4) Public choices of adaptation measures for climate and cryosphere change are impacted by demographic factors such as age, gender, region, nationality, education and occupation. The impacts of such factors are complicated. [ABSTRACT FROM AUTHOR]

Abstract: Large quantities of archeology and literature records indicate that during the Shang Dynasty and a part of the Zhou Dynasty of Chinese history, about 2000 BC to 1000 BC, there once were wild elephants living in North China. For a long time, it was believed that all of these elephants belonged to the species Elephas maximus. Many scholars suggested that this phenomenon could show a much higher temperature at that time. However, as the research of Chinese historical climate has already indicated, even in the Megathermal Maximum, most of the parts of North China were still controlled by the climate of the Warm Temperate Zone, not the Subtropic Zone. This paper presents evidence suggesting that the so-called “wild elephants” in North China during that time belonged to Palaeoloxodon sp., not E. maximus. [Copyright &y& Elsevier]

Abstract: There is almost no detailed Holocene pollen data in Shandong Province. This paper reports a pollen record from a natural profile at Qingdao of Shandong Province, East China between 7250 and 3500 cal. BP, and provides new evidence for the collapse of Neolithic cultures around Central China in the middle Holocene. It reveals a subtropical deciduous and evergreen broad-leaved forest was well-developed during 7250–5900 cal. BP, representing the Holocene Maximum warm climate condition. During 5900–4550 cal. BP, pollen flora retained the main features of the former stage, but the contents for the major tree components in the flora decreased, implying an end of the Holocene Maximum warmth. From 4550 cal. BP to 3900 cal. BP, the percentage of AP (Arboreal Pollen) abruptly fell to the lowest value in the profile, inferring a distinct climate deterioration. During 3900–3500 cal. BP, a major recovery of AP is captured, indicating a possible climate change. The above mentioned climate changes are in good coherence with the local Neolithic Culture evolution. It is assumed that the cold climate during 4550–3900 cal. BP is possibly responsible for the collapse of the Longshan Culture in Shandong Province. [Copyright &y& Elsevier]

Abstract: Although sand seas are located in arid regions, given that the proportions of dune areas vary greatly from region to region they are clearly influenced by other factors as well as aridity. This paper discusses the distribution pattern and major features of sand seas and large fields of stabilized dunes in northern China, and demonstrates the main influences on their development. It appears that the availability of onsite loose sediments, not wind strength, is critical to the occurrence of the sand seas on a regional scale. Tectonic, endorheic basins or areas of alluvial fans or forelands of mountain ranges are advantageous to the accumulation of fluvial sediments, and thus are ideal locations of large sand seas in an arid climate. The large dune fields currently stabilized by vegetation were active sand seas during the drier periods of the late Pleistocene and early Holocene. The distribution patterns of Chinese sand seas suggest that the height or size of the dunes in the sand seas are determined more by the availability of sands than any other potential factors. As the sand seas in China account for a large portion of deserts in the middle latitudes of the Northern Hemisphere (Taklamakan is the second largest sand sea on Earth), knowledge of these sand seas’ past changes is important for understanding climatic changes in the terrestrial regions of mid-latitudes. [Copyright &y& Elsevier]

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: This paper reports the latest details from two comprehensive investigations of alluvial terrace sequences in Zhangjiajie, northwest Hunan Province, China. Seven alluvial terrace units along the Maoxi River and four terrace sequences along the Suoxi River record significant regional geomorphic history. Rates of regional Quaternary uplift and climate change are reconstructed using topographic and stratigraphic evidence from terrace and adjacent cave deposits, along with Electron Spin Resonance (ESR) and Thermo-luminescence (TL) dating controls. Between 928ka and 689ka the time-averaged uplift rate (or incision rate) was 0.16m/ka. The rate decreased to 0.05m/ka between 689ka and 347ka, and then increased slightly to 0.11–0.14m/ka after 347ka. The inferred incision rate increased roughly from 0.21–0.32m/ka to 0.51m/ka from the Late Pleistocene to present. The seven alluvial phases (T7 −T1) and their associated chronology are consistent with climatic variations at regional and/or global scales, suggesting that these terraces represent climate-driven pauses imprinted atop the record of long-term tectonically induced incision by rivers. Insights from these alluvial terrace staircases and cave features indicate that the spectacular sandstone peak forest landscape of the study area has emerged since the middle period of the Middle Pleistocene. [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: Long monthly streamflow series of three control hydrological stations of the Pearl River basin were analyzed by using the scanning t-test and the scanning F-test. Possible implications of the changing properties of streamflow variations for the water resource management of the Pearl River Delta are also discussed. The results indicated that: 1) more complicated changes were observed in terms of the second center moment when compared to the first original moment. More significant abrupt changes of the second center moment imply more sensitive response of streamflow stability to climate changes and human activities; 2) abrupt behaviors of the first (second) center moment of the streamflow variations tend to be more sensitive to climate changes and/or human activities in the larger river basin when compared to those in the smaller river basin. These phenomena are attributed to buffering functions of more storage space of longer river channel, and more complicated and longer runoff yield and concentration processes in the river basin of larger drainage area; 3) annual minimum streamflow of the Pearl River basin tends to be increasing. This will be helpful for better human mitigation of the salinity intrusion in dry seasons across the Pearl River Delta. Annual maximum streamflow, when compared to annual minimum streamflow, shows larger-magnitude variability reflected by larger standard deviation, implying unfavorable conditions for flood mitigation in the Pearl River Delta. The results of this paper are of scientific and practical merits for water resource management and sound human mitigation to water hazards across the Pearl River Delta, and also are a good case study for similar researches in other river deltas in the world under the changing environment. [ABSTRACT FROM AUTHOR]

Abstract: Water level and chemistry of Lake Qinghai are sensitive to climate changes and are important for paleoclimatic implications. An accurate understanding of hydrological and chemical budgets is crucial for quantifying geochemical proxies and carbon cycle. Published results of water budget are firstly reviewed in this paper. Chemical budget and residence time of major dissolved constituents in the lake are estimated using reliable water budget and newly obtained data for seasonal water chemistry. The results indicate that carbonate weathering is the most important riverine process, resulting in dominance of Ca2+ and DIC for river waters and groundwater. Groundwater contribution to major dissolved constituents is relatively small (4.2 ± 0.5%). Wet atmospheric deposition contributes annually 7.4–44.0% soluble flux to the lake, resulting from eolian dust throughout the seasons. Estimates of chemical budget further suggest that (1) the Buha-type water dominates the chemical components of the lake water, (2) Na+, Cl−, Mg2+, and K+ in lake water are enriched owing to their conservative behaviors, and (3) precipitation of authigenic carbonates (low-Mg calcite, aragonite, and dolomite) transits quickly dissolved Ca2+ into the bottom sediments of the lake, resulting in very low Ca2+ in the lake water. Therefore, authigenic carbonates in the sediments hold potential information on the relative contribution of different solute inputs to the lake and the lake chemistry in the past. [Copyright &y& Elsevier]