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Before completion of the Three Gorges Reservoir (TGR), China, there was growing apprehension that it would become a major emitter of greenhouse gases (GHG): Carbon Dioxide (CO2), Methane (CH4) and Nitrous Oxide (N2O). We report monthly measurements for one year of the fluxes of these gases at multiple sites within the TGR, Yangtze River, China, and from several major tributaries, and immediately downstream of the dam. The tributary areas have lower CO2 fluxes than the main storage; CH4 fluxes to the atmosphere after passage through the turbines are negligible. Overall, TGR showed significantly lower CH4 emission rates than most new reservoirs in temperate and tropical regions. We attribute this to the well-oxygenated deep water and high water velocities which produce oxic mainstem conditions inimical to CH4 emission. TGR's CO2 fluxes were lower than most tropical reservoirs and higher than most temperate systems. This is due to the high load of metabolizable soil carbon delivered through erosion to the Yangtze River. Compared to fossil fuelled power plants of equivalent power output TGR is a very small GHG emitter, annual CO2-equivalent emissions are approximately 1.7% of a coal-fired generating plant of comparable power output. [ABSTRACT FROM AUTHOR]

Two sediment cores from the Changjiang (Yangtze) River estuary and its adjacent East China Sea were collected and studied for eutrophication history using paleoecological records of environmental changes over the last century. A multiproxy approach by using biological and geochemical analyses revealed changes in diatom assemblages, total organic carbon (TOC), total nitrogen (TN) and biogenic silica (BSi) and give an indication of nutrient in status and trends in Changjiang River estuary and its adjacent East China Sea. The diatom assemblages in the two cores generally increased gradually from the 1970s, and accelerated from the 1990s until now, reflecting the increased eutrophication and causing large algae blooms/red tides. The TOC, TN and BSi showing the similar trends, supported the interpretation of the eutrophication process indicated by diatom analyses. The two cores were located in different sea areas of the East China Sea, and we discuss their relative changes based on their environment characteristics. We also discuss the potential effect of anthropogenic influences and ongoing projects on eutrophication in the Changjiang River and its adjacent East China Sea. [ABSTRACT FROM AUTHOR]

Model studies suggested that human-induced increase in nutrient load may have stimulated primary production and thus has enhanced the CO2 uptake capacity in the coastal ocean. In this study, we investigated the seasonal variations of the surface water's partial pressure of CO2 (pCO2sw) in the highly human-impacted Changjiang-East China Sea system between 2008 and 2011. The seasonality of pCO2sw has large spatial variations, with the largest extreme of 170±75 µatm on the inner shelf near the Changjiang Estuary (from 271±55 µatm in summer to 441±51 µatm in autumn) and the weakest extreme of 53±20 µatm on the outer shelf (from 328±9 µatm in winter to 381±18 µatm in summer). During the summer period, stronger stratification and bio-logical production driven by the eutrophic Changjiang plume results in a very low CO2 in surface waters and a very high CO2 in bottom waters on the inner shelf, with the latter returning high CO2 to the surface water during the mixed period. Interestingly, a comparison with historical data shows that the average pCO2sw on the inner shelf near the Changjiang Estuary has decreased notably during summer, but it has increased during autumn and winter from the 1990s to the 2000s. We suggest that this decadal change is associated with recently increased eutrophication. This would increase both the photosynthetic removal of CO2 in surface waters and the respiratory release of CO2 in bottom waters during summertime, thereby returning more CO2 to the surface during the subsequent mixing seasons and/or episodic extreme weather events (e.g. typhoons). Our finding demonstrates that increasing anthropogenic nutrient delivery from a large river may enhance the sequestration capacity of CO2 in summer but may reduce it in autumn and winter. Consequently, the coastal ocean may not necessarily take up more atmospheric CO2 in response to increasing eutrophication, and the net effect largely depends on the relative time scale of air-sea gas exchange and offshore transport of the shelf water. Finally, the case we reported for the Changjiang system may have general ramifications for other eutrophic coastal oceans. [ABSTRACT FROM AUTHOR]

Green port construction has a profound impact on China's international climate commitment to carbon neutrality by 2050. To examine the carbon emission reduction potential of 20 major ports in the Yangtze River Delta port cluster of China, this study takes the perspective of environmental efficiency and employs dynamic exogenous variable DEA in efficiency evaluation. The results show the increasing environmental efficiency of the ports in the Yangtze River Delta, rising from 0.5116 in 2013 to 0.7276 in 2019. Also, there are significant spatial differences in efficiency. After considering exogenous variable, the average efficiency has increased from 0.5537 to 0.6276, indicating that regional green development is a critical factor in port environmental efficiency evaluation. Finally, the overall efficiency of input and output have risen, the slackness of carbon emission shows a trend of decreasing, and there is great potential for reducing carbon emissions from the perspective of port environmental efficiency. The previous studies paid less attention to dynamic efficiency, exogenous variables, and carbon emission. Therefore, this paper is the first comprehensive examination on the carbon emission reduction potential of China's Yangtze River Delta port cluster from the perspective of dynamic environmental efficiency. [ABSTRACT FROM AUTHOR]

Rivers have been under sampled to establish them as sinks or sources of the atmospheric carbon oxide (CO2). Such poor coverage is well known for tropical and sub-tropical, particularly monsoon driven rivers. An unprecedented high-temporal-resolution (daily) sampling during July 2008-August 2009 were conducted from the Longchuanjiang River of the upper Yangtze basin, a subtropical monsoon river in China to reveal the daily-to-seasonal dynamics of the partial pressure of CO2 (pCO2) and CO2 degassing flux from the river. The pCO2 levels were supersaturated in CO2 with respect to atmospheric equilibrium (380 µatm) during the entire survey period with obvious daily and seasonal variations, ranging from 450 to 63000 µatm with an average of 3900 µatm. pCO2 values in the surface water in the wet season were relatively low, except flooding period in November, due to a dilution effect by heavy rainfall. However, both daily and monthly minimal and maximal pCO2 also occurred in this period. In contrast, the pCO2 levels in the dry season were much higher, mainly resulted from lower pH by anthropogenic activities. Net CO2 flux and pCO2 were strongly correlated with pH, but weakly with water temperature, dissolved inorganic carbon and water discharge, and uncorrelated with particulate nutrients and biogenic elements. The estimated water-to-air CO2 degassing flux in the Longchuanjiang River was about 110 mol m-2 yr-1, with the upper limit of 460 mol m-2 yr-1. Our study also indicated that among the total organic carbon remobilized through soil erosion, around 17% (11 400tC yr-1) of was emitted to the atmosphere, 52% (35 000tC yr-1) deposited in the river-reservoirs system and 31 % (21 000tC yr-1) exported further downstream. High spatial and temporal resolution of estimates of CO2 emission from the world large rivers is required due to that catchment characteristics and anthropogenic activities are extremely heterogeneous in space and time. [ABSTRACT FROM AUTHOR]

Dissolved nitrous oxide (N2O) was measured in the waters of the Changjiang (Yangtze River) Estuary and its adjacent marine area during five surveys covering the period of 2002-2006. Dissolved N2O concentrations ranged from 6.04 to 21.3 nM, and indicate seasonal variations with high values occurring in summer and spring. Dissolved riverine N2O was observed monthly at station Xuliujing of the Changjiang, and ranged from 12.4 to 33.3nM with an average of 20.8±7.8 nM. The average annual input of N2O from the Changjiang to the estuary and its adjacent area was estimated to be 15.8×106 mol/yr. N2O emission rates from the sediments of the Changjiang Estuary in spring ranged from -1.88 to 2.02 μmolm-2 d-1, which suggest that sediment can act as either a source or a sink of N2O in the Changjiang Estuary. The annual sea to air N2O fluxes from the Changjiang Estuary were estimated to be 6.8±3.7, 13.3±7.2 and 14.9±8.3 μmolm-2 d-1 using LM86, W92 and RC01 relationships, respectively. The annual sea to air N2O fluxes from the adjacent marine area were estimated to be 8.5±7.8, 15.3±13.5 and 17.4±15.7 μmolm-2 d-1 using LM86, W92 and RC01 relationship, respectively. Hence the Changjiang Estuary and its adjacent marine area is a net source of atmospheric N2O. [ABSTRACT FROM AUTHOR]

Investigating the characteristics of urban expansion is helpful in managing the relationship between urbanization and the ecological and environmental issues related to sustainable development. The Defense Meteorological Satellite Program/Operational Line-scan System (DMSP/OLS) collects visible and near-infrared light fromthe Earth's surface at nightwithoutmoonlight. It generates effective time series data for mapping the dynamics of urban expansion. As a major urban agglomeration in the world, the Yangtze River Delta Urban Agglomeration (YRDUA) is an important intersection zone of both the "Belt and Road Initiative" and the "Yangtze River Economic Belt" in China. Therefore, this paper analyses urban expansion characteristics of the YRDUA for 1993-2012 from urban extents extracted from the DMSP/OLS for 1993, 1997, 2002, 2007, and 2012. First, calibration procedures are applied to DMSP/OLS data, including intercalibration, intra-annual composition, and inter-annual series correction procedures. Spatial extents are then extracted from the corrected DMSP/OLS data, and a threshold is determined via the spatial comparison method. Finally, three models are used to explore urban expansion characteristics of the YRDUA from expansion rates, expansion spatial patterns, and expansion evaluations. The results show that the urban expansion of the YRDUA occurred at an increasing rate from 1993-2007 and then declined after 2007 with the onset of the global financial crisis. The Suxichang and Ningbo metropolitan circles were seriously affected by the financial crisis, while the Hefei metropolitan circle was not. The urban expansion of the YRDUA moved from the northeast to the southwest over the 20-year period. Urban expansion involved internal infilling over the first 15 years and then evolved into external sprawl and suburbanization after 2007. [ABSTRACT FROM AUTHOR]

In this paper, we explored the trends of the atmospheric moisture budget, precipitation, and streamflow in summer during 1961 to 2005 and possible correlations between them by using the linear regression method in the Yangtze River basin, China. The results indicate that: (1) increasing tendencies can be detected in the atmospheric moisture budget, precipitation and streamflow in the Yangtze River basin; however, the significant increasing trends occur only in the atmospheric moisture budget and precipitation in the middle and lower Yangtze River basin; (2) both the ratio of summer moisture budget to annual moisture budget and the ratio of summer precipitation to annual precipitation exhibit a significant increasing trend in the Yangtze River basin. The ratio of summer streamflow to annual streamflow is in a significant increasing trend in Hankou station. Significant increasing summer precipitation can be taken as the major controlling factor responsible for the higher probability of flood hazard occurrences in the Yangtze River basin. The consecutively increasing summer precipitation is largely due to the consistently increasing moisture budget; (3) the zonal geopotential height anomaly between 1991 and 2005 and 1961 and 1990 is higher from the south to the north, which to a large degree, limits the northward propagation of the summer monsoon to north China. As a result, the summer moisture budget increases in the middle and lower Yangtze River basin, which leads to more summer precipitation. This paper sheds light on the changing properties of precipitation and streamflow and possible underlying causes, which will be greatly helpful for better understanding of the changes of precipitation and streamflow in the Yangtze River basin. [ABSTRACT FROM AUTHOR]

This review paper provides a brief review on the development of ideas in the fields of the sea level change of the ECS (East China Sea), the history of the Yangtze River entering the sea and paleochannels in the shelf of the ECS since the Last Glacial Maximum (LGM). The paper summarizes two opposite theories about the Yangtze River entering the sea during the LGM. One theory is that the Yangtze River input a lacustrine in the north of Jiangsu province which was defunct in middle Holocene, and the river was once dry. The other was that the Yangtze River still existed and entered into the Okinawa Trough during the LGM, but scholars share different opinions on which course the river ran across and which place the river input the trough. This paper concludes future work is to study the evolution of the Yangtze River and the paleoclimate and the corresponding events as a whole from the view of regional and even global change, and more attention should be paid to the study on mud sediment, the Yangtze River's response to the changes in climate and sea-level, and the channel metamorphosis. [ABSTRACT FROM AUTHOR]

In the late 1990s, China’s Yangtze and Yellow River Basins suffered devastating natural disasters widely attributed to the degradation of soil and water resources. The Government of China responded with a number of major environmental programs, the most expensive and influential of which, the Grain for Green (GfG) Program, was implemented widely from 1999. Under the GfG Program—also known as the Sloping Land Conversion or Conversion of Cropland to Forest Program—the central government compensates farmers to convert cropland on steep slopes or otherwise ecologically sensitive areas to forest or grassland. Its long-term success depends on households’ ability to make sustainable changes to their household income streams and income diversification strategies. In this paper, we use a difference-in-difference estimation approach to examine the role of migration as a household-level response to the GfG Program, testing the extent to which individuals migrate following a reduction in land available for farming. Importantly, we exploit 15 years of data on migration decisions and establish that participating and non-participating households were on parallel migration paths before the program, thus refuting a key threat to causality in a difference-in-difference model. We find that participating families do, in fact, choose migration as an income diversification strategy more frequently than non-participants. The program effects varied over time but peaked post-Great Recession in 2011 when migration rates in GfG households exceeded those of non-GfG households by 5.9% points (p = 0.003) or about 26%. Our findings should encourage policymakers that families are making long-term adjustments to their livelihood strategies to avoid poverty in anticipation of the eventual withdrawal of government supports. [ABSTRACT FROM AUTHOR]

This paper investigates the long-run development of China's treaty ports from the mid-eighteenth century until today. Focusing on a sample of prefectures on the coast or on the Yangtze River, I document the dynamic development paths of treaty ports and their neighbors in alternate phases of closedness and openness. I also provide suggestive evidence on migration and sector-wise growth to understand the advantage of treaty ports in the long run. [ABSTRACT FROM AUTHOR]

A better understanding of the runoff variations contributes to a better utilization of water resources and water conservancy planning. In this paper, we analyzed the runoff changes in the Yangtze River Basin (YRB) including the spatiotemporal characteristics of intra-annual variation, the trend, the mutation point, and the period of annual runoff using various statistical methods. We also investigated how changes in the precipitation and temperature could impact on runoff. We found that the intra-annual runoff shows a decreasing trend from 1954 to 2008 and from upper stream to lower stream. On the annual runoff sequence, the upstream runoff has a high consistency and shows an increasing diversity from upper stream to lower stream. The mutation points of the annual runoff in the YRB are years 1961 and 2004. Annual runoff presents multitime scales for dry and abundance changes. Hurst values show that the runoffs at the main control stations all have Hurst phenomenon (the persistence of annual runoff). The sensitivity analyses of runoff variation to precipitation and temperature were also conducted. Our results show that the response of runoff to precipitation is more sensitive than that to temperature. The response of runoff to temperature is only one-third of the response to precipitation. A decrease in temperature may offset the impact of decreasing rainfall on runoff, while an increase in both rainfall and temperature leads to strongest runoff variations in the YRB. [ABSTRACT FROM AUTHOR]

During the past few decades, the ecosystems of lakes have been reshaped greatly by global climate change and expanding human activities. As the second largest freshwater lake in China, Dongting Lake is the most important regulating lake in the Yangtze River Basin because it has extensive flood storage capacity. The dynamic characteristics of its circulation and sediment transport are significantly affected by the scheduling and interception of control reservoirs at the upper reaches of the Yangtze River. In this paper, a central lake reservoir is proposed to improve the flood and drought resistance of Dongting Lake. The efficiency of the central lake reservoir is investigated numerically by developing a two-dimensional shallow water model. We demonstrate that current velocity and water elevation during flood and drought events can be influenced significantly by the construction of the central lake reservoir. The flood storage capacity of the central lake reservoir can reduce the peak flood elevation significantly in West Dongting Lake, which would enhance its flood resistance. The water replenishment of the central lake reservoir in the dry season can also efficiently increase the lake water elevation to enhance the drought resistance in the area surrounding the lake. Our findings have important implications for policy makers and their management of Dongting Lake. [ABSTRACT FROM AUTHOR]

Middle and eastern routes of the South-North Water Diversion Project (SNWDP) of China, which are approximately located within the area 28°-42°N and 110°-122°E, are being constructed. This paper investigates the past climatic variations on various time scales using instrumental and proxy data. It is found that annual mean surface air temperature has increased significantly during the past 50-100 years, and winter and spring temperatures in the northern part of the region have undergone the most significant changes. A much more significant increase occurs for annual mean minimum temperature and extreme low temperature than for annual mean maximum temperature and extreme high temperature. No significant trend in annual precipitation is found for the region as a whole for the last 50 and 100 years, although obvious decadal and spatial variation is detectable. A seesaw pattern of annual and summer precipitation variability between the north and the south of the region is evident. Over the last 100 years, the Haihe River basin has witnessed a significant negative trend of annual precipitation, but no similar trend is detected for the Yangtze and Huaihe River basins. Pan evaporation has significantly decreased since the mid-1960s in the region in spite of the fact that the trend appears to have ended in the early 1990s. The negative trend of pan evaporation is very significant in the plain area between the Yangtze and Yellow Rivers. There was a notable series of dry intervals lasting decades in the north of the region. The northern drought of the past 30 years is not the most severe in view of the past 500 years; however, the southern drought during the period from the 1960s to the 1980s may have been unprecedented. The dryness-wetness index (DWI) shows significant oscillations with periodicities of 9.5 and 20 years in the south and 10.5 and 25 years in the north. Longer periodicities in the DWI series include 160-170- and 70-80-yr oscillations in the north, and 100-150-yr oscillations in the south. The observed climate change could have implications for the construction and management of the SNWDP. The official approval and start of the hydro project was catalyzed by the severe multiyear drought of 1997-2003 in the north, and the operation and management of the project in the future will also be influenced by climate change-in particular by precipitation variability. This paper provides a preliminary discussion of the potential implications of observed climate change for the SNWDP. [ABSTRACT FROM AUTHOR]

The article discusses the scroll titled "Three Gorges Dam Migration" by artist Yun-Fei Ji, which depicts the Three Gorges Dam on the Yangzi River in China. Aspects of the artwork are explored including the use of calligraphic colophon, interpersonal contact among the piece's subjects, and the depiction of families moving away from the Badong area of China. Materials used in the creation of the scroll are presented including ink, bamboo, and silk. The article also presents a translation of the colophon text of the work, originally written in Chinese.

Baligang is a Neolithic site on a northern tributary of the middle Yangtze and provides a long archaeobotanical sequence from the Seventh Millennium BC upto the First Millennium BC. It provides evidence for developments in rice and millet agriculture influenced by shifting cultural affiliation with the north (Yangshao and Longshan) and south (Qujialing and Shijiahe) between 4300 and 1800 BC. This paper reports on plant macro-remains (seeds), from systematic flotation of 123 samples (1700 litres), producing more than 10,000 identifiable remains. The earliest Pre-Yangshao occupation of the sites provide evidence for cultivation of rice (Oryza sativa) between 6300–6700 BC. This rice appears already domesticated in on the basis of a dominance of non-shattering spikelet bases. However, in terms of grain size changes has not yet finished, as grains are still thinner than more recent domesaticated rice and are closer in grain shape to wild rices. This early rice was cultivated alongside collection of wild staple foods, especially acorns (Quercus/Lithicarpus sensu lato). In later periods the sites has evidence for mixed farming of both rice and millets (Setaria italica and Panicum miliaceum). Soybean appears on the site in the Shijiahe period (ca.2500 BC) and wheat (Triticum cf. aestivum) in the Late Longshan levels (2200–1800 BC). Weed flora suggests an intensification of rice agriculture over time with increasing evidence of wetland weeds. We interpret these data as indicating early opportunistic cultivation of alluvial floodplains and some rainfed rice, developing into more systematic and probably irrigated cultivation starting in the Yangshao period, which intensified in the Qujialing and Shijiahe period, before a shift back to an emphasis on millets with the Late Longshan cultural influence from the north. [ABSTRACT FROM AUTHOR]

By Hirschman-Herfindahl Index, the paper measures the spatial structure transformation of the Chinese container port system from the perspective of cargo flow in recent 13 years. It indicates that the spatial structure of container port system enters into 'the challenge of the periphery' phase as a whole, the decentralization of container flow become the mainstream tendency of the spatial variation of China's container port system; on the other hand, the spatial structure of container port system shows different characteristic in seven port regions, such as low-level equilibrium, single-gateway, multi-gateway and so on. It is a fact that multi-gateway port region of container port system has formed in Yangtze River Delta and Pearl River Delta region. Economic and foreign trade development, government macro-control and policy guidance, challenge of the periphery, network expansion of the terminal operators and shipping liners are the main driving forces for these new phenomena. [ABSTRACT FROM AUTHOR]

Heavy rainfall hit the Yangtze-Huai Rivers basin (YHRB) of east China several times during the pro-longed 2007 mei-yu season, causing the worst flood since 1954. There has been an urgent need for attaining and processing high-quality, kilometer-scale, hourly rainfall data in order to understand the mei-yu pre-cipitation processes, especially at the mesoß and smaller scales. In this paper, the authors describe the construction of the 0.07°-resolution gridded hourly rainfall analysis over the YHRB region during the 2007 mei-yu season that is based on surface reports at 555 national and 6572 regional automated weather sta-tions with an average resolution of about 7 km. The gridded hourly analysis is obtained using a modified Cressman-type objective analysis after applying strict quality control, including not only the commonly used internal temporal and spatial consistency and extreme value checks, but also verifications against mosaic radar reflectivity data. This analysis reveals many convectively generated finescale precipitation structures that could not be seen from the national station reports. A comprehensive quantitative as-sessment ensures the quality of the gridded hourly precipitation data. A comparison of this dataset with the U.S. Climate Prediction Center morphing technique (CMORPH) dataset on the same resolution suggests the dependence of the latter's performance on different rainfall intensity categories, with sub-stantial underestimation of the magnitude and width of the mei-yu rainband as well as the nocturnal and morning peak rainfall amounts, due mainly to its underestimating the occurrences of heavy rainfall (i.e., >10mmh-1). [ABSTRACT FROM AUTHOR]

Poyang Lake in Jiangxi Province is the largest freshwater lake in China and is historically a region of significant floods. Maximum annual lake stage and the number of severe flood events have increased during the past few decades because of levee construction that reduced the area available for floodwater storage. The most severe floods since 1950 occurred during 1954, 1973, 1983, 1995, and 1998. Each of these floods followed El Niño events that influence the Asian monsoon and that are directly linked to rainfall in the Changjiang (Yangtze River) basin. The 1954 flood was the largest ever recorded until the 1990s. That year the peak Changjiang stage at Hukou was 21.6 m, which was 1.6 m above the previous record high. The last major flood on the Changjiang was during 1998, when the peak Changjiang stage reached 22.5 m, higher than during 1954, even though peak discharge was lower. The most severe floods, including those in 1954 and 1998, require both 1) high rainfall and tributary discharge into Poyang Lake and 2) high Changjiang discharge and stage at Hukou that backflows into the lake or slows Poyang Lake drainage. Since gauging stations were established on the Changjiang, these conditions always occurred following an El Niño. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Engineering Geology & the Environment is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of Engineering Geology & the Environment is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of Engineering Geology & the Environment is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

By 9000 cal BP, the first sedentary villages, marking the Early Neolithic, are present in Northeast China, North China, and the Middle and Lower Yangtze regions, but plant and animal domesticates do not make a substantial contribution to subsistence until after several more millennia, when domesticated millet or rice agricultural production is finally in place. While archaeobotanical approaches have been the primary focus of recent studies, this paper looks specifically at the cultural developments in these four regions leading up to the emergence of agriculture in each. It is hypothesized that agriculture does not emerge independently in each of these regions but rather in interrelated steps through variable forms of interaction and information and social exchange within and between these regions. Interaction is currently evidenced through shared forms of material culture and by parallel and contemporaneous cultural developments. [ABSTRACT FROM AUTHOR]

In the past 10 years, flotation techniques have been introduced and implemented in Chinese archaeology. As a result, a tremendous quantity of plant remains have been recovered from archaeological sites located all over China. These plant remains include crops that might have been domesticated in China—such as rice, foxtail millet, broomcorn millet, and soybean—as well as crops that were introduced into China from other parts of world—such as wheat and barley. The new archaeobotanic data provide direct archaeological evidence for the study of the origins and development of agriculture in China. This paper attempts a synthesis of these new archaeobotanic data while presenting some new ideas about the origins and development of ancient agriculture in China, including the rice agriculture tradition that originated around the middle and lower Yangtze River areas; the dry-land agriculture tradition, with millets as major crops, centered in North China; and the ancient tropical agriculture tradition located in the tropical parts of China, where the major crops seem to be roots and tubers, such as taro. [ABSTRACT FROM AUTHOR]

The Jianghan Plain and the Dongting lake area, located in the middle reaches of the Yangtze River are famous for their abundant freshwater lakes. The lakes have undergone changes in size and number over thousands of years due to natural causes and human activities. The 20th century particularly, witnessed dramatic changes in the freshwater resources of this region. This paper traces and analyzes lake evolution in the middle reaches of the Yangtze River over the past century. Lakes greater than 0.1 km2 in size are mapped using Geographic Information System. Data is acquired and integrated from drainage network maps, relief maps, historical maps and remotely sensed images for different time periods. The results indicate that while there has been little change in the number of lakes over the past century, the lake area has experienced a dramatic decrease of 58.06%. The paper also examines the natural processes and human activities that may have contributed to the decrease in lake area. The results show that the decrease in total lake area appears to coincide with periods of rapid land reclamation in the middle reaches of the Yangtze River. Moreover, uncontrolled land reclamation activities can create an increase in sediment deposition in lakes thereby further reducing the lake size. Reduction of the lake area directly affects flood-control and has a negative ecological impact on the environment and on human life and property. [Copyright &y& Elsevier]

Abstract This paper develops a new paradigm to analyze the eco-efficiency of Yangtze River Economic Belt (YREB) in China and makes a first empirical attempt at examining whether the eco-efficiency in urban agglomerations (UA-s) outperform Non-urban agglomerations (Non-UA-s), or driving the Non-UA-s in promoting eco-efficiency using a dataset of 108 prefectural-level cities during 2003–2014. The main findings are as follows. First, the eco-efficiency of YREB gradually increases during the study period. Cities in UA-s with higher eco-efficiency experience an increasing spatial agglomeration while those in Non-UA-s show a slight downward shift. Second, in terms of eco-efficiency, both statistical test and econometrical test confirm that cities in UA-s outperform those in Non-UA-s. Third, the global and club convergence of eco-efficiency in YREB is ascertained. Forth, the eco-efficiency of UA-s exerts backwash effects on those in Non-UA-s, along with decreasing the convergence speed of eco-efficiency. Special issues are briefly discussed, lastly. Highlights • A new analysis paradigm is developed to explore the YREB's eco-efficiency. • Temporal-spatial evolution and empirical tests are conducted, indicating a proof that eco-efficiency in urban agglomerations outperform that in Non-urban agglomerations. • Urban agglomerations have backwash effects and slight constraints to Non-urban agglomerations in terms of eco-efficiency. • Some special issues are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Eutrophication is a world-wide environmental issue. Lake Taihu is a typical large, shallow, eutrophic lake located in delta of River Changjiang (Yangtze River). A large-scale ecological engineering experiment targeted at water quality improvement was implemented in Meiliang Bay, Lake Taihu. In this special issue, there are six papers related to water purification and algal bloom control techniques applied in this experiment. Four papers address the validity and efficiency of water quality improvement of this ecological engineering and one paper presents a similar but small-size ecological engineering. The others focus on macrophyte restoration, aquatic plant management and recycling exploitation. The editorial paper highlights the main results and conclusions from these papers. [Copyright &y& Elsevier]

This article investigates a series of projects for the improvement of shipping conditions of the Upper Yangzi in 1805-'40. The enterprise was undertaken by two Hankou merchants, one of whom published his 'Brief Account of the Taming of the Rapids'. An analysis of the detailed data of this source provides insights into navigation conditions and rates of environmental change on a major river, and into a major infrastructure project undertaken as merchant philanthropy. This paper proposes a perspective on water transport in pre-industrial China against a wider temporal and cultural backdrop, with a particular reference to private philanthropy as a set item within the moral economy. [ABSTRACT FROM AUTHOR]

Abstract  This paper presents a new kind of material for use in highway embankments in the soft soil of the Yangzi River delta. The experimental study was carried out first to evaluate the effectiveness of the proposed material, using different mixtures of river sand, cement and expanded polystyrene beads. This was confirmed by numerical modeling which indicated both its suitability as regards strength and a reduced settlement compared with the general lime stabilized soil embankments. The environmental advantage is that it utilized river sand which has to be removed to retain the profile of the river bed. [ABSTRACT FROM AUTHOR]

A new static-based method for damage detection of cable-stayed bridges using the changes in cable forces is presented in this paper. In recognizing the fact that damage incurring in bridge girders will cause a redistribution of forces in stay cables, the proposed method uses the measured changes in cable forces to detect the damage in bridge girders. In this method, the damage identification is formulated as an optimization problem in which the cable force error between measurement results and analytical model predictions is minimized. The sensitivities of cable forces with respect to the structural parameters of bridge girders for the linear and geometrically nonlinear bridge structures are obtained by using the direct differentiation method and the finite difference method, respectively, and are used to solve the optimization problem. Regularization technique is used to alleviate ill-conditioning in the solution course of the optimization problem. The validity of the method is illustrated by numerical studies of damage detection of the cable-stayed Sutong Bridge with a main span of 1,088 m. The effect of measurement noises and the number of measured cable forces on the accuracy of damage quantification is investigated. The proposed method correctly identifies the damage locations and damage magnitudes in bridge girders when using noise-free cable forces. It is also shown that structural damage can be quantified with acceptable accuracy in the case of low-level measurement noises and the damaged members being well spaced, and the identification accuracy is greatly improved when the forces in the cables connected to the damaged members are available for damage quantification. [ABSTRACT FROM AUTHOR]

The ability to extract mitochondrial and nuclear DNA from ancient remains has enabled the study of ancient DNA, a legitimate field for over 20 years now. Recently, Y chromosome genotyping has begun to be applied to ancient DNA. The Y chromosome haplogroup in East Asia has since caught the attention of molecular anthropologists, as it is one of the most ethnic-related genetic markers of the region. In this paper, the Y chromosome haplogroup of DNA from ancient East Asians was examined, in order to genetically link them to modern populations. Fifty-six human remains were sampled from five archaeological sites, primarily along the Yangtze River. Strict criteria were followed to eliminate potential contamination. Five SNPs from the Y chromosome were successfully amplified from most of the samples, with at least 62.5% of the samples belonging to the O haplogroup, similar to the frequency for modern East Asian populations. A high frequency of O1 was found in Liangzhu Culture sites around the mouth of the Yangtze River, linking this culture to modern Austronesian and Daic populations. A rare haplogroup, O3d, was found at the Daxi site in the middle reaches of the Yangtze River, indicating that the Daxi people might be the ancestors of modern Hmong-Mien populations, which show only small traces of O3d today. Noticeable genetic segregation was observed among the prehistoric cultures, demonstrating the genetic foundation of the multiple origins of the Chinese Civilization. [ABSTRACT FROM AUTHOR]

This paper explores the demographic impacts of the implementation of the "Grand Development in West China" policies and environmental rehabilitation projects in the upper reaches of the Yangtze River. It analyses the interaction between the environmental reconstruction and environment-related migration in this region. The intertwined nature of environmental, ethnic, and poverty problems not only bears negatively upon the "alleviation of poverty conducing to the accruement of wealth" of the poverty-stricken population, but also hinders the rehabilitation of the environment. It brings forth some opinions regarding improving the capacity of regional sustainable development through environmental migration. [ABSTRACT FROM AUTHOR]

The Yangtze River Economic Belt (YREB) is the prior region for achieving China’s strategic development with both economic and ecological goals. Since YREB covers more than 500 million people within a large area, the unbalanced urban sustainable development cannot be neglected. Different from the previous studies, this paper adopts an index of urban state carrying capacity (USCC) to assess the sustainable development in YREB. USCC can reflect the positive effects clearly, and evaluate the carrying capacity without the distortion from the opposite side. The assessment method combines the framework of Indicator-Benchmark Comparison (IBC) and the method of Analytical hieratical process (AHP), and sets up the indicator system for USCC from four perspectives. Based on the panel data for the years 2006–2014 in three scale levels, the analyses of temporal and spatial differentiation are conducted to discuss the unbalanced development in YREB. The results present that the eastern sub-UAs have much higher USCC values than the western ones significantly. The provincial cities and municipalities with higher USCC have strong impacts on their neighborhood cities around them. Further policies are suggested to support for other unbalanced sustainable development urban agglomerations like YREB. [ABSTRACT FROM AUTHOR]

Applying a parameterized directional distance function approach, this paper estimates the regional eco-efficiency and pollutants' marginal abatement costs in China based on provincial panel data covering the years 2003–2012. We find that China could potentially save capital, labor, land, energy and water by 18.07%, 11.47%, 11.20%, 12.28% and 11.19%, and reduce emissions of carbon dioxide (CO 2 ), household refuse and waste water by 11.75%, 11.02% and 11.46%, respectively, on condition that all provinces produced fully efficiently, The south and east coastal areas were the most eco-efficient, while the middle Yangtze River and southwest areas performed relatively poor. For the whole country, the average shadow prices of CO 2 , household refuse and waste water were 717.27 Yuan/tonne, 42,936.98 Yuan/tonne and 306.65 Yuan/tonne, respectively. The shadow price of CO 2 revealed significant regional disparities and that of household refuse showed a rapid increase throughout the study period. Our estimates suggest that policymakers should take measures to avoid ineffective capital investment and improve economic output efficiency in inland provinces, especially in the middle Yangtze River, northwest and southwest areas, and facilitate technological cooperation between developed and undeveloped areas. The regional heterogeneity and flexible price mechanism of various pollutants should be taken into consideration when making the reduction allocations among different areas. [ABSTRACT FROM AUTHOR]

Detailed studies on the spatiotemporal patterns of urban agglomeration in the Middle Yangtze River Basin (MYRB) are rare. This paper analyzed the spatiotemporal patterns of urbanization in the MYRB using multi-temporal remote sensing data circa 2000, 2008 and 2016 integrated with geographic information system (GIS) techniques and landscape analysis approaches. A multi-level analysis of the rate and intensity, type as well as the landscape changes of urban expansion at regional, prefectural and inner-city levels was performed. Results show that the MYRB experienced rapid urban expansion with an annual expansion rate of 3.199%, especially in the Chang-Zhu-Tan and Poyang Lake metropolitan areas. The small and medium cities presented faster urban expansion than the larger cities with annual growth rates three times the average level. Urban expansion within the three capital cities was further analyzed in detail. It is found that outlying expansion and edge-expansion were the dominant growth patterns at all the three levels. Although urbanization in the MYRB has a remarkable increase in the past sixteen years, its annual growth rate of urban land expansion has fallen behind the three other large urban agglomerations in China as a result. Finally, the spatial evolution of the socioeconomic structure of the MYRB was further explored. It indicated that urban land was distributed mainly along the "northwest-southeast" direction and that the economic spatial interactions among cities showed a pattern of "multi-polarization and fragmentation", which illustrates the weak radiative driving forces of the central cities. The MYRB urban agglomeration faces a great challenge to manage trades-offs between narrowing the intra-regional disparity and maintaining synergetic development among cities. [ABSTRACT FROM AUTHOR]

Several studies have indicated that glaciers in the Qinghai-Tibet plateau are thinning, resulting in reduced water supplies to major rivers such as the Yangtze, Yellow, Lancang, Indus, Ganges, Brahmaputra in China, and south Asia. Three rivers in the upstream of Yangtze River originate from glaciers around the Geladandong snow mountain group in central Tibet. Here we used elevation observations from Ice, Cloud, and land Elevation Satellite (ICESat) and reference elevations from a 3-arc-second digital elevation model (DEM) of Shuttle Radar Terrestrial Mission (SRTM), assisted with Landsat-7 images, to detect glacier elevation changes in the western (A), central (B), and eastern (C) regions of Geladandong. Robust fitting was used to determine rates of glacier elevation changes in regions with dense ICESat data, whereas a new method called rate averaging was employed to find rates in regions of low data density. The rate of elevation change was -0.158 ± 0.066 m·a-1 over 2003-2009 in the entire Geladandong and it was -0.176 ± 0.102 m·a-1 over 2003-2008 in Region C (by robust fitting). The rates in Regions A, B, and C were -0.418 ± 0.322 m·a-1 (2000-2009), -0.432 ± 0.020 m·a-1 (2000-2003), and -0.321 ± 0.139 m·a-1 (2000-2008) (by rate averaging). We used in situ hydroclimatic dataset to assess these negative rates: the glacier thinning was caused by temperature rises around Geladandong, based on the temperature records over 1979-2009, 1957-2013, and 1966-2013 at stations Tuotuohe, Wudaoliang, and Anduo. The thinning Geladandong glaciers led to increased discharges recorded at the river gauge stations Tuotuohe and Chumda over 1956-2012. An unabated Geladandong glacier melting will reduce its long-term water supply to the Yangtze River Basin, causing irreversible socioeconomic consequences and seriously degrading the ecological system of the Yangtze River Basin. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the velocity characteristics of compound rivers in mountain areas, featured with substantially different roughness between the main channel and floodplain. A series of flume experiments have been conducted to investigate the velocity distribution affected by different roughness in the main channel and its floodplain. The experimental data are analysed to obtain a new empirical formula to determine the velocity ratio between the main channel and the floodplain. In addition to the roughness, the ratio between the water depth in the main channel and the floodplain also affects the flow velocity. Therefore the velocity characteristics vary with the roughness and depth in the subsections of the compound channel. The new empirical formula is applied to estimate velocity in the upper reach of Yangtze River, in Chongqing, China. The calculated results are found to be consistent with the field measurements, demonstrating the potential of the formula for estimating velocity distribution in mountain rivers. [ABSTRACT FROM AUTHOR]

Scientific understanding of the evolution law of territorial space patterns and the ability to reveal the formation mechanism hold great significance for the sustainable utilization of territorial resources and the high-quality green development of the Yangtze River Economic Belt (YREB). In this study, we used the spatial chord diagram, landscape pattern index, and geographical probe to explore the evolution characteristics and formation mechanism of the territorial space pattern of the YREB from 2000 to 2020. The results showed the following: (1) The territorial space showed obvious geographical hierarchical distribution characteristics in the topographic gradient. Production and living space was dominant throughout the low and middle terrain region. Ecological space was dominant throughout the high-terrain regions. With the increase of altitude and slope, production and living space contracted, whereas ecological space areas expanded. (2) Since 2000, the territorial space has changed more dramatically. Over time, living space tended to increase, and production and ecological space tended to decrease, but ecological space was always dominant. In space, the geographical differentiation of territorial space was more obvious, and the pattern was relatively stable, with production space distributed primarily in the middle and lower reaches, living space distributed primarily in the lower reaches, and ecological space distributed primarily in the middle and upper reaches. The inter-transformation between territorial spaces was more frequent, and the transformation trajectory was diversified. (3) The fragmentation, heterogeneity, and dispersion of territorial space landscape patches throughout the whole region increased, and the balance and diversity of territorial space utilization improved. (4) Natural factors have continued to weaken the intensity of their effect on territorial space. Human factors gradually increased the extent of their interference in the territorial space. There are significant differences in the extent of the role of these different factors on the territorial space of the whole region and each basin. Natural and human factors jointly promoted the formation and development of the territorial space pattern. [ABSTRACT FROM AUTHOR]

This paper examined the sediment gain and loss in the river mouth reach of the Yangtze River by considering sediment load from the local tributaries, erosion/accretion of the river course, impacts of sand mining, and water extraction. A quantitative estimation of the contribution of the river mouth reach to the sediment load of the Yangtze River was conducted before and after impoundment of the Three Gorges Dam (TGD) in 2003. The results showed that a net sediment load loss of 1.78 million ton/yr (Mt/yr) occurred from 1965 to 2002 in the study area. The contribution of this reach to the sediment discharge into the sea is not as high as what was expected before the TGD. With impoundment of the TGD, channel deposition (29.90 Mt/yr) and a net sediment loss of 30.89 Mt/yr occurred in the river mouth reach from 2003 to 2012. The river mouth reach has acted as a sink but not a source of sediment since impoundment of the TGD, which has exacerbated the decrease in sediment load. Technologies should be advanced to measure changes in river channel morphology, as well as in water and sediment discharges at the river mouth reach. [ABSTRACT FROM AUTHOR]

Continuous rigid-frame bridges are usually used in building bridges with long span and high piers. It is characterized by the consolidation between piers and beams in the middle of bridge piers and flexible bridge piers in the lower part. Among all the factors, curvature has the most obvious influence on the stress of curved continuous rigid-frame bridge, because of which, the curved beam bridge produces coupling effect of bending moment and receives complicated stress, leading to the deformation such as torsion and displacement of radial direction. No matter it is the castscaffold construction or cantilever construction, for continuous rigid-frame bridges, considering that after the long term creep of concrete, structure stress tends to be in a drop-frame state, so it is necessary to know the mechanical properties of the finished bridge. Taking the Chongqing Yangtze River Bridge as an example, this paper mainly analyzes the internal forces and deformations of a finished curved continuotus rigid-frame bridge by establishing a spatial finite element model with Midas Civil 2006 software and by changing the model's radius of curvature. The results show that as the curvature increases, the vertical deformation and torsion angle of the long-span curved continuous rigid-frame bridge are both reduced under the effect of a dead load and prestressed load, presenting mechanical properties of bridge, namely, "coupling effect of bending moment". In the model analyzed, the deformation of the bridge in the transverse direction also behaves a trend of gradual decrease with an increase in radius of curvature with the range 500-2000 m. [ABSTRACT FROM AUTHOR]

Abstract: This paper aims to develop a novel hybrid model for assessing landslide susceptibility at the regional scale using multisource data to produce a landslide susceptibility map of the Zigui–Badong area near the Three Gorges Reservoir, China. This area is subject to anthropogenic influences because the reservoir's water level fluctuates cyclically between 145 and 175m; in addition, the area suffers from extreme rainfall events due to the local climate. The area has experienced significant and widespread landslide events in recent years. In our study, a novel hybrid model is proposed to produce landslide susceptibility maps using geographical information systems (GIS) and remote sensing. The hybrid model is based on rough set (RS) theory and a support vector machine (SVM). RS theory is employed as an attribute reduction tool to identify the significant environmental parameters of a landslide, and an SVM is used to predict landslide susceptibility. Four data domains were considered in this research: geological, geomorphological, hydrology, and land cover. The original group of 20 environmental parameters and 202 landslides were used as the inputs to produce a landslide susceptibility map. According to the map, 19.7% of the study area was identified as medium- and high-susceptibility zones encompassing 89.5% of the historical landslides. The results indicate high levels of landslide hazard in and around the main inhabited areas, such as Badong County and other towns, as well as in rural residential areas and transportation areas along the Yangtze River and its tributaries. The predicted map indicates a good correlation between the classified high hazard areas and slope failures confirmed in the field. Furthermore, the quality of the proposed model was comprehensively evaluated, including the degree of model fit, the robustness of the model, the uncertainty associated with the probabilistic estimate, and the model prediction skill. The proposed model was also compared with the general SVM, which demonstrated that the hybrid model has superior prediction skill and higher reliability and confirmed the usefulness of the proposed model for landslide susceptibility mapping at a regional scale. [Copyright &y& Elsevier]

Based on the comprehensive evaluation method, a comprehensive urban ecological carrying capacity (UECC) evaluation system is established. It includes ecological support, ecological resilience, and ecological pressure. Multiscale geographically weighted regression (MGWR) was used to conduct a thorough examination of the spatial and temporal patterns, and the factors that influenced the UECC of 286 prefecture-level cities in China from 2010 to 2019. The results show that (1) China's UECC index ranges from 0.0233 to 0.2811 in 2019, which is still at a low level. (2) The spatial distribution is relatively stable: high-value agglomerations of UECC are distributed primarily in the Yangtze River Delta and Pearl River Delta, while low-value agglomerations are primarily distributed in the regions in the Central Plains. (3) All influencing factors have a positive effect on the improvement of UECC and are heterogeneous in spatial distribution. Lastly, this paper gives corresponding suggestions, so that governments can formulate differentiated policies and effectively improve UECC. [ABSTRACT FROM AUTHOR]

Abstract: Effective flood management measures incorporate the flood mitigation functions of natural ecosystems, but the exact functions and effects of forests, grasslands and other ecosystems in mitigating floods are not clearly understood. In this paper, a flood mitigation assessment model was established based on the Soil Conservation Service (SCS) method, and the function and potential capacity of ecosystems for mitigating flooding in the Upper Yangtze River Basin (UYRB) were assessed. The monetary value of flood mitigation service was calculated by formulating an exponential function with respect to the amount of storm and flood damage. The results showed that ecosystems in the UYRB reduced flooding by a total of 42.8 billion cubic meters. Statistical equations developed for the amount of storm and flood damage gave an average of 6.479 billion RMB Yuan as the value of ecosystem flood mitigation in the UYRB. Despite their small cost, ecosystems have the potential to reduce flood damage by more than half, an indication of the important role of ecological systems in flood management. This approach can be used to identify high-value areas for ecological protection, and also to provide the governments at various levels with important information for decision-making related to integrated flood management. [Copyright &y& Elsevier]

The annual variability of ichthyoplankton in the Yangtze River estuary, located at the junction of the East China Sea and the Yellow Sea, on the continental shelf at the western rim of the Pacific Ocean, was studied using vertical tows at twenty stations from August 2002 to August 2009. Basic oceanographic parameters such as temperature and salinity were also measured to evaluate their relationship to the abundance of ichthyoplankton. The eggs or larvae of a total of 34 fish species were present in the samples. Only 8 species were found to occur during every year. Engraulis japonicus and Stolephorus commersonii eggs, as well as Coilia mystus and Stolephorus commersonii larvae, were highly abundant during this period. Additionally, water storage in the Three Gorges Reservoir, which began in June 2003, had significant effects on the abundance of estuarine species, as well as on the composition and diversity of ichthyoplankton; this became evident when these values were compared to the findings from 2002. The number of species (species richness) and abundance of each species varied among the stations relative to the salinity in the estuary during the study period. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the variability of daily temperature in the Yangtze River Delta (YRD) for the period 1958–2007 was investigated by selecting three typical temperature variables (daily minimum, mean and maximum temperatures) and the diurnal temperature range (DTR). Three variability patterns of daily mean temperature and two variability patterns of daily minimum and maximum temperatures were first classed, and then statistical properties of three temperature variables in 1958–1985 and 1986–2007 were analyzed. After that, temporal trends of three temperature variables and DTR were detected. Finally, the impacts of urbanization on the variability of daily temperature were investigated. Results indicate that: (1) daily mean temperature shows more complex variability than daily minimum and maximum temperatures; (2) in 1986–2007 three temperature variables have bigger mean values but smaller C v (coefficient of variance) values, and are more close to normal probability distribution; (3) three temperature variables show positive trends in 1986–2007, and the increase of daily mean temperature is more due to the increase of daily minimum temperature in the northern YRD but due to daily maximum temperature in the mid and southern YRD; (4) in the mid and southern YRD, daily maximum temperature has bigger increasing magnitude than daily minimum temperature in 1986–2007, causing positive trend of DTR; and (5) rapid urbanization causes normal distribution of three temperature variables, and notably increasing magnitude of daily temperature and DTR in 1986–2007 at the lower reaches of the Yangtze River and the Hangzhou Bay. [Copyright &y& Elsevier]

Abstract: the river of Yangtze River in Chongqing area is continuous curved. Hydrology and channel situation is complex, and the transportation is busy. With the increasing of shipments of hazardous chemicals year by year, oil spill accident risk is rising. So establishment of three-dimensional virtual simulation of oil spill and its application in decision-making has become an urgent task. This paper detailed the process of three-dimensional virtual simulation of oil spill and established a system of three-dimensional virtual Simulation of oil spill of Yangtze River in Chongqing area by establishing an oil spill model of the Chongqing area based on oil particles model, and the system has been used in emergency decision to provide assistance for the oil spill response. [Copyright &y& Elsevier]

Abstract: In recent years a large number of floods occurred in the Dongting Lake region, China, and flood prevention and control have become a focus in the middle Yangtze River. How to use the dispersed sub-fast-flood storage area in Dongting basin rationally and control water level and flow process will improve flood prevention ability. In this paper an improved systematic flood simulation method coupling one and two-dimensional hydraulic model is established aiming at special area. The flood evolution process, different flood discharge scale, flood storage and embanking effect are simulated according to the changing spatial gate position and extra flood magnanimity for the typical hydrologic years. An optimized scheduling scheme by using the parallel algorithm and numerical computing method is preferred in different flood periods. The research results indicate the optimized flood diversion gate and operation scheme in three shunts river system will directly control the water level in the whole lake region. The research results provide practical basis for systematic floods control and is helpful to assess flood disaster in Yangtze River basin. [Copyright &y& Elsevier]

Abstract: Suzhou is located at the lower reaches of the Yangtze River in southeastern Jiangsu, China. It is part of the Su-Xi-Chang area including Suzhou, Wuxi and Changzhou. As one of the most developed areas in China, this region has suffered from severe land subsidence caused by extensive groundwater exploitation since 1980s. The land subsidence was controlled by prohibition of groundwater exploration in the past several years. However, the surface water pollution prompted a new task of how to sustainably utilize the groundwater resource, especially to satisfy the emergency demands of water supply. In this paper, we took Suzhou as a representative case to discuss how to develop groundwater resources while controlling the land subsidence. The relationship between the deformation and the groundwater level was analyzed, with focus on the deformation features after the period of groundwater exploitation ban. The results confirmed the conclusion by Shi et al. (2007, 2008a): even in the period of rising groundwater level, same units may manifest different deformation characteristics, such as elasticity, elasto-plasticity, and visco-elasto-plasticity, at different locations of the cone of depression. A land subsidence model that couples a 3-D groundwater model and a 1-D deformation model was developed to simulate the groundwater level and deformation. A high-resolution local grid (child model) for Suzhou was built based on the regional land subsidence model of Su-Xi-Chang area by Wu et al. (2009). The model was used for a number of predictive scenarios up to the year of 2012 to examine how to develop sustainable use of groundwater resources under the conditions of land subsidence control. Our results indicated that about 3.08×107 m3/a groundwater could be provided as emergency and standby water source while meeting the land subsidence control target of 10mm/a. [Copyright &y& Elsevier]

Abstract: Ecological protection of the Three Gorge Reservoir wetland would influence the development of the Yangtze River area and even the whole of northern China. This paper studies the current situation of the Three Gorge Reservoir wetland, and analysising the main threats which the reservoir area facing. And then we proposed ecological wetland protection measures from planning, design, management system innovation, and the public awareness, in hope to improve the protection and management level of the Three Gorge Reservoir wetland, and leading to deep thinking. [Copyright &y& Elsevier]

Abstract: For centuries, Human beings developed a lot of water conservancy projects, these projects have played a significant role in civilizing process and brought serious negative impacts to environment as well. This paper research the impact of human activities to river ecosystem among the Yangtze River. Through data analysis of manual activities to river bend, straighten and water flows, we try to discuss the interference effect to ecological system on the lower Jingjiang of Yangtze River. Meanwhile, the study attempts put some forward countermeasures to river restoration. [Copyright &y& Elsevier]