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In this paper, we examine the genetic diversity, population structure and demographic history of Acrossocheilus yunnanensis inferred from four mitochondrial gene sequences. Twenty-two haplotypes were identified for A. yunnanensis. The total haplotype and nucleotide diversities of A. yunnanensis are 0.9206 and 0.024654, respectively. The monophyly of the haplotypes is supported by all phylogenetic analyses. All the haplotypes can be divided into four major lineages. The results of AMOVA and SAMOVA suggest that the best grouping pattern is to divide four groups, and that most of the variation of genetic divergence is present among these groups. The population expansion of A. yunnanensis is not supported by the analyses of population demography. Our results revealing the genetic background of A. yunnanensis will prove helpful in protecting its genetic diversity and utilizing this resource in a reasonable manner. [ABSTRACT FROM AUTHOR]

Remote sensing technology has been widely used in many fields. But most of the applications cannot get the information with high reliability and high accuracy in large scale, especially for the applications using automatic interpretation methods. We have designed an application-oriented technology system (PIR) composed of a series of accurate interpretation techniques, which can get over 85% correctness in Water Resource Management from the view of photogrammetry and expert knowledge. The techniques compose of the spatial positioning techniques from the view of photogrammetry, the feature interpretation techniques from the view of expert knowledge, and the rationality analysis techniques from the view of data mining. Each interpreted polygon is accurate enough to be applied to the accuracy sensitive projects, such as the Three Gorge Project and the South - to - North Water Diversion Project. In this paper, we present several remote sensing applications with high reliability in Changjiang Water Resource Management, including water pollution investigation, illegal construction inspection, and water conservation monitoring, etc. [ABSTRACT FROM AUTHOR]

In this paper, we present ship-based Multi- Axis Differential Optical Absorption Spectroscopy (MAXDOAS) measurements of tropospheric trace gases' distribution along the Yangtze River during winter 2015. The measurements were performed along the Yangtze River between Shanghai andWuhan, covering major industrial areas in eastern China. Tropospheric vertical column densities (VCDs) of nitrogen dioxide (NO2), sulfur dioxide (SO2), and formaldehyde (HCHO) were retrieved using the air mass factor calculated by the radiative transfer model. Enhanced tropospheric NO2 and SO2 VCDs were detected over downwind areas of industrial zones over the Yangtze River. In addition, spatial distributions of atmospheric pollutants are strongly affected by meteorological conditions; i.e., positive correlations were found between concentration of pollutants and wind speed over these areas, indicating strong influence of transportation of pollutants from high-emission upwind areas along the Yangtze River. Comparison of tropospheric NO2 VCDs between ship-based MAX-DOAS and Ozone Monitoring Instrument (OMI) satellite observations shows good agreement with each other, with a Pearson correlation coefficient (R) of 0.82. In this study, the NO2 / S± ratio was used to estimate the relative contributions of industrial sources and vehicle emissions to ambient NO2 levels. Analysis results of the NO2 / SO2 ratio show a higher contribution of industrial industrial NO2 emissions in Jiangsu Province, while NO2 levels in Jiangxi and Hubei provinces are mainly related to vehicle emissions. These results indicate that different pollution control strategies should be applied in different provinces. In addition, multiple linear regression analysis of ambient carbon monoxide (CO) and odd oxygen (Ox) indicated that the primary emission and secondary formation of HCHO contribute 54.4±3.7% and 39.3±4.3% to the ambient HCHO, respectively. The largest contribution from primary emissions in winter suggested that photochemically induced secondary formation of HCHO is reduced due to lower solar irradiance in winter. Our findings provide an improved understanding of major pollution sources along the eastern part of the Yangtze River which are useful for designing specific air pollution control policies. [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]

Solar radiation is the principal and fundamental energy for many physical, chemical and biological processes. Estimation of solar radiation by Ångström-Prescott (A-P) model from sunshine duration is common employed. In this paper, the original linear A-P model and four commonly used modification models (quadratic, cubic, power and logarithmic functions) are comparatively studied. It is found that the linear, second and cubic models give very similar goodness of fit, and the linear model is recommended due to its greater simplicity and convenience. The A-P model parameter a, sum a + b correlate most significantly with altitude. Based on these correlations, the deterministic equations of parameters a and b are proposed. Consequently, the A-P model with the estimated parameters by deterministic equations is used to estimate solar radiation, and it gives good performance with the RMSE < 1.7 MJ m-2, RRMSE < 20% and R² > 0.89. It is therefore recommended to use these equations to determine the A-P parameters in Yangtze River basin in China, and it is believed particularly useful for the site where lacks of the measured solar radiation data for calibration. [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]

Abstract: In the western Yangtze Block, widespread Mesoproterozoic to Neoproterozoic rocks are the key to understanding the Precambrian tectonic‐magmatic evolution of the region. However, their petrogenesis and tectonic setting are still controversial. In this paper, zircon U‐Pb ages, Sm‐Nd isotopic and whole‐rock geochemical data are reported from selected fresh samples in the southern Dechang county, southwestern China, in order to constrain their emplacement age and magma source, as well as their petrogenesis and tectonic setting. They are mainly composed of biotite monzogranite, monzonitic granite, biotite granodiorites, and quartz diorite. Two ages of 1055 ± 43 Ma and 837.6 ± 3.8 Ma were obtained through zircon U‐Pb dating by LA‐ICP‐MS and LA‐MC‐ICP‐MS, respectively. According to their major element compositions, the Grenville‐age granites are peraluminous calc‐alkaline series calcic S‐type granite. In contrast, the mid‐Neoproterozoic granites are metaluminous calc‐alkaline series alkalic I‐type granite. Furthermore, the S‐type granites are enriched in LREEs relative to HREEs with (La/Yb)N ratios of 3.85–18.56 and underwent major fractionation with strongly negative Eu anomalies (Eu/Eu* = 0.38–0.66). In the MORB‐normalized trace element variation diagram, all the samples are enriched in Ce and large ion lithophile elements such as Rb, Th, and K, and depleted in high field strength elements such as Nb, and Ti, with negative Sr and Ti anomalies. The I‐type granites are enriched in LREEs with slight negative Eu anomalies (Eu/Eu* = 0.83–0.93). They are characterized by the enrichment of highly incompatible elements (such as K, Rb, Ba, Th) and LREEs, relative to MORB. Neodymium isotopic data show that the S‐type granites display 143Nd/144Nd values of 0.51241–0.51256, and have εNd (t = 1055 Ma) values of (−3.29) to (−3.81). Calculated tDM ages yield values from 1.87 to 1.91 Ga with the tDM.2stg ages of 1.86 to 1.9 Ga. The I‐type granites have 143Nd/144Nd ratios between 0.51192 and 0.51195, corresponding to initial εNd (t = 837 Ma) values of 1.22 to 5.63. Calculated tDM ages yield values from 1.0 to 1.38 Ga and the tDM.2stg ages yield values from 0.99 to 1.06 Ga. The S‐type granites are distinguished as syn‐collision granite, whereas the I‐type granites were formed as arc magmas according to the Rb‐(Yb+Ta) and R1‐R2 tectonic discrimination diagrams. To conclude, there are two types of spatially associated granite, the Mesoproterozoic S‐type granite which were derived from re‐melting of upper crustal mudstone and/or clastics and resulted from the convergence of two continental plates, and the mid‐Neoproterozoic I‐type granite which formed in continental arc and resulted from mantle‐derived magma mixed crust material, in the western Yangtze Block. Furthermore, we suggest that collision between the Yangtze and Cathaysia blocks occurred at about 1055 Ma, and caused the S‐type granite. The I‐type granite related to the subduction of oceanic lithosphere eastward underneath the Yangtze Block in the mid‐Neoproterozoic. [ABSTRACT FROM AUTHOR]

The widely developed black shales on the Yangtze Platform recorded palaeoceanographic environment information during the Ediacaran–Cambrian transition. This paper describes an integrated geochemical study of rare earth elements (REEs), redox‐sensitive trace elements (RSTEs), and total organic carbon (TOC) contents in Ediacaran–Cambrian black shales at Daotuo, northeastern Guizhou Province, South China. Integrated RSTE data from the Daotuo area, in combination with previously published Fe speciation and Mo‐based proxies from another six sections (Shatan, Jiulongwan, Zhongling, Yangjiaping, Longbizui and Wuhe), suggest three major periods of water euxinia during the Ediacaran–Cambrian transition. Under these conditions, organic matter and RSTEs experienced various levels of enrichment in the black shales, especially in the lower Jiumenchong Formation. Given the patterns of Mo‐U covariations, metal‐oxyhydroxide particulate shuttles may have operated during the black shale deposition of the Doushantuo Formation (Member II) at Daotuo. Conspicuously, the upper slope water was oxic‐dysoxic during the earliest Cambrian, as determined by the REE, RSTE data and sedimentological characteristics of the Liuchapo Formation and the basal Jiumenchong Formation. The generally low RSTE concentrations in the Bianmachong Formation black shales (Cambrian Series 2, end of Stage 3) suggest a persistently oxic water column in upper slope settings. The coincidence between the marine oxygenation and the development of the ecosystem likely indicates the galvanizing effects of enhanced oxygen and biological element content on the fauna during the Ediacaran–Cambrian transition. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

To explore the public's risk perception and its causes and effects, it would be helpful to understand the basis for the public's disaster alleviation decisions and improve the effectiveness of risk communication. This paper analyses the relationship between the public's trust and risk perception by investigating the motives for trust building and the effects on public's flood risk perception in an area along the middle and lower reaches of Yangtze River. The objects of trust are disaster alleviation measures of monitoring and early warning, flood control projects, and disaster event management. The study data were obtained by conducting household interviews. The major conclusions are: (1) Public's trust in monitoring and early warning as well as in flood control projects is greater than the one in disaster event management. Trust has changed the public's assessment of flood risk and enhanced public confidence in disaster handling. Meanwhile, it reduces the propensity to adopt long-term preparation against disasters. Therefore, the public needs guidance in recognising the limits and validity of scientific and technological capabilities. (2) Public's trust is the product of not only individual psychological processes but also the external regional flood risk and social psychological characteristics. The levels of trust vary in different regions. Therefore, risk communication should be conducted according to regional characteristics. [ABSTRACT FROM AUTHOR]

Exploring the determinant between climate change and ecological restoration for streamflow dynamics is a significant issue in global change research and is essential for restoration policy assessment and climate change adaptation. In this paper, the combination of elasticity method and Budyko framework was applied with the meteorological and hydrological data from 1980 to 2014. The variability and variation of streamflow were explained by individual elasticity coefficient and contribution of climate change and ecological restoration between 1980-1999 and 2000-2014. Results showed that streamflow was more sensitive to climate change in the Yellow River source (YER) than in the Yangtze River source (YZR). Ecological restoration was positively correlated with the variability of streamflow in YER with 7.38% relative change in elasticity coefficients, while it was opposite trend in YZR with a relative change of − 7.41%. However, the impacts of climate change and ecological restoration on the variation of streamflow were not consistent with the variability. In YER, ecological restoration dominated the streamflow reduction with a contribution of 82.43%, whereas, in YZR, climate change mainly contributed to the streamflow increase which could explain 123.72% and the precipitation was the major contributor. By analysis, the difference in two catchments might result from the spatial heterogeneity of precipitation conditions and land use/cover change, especially the conversion of grassland. The results suggest that the implementation of ecological recovery should consider the difference of streamflow change in response to ecological restoration and climate change for the sustainability of water resources. [ABSTRACT FROM AUTHOR]

Groundings are frequently occurring accidents that pose a serious risk in inland waterways. This paper proposes a flexible decision-support solution for grounded ships in the Yangtze River. The basis of the proposed method is to develop an influence diagram based on a three-layer decision-making framework, to consider the effectiveness of the intervention measures by adding two nodes and establishing the associated conditional probability tables, and to merge the influence diagram and the intervention measures as a flexible decision-support solution. The merits of the proposed method include the intuitive representation of how the influencing factors affect the alternatives using a graphical structure, the flexibility to implement and to consider the intervention measures for grounded ships, and the ability to deal with uncertainty in both numerical data and qualitative information. The results of the case study showed that it is unanimous with the real situations and the intervention measures should be considered to make effective and accurate decision-making for grounding ships. Consequently, the method presented in this paper provides a practical and flexible decision-support solution for grounded ships. [ABSTRACT FROM AUTHOR]

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Mapping water quality change is helpful in the study of the water environment of a region. Using visual methods, interpretation of water condition and pollution issues can be intuitive and easy to understand. In this paper, we present a map to represent the spatial and temporal variation of water quality change in the Yangtze River during the period from 2006 to 2015. The calendar view was developed to explore the water quality condition and water pollutants for sections of the Yangtze River. A "W" construction was proposed to arrange the weekly water quality data in a continuous logic, and qualitative colors were designed to identify the change in major pollutants throughout the period. This map provides a promising visual analytical approach to investigate the water quality status and reveal the spatial and temporal patterns of water quality change in the Yangtze River. [ABSTRACT FROM AUTHOR]

This study examines the making of local climate governance in the Chinese setting where central-local inter-governmental relations continue to play critical part in almost every policy domain. Through analysing the climate responses of the three provincial-level governments at the Yangtze River Delta (YRD), the paper argues that the process of “experimentation under hierarchy” is relevant to understanding the evolving of the subnational climate regime in the YRD region. We find the preponderance of the central authorities in initiating national climate strategies and galvanising responses at the local level. Meanwhile, provincial governments have been able to leverage climate plans and actions to achieve their own gains. These findings suggest that any optimism about subnational climate activism in a Chinese setting has to be mixed with caution. In fact, the shadow of hierarchical authority structure lingers and plays important part in the initiation of subnational response and spurring climate responses and innovations from below. [ABSTRACT FROM AUTHOR]

The study aims to investigate the heterogeneity of the Yangtze River's impact on housing prices, using the data of 12,325 residential transactions within 8 kilometers of the Yangtze River in Wuhan, based on submarkets divided according to geographical location and buyer groups. The kernel density plots reveal that properties near the Yangtze River have the highest price and the lowest density, while properties further away from the river exhibit the opposite trend. Then the Spatial Generalized Additive Model and the Spatial Quantile Generalized Additive Model show the following results, respectively: (1) The Yangtze River has an influence range of roughly 5 kilometers on adjacent dwellings, with an average impact of 0.035%. However, within the chosen geographical interval, the impact rises from 1.582% to 2.072%. (2) The Yangtze River has the greatest impact on middle-priced houses, followed by high-priced houses, and the least impact on low-priced houses. (3) The Spatial Generalized Additive Model and the Spatial Quantile Generalized Additive Model have been proven to be effective at capturing spatial and temporal impacts on data. In conclusion, this article advises that the government should pay more attention to non-central locations with limited natural resources. [ABSTRACT FROM AUTHOR]

Non-heading Chinese cabbage, a variety of Brassica campestris, is an important vegetable crop in the Yangtze River Basin of China. However, the immaturity of its stable transformation system and its low transformation efficiency limit gene function research on non-heading Chinese cabbage. Agrobacterium rhizogenes-mediated (ARM) transgenic technology is a rapid and effective transformation method that has not yet been established for non-heading Chinese cabbage plants. Here, we optimized conventional ARM approaches (one-step and two-step transformation methods) suitable for living non-heading Chinese cabbage plants in nonsterile environments. Transgenic roots in composite non-heading Chinese cabbage plants were identified using phenotypic detection, fluorescence observation, and PCR analysis. The transformation efficiency of a two-step method on four five-day-old non-heading Chinese cabbage seedlings (Suzhouqing, Huangmeigui, Wuyueman, and Sijiu Caixin) was 43.33%e51.09%, whereas using the stout hypocotyl resulted in a transformation efficiency of 54.88% for the 30-day-old Sijiu Caixin. The one-step method outperformed the two-step method; the transformation efficiency of different varieties was above 60%, and both methods can be used to obtain transgenic roots for functional studies within one month. Finally, optimized ARM transformation methods can easily, quickly, and effectively produce composite non-heading Chinese cabbage plants with transgenic roots, providing a reliable foundation for gene function research and non-heading Chinese cabbage genetic improvement breeding. [ABSTRACT FROM AUTHOR]

Recent interpretations of the archaeology of domesticated rice evolution and the development of agriculture in the Lower Yangzi Valley are being informed by new genetic, palaeoenvironmental, archaeological and archaeobotanical data. This paper explores current views on early rice production in the region and attempts to expand the discourse to provoke exploration of new and modified questions. Rice-specific botanical through large-scale ecological issues and causality are examined. This paper argues that understanding rice domestication and production, although important, should not be the exclusive goal of research on early agriculture in the Yangzi Valley. Despite the preliminary nature of the investigations at Kuahuqiao (c. 8000–7000 cal. BP), evidence of resource management, and potential domesticated resources or their ancestors that includes pig (Sus scrofa), peach (Prunus persica), apricot (P. armeniaca), Japanese apricot (P. mume), foxnut (Euryale ferox) and water chestnut (Trapa spp.) underscore the need to broaden the scope of inquiry on early food/resource production. The complexities of the archaeological and environmental record in the Yangzi valley indicate that nuanced, complex explanations for rice domestication and agricultural origins rather than deterministic, single cause explanations are necessary in order to move forward. [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.

The present paper provides a scientific assessment of the inter-decadal variability of the Asian summer monsoon and its significant effect on precipitation patterns in China. The paper consists of four parts. The first part shows the observed inter-decadal weakening of the Asian summer monsoon since the end of 1970s. The second part describes the impact of the weakening Asian summer monsoon on precipitation in China, which caused the major monsoon rainbelt to shift southward from North China to South China over about 30 years, with a 60-80 oscillation dominating. The third part projects the future change of the Asian summer monsoon in the warmer climate by using IPCC AR4 climate models. It has been found that major monsoon rainfall belts in East Asia will move northward in the 2040s, with summer precipitation in North China increasing considerably and stably. Finally, in the fourth part, the implication of the adaptation to the above climate change and related water management will be discussed including the water transport engineering project from the Yangtze River to the Yellow River and North China. [ABSTRACT FROM AUTHOR]

Recently, increasing nutrient (i.e., nitrogen and phosphorus) concentrations have been observed in the surface water of many countries and this nonpoint source (NPS) pollution has become an important factor in the deterioration of water quality in the upper reach of the Yangtze River Basin. In this paper, the NPS pollution loads in the upper reach of Yangtze River Basin in the year 2000 were estimated using export coefficient model and remote sensing techniques. The spatial distributions of the NPS loads within the watershed were then displayed using geographical information system. Results indicated that the total nitrogen load was 1.947×106 t and the total phosphorus load was 8.364×104 t. Important source areas for the nutrients were croplands in the Jinsha R. and Jialing R. watershed, as well as the Chongqing municipality. [ABSTRACT FROM AUTHOR]

Hedgerow intercropping systems were introduced in China in early 1990s. Achievements in research and extension of contour hedgerow intercropping in China during the past 15 years are reviewed here. Results reported in over 70 published papers have shown that hedgerow intercropping contributes to soil and water conservation, soil fertility amelioration, land productivity improvement, bioterrace formation, and gives more options for income generation based on local resources in mountain areas. Research and demonstration works on contour hedgerow systems have achieved success by integrating local resources and needs into the system, especially in the dry valleys of the upper reaches of the Yangtze River, and the Three Gorges region. Contour hedgerow intercropping has attracted the attention of researchers, policy-makers, and farmers, and has been taken as an alternative to implementation of the Grain for Green policy, and ecological reconstruction and restoration today. To date, hedgerow intercropping has been demonstrated and applied practically on sloping land in more than six provinces of China, particularly Sichuan, Guizhou, Shanxi, Shaanxi, as well as in the Three Gorges region of Chongqing and Hubei Province. The intercropping system has also been practiced as an optimized technology for conserving farming on sloping lands, improving cash income, and reducing agricultural risks in depressed mountainous regions in southwest and northern China over recent years. Some misunderstandings and problems in studies and extension of the system in China are summarized and clarified, and some recommendations for further research and expansion of the system are also presented in this paper. [ABSTRACT FROM AUTHOR]

The middle reaches of the Yangtze River region (MRYRR) are China’s first trans-regional urban agglomeration, located in the center of the Yangtze River Economic Belt. The MRYRR is an important ecological reserve, and its land cover changes are affected by both socio-economic development and geographical environment. In this paper, Landsat ETM/TM/OLI remote sensing images were used to monitor land use and landscape patterns from 1990 to 2015. Through supervised classification, land use transfer matrix, landscape pattern metrics and correlation analysis, the spatialtemporal patterns of land use change and its relationship with socio-economic in the study area were revealed. The results showed that: (1) the main land use types in the study area were cropland (CL) and forestland (FL), accounting for more than three-quarters of the study area. During the study period, built-up land (BL) increased, CL decreased, FL increased first and then decreased; (2) the BL expanded mainly by occupying CL and FL, and regional landscape pattern was gradually fragmented, with complex patch shape and increasing diversity and heterogeneity. Among them, the BL is gradually gathered, and the FL and CL are gradually fragmented; (3) in the past 25 years, the urbanization process in this region has been obvious, and the Gross Domestic Product (GDP) has increased by 36 times. The socioeconomic variables were positively correlated with BL, orchard (OL) and Shannon diversity index (SHID), and negatively correlated with CL, Wasteland (WL), mean patch size (MPS) and contagion size (CONTAG). The results showed that the urbanization development has a great impact on the region, and the ecological protection task is still challenging. It is necessary to protect high-quality cropland and draw a red line for ecological protection. We should strengthen the construction of ecological corridors and ecological nodes to adapt to regional sustainable development. [ABSTRACT FROM AUTHOR]

Frequently occurring flood disasters caused by extreme climate and urbanization processes have become the most common natural hazard and pose a great threat to human society. Therefore, urban flood risk assessment is of great significance for disaster mitigation and prevention. In this paper, the analytic hierarchy process (AHP) was applied to quantify the spatiotemporal variations in flood risk in Wuhan during 2000-2018. A comprehensive flood risk assessment index system was constructed from the hazard, sensitivity, and vulnerability components with seven indices. The results showed that the central urban area, especially the area in the west bank of the Yangtze river, had high risk due to its high flood sensitivity that was determined by land use type and high vulnerability with dense population and per unit GDP. Specifically, the Jianghan, Qiaokou, Jiangan, andWuchang districts had the highest flood risk, more than 60% of whose area was in medium or above-medium risk regions. During 2000--2018, the flood risk overall showed an increasing trend, with Hongshan district increasing the most, and the year of 2010 was identified as a turning point for rapid risk increase. In addition, the comparison between the risk maps and actual historical inundation point records showed good agreement, indicating that the assessment framework and method proposed in this study can be useful to assist flood mitigation and management, and relevant policy recommendations were proposed based on the assessment results. [ABSTRACT FROM AUTHOR]

The paper explores the impact of El Niño-Southern Oscillation (ENSO) on rainy season precipitation properties over the Yangtze River Basin. The multi-scale moving t-test was used to determine the onset and withdrawal of the rainy season. Results showed the following: (1) Onset and withdrawal of the averaged rainy season over the Yangtze River Basin showed a similar distribution and both progressed northwards and westwards. There is a trend for delayed onset of rainy season precipitation over the Yangtze River Basin. A similar trend in the withdrawal of rainy season precipitation was not found. (2) The decaying Central and Eastern PacificWarming are indicative of wet signals in the Yangtze River Basin, with precipitation anomalies up to 25% above normal. The decaying Eastern Pacific Cooling and developing Eastern PacificWarming are indicative of dry signals over the Yangtze River Basin, with 5–20% lower than average precipitation (3) ENSO Modoki in the developing phase is more important than the developing ENSO when it comes to present wetter or drier signals. Conversely, the decaying ENSO shows more prominent wet or dry signals than the decaying ENSO Modoki. [ABSTRACT FROM AUTHOR]

This paper discusses the long-term variation in the salinity of the Southern Yellow Sea Cold Water Mass (SYSCWM) and examines factors influencing the SYSCWM based on hydrographic datasets of the China National Standard section and the Korea Oceanographic Data Center. The mean salinity at the center of the SYSCWM showed a decreasing long-term trend. In empirical orthogonal function (EOF) analysis, the second EOF mode showed a similar long-term trend. The mean salinity of the center of the SYSCWM was related to the intrusion of saline water from the Yellow Sea Warm Current (YSWC), the salinity of the source area of the YSWC, the evaporation minus precipitation (E-P) flux, and discharge from the Changjiang River. The decreasing salinity trend to the southwest of Cheju Island produced a freshening trend in the YSWC, resulting in a reduction in the salinity of the SYSCWM. The freshening trends of the water from the northwest Pacific and the South China Sea were seen as the reason for the decreasing salinity trend from the intrusion of water into the Yellow Sea (YS). The freshwater flux influenced the surface salinity and was brought to deep layers by strong mixing in winter. The mean E-P flux signal and Changjiang River discharge signal lagged the first principal component of the SYSCWM by approximately 5 months. [ABSTRACT FROM AUTHOR]

This paper describes a record setting project in the horizontal directional drilling field involving twin pipes with a diameter of 711 mm and a length of 3,300 m. The Yangtze River is the longest river in China. The Jiangdu-Rudong gas pipeline, which is part of the Chinese gas pipeline trunk network, was constructed to transport gas from the north side to the south side of the River. The width of the river surface is 3,000 m, and the length of the crossing is 3,300 m. It was recommended by engineers that twin pipes with a diameter of 711 mm be used instead of the existing pipe with a diameter of 1,016 mm. The required depth of penetration for the crossing was determined by an analysis of 43 years of historical river scour data from 1966 to 2009 combined with a calculated result using a river scour depth formula. The recommended construction scheme included arranging two drilling rigs, laying magnetic-signal submarine cable, using the intersect method, and designing a new flat-barrel combination-type reamer. This major project was finished successfully on July 27, 2013. [ABSTRACT FROM AUTHOR]

Historical distribution characteristics of polycyclic aromatic hydrocarbons (PAHs) and their carriers (i.e., organic matter and mineral particles) in the sediment cores of the Yangtze Estuary were investigated, with emphasis laid on the role of the Yangtze River. Grain size component of sediments (clay, silt, and sand) and organic carbon (black carbon and total organic carbon) in the sediment cores were markedly affected by water flux and sediment discharge of the Yangtze River. Qualitative and quantitative analysis results showed that sands and black carbon acted as the main carriers of PAHs. The sedimentation of two-ring to three-ring PAHs in the estuary had significant correlations with water flux and sediment discharge of the Yangtze River. The relative lower level of the four-ring and five-ring to six-ring PAHs concentrations appeared around the year 2003 and remained for the following several years. This time period accorded well with the water impoundment time of the Three Gorges Reservoir. The decreased level of two-ring to three-ring PAHs occurred in the year 1994, and the peak points around the year 2009 indicated that PAHs sedimentation in the estuary also had close relationship to severe drought and flood in the catchments. The findings presented in this paper could provide references for assessing the impacts of water flux and sediment discharge on the historical deposition of PAHs and their carriers in the Yangtze Estuary. [ABSTRACT FROM AUTHOR]

The Xiaohuangshan site is an early Neolithic settlement in the lower Yangzi River dating to 9000–7000 BP. In this paper, starch grains extracted from the surfaces of 9 pottery sherds and 6 grinding slabs unearthed from the early Xiaohuangshan phase (9000–8500 cal. BP) are identified from Oryza , Triticeae Tribe, Coix lacryma-jobi , Nelumbo sp., Dioscorea opposita Trunb , Vigna and Quercus spp. Based on the statistical analysis of percentage presence and the minimum numbers of plants identified by starch grains on the grinding slabs and potteries, it can be found that rice has become one of the major staple foods together with Triticeae grasses, Job's tears and acorns, which indicates rice should have been cultivated intentionally at Xiaohuangshan. The results also suggest that grinding slabs from Xiaohuangshan were used mainly for processing wild plants other than rice, and plant residues extracted from their surfaces cannot be utilized independently to explore human's subsistence strategies in that time. In addition, acorns probably were cooked whole in the pottery vessels before they were shelled or ground on the grinding slabs in the Xiaohuangshan site. This paper provides new evidence for the beginning of rice cultivation during the early Neolithic in the Lower Yangtze River. [ABSTRACT FROM AUTHOR]

With the advent of acoustic Doppler current profiler (ADCP), the velocity profile method or index velocity method based on a single profile or a fixed-depth cell has been recommended for estimating discharge in tidal reaches. However, in large tidal reaches with a width of nearly 6 km and cross-sectional variability of flow, such as Yangtze Estuary, these methods are not accurate enough for the discharge estimation. Therefore, an improved method named the multiprofile method, is proposed in this paper. The method includes four main steps: (1) calculating the cross-sectional area A with stage data by considering the transverse slope; (2) calculating the depth-mean velocity u at each fixed ADCP; (3) establishing the u − U model with the multiprofile us and estimating the cross-sectional mean velocity U; (4) estimating the final discharge through U multiplied by A. The proposed method was tested at the Xuliujing section of the Yangtze Estuary. The result shows that the multiprofile method averagely improves the accuracy by approximately 5.8% relative to the single-profile method in the discharge estimation, which proves the proposed method to be valid in the discharge estimation of large tidal reach. [ABSTRACT FROM AUTHOR]

The topography is low and flat in the estuarine region of the Yangtze River, where waterlog and salt-affected soil are all through a latent threat to the agricultural development for long time. After the Three-Gorge Project is built up, the Three-Gorge Reservoir adjusts seasonably runoff will impact on the dynamic of soil water and salt in the region. These influence relations are very complicated. Based on the theory of solute transport and the principle of soil water dynamics, the model of soil water and salt transport was created, which involved root water extraction, adsorption-desorption, mobile-immobile region. To overcome numerical dispersion, the paper solved the convection-dispersion equation by Bresler algorithm, the term of time derivative used the approximate difference formula of quadratic differential coefficient based on central difference. Then, the impact of Three-Gorge Project on the regime of soil water and salt in the estuarine region by numerical simulation was studied in. The numerical simulation indicates that electric conductivity of soil one meter thick of each observed section will go down by 0.005-0.174 mS/cm as discharge increases in spring after building the Three-Gorge Reservoir, and up by 0.004-0.416 mS/cm as discharge decreases in autumn-winter. The elementary predicted result of numerical simulation shows that salification will be bigger in autumn than desalinization in spring. The impact degree of the project on the regime of soil salt will be gradually weakened along the river up from the estuary, the nearer to the sea, the bigger the impact, and from cross profiles, the nearer to the river, the bigger the impact. Especially within the range of 4 km of the river, it is more possible that the soil will produce salification or secondary salinization. [ABSTRACT FROM AUTHOR]

The phenomenon of low dissolved oxygen (known as hypoxia) in a coastal ocean system is closely related to a combination of anthropogenic and natural factors. Marine hypoxia occurs in the Yangtze Estuary, China, with high frequency and long persistence. It is related primarily to organic and nutrient enrichment influenced by river discharges and physical factors, such as water mixing. In this paper, a threedimensional hydrodynamic model was coupled to a biological model to simulate and analyze the ecological system of the East China Sea. By comparing with the observation data, the model results can reasonably capture the physical and biochemical dynamics of the Yangtze Estuary. In addition, the sensitive experiments were also used to examine the role of physical forcing (river discharge, wind speed, wind direction) in controlling hypoxia in waters adjacent to the Yangtze Estuary. The results showed that the wind field and river discharge have significant impact on the hypoxia off the Yangtze Estuary. The seasonal cycle of hypoxia was relatively insensitive to synoptic variability in the river discharge, but integrated hypoxic areas were sensitive to the whole magnitude of river discharge. Increasing the river discharge was shown to increase hypoxic areas, while decreasing the river discharge tended to decrease hypoxic areas. The variations of wind speed and direction had a great impact on the integrated hypoxic areas. [ABSTRACT FROM AUTHOR]

Estuary forms a transition zone between inland river and open sea. In China, the estuary of the Yangtze River plays a vital role in connecting the inland and oversea shipping, and witnesses heavy vessel traffic in the recent decades. Nowadays, more attentions have been directed to the issue of ship pollution in busy waterways. In order to investigate the ship emission inventory, this paper presents an Automatic Identification System(AIS) based method. AIS data is the realistic data of vessel traffic including dynamic information (position, speed, course, etc.) and static information (ship type, dimensions, name, etc.). According to ship dimensions, the power of engines is estimated for different ship types. By using AIS based bottom-up approach, ship emission inventories and shares of air pollutants and GHGs (Greenhouse gases) are developed. Spatial distribution of ship emissions is illustrated in the form of heat map. As a case study, the emission inventories are analyzed using AIS data of 2010 in the estuary, and following results are made:(1) shares of the emission are cruise ships 6.59%, bulk carriers 5.16%, container ships 52.96%, tankers 15.16%, fishing ships 9.16%, other ships 10.97%; (2) CO2 is the dominant part of the emission. (3) Areas of highest emission intensity are generally clustered around the South Channel, the North Channel and ports in the vicinity. The proposed method is promising because it is derived from the AIS data which contains not only real data of individual ship but also vessel traffic situation in the study area. It can server as a reference for other researchers and policy makers working in this field. [ABSTRACT FROM AUTHOR]

Recent studies have suggested that large rivers play important roles in mobilizing and transporting black carbon (BC) from land to the ocean. However, the influence of the Changjiang and Huanghe, the two largest rivers in China, on the fate of BC has not been determined. In this paper, we present measurements of BC in both the dissolved and particulate phases in the Changjiang and Huanghe Rivers and in the coastal waters of the East China Sea (ECS). Our results show that dissolved black carbon (DBC) accounted for 3.0 ± 0.4 % and 4.8 ± 3.6 % of the total DOC pool in the Changjiang and Huanghe Rivers and 3.4 ± 0.6 % of the DOC pool in the coast of the ECS. In addition, particulate black carbon (PBC) accounted for 13 ± 0.9 % and 22 ± 11 % of the POC pool in the Changjiang and Huanghe Rivers, respectively. We calculate that the Changjiang and Huanghe transported 4.7 × 10 gC and 1.7 × 10 gC of DBC, and 2.0 × 10 gC and 1.2 × 10 gC of PBC to the ECS and Bohai Sea in 2015. The large amounts of BC transported by the two rivers represent a major sink of anthropogenically derived organic carbon and could have a significant impact on the ecosystem and carbon cycling in China's marginal seas. [ABSTRACT FROM AUTHOR]

The net anthropogenic nitrogen input (NANI) is an important nutrient source that causes eutrophication in water bodies. Understanding the spatio-temporal variation of NANI is important for regional environment assessment and management. This paper calculated NANI in the upper Yangtze River basin (YRB), upstream of the Three Gorges Dam (TGD), from 1990 to 2012, and analyzed its spatio-temporal characteristics. Over the past 23 years of the study, the average annual NANI increased from 3200 kg N km to 4931 kg N km. The major components were fertilizer N application, atmospheric N deposition, and net food and feed N import. In the northwest high mountainous region with a sparse population, the main component was atmospheric N deposition. Fertilizer N application and net food and feed N import were concentrated in the Chengdu Plain because of the high population density and large areas of farmland. This research found that NANI increased with rapid urbanization and increasing population. The Pearson correlation results illustrated that the spatial distributions of NANI and its major components were affected by land cover/use, agricultural GDP and total population. Increasing NANI has been the major cause of the degrading stream water quality over the past 20 years and is becoming a major threat to the water quality of the TGD reservoir. [ABSTRACT FROM AUTHOR]

Water footprint of production can be used to identify pressure on national or regional water resources generated by production activities. Water stress is defined as the ratio of water use (the difference between a regional water footprint of production and a green water footprint) to renewable water resources available in a country or region. Water stress can be used to identify pressure on national or regional water resources generated by production activities. This paper estimates the water footprint of production and the water stress in China during the years 1985-2009. The result shows that China's water footprint of production increased from 781.58 × 109 m3 in 1985 to 1109.76 × 109 m3 in 2009. Mega-cities and regions with less agriculture production due to local climatic conditions (Tibet and Qinghai) had lower water footprint of production, while the provinces (Henan, Shandong) with higher agriculture production had higher footprint. Provinces with severe water stress increased from 6 in 1985 to 9 in 2009. High to severe water stress exists mainly in mega-cities and agricultural areas located in the downstream areas of the Yellow River and the Yangtze River in North and Central China. The outlook for water resources pressure in China is not optimistic, with areas of stress expanding from northern to southern of China. [ABSTRACT FROM AUTHOR]

Recently some generalized autoregressive conditional heteroskedasticity (GARCH) models are proposed and applied to various hydrologic variables to capture and remove the ARCH effect, which has been observed frequently in the residuals from linear autoregressive moving average (ARMA) models fitted to hydrologic time series. As a nonlinear phenomenon of variance behavior, the ARCH effect reveals partially nonstationarity and nonlinearity of hydrological processes. This paper deals with the variation of a river basin using the ARMA-GARCH error model, which combines an ARMA model for modelling the mean behavior and a GARCH model for modelling the variance behavior of the residuals from the ARMA model. Based on the heteroscedasticity of hydrological variable series, the time-varying regional variance is proposed to check the variation of a river basin for the first time. As a study case, the method is applied to four deseasonalized daily discharge series from the middle reach of Yangtze River, China. Through the analyses of the conditional variance in different streamflow series, it is concluded that: (1) The ARCH effect exists in all the studied series which means the stream processes is nonstationary in terms of the variance; (2) The variations of time-varying variances are similar for the series from adjacent hydrological stations, and the similarity degree increases from upstream to downstream; (3) The regional variance is time-varying and can be used for further regional research. [ABSTRACT FROM AUTHOR]

Under the background of vigorously promoting the construction of ecological civilization, the importance of constructing the "non-waste cities" becomes increasingly prominent. Taking 39 cities in the Yangtze River Economic Zone as the research objects, this paper establishes a new evaluation index system for "non-waste cities," and proposes a multi-source, heterogeneous and multi-attribute decision-making method for the comprehensive evaluation of "non-waste cities." Specifically, the evaluation index system of "non-waste cities" is constructed from four aspects: economic level, environmental pollution, resource consumption, and waste utilization. Considering that there is the characteristic of multi-source heterogeneity for the attribute values (that is, real numbers, interval numbers, and fuzzy linguistic variables coexist), the multi-source heterogeneous data are uniformly converted into two-tuples, and then a new two-tuple entropy weight method is proposed to determine the weights of evaluation attributes. Moreover, combining the traditional grey relational analysis method with TOPSIS, a multi-source, heterogeneous and multi-attribute decision-making method based on two-tuple mixed correlation degree (TTMCD-MSHMADM) is proposed to evaluate the "non-waste cities," and an empirical analysis is made for the 39 cities in the Yangtze River Economic Zone. The result gives a theoretical basis for the formulation of sustainable economic development policies in the Yangtze River Economic Zone, and provides a decision reference for selecting the demonstration cities of "non-waste cities." [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to analyze the environmental efficiency level and trend of the transportation sector in the upper–mid–downstream of the Yangtze River Economic Belt and the JingJinJi region in China and assess the effectiveness of policies for protecting the low-carbon environment. Design/methodology/approach: This study uses the meta-frontier slack-based measure (SBM) approach to evaluate environmental efficiency, which targets and classifies specific regions into regional groups. First, this study employs the SBM with the undesirable outputs to construct the environmental efficiency measurement models of the four regions under the meta-frontier and group frontiers, respectively. Then, this study uses the technology gap ratio to evaluate the gap between the group frontier and the meta-frontier. Findings: The analysis reveals several key findings: (1) the JingJinJi region and the downstream of the YEB had achieved the overall optimal production technology in transportation than the other two regions; (2) significant technology gaps in environmental efficiency were observed among these four regions in China; and (3) the downstream region of the YEB exhibited the lowest levels of energy consumption and excessive CO2 emissions. Originality/value: To evaluate the differences in environmental efficiency resulting from regions and technological gaps in transportation, this study employs the meta-frontier model, which overcomes the limitation of traditional environmental efficiency methods. Furthermore, in the practical, the study provides the advantage of observing the disparities in transportation efficiency performed by the Yangtze River Economic Belt and the Beijing–Tianjin–Hebei regions. [ABSTRACT FROM AUTHOR]

Both central-eastern U.S. and China are prone to increasing flooding from Mississippi River and Yangtze River basins respectively. This paper contrasts historical and projected spatialtemporal distribution of extreme precipitation in these two large river basins using 31 CMIP5 (coupled model intercomparison project phase 5) models' historical and RCP8.5 (representative concentration pathway) experiments. Results show that (1) over both river basins, the heaviest rainfall events have increased in recent decades while the lightest precipitation reduced in frequency. Over Mississippi River Basin, both the lightest precipitation (<2.5 mm/day) and heaviest (>50 mm/day) would decrease in frequency notably after mid-2020s while intermediate events occur more frequently in future; whereas over the Yangtze River Basin, all categories of precipitation are projected to increase in frequency over the coming decades. (2) Although the consensus of CMIP5 models was able to reproduce well domain-time mean and even time-averaged spatial distribution of precipitation, they failed to simulate precipitation trends both in spatial distribution and time means. In a similar fashion, models captured well statistics of precipitation but they had difficulty in representing temporal variations of different precipitation intensity categories. (3) The well-documented 2nd half of the 20th century surface summer cooling over the two river basins showed different associations with precipitation trends with higher anti-correlation between them over the U.S. region, implying different processes contributing to the cooling mechanisms of the two river basins. [ABSTRACT FROM AUTHOR]

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]

Excessive nitrogen (N) application has been considered as one of the reasons for restricting yield increases in rice-wheat rotation system in the Yangtze River area. From 2007 to 2009, field experiments were conducted to evaluate the effects of optimized N management on grain yield, nitrogen use efficiency (NUE) and N surplus of winter wheat in Jianghan Plain (Hubei province, China). Results indicated that grain yield and crop N uptake of treatments with reducing fertilizer N (N135(2)for the first year and N120(3)for the second season) did not significantly reduce yield compared to farmers’ practice (FP). Under the same amount of N application, three-time splitting improved grain yield and enhanced NUE as compared with two-time splitting. The optimized N treatment of N135(2)and N120(3)was observed with higher NUE parameters, i.e. recovery efficiency (REN), agronomic efficiency (AEN) and partial factor productivity (PFPN). Positive correlation between SPAD value and leaf N concentration provided the effective tool to evaluate N status during the growth season. The optimized N rate and top dressing frequency could reduce the residual N retained in the 0–20 cm soil layer after harvest, which could reduce the possibility of soil N loss to the environment. This paper provides insights into N management strategy based on farmers’ practices, which could be regarded as a guideline to improve agricultural management for wheat growth season. [ABSTRACT FROM AUTHOR]

Water-induced disasters are harmful and can cause drastic damage. The response to these disasters is critical, and this task continues to gain global attention. A quick and accurate assessment of the damage is vital to mitigate the effects of the water-induced disasters. This paper begins with exploring the S-shaped curve that is widely observed with many types of damage resulting from the various water-induced disasters. Following that, we propose a conceptual model using the grade of a disaster as the crucial factor and recommend a general function in the form of a hyperbolic tangent function. The damage assessment of the flood and drought events that occurred in the Yangtze River Delta was conducted to explain the processes involved in the function configuration. Flood season precipitation and soil moisture were incorporated into the flood and drought models, respectively, to simulate the functions in agricultural areas hit by drought or flood events. Comparing the calculated result and field survey shows the effectiveness of the proposed damaged estimate function. This proposed methodology can be used to quickly assess the flood and drought damage, and it can also be extended to other types of disasters. [ABSTRACT FROM AUTHOR]

Summary: This paper provides the length‐weight and length–length relationships for five fish species in the Zigui section of the lower Three Gorges Reservoir of the Yangtze River. Specimens were collected from December 2014 to January 2017, using various types of fishing gear and electroshock fishing techniques. Length‐weight relationships (LWRs) for one fish species and Length–length relationships (LLRs) for five fish species are unknown to FishBase. New maximum total lengths for four species were also recorded for FishBase. Moreover, standard‐length to total‐length equations for converting size measurements for these five species are presented. [ABSTRACT FROM AUTHOR]

As the large-scale cascaded reservoirs have been developed rapidly in recent years, river basin flood control (RBFC) has become a complex, multi-objective and multi-reservoir problem. In order to realize the optimal operation and management of reservoirs in mainstreams and branches, this paper presents a generalized multi-objective flood control model (MOFCM) for joint optimal dispatching of cascade reservoirs, which is applied to cascade reservoirs in lower reaches of Jinsha River and Three Gorges Reservoir in Yangtze River (JFCR-TGR). Meanwhile, a multi-objective cultural self-adaptive electromagnetism-like mechanism (MOSEM) algorithm is introduced to solve RBFC problem. In the case study, comparing with the natural runoff of the Chuan River, the maximum release of optimal schemes is lesser, its reduced range is from 1727 to 12,887 m/s and the flood peak deduction rate is from 6.4 to 48 %. Results of case studies demonstrate that MOFCM is practicable and efficient for multipurpose multi-reservoir flood control. The optimal operation schemes obtained by MOSEM in JFCR-TGR system can be used to assist the decision makers in choosing the most efficient scheme. Furthermore, MOFCM can accomplish multiple-object optimization effectively under various scheduling situations. [ABSTRACT FROM AUTHOR]

With population growth and economic development, the conflict between supply and demand of water resources is becoming more serious in recent years. In order to alleviate basin water shortage, a novel water resources allocation model which employs large-scale reservoirs to optimize water supply process is proposed in this paper. The proposed model has two conflicting objectives that are the minimization of the total water supply shortfall and the maximization of the total power generation. Because of the huge system scale and numerous constraints, water resources optimal allocation (WROA) is a high dimensional, coupled and nonlinear problem. An improved hybrid optimal method which combines decomposition coordination (DC) and discrete differential dynamic programming (DDDP) is developed to optimize the complex problem. An adaptive bias corridor technology is presented to improve convergence speed during subsystem optimization. Finally, the proposed optimal model and the hybrid method are applied to the water resources allocation in the upper reaches of Yangtze River. The results indicate that the proposed model not only can reduce the total water supply shortfall effectively but also can improve the total power generation. [ABSTRACT FROM AUTHOR]

The Guanyinyan Yangtze River Bridge is the key structure on the second ring highway of Chongqing City, southwest of China. The bridge is a cable-stayed bridge with a main span of 436 m. The main girder is a steel-concrete composite girder with a total width of 36ṡ2 m. The final design solution was based on an extensive comparison of proposals. The main bridge was constructed using the balanced cantilever method. This paper presents the challenges in design and static analysis of the bridge, including the detailed design, global static analysis, local finite element model analysis, the determination of the allowable maximum thickness of steel plate against fatigue and brittle fracture induced by low temperature. [ABSTRACT FROM AUTHOR]

Chinese national fiscal reforms and the transfer of power from the central government to local governments impact the governance of inland waterway transport (IWT). In this paper we argue that the development of IWT on the Yangtze River is strongly influenced by institutional changes at different levels of government in line with the path dependent transformation of the Chinese centrally planned economy. This paper deduces how institutional change of IWT on the Yangtze fails to fulfil its purposes because of institutional legacies and conflicts of interests among the various levels of government and the persistent interwovenness of the state with private enterprises (via SOEs). In order to further stimulate IWT on the Yangtze more institutional changes are on the cards, in particular a need for more (foreign) private involvement and more independent SOEs, but these changes will not necessarily break out of the development path. [ABSTRACT FROM AUTHOR]

The paper presents a three step procedure to allocate flood reserve capacity of the reservoirs in a river basin to manage floods and increase hydropower generation. The first step is trying to identify the flood reserve space and reservoir storage availability during the post-flood season in dry year to evaluate the feasibility for future planned flood reserve capacity. Step 2 is dividing the flood reserve space, by using a novel partitioning method to obtain flood protection coefficient. Step 3 is allocating of flood reserve capacity with various storage options of multi-reservoirs, using a simulation-optimization approach. The results show that the most satisfactory solution both reduces downstream overflow and maximizes hydropower, firm power and target storage rate. [ABSTRACT FROM AUTHOR]

The Inner Lake, a typical waterfront lake located in the middle-lower reaches of the Yangtze River, is selected as the research area in this paper. Through field measurements and laboratory experiments, spatial distribution characteristics of the heavy metal cadmium (Cd) contents were revealed, and the release rate-flow disturbance curve in sediment of the Inner Lake was formed. The mathematical models of the migration and transformation of Cd were built and calibrated. With the models, the fluctuation characteristics of Cd pollution load were quantitatively assessed in different time scales, as in typical years (1998, 2001, and 2004) and in typical tidal cycles of dry seasons and flood seasons. The results showed that: there was a positive correlation between the release rate of Cd and flow disturbance intensity. Influenced by the hydrologic regime of the Yangtze River, the Cd pollution load was higher in high-water years than that in common-water years and low-water years, and was higher in flood seasons than that in dry seasons. Influenced by the tide of the Yangtze River, the Cd pollution load increased during ebb tide and reduced during the rising tide. [ABSTRACT FROM AUTHOR]