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Main issues in research and practice of environmental protection for water conservancy and hydropower projects in China 被引量:6
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作者 Ang Chen Miao Wu +3 位作者 Kai-qi Chen Zhi-yu Sun Chen Shen Peng-yuan Wang 《Water Science and Engineering》 EI CAS CSCD 2016年第4期312-323,共12页
In this paper,we generally summarize the main issues in the operational period of water conservancy and hydropower projects in China over the past several decades.First,the adverse impacts of these projects since the ... In this paper,we generally summarize the main issues in the operational period of water conservancy and hydropower projects in China over the past several decades.First,the adverse impacts of these projects since the technical guidelines were proposed in 2006 are analyzed.Then,combined with projects and experience from 2006 to 2014,the four main issues are summarized:(1) There exist many questions in the design and construction of fishways,which are useful for fish migration,and the migration effects are not as expected.(2) Temperature stratification affecting the downstream fish is the major impact of temperature,and alters fish spawning in the reproduction season.(3)Ecological base flow has been one of the primary questions of the last 30 years in China,the greatest related difficulty being quantification of the amount and flow process necessary to satisfy fish life history.(4) Fish habitat protection and restoration are popular topics in recent years with the development of river ecosystem restoration.Fish habitat loss due to the impacts of dam construction and habitat fragmentation has become more and more serious.These four issues are now the main difficulties in water project management,and interact with one another to bear combined effects on river ecosystems.The issues of eco-hydraulic consideration in the design period are the key factors.Finally,future priorities for research and practice of environmental protection for water conservancy and hydropower projects in China are proposed.The main purpose of this paper is to enhance the scientific research,monitoring,and assessment of operating effectiveness. 展开更多
关键词 Temperature STRATIFICATION ECOLOGICAL base flow FISH HABITAT Environmental protection
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Water Quality Model Establishment for Middle and Lower Reaches of Hanshui River,China 被引量:3
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作者 WANG Qinggai ZHAO Xiaohong +3 位作者 YANG Mushui ZHAO Yue LIU Kun MA Qiang 《Chinese Geographical Science》 SCIE CSCD 2011年第6期646-655,共10页
With the development of industry and agriculture,nitrogen,phosphorus and other nutrients in the Hanshui River greatly increase and eutrophication has become an important threat to the water quality of the Hanshui Rive... With the development of industry and agriculture,nitrogen,phosphorus and other nutrients in the Hanshui River greatly increase and eutrophication has become an important threat to the water quality of the Hanshui River,especially in the middle and lower reaches.The primary objective of this study was to establish the water quality model for the middle and lower reaches of the Hanshui River based on the model of MIKE 11.The main pollutants migration and transformation process could be simulated using the water quality model.The rainfall-runoff model,hy-drodynamic model and water quality model were established using MIKE 11.The pollutants,such as chemical oxygen demand(COD),biochemical oxygen demand(BOD),ammonia nitrogen,nitrate nitrogen,phosphorus,dissolved oxy-gen(DO),were simulated and predicted using the above three models.A set of methods computing non-point source pollution load of the Hanshui River Basin was proposed in this study.The simulated and observed values of COD,BOD5,ammonia,nitrate,DO,and total phosphorus were compared after the parameter calibration of the water quality model.The simulated and observed results match better,thus the model can be used to predict water quality in the fu-ture for the Hanshui River.The pollution trend could be predicted using the water quality model according pollution load generation.It is helpful for government to take effective measures to prevent the water bloom and protect water quality in the river. 展开更多
关键词 rainfall-runoff model hydrodynamic model water quality model Hanshui River MIKE 11
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Bridging gaps between environmental flows theory and practices in China 被引量:1
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作者 Ang Chen Miao Wu +7 位作者 Sai-nan Wu Xin Sui Jing-ya Wen Peng-yuan Wang Lin Cheng Guy R.Lanza Chun-na Liu Wan-lin Jia 《Water Science and Engineering》 EI CAS CSCD 2019年第4期284-292,共9页
In recent decades,a series of policies and practices for environmental flows(e-flows)have been implemented in China,with the sustainable development goal of balancing the utilization and protection of water resources ... In recent decades,a series of policies and practices for environmental flows(e-flows)have been implemented in China,with the sustainable development goal of balancing the utilization and protection of water resources among social,economic,and ecological needs.The aims of this study were to determine the main challenges and issues in e-flows implementation at different scales by analyzing policies and practices for eflows in China,and to propose some recommendations for bridging the gaps between the science and implementation of e-flows.The gaps between the science and implementation of e-flows were found after review of literature,policies,and practices,and it was found that ecological flow was a more widely used term by the government,rather than e-flows,in implementation.The plans and effects of e-flows implementation are discussed in this paper and challenges of e-flows implementation are recognized:(1)limited water resources and uneven spatial and temporal distribution,(2)a weak scientific basis for e-flows implementation,(3)poor operability of e-flows science,and(4)ineffective supervision and guarantee measures.The recommendations are(1)to strengthen the scientific foundation of e-flows,(2)to improve effectiveness in application of e-flows science,and(3)to propose operable and effective supervision and guarantee measures.This paper elaborates the current understanding of e-flows science and provides practical recommendations for implementing e-flows and for improving the effectiveness in e-flows implementation.To bridge the gaps between science and implementation of e-flows and improve the operability of policies in future practices,more scientific research on practices is recommended through adaptive management. 展开更多
关键词 Environmental flows Ecological flow Integrated water resources management Adaptive management Sustainable development
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Soil Nutrient Distribution in Two Typical Paddy Terrace Wetlands Along an Elevation Gradient During the Fallow Period 被引量:2
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作者 WANG Qinggai BAI Junhong +3 位作者 HUANG Laibin DENG Wei XIAO Rong ZHANG Kejiang 《Journal of Mountain Science》 SCIE CSCD 2011年第3期476-483,共8页
Soil nutrient concentrations in the top soils from two paddy terraces were determined in order to investigate spatial distributions of soil nutrients along the elevations on the Yunnan plateau of China during the fall... Soil nutrient concentrations in the top soils from two paddy terraces were determined in order to investigate spatial distributions of soil nutrients along the elevations on the Yunnan plateau of China during the fallow period.Results showed that soil nutrients in both terraces were higher than the reference concentrations except for SOC,TN,TP and Fe.Soil macronutrients didn't show significant differences in both terraces except for Mg and Ca,so did soil micronutrients except for Mn.Spatial distribution patterns of soil nutrients along the increasing elevations were different in both terraces.However,soil nutrients in both terraces were generally not significantly influenced by the elevations and soil pH values.The findings of this study can contribute to soil fertility management and ecological protection of Hani terraces. 展开更多
关键词 Spatial distribution MACRONUTRIENTS MICRONUTRIENTS Hani terrace Elevations
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Identification and spatial pattern analysis of alpine timberline by remote sensing methods in Yarlung Zangpo Grand Canyon 被引量:1
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作者 ZHU Bei WANG Shi-yan +6 位作者 SU Wei CHEN Kai-qi LIU Chang DU Yan-liang WANG Liang HAN Zhen ZOU Jiang-xiang 《Journal of Mountain Science》 SCIE CSCD 2021年第9期2304-2314,共11页
As an important ecotone,the alpine timberline is the boundary between closed-canopy montane forest and alpine vegetation,and is highly sensitive to global and regional climate changes.We provided a way to identify and... As an important ecotone,the alpine timberline is the boundary between closed-canopy montane forest and alpine vegetation,and is highly sensitive to global and regional climate changes.We provided a way to identify and extract the alpine timberline in Yarlung Zangpo Grand Canyon Nature Reserve by using remote sensing data and spatial analysis based on land use/land cover classification and NDVI distribution characteristics.Combining DEM data,the influence of slope and aspect on the distribution of alpine timberline was explored.The results showed that the alpine timberline in Yarlung Zangpo Grand Canyon is transitional timberline,with the upper boundary approximately distributed at the elevation of 3422-4373 m,the lower boundary at approximately 3270-4164 m,with a width of about 110-280 m.Alpine timberline was mainly distributed on steep and very steep slopes ranging from 25°to 45°.The maximum elevation of both the upper and lower boundaries occurred on steep slopes.The distribution of alpine timberline varies with aspects,with sunny slopes having a higher boundary than shady slopes. 展开更多
关键词 Alpine timberline ASPECT Normalized Difference Vegetation Index Remote sensing classification SLOPE
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Sensitivity Analysis of Thermal Equilibrium Parameters of MIKE 11 Model:A Case Study of Wuxikou Reservoir in Jiangxi Province of China 被引量:1
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作者 WANG Qinggai ZHAO Xiaohong +2 位作者 CHEN Kaiqi LIANG Peng LI Shibei 《Chinese Geographical Science》 SCIE CSCD 2013年第5期584-593,共10页
Sensitivity analysis of thermal equilibrium parameters in the reservoir module of MIKE 11 model was conducted for the Wuxikou Reservoir in Jiangxi Province of China in order to apply the module to the environmental im... Sensitivity analysis of thermal equilibrium parameters in the reservoir module of MIKE 11 model was conducted for the Wuxikou Reservoir in Jiangxi Province of China in order to apply the module to the environmental impact assessment to accurately predict water temperature of reservoirs.Results showed that radiation parameter A and evaporation-first parameter were much more sensitive than other parameters.The values of the radiation parameter A ranged from 0.10 to 0.34.The values of evaporation-first parameter varied from 0 to 10.The sensitivity of solar absorption parameters was less than that of evaporation parameter,of which light attenuation values ranged from 0.5 to 0.7,and this parameter would not impact model results if it was more than 2.Constants in Beer's law ranged from 0.2 to 0.7.Radiation parameter B was not more sensitive than evaporation parameter and its reasonable range was higher than 0.48.The fitting curves showed consistent changing tendency for these parameters within the reasonable ranges.Additionally,all the thermal equilibrium parameters had much more important effects on surface water temperature than deep water temperature.Moreover,if no observed data could be obtained,the local empirical value would be used to input to the MIKE 11 model to simulate the changes in the discharged outflow-water temperature qualitatively. 展开更多
关键词 MIKE 11 model thermal equilibrium parameters discharged outflow-water temperature sensitivity analysis temperature difference
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Dynamics of Microbial Activity Related to N Cycling in Cd-Contaminated Soil During Growth of Soybean 被引量:1
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作者 YANG Ye CHEN Ying-Xu +1 位作者 TIAN Guang-Ming ZHANG Zi-Jian 《Pedosphere》 SCIE CAS CSCD 2007年第3期383-388,共6页
The potential influences of cadmium (Cd) on the biochemical processes of the soil nitrogen (N) cycle, along with the dynamics of ammonification, nitrification, and denitrification processes in the rhizosphere and non-... The potential influences of cadmium (Cd) on the biochemical processes of the soil nitrogen (N) cycle, along with the dynamics of ammonification, nitrification, and denitrification processes in the rhizosphere and non-rhizosphere (bulk soil), respectively, were investigated in a Cd-stressed system during an entire soybean growing season. In terms of Cd pollution at the seedling stage, the ammonifying bacteria proved to be the most sensitive microorganisms, whereas the effects of Cd on denitrification were not obvious. Following the growth of soybeans, the influences of Cd on ammonification in the bulk soil were: toxic impacts at the seedling stage, stimulatory effects during the early flowering stage, and adaptation to the pollutant during the podding and ripening stages. Although nitrification and denitrification in the bulk soil decreased throughout the entire growth cycle, positive adaptation to Cd stress was observed during the ripening stage. Moreover, during the ripening stage, denitrification in the bulk soil under high Cd treatment (20 mg kg-1) was even higher than that in the control, indicating a probable change in the ecology of the denitrifying microbes in the Cd-stressed system. Changes in the activity of microbes in the rhizosphere following plant growth were similar to those in the non-rhizosphere in Cd treatments; however, the tendency of change in the rhizosphere seemed to be more moderate. This suggested that there was some mitigation of Cd stress in the rhizosphere. 展开更多
关键词 CADMIUM microbial activity nitrogen cycle RHIZOSPHERE
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Analyzing and forecasting CO2 emission reduction in China's steel industry
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作者 Chengkang GAO Dan WANG +2 位作者 Baohua ZHAO Shan CHEN Wei QIN 《Frontiers of Earth Science》 SCIE CAS CSCD 2015年第1期105-113,共9页
Recent measures of carbon dioxide emissions from the steel industry of China have indicated a high rate of total CO2 emissions from the industry, even compared to the rest of the world. So, CO2 emission reduction in C... Recent measures of carbon dioxide emissions from the steel industry of China have indicated a high rate of total CO2 emissions from the industry, even compared to the rest of the world. So, CO2 emission reduction in China's steel industry was analyzed, coupling the whole process and scenarios analysis. First, assuming that all available advanced technologies are almost adopted, this study puts forward some key potential-sectors and explores an optimal technical route for reducing CO2 emissions from the Chinese steel industry based on whole process analysis. The results show that in the stages of coking, sintering, and iron making, greater potential for reducing emissions would be fulfilled by taking some technological measures. If only would above well-developed technolo- gies be fulfill, the CO2 emissions from 5 industry production stages would be reduced substantially, and CO2 emissions per ton of steel could be decreased to 1.24 (ton/ton-steel) by 2020. At the same time, the scenarios analysis indicates that if mature carbon-reducing technol- ogies are adopted, and if the difference between steel output growth rate and the GDP growth rate could be controlled below 3%, CO2 emissions from China's steel industry would approach the goal of reducing CO2 emissions per GDP unit by 40%-45% of the 2005 level by 2020. This indicates that the focus of carbon dioxide emissions reduction in China lies in policy adjustments in order to enhance technological application, and lies in reasonably controlling the pace of growth of GDP and steel output. 展开更多
关键词 CO2 emission whole-process scenario analysis Chinese steel industry ecological industry
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Geospatial data ontology:the semantic foundation of geospatial data integration and sharing 被引量:6
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作者 Kai Sun Yunqiang Zhu +4 位作者 Peng Pan Zhiwei Hou Dongxu Wang Weirong Li Jia Song 《Big Earth Data》 EI 2019年第3期269-296,共28页
Effective integration and wide sharing of geospatial data is an important and basic premise to facilitate the research and applications of geographic information science.However,the semantic heterogeneity of geospatia... Effective integration and wide sharing of geospatial data is an important and basic premise to facilitate the research and applications of geographic information science.However,the semantic heterogeneity of geospatial data is a major problem that significantly hinders geospatial data integration and sharing.Ontologies are regarded as a promising way to solve semantic problems by providing a formalized representation of geographic entities and relationships between them in a manner understandable to machines.Thus,many efforts have been made to explore ontology-based geospatial data integration and sharing.However,there is a lack of a specialized ontology that would provide a unified description for geospatial data.In this paper,with a focus on the characteristics of geospatial data,we propose a unified framework for geospatial data ontology,denoted GeoDataOnt,to establish a semantic foundation for geospatial data integration and sharing.First,we provide a characteristics hierarchy of geospatial data.Next,we analyze the semantic problems for each characteristic of geospatial data.Subsequently,we propose the general framework of GeoDataOnt,targeting these problems according to the characteristics of geospatial data.GeoDataOnt is then divided into multiple modules,and we show a detailed design and implementation for each module.Key limitations and challenges of GeoDataOnt are identified,and broad applications of GeoDataOnt are discussed. 展开更多
关键词 Geospatial data ONTOLOGY geospatial semantics semantic heterogeneity data integration data sharing
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Development of a model-based flood emergency management system in Yujiang River Basin, South China
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作者 Yong ZENG Yanpeng CAI +1 位作者 Peng JIA Jiansu MAO 《Frontiers of Earth Science》 SCIE CAS CSCD 2014年第2期231-241,共11页
Flooding is the most frequent disaster in China. It affects people's lives and properties, causing considerable economic loss. Flood forecast and operation of reservoirs are important in flood emergency management. A... Flooding is the most frequent disaster in China. It affects people's lives and properties, causing considerable economic loss. Flood forecast and operation of reservoirs are important in flood emergency management. Although great progress has been achieved in flood forecast and reservoir operation through using computer, network technology, and geographic information system technology in China, the prediction accuracy of models are not satisfactory due to the unavailability of real-time monitoring data. Also, real-time flood control scenario analysis is not effective in many regions and can seldom provide online decision support function. In this research, a decision support system for real-time flood forecasting in Yujiang River Basin, South China (DSS-YRB) is introduced in this paper. This system is based on hydrological and hydraulic mathematical models. The conceptual framework and detailed components of the proposed DSS-YRB is illustrated, which employs real-time rainfall data conversion, model-driven hydrologic forecasting, model calibration, data assimilation methods, and reservoir operational scenario analysis. Multi-tiered architecture offers great flexibility, portability, reusability, and relia- bility. The applied case study results show the development and application of a decision support system for realtime flood forecasting and operation is beneficial for flood control. 展开更多
关键词 FLOOD decision support system NUMERICALMODELING scenarios analysis Yujiang River Basin
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