Huaihe River is one of three major rivers in China with a large population and developed economy. By the 1970s, the water quality of Huaihe River was deteriorating daily and more than a hundred serious pollution accid...Huaihe River is one of three major rivers in China with a large population and developed economy. By the 1970s, the water quality of Huaihe River was deteriorating daily and more than a hundred serious pollution accidents of water quality happened and caused the inestimable losses in the production, life and health of residents along the river and terribly damaged the ecological system of the river. Through the continuous large-scale treatment for more than 10 years, the deterioration of water quality in Huaihe River has been basically inhibited. Nevertheless, the water pollution in Huaihe River is, on the whole, still very serious for many reasons, including special climatic conditions, terrible lack of water resource, obsolete industrial structure and unsound management system for the river, etc. This essay deeply analyzes the rea- sons why the water pollution of Huaihe River is "chronic" and puts forward the corresponding countermeasures for how to continuously improve the water quality of the river. In the end, this essay argues that it still takes 30-50 years or even a longer period, even if every measures are implemented smoothly and strictly, to actually make the water of Huaihe River clean and gradually restore its normal ecological and environmental functions.展开更多
The current environmental flow assessment of Chinese rivers is thought to have three shortcomings: The first is that environmental flow requirements of reservoirs in dammed rivers are usually not explicitly considered...The current environmental flow assessment of Chinese rivers is thought to have three shortcomings: The first is that environmental flow requirements of reservoirs in dammed rivers are usually not explicitly considered; the second is that enough attentions have not been paid to the inherent links between flow regime and ecological processes; the third is that most studies focus on the variable range of merely one hydrological element such as discharge needed by riverine ecosystems. Here, first proposed is a holistic method for environmental flow assessment, the flow-ecological response relationship method that is suitable for large rivers with relatively abundant ecological data. Based on the conceptual models and quantitative relationships between flow and ecological response, this method comprehensively considers the ecological conservation requirements of both reservoir and its downstream reach. Then, it is applied to assessing the environmental flows of the Three Gorges Reservoir and its downstream reach by the following steps: 1) Construction of conceptual models of flow-ecological response; 2) identification of ecological targets of environmental flows and their key periods; 3) development of the quantitative relationships between hydrological indicators and ecological indictors; 4) preliminary assessment of environmental flow according to the tradeoff between ecological targets and water demands of human. The environmental flow hydrographs obtained have explicit ecological conservation targets, time schedule of achieving each target, and characteristics of multiple hydrological elements such as flow, water level, frequency, timing, duration and rate of change. The case study has tested the reasonability and feasibility of this method, and the results of this study are expected to provide technical support and decision reference for improving the operation of the Three Gorges-Gezhouba cascade reservoirs.展开更多
文摘Huaihe River is one of three major rivers in China with a large population and developed economy. By the 1970s, the water quality of Huaihe River was deteriorating daily and more than a hundred serious pollution accidents of water quality happened and caused the inestimable losses in the production, life and health of residents along the river and terribly damaged the ecological system of the river. Through the continuous large-scale treatment for more than 10 years, the deterioration of water quality in Huaihe River has been basically inhibited. Nevertheless, the water pollution in Huaihe River is, on the whole, still very serious for many reasons, including special climatic conditions, terrible lack of water resource, obsolete industrial structure and unsound management system for the river, etc. This essay deeply analyzes the rea- sons why the water pollution of Huaihe River is "chronic" and puts forward the corresponding countermeasures for how to continuously improve the water quality of the river. In the end, this essay argues that it still takes 30-50 years or even a longer period, even if every measures are implemented smoothly and strictly, to actually make the water of Huaihe River clean and gradually restore its normal ecological and environmental functions.
基金supported by the Ministry of Science and Technology of China (Grant Nos. 2012BAC06B01, 2012BAC06B04)
文摘The current environmental flow assessment of Chinese rivers is thought to have three shortcomings: The first is that environmental flow requirements of reservoirs in dammed rivers are usually not explicitly considered; the second is that enough attentions have not been paid to the inherent links between flow regime and ecological processes; the third is that most studies focus on the variable range of merely one hydrological element such as discharge needed by riverine ecosystems. Here, first proposed is a holistic method for environmental flow assessment, the flow-ecological response relationship method that is suitable for large rivers with relatively abundant ecological data. Based on the conceptual models and quantitative relationships between flow and ecological response, this method comprehensively considers the ecological conservation requirements of both reservoir and its downstream reach. Then, it is applied to assessing the environmental flows of the Three Gorges Reservoir and its downstream reach by the following steps: 1) Construction of conceptual models of flow-ecological response; 2) identification of ecological targets of environmental flows and their key periods; 3) development of the quantitative relationships between hydrological indicators and ecological indictors; 4) preliminary assessment of environmental flow according to the tradeoff between ecological targets and water demands of human. The environmental flow hydrographs obtained have explicit ecological conservation targets, time schedule of achieving each target, and characteristics of multiple hydrological elements such as flow, water level, frequency, timing, duration and rate of change. The case study has tested the reasonability and feasibility of this method, and the results of this study are expected to provide technical support and decision reference for improving the operation of the Three Gorges-Gezhouba cascade reservoirs.