Though drought is a recurrent phenomenon in the Jinghe watershed, very little attention has been paid to drought mitigation and preparedness. This article presents a method for the spatial assessment of agricultural d...Though drought is a recurrent phenomenon in the Jinghe watershed, very little attention has been paid to drought mitigation and preparedness. This article presents a method for the spatial assessment of agricultural drought risk in the Jinghe watershed of western China at a 1-km grid scale. A conceptual framework, which emphasizes the combined roles of hazard and vulnerability in defining risk, is used. The Z index method in a GIS environment is used to map the spatial extent of drought hazards. The key social and physical factors that define agricultural drought in the context of the Jinghe watershed are indentified and corresponding thematic maps are prepared. Risk is calculated by the integration of hazard and vulnerability. Results show that the risk gradient follows a north-south and west-east tendency and that agricultural droughts pose the highest risk to northern and northwestern sections of the Jinghe watershed.展开更多
The Andean region of Ecuador is characterized by extreme poverty caused by low agricultural productivity, limited off-farm opportunities, and lack of access to markets. Poverty is related to degradation of natural res...The Andean region of Ecuador is characterized by extreme poverty caused by low agricultural productivity, limited off-farm opportunities, and lack of access to markets. Poverty is related to degradation of natural resources as lagging agricultural productivity leads to incursions into fragile areas and use of erosive farming techniques on steeply sloped hillsides. Food production in fragile areas degrades soil and water resources, contributes to deforestation and loss of biodiversity, and reduces productive potential over time. This article discusses an agricultural development project designed to reduce the long-term downward development spiral in a watershed in Bolivar, Ecuador. The applied research program began with analysis of the state of soil resources, water, and biodiversity in the Chimbo sub-watershed. This information was used to design a plan with the input of local stakeholders to introduce environmentally friendly farming practices, soil and water conservation techniques, and various institutional innovations to promote resource conservation. This adaptive management program has been a solid success. This article describes the project, the challenges it faced, and how the process of adaptive management led to consensus among stakeholders about the appropriateness of sustainable management practices. We show how implementation of enhanced management practices contribute to reduced environmental vulnerability and improved welfare.展开更多
The runoff and runoff process of Eucalyptus plantations natural watershed were studied to provide guidance for scientific evaluation of water conservation capacities of Eucalyptus plantations,compared with the Pinus m...The runoff and runoff process of Eucalyptus plantations natural watershed were studied to provide guidance for scientific evaluation of water conservation capacities of Eucalyptus plantations,compared with the Pinus massoniana forest natural watershed. The runoff volumes of Eucalyptus plantations and P. massoniana forest natural watersheds were continuously monitored using the small watershed runoff monitoring method and the automatic data collection devices from August,2013 to December,2016,and effects of heavy rainfall and continuous rainfall on the runoff process were studied. Results showed that the annual runoff coefficient of Eucalyptus plantations natural watershed was 0. 050,and 55. 4% lower than P. massoniana forest（ 0. 112）,with the difference being significant（ P 〈 0. 01）. Total runoff duration,time of maximum runoff lagging behind rainfall peak,and runoff duration caused by a heavy rainfall process（ amounting to 147. 5 mm） between the two kinds of forest watersheds were significant different,those of Eucalyptus plantations were 35. 6 mm,0. 2 h and 13. 8 h,respectively,while those of P. massoniana forest were28. 5 mm,0. 7 h and 35. 5 h,respectively. Eucalyptus plantations natural watershed produced only 4-days runoff,and runoff depth amounted to3. 8 mm with a 7-days continuous precipitation process of rainfall with 125. 0 mm,while P. massoniana forest natural watershed produced continuously 13-days runoff,and the runoff depth was 10. 1 mm. In conclusion,water conservation capacity of Eucalyptus plantations is obviously lower than P. massoniana forest.展开更多
遵循“基于自然的解决方案(Natural based solution)”理念,本研究开发了由渗滤型边滩、生态跌水和近自然河溪构成的河流多生境自然塑造技术及系统,并在北运河流域的再生水河道台头沟实施了工程应用与示范.结果表明,该技术与系统具有良...遵循“基于自然的解决方案(Natural based solution)”理念,本研究开发了由渗滤型边滩、生态跌水和近自然河溪构成的河流多生境自然塑造技术及系统,并在北运河流域的再生水河道台头沟实施了工程应用与示范.结果表明,该技术与系统具有良好的水质净化效果,对氨氮、总氮、总磷和化学需氧量的平均削减率分别为62.15%、47.46%、48.50%和70.84%;河道修复使得生境质量得到改善,由D级(差)提升至B级(良),生境类型由不足3种提升至超过8种;修复后河道底栖动物的种类数量、BI指数、多样性指数等增加,水鸟从无到有,生物多样性也逐步改善.该技术可为城市特别是城乡结合部小型再生水河道治理提供借鉴.展开更多
The Yangtze River Watershed in China is a climate change hotspot featuring strong spatial and temporal variability;hence, it poses a certain threat to social development. Identifying the characteristics of and regions...The Yangtze River Watershed in China is a climate change hotspot featuring strong spatial and temporal variability;hence, it poses a certain threat to social development. Identifying the characteristics of and regions vulnerable to climate change is significantly important for formulating adaptive countermeasures. However, with regard to the Yangtze River Watershed, there is currently a lack of research on these aspects from the perspective of natural and anthropogenic factors. To address this issue, in this study, based on the temperature and precipitation records from 717 meteorological stations, the RClim Dex and random forest models were used to assess the spatiotemporal characteristics of climate change and identify mainly the natural and anthropogenic factors influencing climate change hotspots in the Yangtze River Watershed for the period 1958-2017. The results indicated a significant increasing trend in temperature, a trend of wet and dry polarization in the annual precipitation, and that the number of temperature indices with significant variations was 2.8 times greater than that of precipitation indices. Significant differences were also noted in the responses of the climate change characteristics of the sub-basins to anthropogenic and natural factors;the delta plain of the Yangtze River estuary exhibited the most significant climate changes, where 88.89% of the extreme climate indices varied considerably. Furthermore, the characteristics that were similar among the identified hotpots, including human activities(higher Gross Domestic Product and construction land proportions) and natural factors(high altitudes and large proportions of grassland and water bodies), were positively correlated with the rapid climate warming.展开更多
基金National Key Technology R&D Program (No. 2008BAK50B05)National Key Project for basic research (973) (No.2009CB421106)the Knowledge Innovation Program of CAS (No. KZCX2-EW-306)
文摘Though drought is a recurrent phenomenon in the Jinghe watershed, very little attention has been paid to drought mitigation and preparedness. This article presents a method for the spatial assessment of agricultural drought risk in the Jinghe watershed of western China at a 1-km grid scale. A conceptual framework, which emphasizes the combined roles of hazard and vulnerability in defining risk, is used. The Z index method in a GIS environment is used to map the spatial extent of drought hazards. The key social and physical factors that define agricultural drought in the context of the Jinghe watershed are indentified and corresponding thematic maps are prepared. Risk is calculated by the integration of hazard and vulnerability. Results show that the risk gradient follows a north-south and west-east tendency and that agricultural droughts pose the highest risk to northern and northwestern sections of the Jinghe watershed.
文摘The Andean region of Ecuador is characterized by extreme poverty caused by low agricultural productivity, limited off-farm opportunities, and lack of access to markets. Poverty is related to degradation of natural resources as lagging agricultural productivity leads to incursions into fragile areas and use of erosive farming techniques on steeply sloped hillsides. Food production in fragile areas degrades soil and water resources, contributes to deforestation and loss of biodiversity, and reduces productive potential over time. This article discusses an agricultural development project designed to reduce the long-term downward development spiral in a watershed in Bolivar, Ecuador. The applied research program began with analysis of the state of soil resources, water, and biodiversity in the Chimbo sub-watershed. This information was used to design a plan with the input of local stakeholders to introduce environmentally friendly farming practices, soil and water conservation techniques, and various institutional innovations to promote resource conservation. This adaptive management program has been a solid success. This article describes the project, the challenges it faced, and how the process of adaptive management led to consensus among stakeholders about the appropriateness of sustainable management practices. We show how implementation of enhanced management practices contribute to reduced environmental vulnerability and improved welfare.
基金Supported by Special Project for Scientific Research of Public Welfare Industry of Ministry of Water Resources(201301044)
文摘The runoff and runoff process of Eucalyptus plantations natural watershed were studied to provide guidance for scientific evaluation of water conservation capacities of Eucalyptus plantations,compared with the Pinus massoniana forest natural watershed. The runoff volumes of Eucalyptus plantations and P. massoniana forest natural watersheds were continuously monitored using the small watershed runoff monitoring method and the automatic data collection devices from August,2013 to December,2016,and effects of heavy rainfall and continuous rainfall on the runoff process were studied. Results showed that the annual runoff coefficient of Eucalyptus plantations natural watershed was 0. 050,and 55. 4% lower than P. massoniana forest（ 0. 112）,with the difference being significant（ P 〈 0. 01）. Total runoff duration,time of maximum runoff lagging behind rainfall peak,and runoff duration caused by a heavy rainfall process（ amounting to 147. 5 mm） between the two kinds of forest watersheds were significant different,those of Eucalyptus plantations were 35. 6 mm,0. 2 h and 13. 8 h,respectively,while those of P. massoniana forest were28. 5 mm,0. 7 h and 35. 5 h,respectively. Eucalyptus plantations natural watershed produced only 4-days runoff,and runoff depth amounted to3. 8 mm with a 7-days continuous precipitation process of rainfall with 125. 0 mm,while P. massoniana forest natural watershed produced continuously 13-days runoff,and the runoff depth was 10. 1 mm. In conclusion,water conservation capacity of Eucalyptus plantations is obviously lower than P. massoniana forest.
文摘遵循“基于自然的解决方案(Natural based solution)”理念,本研究开发了由渗滤型边滩、生态跌水和近自然河溪构成的河流多生境自然塑造技术及系统,并在北运河流域的再生水河道台头沟实施了工程应用与示范.结果表明,该技术与系统具有良好的水质净化效果,对氨氮、总氮、总磷和化学需氧量的平均削减率分别为62.15%、47.46%、48.50%和70.84%;河道修复使得生境质量得到改善,由D级(差)提升至B级(良),生境类型由不足3种提升至超过8种;修复后河道底栖动物的种类数量、BI指数、多样性指数等增加,水鸟从无到有,生物多样性也逐步改善.该技术可为城市特别是城乡结合部小型再生水河道治理提供借鉴.
基金Program for Guangdong Introducing Innovative and Entrepreneurial Teams,No.2019ZT08L213National Natural Science Foundation of China,No.41701631+1 种基金Guangdong Provincial Key Laboratory Project,No.2019B121203011Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou),No.GML2019ZD0403。
文摘The Yangtze River Watershed in China is a climate change hotspot featuring strong spatial and temporal variability;hence, it poses a certain threat to social development. Identifying the characteristics of and regions vulnerable to climate change is significantly important for formulating adaptive countermeasures. However, with regard to the Yangtze River Watershed, there is currently a lack of research on these aspects from the perspective of natural and anthropogenic factors. To address this issue, in this study, based on the temperature and precipitation records from 717 meteorological stations, the RClim Dex and random forest models were used to assess the spatiotemporal characteristics of climate change and identify mainly the natural and anthropogenic factors influencing climate change hotspots in the Yangtze River Watershed for the period 1958-2017. The results indicated a significant increasing trend in temperature, a trend of wet and dry polarization in the annual precipitation, and that the number of temperature indices with significant variations was 2.8 times greater than that of precipitation indices. Significant differences were also noted in the responses of the climate change characteristics of the sub-basins to anthropogenic and natural factors;the delta plain of the Yangtze River estuary exhibited the most significant climate changes, where 88.89% of the extreme climate indices varied considerably. Furthermore, the characteristics that were similar among the identified hotpots, including human activities(higher Gross Domestic Product and construction land proportions) and natural factors(high altitudes and large proportions of grassland and water bodies), were positively correlated with the rapid climate warming.
