According to a lot of hydrological and environmental monitoring data, the condition of soil and water loss in the Lancang River Mekong River watershed (in Yunnan section, China) is described. The occurrence and devel...According to a lot of hydrological and environmental monitoring data, the condition of soil and water loss in the Lancang River Mekong River watershed (in Yunnan section, China) is described. The occurrence and development of soil and water loss is analyzed. The conclusion is that: (1) generally, the situation of soil and water loss in the Lancang River Mekong River watershed (in Yunnan section, China) is light, however, soil and water loss in some regions is serious, especially in the middle reach area of the river; (2) soil and water loss in the Lancang River Mekong River (in Yunnan section, China) watershed presents developing tendency and it is mainly caused by human beings. In accordance with these results, the control measures for soil and water loss are discussed.展开更多
The black soil region of Northeast China is one of the most important food production bases and commodity grain bases in China. However, the continual loss and degradation of precious black soil resources has led to d...The black soil region of Northeast China is one of the most important food production bases and commodity grain bases in China. However, the continual loss and degradation of precious black soil resources has led to direct threats to national food security and regional sustainable development. Therefore, it is necessary to summarize integrated prevention and control experience of small watersheds in black soil region of Northeast China. Tongshuang small watershed, a typical watershed in rolling hills of typical black soil areas in Northeast China, is selected as the study area. Based on nearly 50 years' experience in prevention and control of soil and water loss, the structures and overall benefits of an integrated prevention and control system for soil and water loss are investigated. Then, the 'three defense lines' tri-dimensional protection system with reasonable allocation of different types of soil and water control measures from the hill top to gully is systematically analyzed. The first line on the top hill can weaken and block uphill runoff and sediment, hold water resources and improve soil property. The second line on the hill can truncate slope length, slow down the runoff velocity and reduce erosion energy. The third line in the gully is mainly composed of waterfall engineering, which can inhibit soil erosion and restore land resources. The 'three defense lines' system is feasible for soil and water loss control of small watersheds in the typical black soil region of Northeast China. Through the application of the in Tongshuang small watershed, There are effective improvements in ecological conditions in Tongshuang small watershed after the application of 'three defense lines' soil and water control system. Moreover, the integrated treatment paradigm for soil and water loss in typical black soil region is compared with that in loess region. The results of this study could offer references and experiences for other small watersheds in typical black soil region of Northeast China.展开更多
To investigate the effects of various erosion control measures on mountain floods, a case study was conducted in Censhui River South Branch Watershed using scenario analysis and soil conservation service (SCS) metho...To investigate the effects of various erosion control measures on mountain floods, a case study was conducted in Censhui River South Branch Watershed using scenario analysis and soil conservation service (SCS) methods. A distributed hydrological model was developed, and watershed parameters were determined based on satellite imagery, digital terrain models, digital maps and field investigations. Two types of erosion control measures were investigated: the variation of vegetation covers and the change of cultivation techniques. Seven scenarios were considered for the test watershed. The results show: (1) while the de-vegetation results in the increase of peak discharge, the improve of vegetation covers decreases peak discharge at watershed scale; (2) by both improving vegetation cover and enhancing terrace-cultivation technology, the peak discharge is reduced and the peak flow arrival time is delayed; (3) attention should be attached to both early warning system and measures changing the underlying surface and conveyance systems.展开更多
The capacity of soil and water conservation measures, defined as the maximum quantity of suitable soil and water conservation measures contained in a region, were determined for the Loess Plateau based on zones suitab...The capacity of soil and water conservation measures, defined as the maximum quantity of suitable soil and water conservation measures contained in a region, were determined for the Loess Plateau based on zones suitable for establishing terraced fields, forestland and grassland with the support of geographic information system(GIS) software. The minimum possible soil erosion modulus and actual soil erosion modulus in 2010 were calculated using the revised universal soil loss equation(RUSLE), and the ratio of the minimum possible soil erosion modulus under the capacity of soil and water conservation measures to the actual soil erosion modulus was defined as the soil erosion control degree. The control potential of soil erosion and water loss in the Loess Plateau was studied using this concept. Results showed that the actual soil erosion modulus was 3355 t·km^(–2)·a^(–1), the minimum possible soil erosion modulus was 1921 t·km^(–2)·a^(–1), and the soil erosion control degree was 0.57(medium level) in the Loess Plateau in 2010. In terms of zoning, the control degree was relatively high in the river valley-plain area, soil-rocky mountainous area, and windy-sandy area, but relatively low in the soil-rocky hilly-forested area, hilly-gully area and plateau-gully area. The rate of erosion areas with a soil erosion modulus of less than 1000 t·km^(–2)·a^(–1) increased from 50.48% to 57.71%, forest and grass coverage rose from 56.74% to 69.15%, rate of terraced fields increased from 4.36% to 19.03%, and per capita grain available rose from 418 kg·a^(–1) to 459 kg·a^(–1) under the capacity of soil and water conservation measures compared with actual conditions. These research results are of some guiding significance for soil and water loss control in the Loess Plateau.展开更多
Pisha sandstone is a special kind of soft rock in the semiarid region along the up and middle reaches of Yellow River and Loess Plateau and is severely eroded by wind,rainfall and gravity force.Pisha sandstone region ...Pisha sandstone is a special kind of soft rock in the semiarid region along the up and middle reaches of Yellow River and Loess Plateau and is severely eroded by wind,rainfall and gravity force.Pisha sandstone region is called 'the most severe water loss and soil erosion in the world' and referred to as the 'Earth Cancer' by local residents and experts both at home and abroad.The plan for the control of Pisha sandstone started in the 1950s.Since then a series of projects have been implemented,both engineering and vegetation measures have been developed and widely used to protect Pisha sandstone from erosion.Since seabuckthom was introduced as a viable approach for soil erosion protection and its implementation resulted in a breakthrough to control Loess Plateau,it was considered as an important and efficient measure.Then the seabuckthom flexible dam was proposed for coarse sediment retention and fine sediment deposition.And then a new comprehensive control model using consolidation materials combined with vegetation was proposed and promising results were achieved both in laboratory and field demonstrations.In the future,the complex erosion mechanism and ecological carrying capacity should he studied further and more efficient and practical comprehensive measures shall be developed.Moreover,monitoring systems shall be used to predict and detect the changes in the Pisha sandstone slope and structure.展开更多
Ecological environment issues caused by soil erosion have always been the attractive and significant problems all over the world.Under the background of global warming,debris flow,landslide,and other intense gravitati...Ecological environment issues caused by soil erosion have always been the attractive and significant problems all over the world.Under the background of global warming,debris flow,landslide,and other intense gravitational erosion activities have become aggravated,which leads to the decrease of biological diversity,ecosystem stability,resistance,productivity,and the like,which presents new challenges to traditional measures of soil and water conservation.This article,based on research conducted on controlling mountain hazard on the Xiaojiang River basin over the last 30 years,summarizes the managerial achievement of typical ecological engineering technologies and analyzes the principles and application of each type of treatment.The results indicated that established ecological engineering technologies play a significant role in the prevention and treatment of intense gravitational erosion caused by mountain hazard.However,there are still a great deal of limitation of application condition and maneuverability during management process.How to furtherly develop the rational combining pattern between ecological engineering(e.g.contour hedgerow)and geotechnical engineering(e.g.slit dam)and how to strengthen the risk control and improve management strategy will be the key points for preventing intense gravitational erosion in future by ecological engineering.展开更多
文摘According to a lot of hydrological and environmental monitoring data, the condition of soil and water loss in the Lancang River Mekong River watershed (in Yunnan section, China) is described. The occurrence and development of soil and water loss is analyzed. The conclusion is that: (1) generally, the situation of soil and water loss in the Lancang River Mekong River watershed (in Yunnan section, China) is light, however, soil and water loss in some regions is serious, especially in the middle reach area of the river; (2) soil and water loss in the Lancang River Mekong River (in Yunnan section, China) watershed presents developing tendency and it is mainly caused by human beings. In accordance with these results, the control measures for soil and water loss are discussed.
基金Supported by the National Natural Science Foundation of China,Science Foundation for Youths ( 41001165,40901133,30901163)
文摘The black soil region of Northeast China is one of the most important food production bases and commodity grain bases in China. However, the continual loss and degradation of precious black soil resources has led to direct threats to national food security and regional sustainable development. Therefore, it is necessary to summarize integrated prevention and control experience of small watersheds in black soil region of Northeast China. Tongshuang small watershed, a typical watershed in rolling hills of typical black soil areas in Northeast China, is selected as the study area. Based on nearly 50 years' experience in prevention and control of soil and water loss, the structures and overall benefits of an integrated prevention and control system for soil and water loss are investigated. Then, the 'three defense lines' tri-dimensional protection system with reasonable allocation of different types of soil and water control measures from the hill top to gully is systematically analyzed. The first line on the top hill can weaken and block uphill runoff and sediment, hold water resources and improve soil property. The second line on the hill can truncate slope length, slow down the runoff velocity and reduce erosion energy. The third line in the gully is mainly composed of waterfall engineering, which can inhibit soil erosion and restore land resources. The 'three defense lines' system is feasible for soil and water loss control of small watersheds in the typical black soil region of Northeast China. Through the application of the in Tongshuang small watershed, There are effective improvements in ecological conditions in Tongshuang small watershed after the application of 'three defense lines' soil and water control system. Moreover, the integrated treatment paradigm for soil and water loss in typical black soil region is compared with that in loess region. The results of this study could offer references and experiences for other small watersheds in typical black soil region of Northeast China.
文摘To investigate the effects of various erosion control measures on mountain floods, a case study was conducted in Censhui River South Branch Watershed using scenario analysis and soil conservation service (SCS) methods. A distributed hydrological model was developed, and watershed parameters were determined based on satellite imagery, digital terrain models, digital maps and field investigations. Two types of erosion control measures were investigated: the variation of vegetation covers and the change of cultivation techniques. Seven scenarios were considered for the test watershed. The results show: (1) while the de-vegetation results in the increase of peak discharge, the improve of vegetation covers decreases peak discharge at watershed scale; (2) by both improving vegetation cover and enhancing terrace-cultivation technology, the peak discharge is reduced and the peak flow arrival time is delayed; (3) attention should be attached to both early warning system and measures changing the underlying surface and conveyance systems.
基金National Natural Science Foundation of China,No.41401305,No.41330858The Open Foundation of State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,No.K318009902-14
文摘The capacity of soil and water conservation measures, defined as the maximum quantity of suitable soil and water conservation measures contained in a region, were determined for the Loess Plateau based on zones suitable for establishing terraced fields, forestland and grassland with the support of geographic information system(GIS) software. The minimum possible soil erosion modulus and actual soil erosion modulus in 2010 were calculated using the revised universal soil loss equation(RUSLE), and the ratio of the minimum possible soil erosion modulus under the capacity of soil and water conservation measures to the actual soil erosion modulus was defined as the soil erosion control degree. The control potential of soil erosion and water loss in the Loess Plateau was studied using this concept. Results showed that the actual soil erosion modulus was 3355 t·km^(–2)·a^(–1), the minimum possible soil erosion modulus was 1921 t·km^(–2)·a^(–1), and the soil erosion control degree was 0.57(medium level) in the Loess Plateau in 2010. In terms of zoning, the control degree was relatively high in the river valley-plain area, soil-rocky mountainous area, and windy-sandy area, but relatively low in the soil-rocky hilly-forested area, hilly-gully area and plateau-gully area. The rate of erosion areas with a soil erosion modulus of less than 1000 t·km^(–2)·a^(–1) increased from 50.48% to 57.71%, forest and grass coverage rose from 56.74% to 69.15%, rate of terraced fields increased from 4.36% to 19.03%, and per capita grain available rose from 418 kg·a^(–1) to 459 kg·a^(–1) under the capacity of soil and water conservation measures compared with actual conditions. These research results are of some guiding significance for soil and water loss control in the Loess Plateau.
基金This work is funded by the State Key Research Development Program of China(Grant no.2017YFC0504505)Key Projects of the National Science&Technology Pillar Program(Grant no.2013BAC05B02)Natural Science Foundation of Jiangsu Province(BK20151401).
文摘Pisha sandstone is a special kind of soft rock in the semiarid region along the up and middle reaches of Yellow River and Loess Plateau and is severely eroded by wind,rainfall and gravity force.Pisha sandstone region is called 'the most severe water loss and soil erosion in the world' and referred to as the 'Earth Cancer' by local residents and experts both at home and abroad.The plan for the control of Pisha sandstone started in the 1950s.Since then a series of projects have been implemented,both engineering and vegetation measures have been developed and widely used to protect Pisha sandstone from erosion.Since seabuckthom was introduced as a viable approach for soil erosion protection and its implementation resulted in a breakthrough to control Loess Plateau,it was considered as an important and efficient measure.Then the seabuckthom flexible dam was proposed for coarse sediment retention and fine sediment deposition.And then a new comprehensive control model using consolidation materials combined with vegetation was proposed and promising results were achieved both in laboratory and field demonstrations.In the future,the complex erosion mechanism and ecological carrying capacity should he studied further and more efficient and practical comprehensive measures shall be developed.Moreover,monitoring systems shall be used to predict and detect the changes in the Pisha sandstone slope and structure.
文摘Ecological environment issues caused by soil erosion have always been the attractive and significant problems all over the world.Under the background of global warming,debris flow,landslide,and other intense gravitational erosion activities have become aggravated,which leads to the decrease of biological diversity,ecosystem stability,resistance,productivity,and the like,which presents new challenges to traditional measures of soil and water conservation.This article,based on research conducted on controlling mountain hazard on the Xiaojiang River basin over the last 30 years,summarizes the managerial achievement of typical ecological engineering technologies and analyzes the principles and application of each type of treatment.The results indicated that established ecological engineering technologies play a significant role in the prevention and treatment of intense gravitational erosion caused by mountain hazard.However,there are still a great deal of limitation of application condition and maneuverability during management process.How to furtherly develop the rational combining pattern between ecological engineering(e.g.contour hedgerow)and geotechnical engineering(e.g.slit dam)and how to strengthen the risk control and improve management strategy will be the key points for preventing intense gravitational erosion in future by ecological engineering.