In the research, problems and damages of soil erosions in West -East Natural Gas Transmission were analyzed; the reasons were summarized and the characteristics of soil erosion were researched in order to explore prin...In the research, problems and damages of soil erosions in West -East Natural Gas Transmission were analyzed; the reasons were summarized and the characteristics of soil erosion were researched in order to explore principles of pipeline prevention and seek countermeasures.展开更多
In the design,construction and operation periods of the Three Gorges Project (TGP),great challenges have been met in different fields such as water resources and hydropower project construction,electromechanical equip...In the design,construction and operation periods of the Three Gorges Project (TGP),great challenges have been met in different fields such as water resources and hydropower project construction,electromechanical equipment manufacture and ecological environment protection.In view of the key techniques and difficulties in the construction period,scientific and technological breakthroughs have been made by the experts and scholars of various fields and a series of innovative achievements are gained,which make the scientific and technological levels in relevant fields improved.Some major innovative achievements in the construction and operation of TGP are enumerated,which are significant for the hydropower project construction and clean energy development in the future in China.展开更多
Seeking water and earning their livelihoods is the natural selection of human beings.Like other rivers on the earth,the Yangtze River is the birthplace of human civilization and survival.As an ecosystem,the Yangtze Ri...Seeking water and earning their livelihoods is the natural selection of human beings.Like other rivers on the earth,the Yangtze River is the birthplace of human civilization and survival.As an ecosystem,the Yangtze River Basin is evolving under the influences of natural factors and human activities.Because of soil erosion,pollution and human activities,the imbalance of secondary environment is exacerbated and the ecological environment has become more vulnerable,so it is urgent to mitigate and prevent the ecological crisis.The practice has proved that implementation of engineering measures is an effective way to improve the ecological environment.The Three Gorges Project (TGP) has a flood control storage capacity of 22.15 billion m 3,effectively storing the flood water upstream of Yichang,and protects 15 million people and 1.5 million hm 2 farmland.Furthermore,the project can prevent or slow down the sedimentation and shrinkage of the lakes in the middle Yangtze River such as Dongting Lake;with an average annual power generation of about 90 billion kW· h,it can significantly reduce the emissions of harmful gas like CO 2.In general,the construction of TGP is conducive to the ecological and environmental protection in the Yangtze River Basin and China,even the world.展开更多
The Conversion of Farmland to Forests Project (CFF) is one of the six great forest ecological Projects inChina and one of the ten great forest ecological Projects in the world, ranking the third in overall scale and t...The Conversion of Farmland to Forests Project (CFF) is one of the six great forest ecological Projects inChina and one of the ten great forest ecological Projects in the world, ranking the third in overall scale and the first ininvestment. CFF was officially initiated in 2002, covering 1897 counties (county-level cities and districts) in 25provinces (autonomous regions or municipalities) of China. The whole investment is more than 40 billion US$ duringabout 20 years (from 1999 to 2017), aiming to form better ecology system in fragile ecology regions and effectivelycontrol the soil and water erosion of the Yangtze and the Yellow River and sandstorm of the Three-north Regions inChina. The experimental Project of CFF began in 1999, including Sichuan, Shanxi and Gansu province, and the scopeof CFF was widened later. About 1.16 million ha of farmlands were converted to forestlands, and one million ha ofplantation in mountains and wasted lands were completed in 3 years, involving 20 provinces (autonomous regions andmunicipalities), 400 counties, 27 thousand villages, 5.7 thousand towns, 4.1 million farm families and 16 millionfarmers.展开更多
Aims Ecosystem engineers substantially modify the environment via their impact on abiotic conditions and the biota,resulting in facilitation of associated species that would not otherwise grow.Yet,reciprocal effects a...Aims Ecosystem engineers substantially modify the environment via their impact on abiotic conditions and the biota,resulting in facilitation of associated species that would not otherwise grow.Yet,reciprocal effects are poorly understood as studies of plant–plant interactions usually estimate only benefits for associated species,while how another trophic level may mediate direct and indirect feedback effects for ecosystem engineers is hardly considered.Methods We ran a field experiment with two ecosystem engineers(Arenaria tetraquetra and Hormathophylla spinosa)blooming either alone or with associated plants to decompose net effects and to test the hypothesis that pollinator-mediated interactions provide benefits that balance costs of facilitation by ecosystem engineers.Important Findings We found that net costs of facilitation are accompanied by pollinator-mediated benefits.Despite ecosystem engineers producing fewer flowers per plant,they were visited by more and more diverse pollinators per flower when blooming with associated plants than when blooming alone.Although seed production per plant was higher when ecosystem engineers bloomed alone,fruit set and seed set varied between species.In one case(A.tetraquetra),fruit and seed sets were negatively affected by the presence of associated plants,whereas,in another case(H.spinosa),fruit set and seed set were higher and unaffected when ecosystem engineers bloomed with associated plants,respectively.Our findings suggest that besides experiencing direct costs,ecosystem engineers can also benefit from facilitating other species via increasing their own visibility to pollinators.Thus,we highlight that pollination interactions can compensate for costs of facilitation depending on ecosystem engineer species.This study illuminates how the outcome of direct plant–plant interactions might be mediated by indirect interactions including third players.展开更多
基金Supported by Scientific Research Program of Water Resources Department of the Xinjiang Uygur Autonomous Region (xjsl-2011-11)Young Core Project of Northwest A&F University (KZCXI-10-4-1)~~
文摘In the research, problems and damages of soil erosions in West -East Natural Gas Transmission were analyzed; the reasons were summarized and the characteristics of soil erosion were researched in order to explore principles of pipeline prevention and seek countermeasures.
文摘In the design,construction and operation periods of the Three Gorges Project (TGP),great challenges have been met in different fields such as water resources and hydropower project construction,electromechanical equipment manufacture and ecological environment protection.In view of the key techniques and difficulties in the construction period,scientific and technological breakthroughs have been made by the experts and scholars of various fields and a series of innovative achievements are gained,which make the scientific and technological levels in relevant fields improved.Some major innovative achievements in the construction and operation of TGP are enumerated,which are significant for the hydropower project construction and clean energy development in the future in China.
文摘Seeking water and earning their livelihoods is the natural selection of human beings.Like other rivers on the earth,the Yangtze River is the birthplace of human civilization and survival.As an ecosystem,the Yangtze River Basin is evolving under the influences of natural factors and human activities.Because of soil erosion,pollution and human activities,the imbalance of secondary environment is exacerbated and the ecological environment has become more vulnerable,so it is urgent to mitigate and prevent the ecological crisis.The practice has proved that implementation of engineering measures is an effective way to improve the ecological environment.The Three Gorges Project (TGP) has a flood control storage capacity of 22.15 billion m 3,effectively storing the flood water upstream of Yichang,and protects 15 million people and 1.5 million hm 2 farmland.Furthermore,the project can prevent or slow down the sedimentation and shrinkage of the lakes in the middle Yangtze River such as Dongting Lake;with an average annual power generation of about 90 billion kW· h,it can significantly reduce the emissions of harmful gas like CO 2.In general,the construction of TGP is conducive to the ecological and environmental protection in the Yangtze River Basin and China,even the world.
文摘The Conversion of Farmland to Forests Project (CFF) is one of the six great forest ecological Projects inChina and one of the ten great forest ecological Projects in the world, ranking the third in overall scale and the first ininvestment. CFF was officially initiated in 2002, covering 1897 counties (county-level cities and districts) in 25provinces (autonomous regions or municipalities) of China. The whole investment is more than 40 billion US$ duringabout 20 years (from 1999 to 2017), aiming to form better ecology system in fragile ecology regions and effectivelycontrol the soil and water erosion of the Yangtze and the Yellow River and sandstorm of the Three-north Regions inChina. The experimental Project of CFF began in 1999, including Sichuan, Shanxi and Gansu province, and the scopeof CFF was widened later. About 1.16 million ha of farmlands were converted to forestlands, and one million ha ofplantation in mountains and wasted lands were completed in 3 years, involving 20 provinces (autonomous regions andmunicipalities), 400 counties, 27 thousand villages, 5.7 thousand towns, 4.1 million farm families and 16 millionfarmers.
基金supported by the Swiss National Science Foundation[grant numbers 148261,170645 and 180195]by the ETH Biocommunication group.
文摘Aims Ecosystem engineers substantially modify the environment via their impact on abiotic conditions and the biota,resulting in facilitation of associated species that would not otherwise grow.Yet,reciprocal effects are poorly understood as studies of plant–plant interactions usually estimate only benefits for associated species,while how another trophic level may mediate direct and indirect feedback effects for ecosystem engineers is hardly considered.Methods We ran a field experiment with two ecosystem engineers(Arenaria tetraquetra and Hormathophylla spinosa)blooming either alone or with associated plants to decompose net effects and to test the hypothesis that pollinator-mediated interactions provide benefits that balance costs of facilitation by ecosystem engineers.Important Findings We found that net costs of facilitation are accompanied by pollinator-mediated benefits.Despite ecosystem engineers producing fewer flowers per plant,they were visited by more and more diverse pollinators per flower when blooming with associated plants than when blooming alone.Although seed production per plant was higher when ecosystem engineers bloomed alone,fruit set and seed set varied between species.In one case(A.tetraquetra),fruit and seed sets were negatively affected by the presence of associated plants,whereas,in another case(H.spinosa),fruit set and seed set were higher and unaffected when ecosystem engineers bloomed with associated plants,respectively.Our findings suggest that besides experiencing direct costs,ecosystem engineers can also benefit from facilitating other species via increasing their own visibility to pollinators.Thus,we highlight that pollination interactions can compensate for costs of facilitation depending on ecosystem engineer species.This study illuminates how the outcome of direct plant–plant interactions might be mediated by indirect interactions including third players.
