As an important means regulating the relationship between human and natural ecosystem,ecological restoration program plays a key role in restoring ecosystem functions.The Grain-for-Green Program(GFGP,One of the world...As an important means regulating the relationship between human and natural ecosystem,ecological restoration program plays a key role in restoring ecosystem functions.The Grain-for-Green Program(GFGP,One of the world’s most ambitious ecosystem conservation set-aside programs aims to transfer farmland on steep slopes to forestland or grassland to increase vegetation coverage)has been widely implemented from 1999 to 2015 and exerted significant influence on land use and ecosystem services(ESs).In this study,three ecological models(In VEST,RUSLE,and CASA)were used to accurately calculate the three key types of ESs,water yield(WY),soil conservation(SC),and net primary production(NPP)in Karst area of southwestern China from 1982 to 2015.The impact of GFGP on ESs and trade-offs was analyzed.It provides practical guidance in carrying out ecological regulation in Karst area of China under global climate change.Results showed that ESs and trade-offs had changed dramatically driven by GFGP.In detail,temporally,SC and NPP exhibited an increasing trend,while WY exhibited a decreasing trend.Spatially,SC basically decreased from west to east;NPP basically increased from north to south;WY basically increased from west to east;NPP and SC,SC and WY developed in the direction of trade-offs driven by the GFGP,while NPP and WY developed in the direction of synergy.Therefore,future ecosystem management and restoration policy-making should consider trade-offs of ESs so as to achieve sustainable provision of ESs.展开更多
The Grain-for-Green Policy in China could not only improve China's ecological quality, but also influence grain supplies for a short term. Based on data from the detailed nationwide land use survey in 1996 and the st...The Grain-for-Green Policy in China could not only improve China's ecological quality, but also influence grain supplies for a short term. Based on data from the detailed nationwide land use survey in 1996 and the steep cultivated land survey update in 2000, a regression model for the driving forces affecting steep cultivated lands was developed, and cluster analysis was used to identify seven steep cultivated land types in order to analyze the grain availability impact of the project with land usage estimates for 2010 and 2030. The results suggested that consecutive days with minimum daily temperature over 10 ℃ and the dominant slope in a county constrained the spatial distribution of steep cultivated lands. In terms of socioeconomic factors, steep cultivated land was a complex interaction of population size, gross domestic production level, and the richness and quality of cultivated lands having slopes less then 15°. The trends for steep cultivated land in 2010 and 2030 were forecast using a driving forces model and China's grain security criteria and showed that the Grain-for-Green Policy at the national level would not cause a grain shortage or threaten food security criteria. However, if steep sloped lands were to be retired from production, some regions would need grain supplements as early as 2010. Also, assuming that only 60% of the cultivated land at the national level was needed, population and economic development pressures in 2030 would require some steep cultivated lands to be used for grain production.展开更多
Ever since the disastrous floods of 1998, the Chinese government has used the Natural Forest Protection and Sloping Land Conversion Programs to promote afforestation and reforestation as means to reduce runoff, contro...Ever since the disastrous floods of 1998, the Chinese government has used the Natural Forest Protection and Sloping Land Conversion Programs to promote afforestation and reforestation as means to reduce runoff, control erosion, and stabilize local livelihoods. These two ambitious programs have been reported as large-scale successes, contributing to an overall increase in China’s forest cover and to the stated goals of environmental stabilization. A small-scale field study at the project level of the implementation of these two programs in Baiwu Township, Yanyuan County, Sichuan, casts doubt upon the accuracy and reliability of these claims of success; ground observations revealed utter failure in some sites and only marginal success in others. Reasons for this discrepancy are posited as involving ecological, economic, and bureaucratic factors. Further research is suggested to determine whether these discrepancies are merely local aberrations or represent larger-scale failures in reforestation programs.展开更多
土地利用变化对区域水循环具有重要影响,土地利用决策就是水资源决策,这一命题已经被诸多研究证实并被研究者和决策者所认识。本文以黄河流域中游的伊洛河上游流域为研究区域,应用分布式流域农业生态水文模型SWAT(Soil and Water Assess...土地利用变化对区域水循环具有重要影响,土地利用决策就是水资源决策,这一命题已经被诸多研究证实并被研究者和决策者所认识。本文以黄河流域中游的伊洛河上游流域为研究区域,应用分布式流域农业生态水文模型SWAT(Soil and Water Assessment Tool),在我国退耕还林还草的生态恢复和重建的重大背景下,分别设置了6种不同的土地利用变化情景,基于蓝水和绿水的视角,研究土地利用/覆被对流域水循环的影响。本文对SWAT模型输出的月径流结果进行了率定和验证,证明该模型对研究流域水文循环的模拟达到了可接受水平的准确性与合理性。采用单因素方差分析和多重比较,分析基于不同水文年型下土地利用变化对各水文要素变化的影响。结果表明:1)2010 2015年多年平均降水资源总量为34.94亿m^3,多年平均蓝水绿水资源总量为34.09亿m^3,蓝水资源量占多年蓝水绿水资源总量的33.73%,绿水资源量占多年蓝水绿水资源总量的66.27%。2)不同情景退耕还林或还草,蓝水资源量均减少,绿水流均增加,绿水库均减少。在丰水年和平水年,退耕还林还草对蓝水资源量中地表径流分量影响较明显。该结论对于加深认识伊洛河上游流域土地利用/覆被和水资源的相互关系具有一定意义,为该区域高效合理利用水土资源提供了科学依据。展开更多
The Grain-for-Green Policy aims to convert cropland to grassland and forest across western China, and evaluating ecological risk is essential to its implementation. Because few recent studies have focused on eco-risk ...The Grain-for-Green Policy aims to convert cropland to grassland and forest across western China, and evaluating ecological risk is essential to its implementation. Because few recent studies have focused on eco-risk changes of land use in the areas affected by significant policies, this paper took Zhengning County in Gansu Province as our focal area, and studied spatial-temporal changes in ecological risk before and after policy implementation. Based on indices of landscape fragmentation and ecosystem service value, an ecological risk assessment method using ArcGIS and Fragstats was done. The regional gravity center model and land spatial distribution model were also used to enrich the quantitative description of divisional eco-risk and its spatial-temporal variation in the county. Results showed that the implementation of the policy has contributed to an overall reduction in ecological risk in Zhengning County, with a divisional degree order reduction following the pattern: eastern Zhengning 〉 western Zhengning 〉 central Zhengning. The gravity center for eco-risk shifted 4288 m southwest from 1995 to 2010 due to landscape fragmentation. The study implies that greater attention should be paid to forest and grassland restoration in eastern Zhengning, cropland protection in central Zhengning, and soil and water conservation in western Zhengning.展开更多
Initially intended to prevent water and soil erosion, China's Grain-for-Green Project (GGP) also has had economic impacts on farmers'incorne and employment. Based on the poverty monitoring survey data between 2006...Initially intended to prevent water and soil erosion, China's Grain-for-Green Project (GGP) also has had economic impacts on farmers'incorne and employment. Based on the poverty monitoring survey data between 2006-2010 from National Bureau of Statistics (NBS), this paper evaluates the GGP's policy effects with respect to farmers' income, non-agricultural employment and poverty alleviation. Our findings suggest that contributing to the GGP, farmers' income including GGP subsidies increased significantly compared with the pre-GGP level," however, if GGP subsidies are not taken into account, the increase in farmers'non-agricultural income after the GGP could only compensate.for the income losses from farmland reduction, showing an insignificant effect. Second, there exist significant differences on employment tendency among GGP households. High-income households tend to engage in operation business in forestry, livestock and fishery activities, while medium-income families are more inclined to seek employment outside, and the differences attribute to the inter-group intrinsic characteristics. Lastly, the GGP's poverty alleviation effect varies with the difference in poverty standard. Overall the GGP's poverty alleviation effect is significant.展开更多
Evaluation of the ecological effects of eco-compensation policies helps analyze policy rationality and feasibility and provides scientific and practical bases for perfecting eco-compensation systems. Taking the key ec...Evaluation of the ecological effects of eco-compensation policies helps analyze policy rationality and feasibility and provides scientific and practical bases for perfecting eco-compensation systems. Taking the key ecological function area of the Loess Plateau, China as a case study, we have evaluated ecosystem responses to the Grain-for-Green Project that commenced in 1999. Six indicators were selected to assess changes in ecosystem structure, quality and function. The results showed that implementation of the Grain-for-Green Project has reduced sloping cropland by 1571 km2 and increased ecological land by 1337 km2. The increase in ecological land alters ecosystem structures across the study area and the decline in sloping cropland reduces farming activity interference; both of these are conducive to the restoration of natural vegetation. From 2000 to 2010, the vegetation cover of grassland, desert and forest ecosystems increased 10.89%, 8.34% and 4.24% respectively and average NPP rose 51%, with an average annual growth rate of around 5%. This indicates that eco-compensation has promoted the improvement of ecosystem quality. Total biomass of ecosystems increased two times on average from 2000 to 2010, meaning that the carbon sequestration capacity of ecosystems also increased. The reduction in the area of water loss and soil erosion and the increase in retained runoff by forests indicate an improvement in ecosystem function and services on the Loess Plateau.展开更多
Mu Us Sandy Land(MUSL) of China, as a typical eco-fragile and farming-pastoral transitional region, shows great vulnerability to disturbances from cultivation activity. In this region, the conflict between cultivation...Mu Us Sandy Land(MUSL) of China, as a typical eco-fragile and farming-pastoral transitional region, shows great vulnerability to disturbances from cultivation activity. In this region, the conflict between cultivation activity and environmental protection has not attracted great importance until the implementation of China's Grain-for-Green Policy(CGGP) since2000. Here, using Landsat5 TM/Landsat7 ETM+ images from 1990, 2000, and 2010, we monitor the cultivation activity and land-use/cover changes(LUCC) resulting from cultivation activity in the MUSL region. Based on the data from images, we developed a series of databases of cultivated activity-induced LUCC and use them to discuss comparatively the spatio-temporal evolution trends of cultivation activity before and after CGGP implementation. These results provide evidence for managers to evaluate the implementation effectiveness of governmental policy and the influence of cultivation activity on the ecological environment of the MUSL region.展开更多
基金Under the auspices of National Key Technology Research and Development Project of China(No.2018YFC0507301-02)Chinese Academy of Sciences,Strategic Pilot Science and Technology Project(Class A)(No.XDA2002040201)Shaanxi Province Natural Science Basic Research Project(No.2018JM4016)
文摘As an important means regulating the relationship between human and natural ecosystem,ecological restoration program plays a key role in restoring ecosystem functions.The Grain-for-Green Program(GFGP,One of the world’s most ambitious ecosystem conservation set-aside programs aims to transfer farmland on steep slopes to forestland or grassland to increase vegetation coverage)has been widely implemented from 1999 to 2015 and exerted significant influence on land use and ecosystem services(ESs).In this study,three ecological models(In VEST,RUSLE,and CASA)were used to accurately calculate the three key types of ESs,water yield(WY),soil conservation(SC),and net primary production(NPP)in Karst area of southwestern China from 1982 to 2015.The impact of GFGP on ESs and trade-offs was analyzed.It provides practical guidance in carrying out ecological regulation in Karst area of China under global climate change.Results showed that ESs and trade-offs had changed dramatically driven by GFGP.In detail,temporally,SC and NPP exhibited an increasing trend,while WY exhibited a decreasing trend.Spatially,SC basically decreased from west to east;NPP basically increased from north to south;WY basically increased from west to east;NPP and SC,SC and WY developed in the direction of trade-offs driven by the GFGP,while NPP and WY developed in the direction of synergy.Therefore,future ecosystem management and restoration policy-making should consider trade-offs of ESs so as to achieve sustainable provision of ESs.
基金Project supported by the Program for Changjiang Scholars and Innovative Research Teams in University (PCSIRT), China (No. IRT0412) and the Ministry of Land and Resources, China (No. 2003-2.2-2).
文摘The Grain-for-Green Policy in China could not only improve China's ecological quality, but also influence grain supplies for a short term. Based on data from the detailed nationwide land use survey in 1996 and the steep cultivated land survey update in 2000, a regression model for the driving forces affecting steep cultivated lands was developed, and cluster analysis was used to identify seven steep cultivated land types in order to analyze the grain availability impact of the project with land usage estimates for 2010 and 2030. The results suggested that consecutive days with minimum daily temperature over 10 ℃ and the dominant slope in a county constrained the spatial distribution of steep cultivated lands. In terms of socioeconomic factors, steep cultivated land was a complex interaction of population size, gross domestic production level, and the richness and quality of cultivated lands having slopes less then 15°. The trends for steep cultivated land in 2010 and 2030 were forecast using a driving forces model and China's grain security criteria and showed that the Grain-for-Green Policy at the national level would not cause a grain shortage or threaten food security criteria. However, if steep sloped lands were to be retired from production, some regions would need grain supplements as early as 2010. Also, assuming that only 60% of the cultivated land at the national level was needed, population and economic development pressures in 2030 would require some steep cultivated lands to be used for grain production.
文摘Ever since the disastrous floods of 1998, the Chinese government has used the Natural Forest Protection and Sloping Land Conversion Programs to promote afforestation and reforestation as means to reduce runoff, control erosion, and stabilize local livelihoods. These two ambitious programs have been reported as large-scale successes, contributing to an overall increase in China’s forest cover and to the stated goals of environmental stabilization. A small-scale field study at the project level of the implementation of these two programs in Baiwu Township, Yanyuan County, Sichuan, casts doubt upon the accuracy and reliability of these claims of success; ground observations revealed utter failure in some sites and only marginal success in others. Reasons for this discrepancy are posited as involving ecological, economic, and bureaucratic factors. Further research is suggested to determine whether these discrepancies are merely local aberrations or represent larger-scale failures in reforestation programs.
文摘土地利用变化对区域水循环具有重要影响,土地利用决策就是水资源决策,这一命题已经被诸多研究证实并被研究者和决策者所认识。本文以黄河流域中游的伊洛河上游流域为研究区域,应用分布式流域农业生态水文模型SWAT(Soil and Water Assessment Tool),在我国退耕还林还草的生态恢复和重建的重大背景下,分别设置了6种不同的土地利用变化情景,基于蓝水和绿水的视角,研究土地利用/覆被对流域水循环的影响。本文对SWAT模型输出的月径流结果进行了率定和验证,证明该模型对研究流域水文循环的模拟达到了可接受水平的准确性与合理性。采用单因素方差分析和多重比较,分析基于不同水文年型下土地利用变化对各水文要素变化的影响。结果表明:1)2010 2015年多年平均降水资源总量为34.94亿m^3,多年平均蓝水绿水资源总量为34.09亿m^3,蓝水资源量占多年蓝水绿水资源总量的33.73%,绿水资源量占多年蓝水绿水资源总量的66.27%。2)不同情景退耕还林或还草,蓝水资源量均减少,绿水流均增加,绿水库均减少。在丰水年和平水年,退耕还林还草对蓝水资源量中地表径流分量影响较明显。该结论对于加深认识伊洛河上游流域土地利用/覆被和水资源的相互关系具有一定意义,为该区域高效合理利用水土资源提供了科学依据。
基金National Natural Science Foundation of China (No. 40971282)
文摘The Grain-for-Green Policy aims to convert cropland to grassland and forest across western China, and evaluating ecological risk is essential to its implementation. Because few recent studies have focused on eco-risk changes of land use in the areas affected by significant policies, this paper took Zhengning County in Gansu Province as our focal area, and studied spatial-temporal changes in ecological risk before and after policy implementation. Based on indices of landscape fragmentation and ecosystem service value, an ecological risk assessment method using ArcGIS and Fragstats was done. The regional gravity center model and land spatial distribution model were also used to enrich the quantitative description of divisional eco-risk and its spatial-temporal variation in the county. Results showed that the implementation of the policy has contributed to an overall reduction in ecological risk in Zhengning County, with a divisional degree order reduction following the pattern: eastern Zhengning 〉 western Zhengning 〉 central Zhengning. The gravity center for eco-risk shifted 4288 m southwest from 1995 to 2010 due to landscape fragmentation. The study implies that greater attention should be paid to forest and grassland restoration in eastern Zhengning, cropland protection in central Zhengning, and soil and water conservation in western Zhengning.
基金sponsored by the National Natural Science Foundation of China(NSFC)"Seeking the Most Effective Means to Reduce Household Income Gaps in China"(Grant No.71473257)
文摘Initially intended to prevent water and soil erosion, China's Grain-for-Green Project (GGP) also has had economic impacts on farmers'incorne and employment. Based on the poverty monitoring survey data between 2006-2010 from National Bureau of Statistics (NBS), this paper evaluates the GGP's policy effects with respect to farmers' income, non-agricultural employment and poverty alleviation. Our findings suggest that contributing to the GGP, farmers' income including GGP subsidies increased significantly compared with the pre-GGP level," however, if GGP subsidies are not taken into account, the increase in farmers'non-agricultural income after the GGP could only compensate.for the income losses from farmland reduction, showing an insignificant effect. Second, there exist significant differences on employment tendency among GGP households. High-income households tend to engage in operation business in forestry, livestock and fishery activities, while medium-income families are more inclined to seek employment outside, and the differences attribute to the inter-group intrinsic characteristics. Lastly, the GGP's poverty alleviation effect varies with the difference in poverty standard. Overall the GGP's poverty alleviation effect is significant.
基金the National Science and Technology Support Program(2013BAC03B05)National Natural Science Foundation of China(41371486)
文摘Evaluation of the ecological effects of eco-compensation policies helps analyze policy rationality and feasibility and provides scientific and practical bases for perfecting eco-compensation systems. Taking the key ecological function area of the Loess Plateau, China as a case study, we have evaluated ecosystem responses to the Grain-for-Green Project that commenced in 1999. Six indicators were selected to assess changes in ecosystem structure, quality and function. The results showed that implementation of the Grain-for-Green Project has reduced sloping cropland by 1571 km2 and increased ecological land by 1337 km2. The increase in ecological land alters ecosystem structures across the study area and the decline in sloping cropland reduces farming activity interference; both of these are conducive to the restoration of natural vegetation. From 2000 to 2010, the vegetation cover of grassland, desert and forest ecosystems increased 10.89%, 8.34% and 4.24% respectively and average NPP rose 51%, with an average annual growth rate of around 5%. This indicates that eco-compensation has promoted the improvement of ecosystem quality. Total biomass of ecosystems increased two times on average from 2000 to 2010, meaning that the carbon sequestration capacity of ecosystems also increased. The reduction in the area of water loss and soil erosion and the increase in retained runoff by forests indicate an improvement in ecosystem function and services on the Loess Plateau.
基金funded by the China National Key Basic Research Programme (2013CB429901)the National Natural Science Foundation of China (General Programme: 41171400)+1 种基金Youth Innovation Promotion Association, CAS (2016158)the National Key Research and Development Program of China (2016YFC0503706)
文摘Mu Us Sandy Land(MUSL) of China, as a typical eco-fragile and farming-pastoral transitional region, shows great vulnerability to disturbances from cultivation activity. In this region, the conflict between cultivation activity and environmental protection has not attracted great importance until the implementation of China's Grain-for-Green Policy(CGGP) since2000. Here, using Landsat5 TM/Landsat7 ETM+ images from 1990, 2000, and 2010, we monitor the cultivation activity and land-use/cover changes(LUCC) resulting from cultivation activity in the MUSL region. Based on the data from images, we developed a series of databases of cultivated activity-induced LUCC and use them to discuss comparatively the spatio-temporal evolution trends of cultivation activity before and after CGGP implementation. These results provide evidence for managers to evaluate the implementation effectiveness of governmental policy and the influence of cultivation activity on the ecological environment of the MUSL region.