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...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 than 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
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
Soil erosion becomes a serious environmental problem in the world, especially in western China. An effective management practice called the Grain for Green Program(GGP), which was launched in 1999, aims to reduce soil...Soil erosion becomes a serious environmental problem in the world, especially in western China. An effective management practice called the Grain for Green Program(GGP), which was launched in 1999, aims to reduce soil and water loss and alleviate the ecological environment problem in western China. Two typical counties in western China, the Zhongxian(in Chongqing Municipality) and Ansai(in Shaanxi Province) were chosen to evaluate the dynamic changes of land use and agricultural production structure before and after the implementation of the Program in this paper. The results showed that the cultivated land area was reduced by 7.08% from 1989 to 2003. The cultivated land per person was decreased by 8.42% during 1999-2003. Moreover, the stability index of the secondary sector of the economy was increased from 0.91 in the period 1990-1999 to 0.94 in the following ten years. In addition, the stability index of tertiary economic sector increased from 0.88 to 0.92 in Zhongxian county. Meanwhile, the cultivated land area was reduced by 15.48% from 1990 to 1999. The soil erosion modulus was decreased by 33.33% from 1999 to 2006. Also, the stability index of secondary and tertiary economic sectors was 0.86 in the period 1998-2002. However, it decreased by 77% during 2002 to 2007 in Ansai County. These results imply that the Grain for Green Program had different impact on the two regions. Several effective strategies of soil and water conservation have been carried out to ameliorate the sustainable development of ecological environment and economy in these two counties of western China.展开更多
China has promulgated a series of policies including the Western Development Program, the Grain for Green Project, agricultural support policies and building a new countryside strategy to eliminate east-west differenc...China has promulgated a series of policies including the Western Development Program, the Grain for Green Project, agricultural support policies and building a new countryside strategy to eliminate east-west differences and urban-rural disparities since the late 1990s. This paper gives a holistic examination on local responses to the four typical macro socio-economic development policies and their effects on rural system based on a case study of a mountainous village in southern Sichuan Province. The results showed that the policies have not moved the case study village from its historically marginal status. To some extent, its socio-economic situation might have been worsened by accelerated out- migration of the youth, loss of agricultural land due to afforestation and industrial plants, increased fire hazard due to afforestation and reforestation, increased environmental pollution due to industrial enterprises attracted to the village and a steep decline in agricultural production due to loss of and inefficient use of cultivated land. Factors causing local villages' dilemmas include the nonuniformity of actors' objectives, finiteness of villagers' abilities, and the imperfect incentive and restraint mechanism for local government's activities under existing policy framework composed of uncoordinated one-size-fits- all policies. We suggest that China's rural policy in the new period should gradually shift from a sectoral to a place-based one, from top-down incentives to the development of bottom-up projects, and fully recognize the diversity of rural space, so as to lift localcapacities and make good use of the knowledge shared by different actors. Moreover, it is also necessary to integrate the various sectoral policies, and improve the interministerial and interdepartmental coordination of rural policies at regional and local levels.展开更多
实施退耕还林,是控制中国水土流失、改善生态环境的有效途径。如何制定最具成本-效益的退耕还林方案,以平衡生态、经济和粮食安全之间的矛盾,是保证退耕还林工程可持续发展的关键。该研究以淮河上游的息县流域为研究区,在土地利用现状...实施退耕还林,是控制中国水土流失、改善生态环境的有效途径。如何制定最具成本-效益的退耕还林方案,以平衡生态、经济和粮食安全之间的矛盾,是保证退耕还林工程可持续发展的关键。该研究以淮河上游的息县流域为研究区,在土地利用现状的基础上,一方面通过建立分布式水文模型SWAT(soil and water assessment tool)依次模拟各子流域的退耕还林操作得到泥沙削减系数,另一方面通过GDP(gross domestic product)与土地利用现状的空间叠置分析得到各子流域进行退耕还林的GDP损失系数,据此分别构成退耕还林的减沙效益目标和经济效益目标,采用多目标遗传算法NSGA-II优化求解子流域尺度的退耕还林方案。研究结果表明:1)建立的SWAT模型对研究区径流和泥沙的模拟精度较高,Nash系数分别在0.90和0.70以上,决定系数均大于0.80,且百分比偏差均控制在-20%~20%以内,可认为SWAT模型能够用于评估退耕还林的泥沙削减效果;2)子流域泥沙削减系数范围为26.70~2675.85 t/km^(2),并表现出从上游到下游逐渐减小的趋势,说明在流域上游的河源区实施单位面积的退耕还林能够取得更好的泥沙控制效果;3)子流域GDP损失系数在空间上呈现出较大的差异性,既有子流域出现了GDP的增加也有子流域出现了GDP的减小,对比发现在行政市或县主要居民点所在的子流域进行退耕还林需要付出更大的经济代价;4)多目标优化求解得到的退耕还林方案集将人均耕地面积维持在1.04×10^(−3)~1.54×10^(−3) km^(2),明显高于粮食安全的警戒水平,同时该方案集能够在仅损失30.13%~37.67%经济产值的同时将泥沙产量削减53.54%~69.86%,并达到区域可持续发展的土壤侵蚀水平。该研究提出的基于生态减沙效益和经济效益的子流域尺度退耕还林优化方法可为流域水土保持、退耕还林工程的科学规划提供借鉴和指导。展开更多
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 than 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.
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.
基金the Foundation of National Key Science and Technology Program (2011BAD31B03)the National Natural Science Foundation of China (41001163)+1 种基金Western Light Western Doctor of CAS, the international cooperation program of Sichuan province (2013HH0016)CAS West Action: Experimental and Demonstrational study on soil and water losses and non-point pollution in the Three Gorges (KZCX2-XB3-09)
文摘Soil erosion becomes a serious environmental problem in the world, especially in western China. An effective management practice called the Grain for Green Program(GGP), which was launched in 1999, aims to reduce soil and water loss and alleviate the ecological environment problem in western China. Two typical counties in western China, the Zhongxian(in Chongqing Municipality) and Ansai(in Shaanxi Province) were chosen to evaluate the dynamic changes of land use and agricultural production structure before and after the implementation of the Program in this paper. The results showed that the cultivated land area was reduced by 7.08% from 1989 to 2003. The cultivated land per person was decreased by 8.42% during 1999-2003. Moreover, the stability index of the secondary sector of the economy was increased from 0.91 in the period 1990-1999 to 0.94 in the following ten years. In addition, the stability index of tertiary economic sector increased from 0.88 to 0.92 in Zhongxian county. Meanwhile, the cultivated land area was reduced by 15.48% from 1990 to 1999. The soil erosion modulus was decreased by 33.33% from 1999 to 2006. Also, the stability index of secondary and tertiary economic sectors was 0.86 in the period 1998-2002. However, it decreased by 77% during 2002 to 2007 in Ansai County. These results imply that the Grain for Green Program had different impact on the two regions. Several effective strategies of soil and water conservation have been carried out to ameliorate the sustainable development of ecological environment and economy in these two counties of western China.
基金supported by the National Natural Science Foundation of China(Grant Nos.41201176,41130748and41171149)China Postdoctoral Science Foundation(Grant Nos.2011M500029 and 2012T50126)
文摘China has promulgated a series of policies including the Western Development Program, the Grain for Green Project, agricultural support policies and building a new countryside strategy to eliminate east-west differences and urban-rural disparities since the late 1990s. This paper gives a holistic examination on local responses to the four typical macro socio-economic development policies and their effects on rural system based on a case study of a mountainous village in southern Sichuan Province. The results showed that the policies have not moved the case study village from its historically marginal status. To some extent, its socio-economic situation might have been worsened by accelerated out- migration of the youth, loss of agricultural land due to afforestation and industrial plants, increased fire hazard due to afforestation and reforestation, increased environmental pollution due to industrial enterprises attracted to the village and a steep decline in agricultural production due to loss of and inefficient use of cultivated land. Factors causing local villages' dilemmas include the nonuniformity of actors' objectives, finiteness of villagers' abilities, and the imperfect incentive and restraint mechanism for local government's activities under existing policy framework composed of uncoordinated one-size-fits- all policies. We suggest that China's rural policy in the new period should gradually shift from a sectoral to a place-based one, from top-down incentives to the development of bottom-up projects, and fully recognize the diversity of rural space, so as to lift localcapacities and make good use of the knowledge shared by different actors. Moreover, it is also necessary to integrate the various sectoral policies, and improve the interministerial and interdepartmental coordination of rural policies at regional and local levels.
文摘实施退耕还林,是控制中国水土流失、改善生态环境的有效途径。如何制定最具成本-效益的退耕还林方案,以平衡生态、经济和粮食安全之间的矛盾,是保证退耕还林工程可持续发展的关键。该研究以淮河上游的息县流域为研究区,在土地利用现状的基础上,一方面通过建立分布式水文模型SWAT(soil and water assessment tool)依次模拟各子流域的退耕还林操作得到泥沙削减系数,另一方面通过GDP(gross domestic product)与土地利用现状的空间叠置分析得到各子流域进行退耕还林的GDP损失系数,据此分别构成退耕还林的减沙效益目标和经济效益目标,采用多目标遗传算法NSGA-II优化求解子流域尺度的退耕还林方案。研究结果表明:1)建立的SWAT模型对研究区径流和泥沙的模拟精度较高,Nash系数分别在0.90和0.70以上,决定系数均大于0.80,且百分比偏差均控制在-20%~20%以内,可认为SWAT模型能够用于评估退耕还林的泥沙削减效果;2)子流域泥沙削减系数范围为26.70~2675.85 t/km^(2),并表现出从上游到下游逐渐减小的趋势,说明在流域上游的河源区实施单位面积的退耕还林能够取得更好的泥沙控制效果;3)子流域GDP损失系数在空间上呈现出较大的差异性,既有子流域出现了GDP的增加也有子流域出现了GDP的减小,对比发现在行政市或县主要居民点所在的子流域进行退耕还林需要付出更大的经济代价;4)多目标优化求解得到的退耕还林方案集将人均耕地面积维持在1.04×10^(−3)~1.54×10^(−3) km^(2),明显高于粮食安全的警戒水平,同时该方案集能够在仅损失30.13%~37.67%经济产值的同时将泥沙产量削减53.54%~69.86%,并达到区域可持续发展的土壤侵蚀水平。该研究提出的基于生态减沙效益和经济效益的子流域尺度退耕还林优化方法可为流域水土保持、退耕还林工程的科学规划提供借鉴和指导。
