资源预览内容
第1页 / 共52页
第2页 / 共52页
第3页 / 共52页
第4页 / 共52页
第5页 / 共52页
第6页 / 共52页
第7页 / 共52页
第8页 / 共52页
第9页 / 共52页
第10页 / 共52页
亲,该文档总共52页,到这儿已超出免费预览范围,如果喜欢就下载吧!
资源描述
区域可持续发展与人地关系行为机制模型研究,石 敏俊 筑波大学,区域可持续发展与人地关系行为机制模型研究,区域可持续发展与农业环境政策 人地关系行为机制模型框架的建立:外部社会经济因素影响人地关系变化的机制 鄂尔多斯高原:人地关系行为机制模型与退耕还林对水土保持影响的比较静态模拟 自然科学与社会科学相融合的必要性,区域可持续发展与农业环境政策,欧美国家的农业环境政策 石油农业的化肥农药高投入导致水质污染等环境问题 价格支持政策导致农产品过剩 农业环境政策的核心是推行农业粗放化经营,减少化肥农药投入,减少农产品产量 对于实行粗放经营的农户给予政策补贴,发展中国家的农业环境问题,土地退化引起的农业环境问题 沙漠化,水土流失,盐碱化 环境负荷引起的农业环境问题 水质污染,土壤污染 土地退化的人为因素 人口压力,农业技术水平 依赖资源投入的静态增长导致农业粗放再生产和土地利用的平面扩张,土地利用超过环境容量时带来土地退化,发展中国家的农业可持续发展,解决土地退化问题的出路在于发展可持续集约农业 可持续集约农业:通过集约化达到可持续 集约化:对少量土地实行集约经营,技术密集投入,提高单位土地面积生产力水平,为大面积退化土地休生养息恢复生态、实现区域可持续发展提供条件,保护环境与发展经济的关系,发展中国家的农业环境政策,解决土地退化问题的农业环境政策应当结合发展可持续集约农业来展开 发展可持续集约农业的关键是技术进步,开发实用适用技术 实用:实际农业活动中可应用的技术 适用:适合当地条件适合当地农户采用的技术 发展集约化(技术进步和技术推广)的政策补贴可作为环境保护投资进入环境经济核算,人地关系行为机制模型框架:社会经济因素影响人地关系变化的机制,影响人地关系和环境生态变化的社会经济因素 人口增长 市场和价格变动 技术进步 制度和政策 收入和消费期望 单一或综合的因果关系分析不能阐明社会经济因素影响人地关系变化的机制,Resource Environment,Land Use Agricultural Activity,Institution Policy,Technology,Market Price,Resource Constraint,Impact on Environment,Population growth,外部社会经济环境与人地关系变化,Literature review,Farm household decisions on land use activities and technological choice affect the soil quality and therefore play an important role in aggravating or reducing land degradation process. Farm household decisions are dependent on relative prices of output, input and production factors, and other socio-economic circumstances that are influenced by macroeconomic and agricultural policy. Agricultural policies affect soil degradation by influencing the level of output, input and factor prices (Heerink, 2001).,社会经济因素影响环境变化的机制,政策和制度外部社会经济环境农户经济行为资源环境变化 反馈:资源环境变化农户经济行为(资源环境退化对经济福利的影响,现在价值与将来价值的关系) 外部社会经济环境变化:价格变动,技术进步,资金和信用约束 政策和制度:经济政策和环境政策,资源分配和资源利用秩序,Conceptual framework,Policy reform,Socio-economic environment,Household decision,Land degradation,Macro and Regional Models,Household and Village Models,Bio-economic Models,Bio-economic household Model,Bio-economic village Model approach,Econometric estimation approach: Lack of consistent data, especially long time series data about effect of soil degradation; Difficult to derive function form of the reduced-form equation. Meta modeling (Decision rule) approach: Estimate a statistical relationship between exogenous and relevant endogenous variables; refer to a black-box representation of relationship between exogenous and endogenous variables;,Bio-economic village Model - continue,Mathematical programming approach: A major advantage of LP Model is that can combine economic behavior and biophysical process in an integrated framework. Leontief input-output coefficients permits the combination of incompatible economic and biophysical production function. A disadvantage of LP Model is that may generate vast amount of what-if results if some of parameters of the model are not known with great accuracy.,鄂尔多斯高原人地关系行为机制模型,Bio-economic village LP Model Short-term analysis: one year due to uncertainty Village model: appreciate level of analysis Objective function:maximizing benefit of households Production function: Leontief input-output coefficients Consumption function:consumption choice based upon nutrition and prices under constraints of basic nutrition intake demand and hobby Soil conservation process: converted land supply Feedback of soil erosion to production:no feedback process,Bio-economic village LP Model,(1),s.t.,(2),(3),(4),(5),(6),Variable definition,: household discounted utility,: period,: crop,: land type,: land endowment,: the area of crop,produced on land type,in period,: the per unit price of crop or livestock output,: the yield function for production of crop c or livestock v,: a vector of inputs used in production of crop c or livestock v,: the per unit input price for input,Variable definition-continue,: the crop or livestock output,used for self-consumption,: the crop or livestock output,used for self-supply, such as fodder, draft animal,: the production of units of livestock,at period t,: livestock,: the wage level, such as seasonal off-farm wage, constant off-farm wage,hiring labor wage,: the off-farm labor supply of seasonal part-time labor or constant off-farm labor,: the hiring labor supply,: family labor,: family labor input for farm activities,: total labor input for farm activities,: discount rate,Modules of LP Model,Processes (73) Production (22): cropping corresponding to land type Corn, Millet, Potato, Sunflower, Rapeseed, Beans, Goat, Sheep, Hog, Cattle Sale (11): Corn, Millet, Potato, Sunflower, Rapeseed, Goat, Sheep, Hog, Mutton, Pork, Wool Self-consumption (6): Corn, Millet, Potato, Beans, Mutton, Pork Purchase (11): Wheat, Rice, Pork, Mutton, Beef, Vegetable, Fertilizers, Pesticide, seeds, Coal Self-supply (5): Seeds, Fodder, Manure, Firewood Resource supply(17): Land supply(6), Labor supply(11) Land degradation (1): Soil erosion,Modules of LP Model - continue,Constraints (70) Products (12): Resources (30): land constraints (7); labor time constraints (13); labor allocation constraints (10): family labor (3), hiring
网站客服QQ:2055934822
金锄头文库版权所有
经营许可证:蜀ICP备13022795号 | 川公网安备 51140202000112号