【作者】 付永；

【导师】 曾菊新；

【作者基本信息】 华中师范大学 ， 人文地理学， 2008， 博士

【摘要】 由于农用化学品(化肥、农药)的大量施用引起的面源污染是当前中国农村面临的一个突出环境问题,它对人民群众身心健康、农村经济社会可持续发展都造成了严重影响。本文依托国家自然科学基金项目“江汉平原乡村住区系统演变与人居环境优化研究(40671050)”,从面源污染日趋恶化的基本事实出发,将问题置于城乡二元结构转换的背景下,采用实证分析与制度分析等方法,从宏观、微观以及制度三个层面研究城乡二元结构转换进程中面源污染的形成机理.尝试构建面源污染分析的基本框架,力求为低成本地控制与治理面源污染提出相应的政策建议。文章的主要观点是:在城乡二元结构转换进程中,我国农业发展中出现的面源污染,是农业结构调整、农户行为选择与制度激励综合作用的结果。全文可分为五个部分,共七章。第一部分为第一章导言。旨在引出问题.提出问题并确定研究思路,并对文章的逻辑结构、研究内容、研究方法、创新与不足予以简要说明。第二部分包括第二章和第三章,属宏观分析部分。研究我国农业结构调整的环境效应。第二章阐述了农业生产与环境之间关系的相互性,它们之间的相互关系在于,作为主要的土地利用活动,农业是影响环境的一个主要力量,同时,农业自身严重依赖环境本身。城乡二元结构转换进程中,我国农业发展的驱动力主要来源于农业结构变化。农业结构变化,以及农业结构变化中出现的要素替代,使我国农用化学品施用量在近三十年来快速增长。但是,这些变化部分地损害了农业与环境之间的相互性,面源污染加剧。第三章为结构调整环境效应的理论解释,并运用时间序列资料予以实证检验。作者构建了一个结构调整的环境效应的简单模型,模型显示结构调整对环境的影响既可能是正面的,也可能是负面的,关键在于结构调整的方向。农业产业结构调整与农业投入变化的区域分析结果表明,与结构上的变化相对应,不论是化肥或农药,大部分地区投入总量逐渐攀升,投入强度也呈上升趋势。中国的农业发展及其结构调整,已使相当部分地区的农业发展模式从主要依靠传统投入大步向依靠资本投入的资本化模式转变,形成“高投入、高产出、高排放”的农业发展格局。上述命题经协整分析与Grange因果关系检验得到证实。第三部分包括第四章和第五章,属农户农用化学品投入行为的微观研究。农业产业结构调整与要素投入的变化本质上是农户基于经济行为决策的结果。第四章研究农户的化肥投入行为。对我国农户化肥投入水平的实证分析表明,平均而言化肥的产出弹性相当小,约为0.1,农户在农作实践使用了过量的化肥:影响农户化肥施用决策的因素主要是三个,分别是户均从业人员、省内城市化水平与户均纯收入。实证研究结果显示,在我国人口持续增长的条件下,增加化肥施用量保证粮食产出仍然是农户的首要选择,但农户弃用了传统的施用有机肥保养地力的方法。这与城乡二元结构转换进程中城市化进程对农民的吸引力越来越大,影响并改变了农户劳动的机会成本有关。第五章研究农户的农药投入行为。对农户在三种作物(玉米、小麦和晚稻)施用农药的实证分析显示,农药这种要素投入的产出弹性同样非常低,没有超过0.1。这么低的弹性意味着,当农药施用量增加带来的边际产出很小时,农户仍然选择增加农药的投入。农户施用农药主要受户均耕地、收入、农药价格、农户从业人员、非粮食作物率等因素的影响。农户农用化学品施用行为的微观分析得出了令人并不意外的结论,农户在化肥、农药这两种重要的要素投入上,均偏离了最优投入点,形成浪费。并产生了所认知的环境后果——面源污染。第四部分为第六章,属农户环境经济行为的制度分析。我国农用化学品的大量、广泛施用,有着深刻的制度方面的原因。农地制度的产权残缺使农户在生产活动中形成了短期收益偏好型的行为特征,农户重土地利用轻土地养护,重短期见效快的投入而舍长期具效益但短期效益不明显的投入,有多施农用化学品的激励,这种特征让农用化学品的大量施用成为“可能”;鼓励型的农用化学品生产制度安排、促销型的农用化学品销售安排及其存在的问题放大了农地产权残缺对农户施用农用化学品行为的激励,使“可能”变为“现实”。第五部分为第七章,是全文的总结。基于本文的分析逻辑与结论,我国农业面源污染控制与治理,应以改变农户的微观激励为主导,以调整农户行为为重点,以区域集约化农区面源污染治理为突破口,建立起法律、经济与行政手段相结合的农业面源污染控制体系。控制农业生产的环境外部成本,要充分考虑政策施加的执行成本和交易成本,平衡政策的收益与成本。从根本上说,减少农业发展造成的环境损害,控制与治理面源污染,发展资源节约和环境友好型的农业发展模式是正途。本文力求在以下四个方面有所作为与创新:(1)在研究对象上,与单纯地面源污染研究不同,集中讨论“农业发展中”因农用化学品施用引起的面源污染,让研究对象更具体,对问题的分析更深入,也使相关的政策建议更具针对性;(2)在研究思路上,尝试将农业发展中的面源污染问题放在城乡二元结构转换的背景下加以研究,并构建一个集宏观、微观与制度层面分析面源污染的基本框架,为面源污染控制与治理的政策体系提供了理论支撑;(3)在研究内容上,理论分析与实证检验紧密结合在一起,阐述并验证了农业结构调整的环境效应,评价了农户的农用化学品投入行为,识别了影响农户施用农用化学品的影响因素,分析了农户农用化学品投入行为的制度原因,形成一个较全面的解释体系;(4)在研究方法上,综合运用宏观与微观、定性与定量、归纳与演绎等分析方法,严谨审慎地把握研究对象在城乡二元结构转换时期的发展现状与发展态势,尽量使研究结论的可靠性有方法论上的支撑。更多还原

【Abstract】 In Chinese rural areas,one of the greatest environmental challenges caused by using agrochemicals(fertilizers and pesticides)in large quantities is non-point pollution,which has a negative impact on people’s health and the sustainable development of rural areas.As part of the national physical sciences fund project,called "Research on the Evolvement of the Rural Settlement System and the Optimization of the Rural Inhabitable Environment in Jianghan Plain(40671050)", this dissertation aims to research into,non-point pollution in the process of the urban-rural dual structure transformation.Firstly,it analyzes the formation of non-point pollution in the process of the city-rural dualistic structure transformation from the macro level,the micro level and the institutional level.Secondly,it attempts to establish a framework for the analysis of non-point pollution.Thirdly,it tries to put forward some suggestions on how to control non-point pollution at low costs.The dissertation argues that non-point pollution in the process of the urban-rural dual structure transformation is mainly caused by structural adjustment of agriculture,behavior of farm households and institution.The dissertation is divided into five parts,namely seven chapters.The first part is Chapter One—Introduction,which aims to introduce the topic and the way of research.It outlines the structure,content and research method of the dissertation,and also briefly explains the innovations and limitations of the dissertation.The second part consists of Chapter Two and Chapter Three,which is a macro-level study on the effects of structural adjustment of agriculture on the environment.Chapter Two expounds the correlation between agricultural production and the environment.On the one hand,as a land-using activity,agriculture influences the environment to a large extent;on the other hand,agriculture also depends on the environment.In the process of the urban-rural dual structure transformation,structural adjustment of agriculture gives impetus to agricultural development.However,structural adjustment and element substitution has also led to rapid increase in the amount of application of agrochemicals in the past three decades.As a result,non-point pollution has become more serious.Chapter Three is theoretical explanation of effects of structural adjustment of agriculture on the environment and empirical verification it with chronological data.The dissertation constructs a model which shows the effects of structural adjustment of agriculture on the environment.The model makes it clear that the effects can be positive or negative,with structural adjustment as the determining factor. A regional analysis of structural adjustment and changes in agricultural input demonstrates that the input of fertilizers and pesticides is on the rise in most regions.The model of agricultural development in many regions is turning quickly from depending on traditional input to depending on capital input. The "high input,high yield,high emission" pattern of agricultural development has come into being. This hypothesis is substantiated through co-integration analyses and Grange Causality Test.The third part consists of Chapter Four and Chapter Five,which is a micro-level study on the agrochemical input behavior of farm households.Structural adjustment of agriculture in essence results from behavior of farm households.Chapter Four is an empirical research on the input of fertilizers by farm households.The output elasticity of fertilizers is only 0.1 on average,and excessive fertilizers are used in farming.There are three main factors affecting the application of fertilizers: working population in farm households,level of urbanization and average net income.The empirical research shows that with the population keeps increasing,most farm households still choose to use more fertilizers to guarantee the yield,but they no longer use organic fertilizers to preserve the productivity of the land.The reason for this is that the urbanization process has changed the opportunity cost of farmers’ labor.Chapter Five studies the input of pesticides by farm households.An empirical study on the use of pesticides on three crops(corn,wheat and late rice)shows that the output elasticity of pesticides is as low as below 0.1,which means rural households tend to increase the input of pesticides despite the small marginal output.The use of pesticides is determined by many factors,such as land per household,revenue,prices of pesticides,working population in farm households,and non-cereal crop ratio.The micro-level analysis of the agrochemical input behavior of farm households concludes that the input of both fertilizers and pesticides is far from optimal and it results in non-point pollution.The fourth part is Chapter Six,which analyzes the behavior of farm households from an institutional standpoint.There is an institutional reason for the wide use of agrochemicals in China. The absence of property rights to farmland has encouraged a preference for short-term profit.Since farm households value land use rather than land maintenance,input which brings profit in the short run rather than input which brings profit in the long run,using agrochemicals in large quantities has become a possibility.Besides,other institutional problems which encourage the production and distribution of agrochemicals have made matters worse,turning the "possibility" into a "reality."The fifth part is Chapter Seven—Conclusion.The dissertation argues that in order to control non-point pollution,transforming incentive factors should play a leading role,adjusting the behavior of farm households should be given priority,and non-point pollution in intensive farming areas should be dealt with first.An integrated non-point pollution control system which combines legal,economic and administrative means should be established.To reduce the environmental cost agricultural production,it is necessary to strike a balance between the benefits and costs of a policy. Fundamentally speaking,the right way to develop agriculture is to control non-point pollution and develop a resource-saving and environment-friendly pattern.The innovations of the dissertation can be summed up in four points.First,the research object is specific.The dissertation focuses on non-point pollution caused by using agrochemicals in "agricultural development." Therefore,the analysis of the problem is more insightful and the suggestions more pertinent.Second,the dissertation tries to study non-point pollution in agricultural development against the background of urban-rural dual structure transformation,and construct an analytical framework that incorporates the macro level,micro level and institutional level,which provides theoretical support to the control of non-point pollution.Third,the dissertation combines theoretical analysis with empirical verification.It elaborates and validates the effects of structural adjustment of agriculture on the environment,evaluates the agrochemical input behavior of rural households,identifies the factors affecting the use of agrochemicals by farm households,and analyzes the institutional reasons for the use of agrochemicals.Last but not least,the dissertation uses many kinds of research methods,both macro and micro,qualitative and quantitative,inductive and deductive.It refers to the research results of many other disciplines and tries to provide methodological support to the conclusions of the study.更多还原