【作者】 杜江；

【导师】 王雅鹏；

【作者基本信息】 华中农业大学 ， 农业经济管理， 2009， 博士

【摘要】 改革开放以来,中国的农业与农村经济发展取得了长足的进步,农民人均收入稳定增长,主要农产品产量和人均占有量大幅提高。在自然资源禀赋并不十分理想的条件下,中国主要依靠自己的力量解决了13亿人的吃饭问题,从而有力地回答了“谁来养活中国”的质疑。但是,中国的农业与农村经济发展在很大程度上是以牺牲资源与生态环境基础为代价。中国在持续地保证农产品充分供给的同时,却面临着生态环境日益恶化的威胁。近些年来,伴随着农业现代化进程的不断推进,区域化、集约化和专业化的逐步推进进一步加大了农业对环境的污染,给农业可持续发展带来了严峻的挑战。新时期,资源和环境的双重约束已经成为制约中国农业发展的“瓶颈”,探寻农业增长与发展新的突破口,并实现农业与环境的协调发展已成为目前所要迫切解决的问题。论文以中国的经济转型期为背景,以农业经济学、发展经济学、资源与环境经济学的相关原理以及人力资本理论等为研究基础,采取理论分析与实证分析相结合的方法,对中国的农业增长与环境污染问题进行了研究。第一,根据人力资本理论将农户人力资本投资划分为教育投资、迁移投资和健康投资,并基于包含人力资本的经济增长模型,加入其他的控制变量,利用省级面板数据实证估计各因素对农业经济增长的贡献,以找到农业经济增长的源泉。第二,分析农业生产中化学投入品对农产品增产、农业增值的作用,并进一步论述化学品使用对环境造成的污染,由此指明农业污染问题不可忽视。第三,以环境库兹涅茨曲线(EKC)理论及其实证研究范式为基础,定量分析农业增长与环境污染之间的关系,以判断目前我国农业污染所处的阶段。具体包括:①运用传统的简约式EKC估计模型及其扩展式,定量分析农业增长与化学品使用之间的宏观趋势;②运用结构式估计模型,估计农业增长对环境污染的规模效应、结构效应和技术效应。第四,主要从宏观层面的农业部门、社会与政府角度来分析农业污染形成的原因。论文的主要结论如下:(1)改革开放以来,农户越来越重视对人力资本投资。农户人力资本投资的增长幅度高于收入增长幅度,对人力资本投资已是他们日常生活支出的重要组成部分。但投资力度受到收入增长缓慢等因素的影响,未来农户人力资本投资潜力巨大。(2)传统要素和人力资本均是农业增长的驱动因素,其他因素的影响各不相同。物质资本、土地和化肥投入是农业增长的源泉,其中土地是重要源泉。教育投资对农业增长促进作用最大,其次是迁移投资,健康投资对农业增长的贡献不明显。经济结构、城市化、对外贸易、财政支农、政府的经济活动参与度、国有化程度等因素均对农业增长产生了不同影响。(3)化学投入品对农业增长作出了重要贡献,但化学品的不正确使用甚至滥用则会对环境产生污染,严重时还会对人类的生命健康构成威胁。农业污染问题不可忽视。(4)简约式和结构式模型估计结果均说明,环境污染状况随着农业的增长进一步恶化。简约式模型估计结果显示,化肥、农药、农膜的使用处于EKC左半段,三要素的投入密度随着农业增长而进一步提高,环境污染状况进一步恶化。结构式模型显示,农业增长对环境的规模效应为负(伴随着农业增长和规模扩大,化学品使用密度提高),技术效应为正(伴随着农业技术进步,化学品施用密度降低),结构效应因化学品的不同而不同。目前农业增长对环境的规模效应占居主导地位,伴随农业增长,环境污染状况进一步恶化。简约式和结构式模型估计结果一致。(5)微观层面的农户在化学品使用选择上主要受利益的驱动,化学品使用所可能引起的污染并不是他们关心的主要问题。农业发展过程中,农业部门的结构变动和农业生产中投入要素的替代是化学品使用增加的原因之一,但结构变动和要素替代是传统农业向现代农业转变过程中所表现出的主要特征之一。对农业污染形成原因的分析还需从社会与政府层面入手,具体包括以下几个方面的成因:粮食安全保障与产业政策、区域性贫困、城乡分割的二元结构、农业技术推广体系不健全、农业污染控制资金投入不足、缺乏对流域的综合管理、环境污染管理体制的冲突、农业与环境政策的脱离、农业污染治理法律缺失、环境教育不足。论文的可能创新有以下三点:(1)在一个统一的框架内分析了农业增长与环境污染之间的关系。以往有关农业增长与农业污染的研究比较零散,或者局限于探讨农业经济增长的驱动因素,或者主要分析农业污染产生的方式和原因。本文则在一个统一的框架内分析了两者之间的关系。第一,利用近期数据定量分析农业增长的源泉,发现我国仍然处于传统农业阶段,对化肥、土地的依赖程度非常高。第二,在肯定农业化学品使用的重要贡献的同时,指出不能忽视化学品使用所带来的污染问题,并进一步对农业增长和环境污染之间的关系进行了宏观经济分析,以判断目前我国农业污染所处的阶段。在农业增长与环境污染两者的结合研究方面做了一个尝试,这也可以说是研究视角的创新。(2)以主流经济学理论及其实证研究范式为基础,定量分析农业增长与环境污染之间的关系。第一,根据人力资本理论,将农户人力资本投资划分为教育投资、迁移投资和健康投资,利用包含人力资本的经济增长模型,并加入其他控制变量,实证分析农业经济增长的源泉。第二,将EKC研究理论与实证方法应用到农业领域,利用简约式的估计模型分析农业增长与化学品投入的关系,并且进一步利用经过改进的结构式EKC模型,分析农业增长对环境污染的规模效应、结构效应和技术效应。通过以上两类模型的估计来判断目前我国农业污染所处的阶段。这可以说在实证方法应用方面有所创新。(3)通过理论和实证分析得出了一系列有价值的结论:“农户日益重视对人力资本投资,其中教育投资始终放在首位,迁移投资力度越来越大,健康投资的重视程度相对较低,但健康需求潜力巨大;教育投资对农业增长促进作用最大,其次是迁移投资,健康投资的贡献不明显;城市化、对外贸易、财政支农、非国有化、政府经济活动参与度等对农业增长产生了不同影响;城乡收入差距的降低有助于降低化学品使用的强度从而降低农业对环境的污染程度”等。根据分析结果,取得了有价值的政策含义并提出了可操作的对策建议,这对于进一步认识农业增长与环境之间的关系具有重要的理论和实践指导价值。更多还原

【Abstract】 Since the economic reform and opening-up, the development of China’s agriculture and rural economy has being making substantial progress. Peasant’s income per capita increases steadily, and total output and possession per capita of agricultural product increase greatly. Under the conditions of natural resource endowment that is not ideal, China has answered the question of "Who will feed China?" powerfully by successfully handling the food problem faced by 13 hundred million people mostly by himself. However, development of China’s agriculture and rural economic proceed mostly at the cost of sacrificing the base of natural resources and environment. While continuously ensuring sufficient supply of agricultural product, China is facing the threat of deterioration of the natural environment day after day. Recently, in the process of agricultural modernization, environmental pollution made by agriculture has been aggravated by the regionalization, intensiveness and specialization of agricultural development. This brings about big challenge to agricultural sustainable development. Now, constraints of natural resource and environment have being the bottleneck to agricultural development, find a new way to the growth and development of agriculture, and make reality the harmonizing development of agriculture and environment are our high priority.On the background of economic transition in China, based on related principles of agricultural economics, development economics, natural resource and environmental economics, and human capital theory, with the method of theoretical and empirical analysis, this dissertation studies the relationship between agricultural growth and environmental pollution in China. Firstly, in line with the human capital theory, farmer’s investment in human capital is divided into three categories: investment in education, investment in transfer and investment in health. Based on economic growth model including human capital and by adding other controlled variables, using regional panel data, this dissertation makes empirical analysis about the driving factors influencing agricultural economic growth, so that sources of agricultural growth can be identified. Secondly, this dissertation studies the contribution role that chemical inputs make to the increase of agricultural total output and value. Furthermore, environmental pollution caused by use of chemical inputs is analyzed. One point is to be clear that agricultural pollution will never be overlooked. Thirdly, according to Environmental Kuznets Curve hypothesis, empirical study is carried out on relationship between agricultural growth and environmental pollution to find out in which stage China’s agricultural pollution is at present. Two further steps are adopted: the first step is to quantitatively study the macro-trend between agricultural growth and application of chemical inputs using traditional reduced form of EKC model and its extension types; the second step is to estimate the scale effect, composition effect and technique effect made by agricultural growth to environmental pollution using revisited structural model based on EKC models. Fourthly, reasons of agricultural pollution are given from angles of agricultural sector, society and government. The main results are as follows:Firstly, since the economic reform and opening-up, farmer has more and more attached importance to the investment in human capital. For farmers, invest in human capital is becoming an important part in their usual spending, because increase rate of investment is higher than income per capital. However, investment in human capital is hampered due to influences coming from slow improvement of personal income etc. Invest in human capital in future is potentially huge.Secondly, traditional factors and human capital are driven factors to agricultural economic growth and other factors have different influences. Physical capital, land and fertilizer input are the sources of agricultural growth, and land is the most important one. Education makes the biggest contribution to agricultural growth, and then is the investment in transfer, and contribution of investing in health is not significant. Others factors, such as economic structure, urbanization, foreign trade, agricultural financial support, government’s involvement in economic activity, etc., make different impacts.Thirdly, chemical inputs have made great contribution to agricultural growth. But improper use or even abuse use of chemicals will give rise to environmental pollution. It may be great threat to human’s survival. Agricultural pollution should never be overlooked.Fourthly, results of reduced and structural form of estimation model implied that environmental pollution will be even worse in the process of agricultural economic growth. Results from reduced form of model indicate that, use of fertilizer, pesticide and plastics are in the left part of EKC, intensity of all three inputs will increase as agricultural growth, which implies that environmental situation will be deteriorated. Results from structural form of model indicate that, scale effect of agricultural growth to environment is negative (as agricultural growth and scale is growing, intensity of chemical input will increase), technique effect is positive (as agricultural technique improves, intensity of chemical input will decrease), composition effect has different influence due to different chemicals. At present, the scale effect is the overwhelming factor; therefore, agricultural growth is accompanied by environmental deterioration. Consistent results are obtained using different models.Fifthly, from the micro-level, the driving force determining farms’ choice of chemical input is the benefit, and environmental pollution caused by chemical application is not their primary concern. During the process of agricultural development, structural change of agricultural sector and inputs replacement in agricultural production are reasons of increasing use of chemical inputs. However, structural change and input replacement are exactly the main characteristics of involving process of traditional agricultural to modern agriculture. Therefore, deep reasons causing agricultural pollution is to be found from the macro-level of society and government. Specifically, analysis could be progressed as follows: food security guarantee and industrial policies, regional poverty, dual structural of urban-rural break-up, deficient system of agricultural technology diffusion, inadequate funds of agricultural pollution control, insufficient valley integrated management, conflicts of environmental pollution management system, separate of agricultural and environmental policies, lack of containment law of agricultural pollution and insufficient environmental education.The possible innovative points of this dissertation are as follows:Firstly, study is implemented on the relationship between agricultural growth and environmental pollution in a systematic frame work. Early studies have made scattered research: focus only on the driving factors to agricultural growth, or focus only on the ways and reasons of agricultural pollution. In this framework, study is made on the relationship between agricultural growth and environmental pollution systematically. To do so, two further steps are carried out. The first step, use recent panel data, empirical study is given to identify the sources of agricultural economic growth, and find out that China’s agriculture is still in the traditional stage, characterized by high dependence on chemical inputs and land. The second step, by confirming great contribution that agricultural chemical inputs have made to agriculture, it points out that environmental pollution caused by chemical inputs should not be overlooked. Then, further analysis is given on relationship between agricultural growth and environmental pollution by empirical study so that we can know the stage that agricultural pollution is in. An integrated analysis relating agricultural growth to environmental pollution is attempted in the present study, which is also innovative in a manner of research perspective. Secondly, on the basis of main stream economic theory, quantitative analysis is implemented on the relationship between agricultural growth and environmental pollution. To do so, two further steps are required. The first step, according to related research, human capital investment by farmer is divided into investment in education, investment in transfer and investment in health. Then, based on economic growth model including human capital, empirical study is carried out to find out the sources of agricultural economic growth. The second step, with the application of EKC theory and its estimation method to agriculture field, study on the relationship between agricultural growth and chemical inputs is mad by using reduced form of estimation model. Moreover, revisited structural form of EKC estimation model is used to study the scale, composition and technique effect that agricultural growth makes to environmental pollution. After these two types of estimation are implemented, the stage in which China’s agricultural pollution is in at present could be identified. Therefore, the second innovative point is also innovation on the application of empirical research method.Thirdly, a series of valuable conclusions have been obtained. A series of conclusions have been obtained based on theoretical and empirical study systematically: farmers value investment in human capital day after day, and investment in education is the most important one, investment in transfer is becoming more and more important, investment in health is relatively low, but has great potential; investment in education makes the greatest contribution to agricultural growth, investment in transfer makes the second best, the contribution made by investment in health in insignificant; urbanization, agricultural financial support, non-nationalization, government’s involvement in economic activity, etc., have different impacts on agricultural growth; decrease of urban-rural income gap can be contributable to the decrease us chemical inputs and therefore helpful to the alleviation of pollution made by agriculture to environment, etc. According to estimation results, valuable policy implication is obtained and applicable measures are put forward, which will give theoretical and practical guiding to the further understanding of the relationship between agricultural growth and environment.更多还原