The Causes And Negative Externality Of Agricultural Chemical Fertilizer Pollution In China

As the "grain" of grain,chemical fertilizer is an important agricultural production material,which plays an irreplaceable role in promoting food production and ensuring food security.In recent years,there are many problems in the application of chemical fertilizers in China,for example,the high amount of fertilizer applied per mu,the unbalance input quantity of fertilizer between regions or crops,the unreasonable input structure of fertilizer,and the unscientific methods of use,etc.These problems have caused a lot of non-point source pollution,and have brought serious negative externality on the agricultural production environment.For example,a lot of field trials and related studies show that non-point source pollution caused by chemical fertilizers has destroied the soil microorganism diversity and soil structure,as well as causing serious water pollution,etc.Once used in agricultural production,these contaminated soil and water resources are bound to cause serious damage to agricultural production.So,in addition to damaging the agricultural production environment,the fertilizer pollution may further threaten the agricultural performance in our country and thus have an effect of negative externality in food production.Therefore,under the background of increasingly serious fertilizer pollution in China,analyze the influence factors of fertilizer pollution,and evaluate the possible negative externality of fertilizer pollution on agricultural environment or agricultural production,will have important theoretical and practical significance.Based on the view of Social-Ecological Systems(SESs),the agricultural production system is essentially a complex and hierarchical social ecological system,which is a system of mutual restriction and multi-scale interaction of various factors,and its ecological and environmental problems are related to many factors such as natural,economic and social factors.Therefore,only view non-point source pollution caused by chemical fertilizers from the perspective of complex systems,can we possible to dig deeply into the critical social and economic factors which may affect the fertilizer pollution,and can we fully clarify the possible negative effects of fertilizer pollution in complex systems,thus some valuable guidance can be provided to clarify the cause and consequence of fertilizer pollution.Based on the analysis above,this paper puts forward a systematic analysis framework which is about the study of fertilizer pollution based on the theory of SESs,and this study is mainly focus on three aspects:What are the influence factors of fertilizer pollution?What is the negative externality of fertilizer pollution on water resources or food production,more specifically,what is the adverse impact of fertilizer pollution on water resources?Is there the"environmental punishment" effect of fertilizer pollution on food production?On the basis of comprehensive and systematic review of relevant research findings at home and abroad,this paper studies the causes and negative externalities of fertilizer pollution.Firstly,analyze the influence factors of fertilizer pollution.We fully integrate social and economic factors,such as price distortion and non-agricultural employment,into the analysis framework of the influence factors of fertilizer pollution,and then build a dynamic panel system GMM model to estimate the influence factors empirically.Secondly,study the negative externality of fertilizer pollution on water resources based on two perspectives of water resource utilization and water environment pressure.We use the grey water footprint model to calculate the relative indexes of grey water footprint caused by fertilizer pollution,and then further evaluate the effect and ecological appropriation of fertilizer pollution on water resources.Meanwhile,we construct the index of water environment pressure under the multi-year average run-off situation,and further evaluate the condition of water environment pressure caused by fertilizer pollution.Thirdly,study the negative externality of fertilizer pollution on food production based on the hypothesis of"environmental punishment".On the basis of theoretical analysis of the formation mechanism of "environmental punishmen" effect,we further estimate the marginal contribution and its variation characteristics of fertilizer to food production,so it provides a realistic basis for verifying the "environmental punishment" effect.Based on the analysis above,we empirically estimate the "environmental punishment" effect of pollution on food production by using the dynamic panel GMM model from the aspect of environmental efficiency.Finally,we summarize main research conclusions and put forward corresponding policy suggestions.The main conclusions of this paper are as follows:Firstly,the influence factors of non-point source pollution caused by chemical fertilizers.The price distortion of fertilizer has a significant positive effect on promoting the discharge of fertilizer pollution,in other words,the higher the price distortion,the higher the pollution degree of fertilizer pollution.Non-agricultural employment also has a significant positive effect on promoting the discharge of fertilizer pollution,that is to say,the more non-farm payrolls are accompanied by more serious pollution levels,and to some extent the conclusion confirms the hypothesis of factor substitution which is mentioned in this paper,showing that increasing non-agricultural employment will promote the fertilizer consumption.In addition,enhancing the planting proportion of grain,and implementing the policies about pollution control can effectively reduce the fertilizer pollution,and technological progress aggravates the pollution to some extent.Secondly,the negative externality of non-point source pollution caused by chemical fertilizers on water resources.The fertilizer pollution has caused serious negative externality on water resources in the process of food production:From the perspective of water resource utilization,the fertilizer pollution has caused serious pollution and ecological occupation to water resources,and the water resources quantity which is needed to dilute the fertilizer pollution to the required freshwater standards is showing an increasing trend,therefore this will severely challenge the quantity and quality of water resources.Besides,from the perspective of water environment pressure,the fertilizer pollution has caused different water pressure conditions in various provinces and regions,and the water environment pressure is showing an upward trend overall.Thirdly,the negative externality of non-point source pollution caused by chemical fertilizers on food production.The fertilizer pollution has significant effect of negative externality on food production,and the empirical results show that fertilizer pollution has a significant negative effect on the environmental efficiency of wheat,maize and rice.Therefore,these results explain the possible correlation between fertilizer pollution and the declining marginal contribution of fertilizer to food production to a certain extent,and reveal the negative feedback of fertilizer pollution on food production from one aspect.The possible innovations of this paper are mainly manifested in the following aspects:Firstly,it is the research idea.Previous research which is relataed to the fertilizer pollution is less based on systematic thought.This paper use SESs as the theoretical guidance,and study the problem of fertilizer pollution based on the systematic perspective.This line of thinking can not only fully take into account the possible influence of human behavior and socio-economic factors for the analysis of the influence factors of fertilizer pollution,but also can fully take into account the negative externality caused by fertilizer pollution,and thus can fully take into account the interaction between the complex systems of agricultural production.Therefore,there is some innovation in research idea.Secondly,it is the selection of the influence factors of fertilizer pollution.Previous research which is relataed to the influence factors of fertilizer pollution has not taken into account some policy consequences and social development trend comprehensively.Based on this,this paper incorporates two important factors including the price distortion of fertilizer and non-agricultural employment into the analysis of influence factors by digging deep into the socio-economic factors that may affect the fertilizer pollution.This analysis process can further deepen the understanding of the root cause of agricultural pollution.Therefore,there is some innovation in the perspective of research.Thirdly,it is the evaluation method of water pollution.Previous research which is about the evaluation of water pollution is rarely based on the water footprint perspective.This paper uses the grey water footprint method to evaluate the ecological footprint and water environmental pressure caused by fertilizer pollution.This can directly reflect the impact of fertilizer pollution on water resources through the relationship between regional water quality and water quantity,and this can further extend the evaluation methodology of water resources pollution.Therefore,there is some innovation in the research method.Fourthly,it is the research on the "environmental punishment" effect.Previous research usually regards fertilizer pollution as the outcome variable of agricultural production process,and it is rare to test the possible negative feedback effects of fertilizer pollution on food production.This paper regards the fertilizer pollution as the cause variable of agricultural production process base on the thought of system thinking,and empirically estimates the possible "environmental punishment" effect of fertilizer pollution on food production.The study of the "environmental punishment"effect can reveal the inner mechanism about the declining marginal contribution of fertilizer to food production to a certain extent,and then can provide a novel research perspective for the study of the potential links between agricultural non-point source pollution and agricultural production.Therefore,there is some theoretical innovation in this paper.