中国农业面源污染排放格局的时空特征

SPATIAL-TEMPORAL VARIATIONS OF AGRICULTURAL NON-POINT SOURCE POLLUTION IN CHINA

[目的]农业面源污染排放量在不同作物间的分配格局变化的信息对于国家制定农业面源污染防控政策具有重要的意义,不同作物生产的污染排放格局及其形成原因亟待深入分析。[方法]文章在测算各类作物生产中农业面源污染排放量的基础上,定性与定量相结合研究我国农业面源污染及其内在构成的时空差异。[结果](1) 1998—2014年,我国农业面源污染排放总体呈下降趋势,农业面源污染排放格局已从谷物作物转向蔬菜作物。(2)我国农业面源污染排放空间差异明显,面源污染排放高的省份集中于黄淮海平原,低值省份则主要分布于我国的西部地区,农业面源污染增长主要集中在西北地区。(3)东北地区谷物作物面源污染排放比重高,东南沿海地区蔬菜作物面源污染排放比重高。(4)污染排放强度对谷物作物面源污染排放的影响较大,而蔬菜作物面源污染排放的增加则主要归因于种植面积的扩大。[结论]应因地制宜地制定农业发展政策,科学调整农业种植结构,改造传统农业向技术密集型现代农业转变。

Current issues suggest that distribution pattern of agricultural non-point source pollution among different crops is of great significance,and that accurate information will play a major part in the formulation of national pollution prevention policy. However,spatial distribution pattern of agricultural pollution and its specific cause between different crops have not been further studied. Based on the estimation of agricultural non-point source pollution produced by different crops,the temporal and spatial variations of agricultural non-point source pollution were studied by combination of qualitative and quantitative methods from the perspective of provincial plantation structure. Results showed that (1) A decreasing trend was discovered in agricultural non-point source pollution from1998 to 2014. Meanwhile,the amount of agricultural non-point source pollution had been reduced from cereal crops to vegetable crops.(2) The spatial differences of agricultural non-point source pollution were obvious in China.Provinces with heavier pollution were mainly located in Huang-Huai-Hai Plain,while the less polluted provinces were concentrated in western areas. The increase of agricultural non-point source pollution in northwest was larger than other regions.(3) The proportion of pollution from cereal crops in northeast was higher than other regions,compared with that the proportion of pollution from vegetable crops was larger in eastern coastal regions.(4) The increase of pollution in cereal crops was attributable to the intensity of pollution,while the increase of vegetable crops was largely due to the enlarging sown area. It is necessary to formulate agricultural development policies according to local conditions,as well as scientifically adjust the structure of agricultural cultivation,and transform traditional agriculture into technology-intensive modern agriculture.