| 摘要: |
| 【目的】明确陕西省化肥施用现状，科学评价化肥施用环境风险，为该区域农业面源污染防控提供参考。【方法】基于陕西省1987-2016年30年化肥施用相关统计数据，分析了该省化肥施用时空分异特点，并采用相关分析模型对其化肥施用面源污染环境风险进行评价。【结果】1987-2013年陕西省化肥施用量、施用强度整体呈现递增趋势，而2013年之后全省化肥施用量、施用强度稳中有降。1987-2016年氮肥比例呈下降趋势，而磷肥和钾肥比例稳步提高，氮磷钾施用比例由1987年的1∶0.20∶0.06逐步调整为2016年的1∶0.41∶0.46。2016年陕西省化肥施用强度达799.48 kg/hm2，属于高度过量水平；陕西省化肥施用强度空间分异明显，其中关中化肥施用强度最高，陕南次之，陕北最低。2016年陕西省总肥施用风险指数为0.76，化肥施用风险总体属于重度风险等级，其中关中风险最大，陕南次之，陕北最小。【结论】陕西省化肥施用强度高，面源污染环境风险大，且不同区域空间分异明显。在确保作物产量的基础上，为有效实施面源污染环境风险管控，陕北可基本维持现有施肥强度，但在施肥结构上应注意减氮增磷补钾；关中应以降低化肥施用强度为抓手，在减肥的基础上注意稳氮提磷减钾；陕南应在降低化肥施用强度基础上继续优化施肥结构，注意减氮增磷补钾。 |
| 关键词: 化肥施用强度 面源污染 环境风险 时空分异 陕西省 |
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| 基金项目:陕西省重点研发计划项目“秸秆资源在农田土壤的综合利用技术开发与示范”（2018ZDCXL-N-19-1）；陕西省创新能力支撑计划项目“苹果枝条资源化利用关键技术集成与示范”（S2019-ZC-XY-0003） |
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| Spatio temporal differentiation and non-point source pollution environmental risk assessment of fertilization in Shaanxi |
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GAO Ying,SUN Xijun,Lu Shuang,et al
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| Abstract: |
| 【Objective】This study clarified the status of fertilizers application and evaluated its environmental risk to improve the control of agricultural non point pollution in Shaanxi Province.【Method】Based on statistical data of fertilizers application in Shaanxi from 1987 to 2016,this study analyzed the characteristics of spatio-temporal differentiation of fertilizers application and used correlation model to evaluate the environmental risk of non point source pollution of fertilizers application.【Result】From 1987 to 2013,fertilizers amount and fertilization intensity in Shaanxi showed an overall increasing trend,while they decreased steadily after 2013.From 1987 to 2016,the rate of nitrogen (N) fertilizer showed a downward trend,while the rates of phosphorus (P) and potassium (K) fertilizers increased steadily.The application ratio of N fertilizer,P fertilizer and K fertilizer was gradually adjusted from 1∶0.20∶0.06 in 1987 to 1∶0.41∶0.46 in 2016.In 2016,the application intensity of fertilizers in Shaanxi reached 799.48 kg/hm2 at a highly excess level.The application intensities of fertilizers in different cities showed clear spatial differentiation characteristics with a decreasing order in Guanzhong,South Shaanxi and Northern Shaanxi.In 2016,the risk index of total fertilizer application in the whole province was 0.76 at the serious risk level.The highest risk was in Guanzhong,followed by Southern Shaanxi and North Shaanxi.【Conclusion】The fertilization intensity and environmental risk of non point source pollution in Shaanxi were both high with clear spatial differentiation.On the basis of ensuring crop yield,to effectively control the environmental risk of non point source pollution,existing fertilization intensity can be basically maintained in Northern Shaanxi,while attention should be paid to reducing N, increasing P and supplementing K in fertilization structure.The key point of Guanzhong is to reduce fertilization intensity while stabilizing N,increasing P and reducing K.For Southern Shaanxi,fertilization structure should be continuously optimized and more attention should be paid to reducing N, increasing P and supplementing K. |
| Key words: fertilization intensity non point source pollution environmental risk spatio-temporal differentiation Shaanxi |
