淮河流域化肥施用空间特征及环境风险分析  

Distribution and Environmental Risk Assessment of Fertilizer Application on Farmland in Huai River Basin

作　　者：刘钦普[1] 

机构地区：[1]南京晓庄学院环境科学学院,江苏南京211171

出　　处：《生态环境学报》2015年第9期1512-1518,共7页Ecology and Environmental Sciences

基　　金：国家自然科学基金项目(41201151);江苏省生态学重点建设学科项目;南京市环境科学重点建设学科项目

摘　　要：深入认识淮河流域化肥施用环境风险,对提高化肥施用风险意识、加强风险管理、防治农业面源污染有着重要作用。综合考虑化肥施用强度、效率、环境安全阈值、环境影响效应及作物复种指数等5种因素,构建了化肥施用农田污染环境风险评价指数模型,对淮河流域化肥施用空间特征和环境风险进行研究。应用层次分析法,确定氮磷钾三因子对环境影响的权重系数。根据国家环境保护部2010年设定的生态乡镇建设化肥使用强度单位播种面积小于250 kg·hm-2的标准,按照氮磷钾1∶0.5∶0.5的比例,确定氮磷钾三因子的环境安全阈值。在不考虑氮磷钾单质化肥环境影响效应权重的情况下,以作物复种指数为1、化肥利用率为50%为基准,建立化肥环境风险评价等级标准。结果表明,淮河流域化肥施用强度最高的地市是淮南市,为1 242.2 kg·hm-2,是强度最低的淄博市478.7 kg·hm-2的2.6倍。淮河流域平均化肥施用强度为776.6 kg·hm-2,是我国生态乡镇建设化肥施用标准的3.1倍。化肥施用强度分布有一定的规律性,大致沿着偏东北西南走向有4个带状分布区,高过量施肥区和中过量施肥区从南到北依次交替出现。淮河流域化肥施用环境风险总指数是0.74,属于中等程度风险,处于Ⅱ级预警。35个地市化肥污染风险预警级在Ⅰ和Ⅳ之间,分别呈连片状聚集分布。单质肥料氮磷钾风险指数分别是0.74、0.81和0.64,分别属于中度风险、严重风险和轻度风险,处于Ⅱ、Ⅳ、Ⅰ级预警。总的来看,淮河流域过量的化肥施用普遍存在较为严重的中等环境风险,已经对流域的生态环境产生了较为严重的影响。Soil pollution by fertilization has become one key cause of water pollution in watershed. Environmental risk assessment of fertilization in Huai River basin were made in order to fully recognize the intensity of agricultural fertilization and its potential threats to the ecological environment, strengthen environmental risk awareness and control agricultural non-point pollution. Model of fertilization environmental risk assessment was established by introducing such five factors as fertilization intensity, fertilization environmental safety threshold, fertilization environmental effect weight, multi-cropping index (MCI) and fertilization efficiency. Analystic hierarchy process (AHP) was used to determine the weights of N, P, K. The environmental safety thresholds of N, P, K was made according to the standard of 250 kg·hm-2, the total fertilizers mass per sowing cropland, which is for the construction of ecological villages and town sponsored by Chinese government,and the proportion of 1∶0.5∶0.5 for N∶P∶K. The standard of classification for the fertilization environmental risk was made on such conditions as the equal impacts on the environment for the single fertilizers, 1 MCI and the ratio of 50%for fertilizer efficiency. Results showed that, at present the rate of farmland fertilizer in Huai River basin is 776.6 kg·hm-2, which is as 3.1 times as the standard of 250 kg·hm-2 with the regional difference from the maximum of 1 242.2 kg·hm-2 to the minimum of 478.7 kg·hm-2. The distribution of fertilization intensity showed four east-west strips from south to north with alternation of high overuse fertilization trip to medium overuse fertilization. The fertilization environmental risk index of Huai River was 0.74, belong to medium degree risk, at Ⅱ warning grade. The warning grades for 35 regions in this basin ranged from Ⅰ to Ⅳ with clustering distribution. The risk indexes for nitrogen, phosphorus and potash were 0.74, 0.81, 0.64, respectively, each being at Ⅱ, Ⅳ, and Ⅰ warning grade. The o

关 键 词：化肥施用强度 环境风险评价 环境安全阈值 模型构建 预警 淮河流域 

分 类 号：X53[环境科学与工程—环境工程]