湖北省2008~2017年人类活动净氮输入状况

Net anthropogenic nitrogen accumulation in Hubei province from 2008 to 2017

为探究湖北省人类净氮输入状况,本文基于湖北省14个地级市(省直辖县)行政单元统计数据,利用人类活动净氮输入(NANI)模型,核算湖北省2008~2017年的人类活动净氮输入量.结果表明,湖北省10a平均NANI值为15929.43kg/(km^2·a).湖北总NANI值随时间呈现出先增长后下降的趋势,其中2013年达到16959.93kg/(km^2·a).在空间分布上,湖北省中东部地区(襄阳、荆门、荆州、随州、孝感、武汉、鄂州、黄冈、省直辖县)的NANI值显著高于西部地区(十堰、宜昌、恩施自治州);氮源结构上,氮肥输入(年均贡献比例60.58%)是最大输入项,其次分别为食品/饲料净氮输入(24.85%)、生物固氮(8.16%)、大气氮沉降(6.25%)和种子氮输入(0.18%).因此,减少化肥投入,提高农业产出投入比,同时合理控制人口密度,是减少区域内净氮负荷量,降低氮素污染的有效措施.

In order to explore the net anthropogenic nitrogen inputs in Hubei Province,the net anthropogenic nitrogen inputs(NANI)model was applied to calculate the net nitrogen input in Hubei from 2008 to 2017 based on the statistical data of 14 prefectures/counties directly under the jurisdiction of the province.The results showed that the 10-year annual average NANI of Hubei Province was 15929.43 kg/(km^2·a).During the study period,the NANI value increased first and then decreased with a peak of 16959.93 kg/(km^2·a)in 2013.For the spatial distribution,the NANI values in the Middle East of Hubei,i.e.,Xiangyang,Jingmen,Jingzhou,Suizhou,Xiaogan,Wuhan,Ezhou,Huanggang,and counties directly under the jurisdiction of the province,were significantly higher than those in the West,i.e.,Shiyan,Yichang,Enshi Autonomous Prefecture.The largest nitrogen input source was nitrogen fertilizer with an annual contribution percentage of 60.58%,followed by N in human food and animal feed(24.85%),atmospheric N deposition(8.16%),N fixation(6.25%),and seeding N input(0.18%).Therefore,it would be effective to reduce the net nitrogen load and nitrogen pollution in the region by reducing the application of chemical fertilizer,improving agricultural structures and reasonably controlling the population density.