中文摘要：

通过获取2002―2013年湛江地区的自然资源、工业、农业、人口和环保等基本统计数据和相关参数,评估了湛江市辖区氮素的来源去向、收支演变趋势及环境效应。结果显示,氮输入总量在35 444.03~40 466.69 t波动;氮源的贡献为化肥氮、人畜排泄物、大气沉降、作物残体和工业废水,其中化肥氮的贡献率从2006年开始呈降低趋势,2008年之后趋于平稳,这可能与2006年湛江开始实施农田测土配方施肥有关;而工业废水氮的输入量在2010年之后迅速增加,与2009年东海岛工业基地的开工有关。氮输出总量在2002―2006年增长了16.35%,2007年开始降低并趋于稳定。氮负荷较高且与耕地面积比例显著相关。氮盈余量变化较大,2002年为6865.97 t,2013年降低到3 998.96 t,呈减少趋势;年盈余负荷由47.03下降至23.48 kg/hm2。对单位面积施肥量和作物收获氮/施氮量值的分析表明,该地区面临着氮收支不平衡造成的氮污染潜势。

英文摘要：

By using the basic statistical data（natural resources, industry, agriculture, population and environmental protection） and related parameters in Zhanjiang Area during 2002-2013, the Nitrogen budget in Zhanjiang municipal district and its environmental effect were assessed. Results show that total Nitrogen input fluctuated during 35 444.03~40 466.69 t; the Nitrogen source was from fertilizer nitrogen, human and animal excretion, atmospheric settlement, farmland, crop residual body and industrial wastewater, respectively; the contribution of fertilizer Nitrogen was reducing from 2006 and tended to be steady after 2008, this phenomenon might be related to farmland soil testing formula fertilization which began in Zhanjiang in 2006. The reason that the wastewater Nitrogen input increased rapidly after 2010 was the construction of industrial base of East Island in 2009. Total Nitrogen output increased by 16.35% during 2002-2006, and began to decrease and stabilize from 2007. Nitrogen load was relatively high and significantly correlated with the proportion of cultivated land area. The surplus of Nitrogen varied widely, which was 6 865.97 t in 2002 and down to 3 998.96 t in 2013, showing a reducing trend. Surplus of Nitrogen load decreased from 47.03 to 23.48 kg/hm2·per year. Our results show that the district is facing potential Nitrogen pollution caused by imbalance of Nitrogen budget.