学术论文

      三峡库区紫色土坡耕地小流域氮收支估算及污染潜势

      Input-output budgets for nitrogen in a typical purple soil sloping ploughland in Three Gorges areas

      摘要:
      为了解三峡库区氮素收支情况,进行污染潜势评价,对三峡库区典型紫色土坡耕地(新政小流域)进行了调查分析,结果表明,小流域氮输入量为918.26kg/(hm2.a),输出量为569.46kg/(hm2.a)。化肥氮是小流域氮输入的主要来源,占氮输入总量的57.63%;作物收获是小流域氮的主要输出方式,占氮输出总量的36.22%;小流域氮损失负荷为258.77kg/(hm2.a),气态氮损失是流域氮损失的主要形式,占流域损失氮总量的65.11%;流域氮养分平衡指数为3.4,氮素盈余负荷为348.80kg/(hm2.a),是流失风险值180kg/(hm2.a)的1.94倍,坡耕地氮污染潜势呈现。
      Abstract:
      The Xinzheng watershed in Zhongxian county,Chongqing,is a typical purple soil sloping ploughland in the Three Gorges areas.In 2009,the input-output budgets in this watershed is investigated and the results indicate that the nitrogen input is 918.26 kg/(hm2·a) and the output are 569.46 kg/(hm2·a).Furthermore,chemical fertilizer nitrogen is the main input source,accounting for 57.63%,and the main output track is nitrogen in crops,accounting for 36.22%.In this small watershed,the nitrogen loss load is 258.77 kg/(hm2·a).And the primary lost nitrogen is gaseous species,which is approximately 65.11% of the total lost nitrogen.In addition,nutrient nitrogen balance index is 3.4 in this watershed and the nitrogen surplus load is 348.80 kg/(hm2·a),much higher than the risk value,indicating potential occurrence pollution in ploughland.
      作者单位: 重庆大学三峡库区生态环境教育部重点实验室,重庆,400045
      刊 名: 重庆大学学报:自然科学版 ISTICEIPKU
      年,卷(期): 2011, 34(11)
      分类号: X131.2
      机标分类号: S15 S96
      在线出版日期: 2012年4月21日
      基金项目: 国家重大水专项资助项目,重庆市重点科技攻关项目