【作者】 袁自瑛； 张展羽；

【Author】 Yuan Ziying,Zhang Zhanyu

【机构】 河海大学水利水电学院；

【摘要】 本文以次降雨条件下南方典型农田为研究对象,观测了降雨前后稻田和旱地地下水埋深、地下水氮素含量、土壤氮素含量。实验结果表明:对于地下水位,旱地中离农沟距离愈远,其埋深愈深,水稻田则相反,农沟起着补充旱地地下水和收集水稻田地下排水的作用。在旱地和稻田地下水中氮素含量均表现为:地下水越深的地方,各形态氮素含量越高,硝氮的含量明显高于氨氮。土壤氮素含量垂向分布规律均为:自上而下,氮素的含量逐渐减小,其水平方向的分布规律为:旱地表层(0～30cm)土壤氮素含量随离农沟距离的增加而增加,稻田则相反;深层(30～60cm)含量变化不大。水稻田和旱地土壤中氮素的含量在雨后均有所减低,且随着地下水埋深的增加,氮素在土壤和地下水中含量依次增加,说明地下水的水平移动不仅造成沿程土壤中氮素富集,还会使地下水中氮素浓度升高。更多还原

【Abstract】 Taking the typical farmlands in South China of dividual rain as the research objects,we have observed the groundwater table,groundwater nitrogen content,soil nitrogen content before and after rain in the paddy and dry-land.The results show that:in the dry-land, the greater of the distance from the farmland ditch,the deeper of the ground water level,while that is opposite in the paddy.The farmland ditch plays the roles of supplying the groundwater of the dryland and collecting the drainage of the paddy.Both the paddy and dry-land,the distribution law of the groundwater nitrogen concentration as follows:the deeper of the groundwater level,the higher of the various forms nitrogen content,and the content of nitrate nitrogen is significantly higher than that of the ammonia.The soil nitrogen content’s vertical distribution law is:from up to down,the nitrogen content decreases gradually;its horizontal distribution laws as:in the dryland,the surface(0～30cm) soil of nitrogen content increased with the distance from the farmland ditch increasing,that’s on the contrary in the paddy;while the soil nitrogen content in deep layer(30～60cm) changed a little.The soil nitrogen content reduced after storm both in the paddy and dryland,and with the deepening of groundwater level,the nitrogen content in soil and groundwater increase,that indicated:the horizontal movement of groundwater didn’t only cause the soil nitrogen enrichment,but also made the nitrogen concentration in groundwater increasing.更多还原