论文部分内容阅读
选择二百方子洪泛区湿地作为典型研究区,以NH4Cl为示踪剂,模拟研究了铵态氮在洪泛区湿地不同土层中的水平运移过程。结果表明,沼泽湿地土壤中铵态氮的运移通量随运移距离的增加呈一阶衰减指数变化;0~10cm土层中铵态氮的运移通量最小,20~60cm土层次之,10~20cm土层具有最高的铵态氮通量。各层土壤运移通量在0~6cm内最大,而后迅速下降,到18cm时3层土壤中铵态氮的运移通量相近并趋近于零。各层土壤中铵态氮的运移通量与土壤水扩散率及土壤含水量都呈一阶指数增长变化;在土壤水扩散率或土壤含水量达到一定数值前,铵态氮运移通量增长缓慢,之后则开始骤然增加。
Taking Erfangzi Floodplain as a typical study area, NH4Cl was used as a tracer to simulate the horizontal transport of ammonium nitrogen in different soil layers in floodplain wetlands. The results showed that the flux of ammonium nitrogen in marsh wetland changed first order with the increase of migration distance. The flux of ammonium nitrogen in 0-10 cm soil layer was the lowest. , 10 ~ 20cm soil layer has the highest ammonium nitrogen flux. The flux of soil transport in each layer was the largest in 0 ~ 6 cm, then decreased rapidly. The transport flux of ammonium nitrogen in three layers of soil reached similar to zero at 18 cm. The fluxes of NH 4 + -N in all soil layers showed a first-order exponential increase with soil water diffusivity and soil water content. Before the soil water diffusivity or soil water content reached a certain value, the NH 4 -N flux Slow growth, then began to increase suddenly.