降雨前后库滨带表层土壤养分研究

在官厅水库库滨地区对降雨前后库滨带表层土壤养分进行试验研究。结果表明,降雨前农田土壤总磷的含量最高,其次为湿生草本带,乔灌草带和挺水植物带则相对较低;土壤表层总氮的含量乔灌草带最高。降雨前后库滨带各区土壤表层的氮和磷大部分以颗粒态存在,库滨带各区表层颗粒直径<0.002 mm的土壤颗粒是颗粒态磷的主要载体,直径为0.02￣0.05 mm的土壤颗粒是颗粒态氮的主要载体。农田和乔灌草带表层土体截流了来水中的总磷,而挺水植物带则表现为总磷的释放,农田、乔灌草带和湿生草本带对总氮有去除作用,而以乔灌草带的去除效果最明显。

Alteration of Nutrition in Surface Soil at Buffer Zone of A Reservoir Before and After Rainfall

In order to study alteration of nutrition in the surface soil at buffer zone before and after rain,field tests have been done at the buffer zone of Guanting reservoir.The result showed that the amount of total phosphorus in the soil of farmland is the highest,while the wet grassland field with arbor shrub and grassland field and bulrush field is lower than that in farmland before rain.The total nitrogen in the soil of arbor shrub and grassland field is the highest.Both total nitrogen and total phosphorus exist as particulate state.Most of the particulate phosphorus exists in the soil grain with diameter of less than 0.002 mm.Most of the particulate nitrogen exists in the soil grain with diameter of a range between 0.02 and 0.05 mm.We also found that a part of total phosphorus was removed from runoff in arbor shrub and grassland field.On the other hand,the surface soil in bulrush field exported total phosphorus after rain.The farmland with arbor shrub and grassland and wet grassland are capable of removing total nitrogen,this situation is obviously in the arbor shrub and grassland field at buffer zone.