白洋淀湿地酶活性空间变化规律研究

白洋淀作为我国富营养化湖泊湿地的典型代表，湿地中的生源要素迁移转化直接影响水质演变趋势，湿地系统中的酶在生源要素的循环过程中具有难以替代的作用，直接影响生源要素的迁移转化特性。于2007年3-11月在白洋淀设置固定监测点，研究土壤磷酸酶含量的时空分布规律及其与土壤营养元素间的相关关系。研究结果表明，在人为污染源等因素影响下，湿地中土壤酶表现出较明显的空间分异规律。垂直层面上，湿地土壤表层0-10cm是酶活性最高区域，同时表层土壤磷酸酶活性普遍大于中下层土壤。水平空间分布上，从府河河口区域至白洋淀中心区域磷酸酶活性基本呈现减小趋势。结果表明在污染较严重的河口区域，磷酸酶活性小于污染较轻区域，使得河口区域土壤中磷含量将进一步累积，有可能导致水体污染进一步加剧，需要采取相应的对策和保护措施。

Spatial distribution of soil enzyme activities in wetlands of Baiyangdian

The enzyme kinetics of land/water ecotones in a shallow eutrophic wetland in China, dominated by a reed （Phragmites australis） community, were studied. Enzymes respond rapidly and directly to changes in nutrient and substrate availability by manip- ulating enzyme kinetics to best capitalize on environmental conditions, and enzyme activities have the potential to reflect changes in nutrient cycling. From March 2007 to November 2007 eight sampling stations were selected and detected to study the relationship between enzyme activities with soil nutrient. The result showed that the obvious spatial differences of enzyme activities and nutrients were present in eutrophication wetlands. In soil profile the enzyme activities in surface layer were significantly higher than those in themiddle and bottom layer. From the fiver mouth of Fuhe fiver to the middle area the enzyme activities decreased, and the enzyme activities were higher than the middle area of Baiyangdian wetlands, that may aggravate the water body condition.