洞庭湖立体养殖生态系统底泥总氮与总磷的时空变化及其与叶绿素a的关系

于2010—2011年夏、冬季对洞庭湖屈原管理区荞麦湖约500 hm2淡水珍珠养殖场底泥中总氮(TN)、总磷(TP)含量在时间、空间上的变化,与水体中叶绿素a 含量的关系及其在水稻修复下的含量变化进行了研究.结果表明:养殖场底泥中TN、TP的分布整体呈从南向北减少的趋势;随季节变化,底泥TN含量无明显变化,TP含量最高值出现在夏季,为1.64 mg/g,最低值出现在冬季,为0.26 mg/g;底泥TN、TP含量与叶绿素a含量呈正相关;养殖场内水稻作用下的底泥与养殖场中区底泥相比TN含量减少31.6%,TP含量减少45.1%,表明立体养殖生态系统和水稻种植对底泥的TN、TP有一定的修复效果

Spatiotemporal distribution of TN and TP in sediment of Three-dimensional ecosystem in Dongting lake and their relationships with chlorophyll-a

Spatiotemporal distribution of total nitrogen(TN),total phosphorus(TP) in sediment of Dongting lake where the 500 hm2 freshwater pearl culture system is located in Summer and Winter from 2010—2011 was observed.The relationship between these TN and TP with chlorophyll-a in the water and the content changes of TN and TP under rice ecosystem were investigated.The results showed that the contents of TN and TP in sediment decreased from the South to the North.There was no significant seasonal change in TN.The highest content of TP appeared in Summer,which was 1.64 mg/g,and the lowest TP content was in Winter,which was 0.26 mg/g.The contents of TN and TP in sediment were positively correlated to chlorophyll a content.TN and TP contents in the sediment where rice ecosystem is accessible reduced 31.6% and 45.1%,respectively,compared to those in the sediment located in the central of the culture system where rice ecosystem is inaccessible.These results suggest that three-dimensional culture and rice cultivation in the ecosystem could balance the contents of TN and TP in the sediment.