太湖不同湖区无机氮转化潜力  

Comparative Study on Transformation Potential of Dissolved Inorganic Nitrogen in Different Parts of Lake Taihu.

作　　者：曾巾 杨柳燕[1] 肖琳[1] 杜宏伟[1] 

机构地区：[1]污染控制与资源化研究国家重点实验室/南京大学环境学院,江苏南京210093

出　　处：《生态与农村环境学报》2008年第1期63-67,共5页Journal of Ecology and Rural Environment

基　　金：国家高技术发展计划(2002AA60101);国家重点基础研究发展计划(2002CB412307)

摘　　要：采集太湖梅梁湾和东太湖的水样和沉积物，在实验室内模拟研究不同湖区水体中溶解性无机氮（DIN）短期内的转化潜力。研究结果表明，太湖藻型湖区（梅梁湾）和草型湖区（东太湖）水体中存在着强烈的硝化作用，NH4^＋-N和NO3^--N含量之间表现出显著的负相关关系（P〈0．05或P〈0．01），NH4^＋-N质量浓度下降速率为0．08—0．19mg·L^-1·d^-1。在同样的试验条件下，藻型湖区硝化速率高于草型湖区。NH4^＋-N初始浓度越高则硝化速率也越高，不添加外源氮时硝化速率随着时间的推移而逐渐降低。藻型湖区的反硝化作用强于草型湖区。室内模拟试验20d后，沉积物中TN含量平均下降了3．7％，东太湖水样中平均下降26．7％，梅梁湾平均下降42．2％。湖泊沉积物是进行反硝化作用的重要场所。短期内DIN的转化潜力反映了不同湖区氮素转化速率，也反映了不同生态类型水体对湖泊氮素转化的影响。Samples of waters and deposits were collected from algae-dominated Meiliang Bay and macrophyte-dominated East Lake Taihu for in-lab determination of DIN （ dissolved inorganic nitrogen） transformation potentials within 20 days. Results demonstrate that rapid nitrifications existed in the sediments and waters of the two lake zones, and there was remarkable negative correlation between NH4^＋ -N and NO3^- -N （ P 〈 0.05 or P 〈 0.01 ）. The nitrification rate in the algaedominated zone was a little higher than in the macrophyte-dominated zone in the microcosm under the same condition, and the higher the initial NH4^＋ -N concentration, the higher the nitrification rate. Nitrification rates decreased gradually with time when no extraneous nitrogen was added. Denitrification was also stronger in the Meiliang Bay than in the East Lake. After 20 clays in lab, TN declined by 3.7% （on average） in the sediments, by 26.7% in the water from the East Lake, and by 42.2% in the water from the Meiliang Bay, suggesting that sediment was the most important place for denitrification. Transformation potential of DIN within a short period of time reflects not only nitrogen transformation rate, but also effects of water bodies different in eco-type on cycling of nitrogen in the lake.

关 键 词：梅梁湾 东太湖 DIN 硝化作用 反硝化作用 

分 类 号：X142[环境科学与工程—环境科学] X172