太湖地区氮素湿沉降动态及生态学意义:以常熟生态站为例  

Dynamics and ecological significance of nitrogen wet-deposition in Taihu Lake region—Taking Changshu Agro-ecological Experiment Station as an example

作　　者：王小治[1,2] 朱建国[1] 高人[3] 宝川靖和 

机构地区：[1]中国科学院南京土壤研究所,土壤与农业可持续发展国家重点实验室 [2]扬州大学,扬州225009 [3]福建师范大学 [4]国际农林水产业研究中心

出　　处：《应用生态学报》2004年第9期1616-1620,共5页Chinese Journal of Applied Ecology

基　　金：国家重点基础研究发展规划资助项目 (G19990 1180 6)

摘　　要：在常熟生态站 2 0 0 1年 6月至 2 0 0 3年 5月连续两年定位收集湿沉降 ,对太湖地区氮素湿沉降动态进行研究 .结果表明 ,湿沉降氮输入量季节变化显著 ,夏、春季高 ,秋、冬季低 .在湿沉降输入氮中NH+ 4 N、NO-3 N和DON的比例分别为 4 7 6 %、35 1%和 17 4 % .湿沉降中NH+ 4 N主要来自当地农田的氨挥发 ,湿沉降NH+ 4 N月输入量随月降雨量增加而增加 (R2 =0 3178 ) .该地区空气中NO-3 N浓度相对比较稳定 ,湿沉降中NO-3 N浓度与降雨量呈负相关 (R2 =0 4 2 0 5 ) .湿沉降NO-3 N月输入量与月降雨次数呈直线正相关 (R2 =0 6 75 7 ) ,而与月降雨量相关性较差 (R2 =0 1985 ) .湿沉降TN年输入量为2 7 0kg·hm-2 ,并在所有降雨中 ,氮浓度均超过水体富营养化阈值 (0 2mg·L-1) .Nitrogen wet deposition was monitored for two years (2001.6～2003.5) at the Changshu Ecological Station in Taihu Lake region.The results showed that the amount of nitrogen wet deposition had a strong seasonal pattern,with higher levels in summer and spring,and low values in autumn and winter.The proportions of NH + 4-N,NO - 3-N and DON (dissolved organic nitrogen) to TN (total nitrogen) inputted by wet deposition were 47.6%,35.1% and 17.4%,respectively.Ammonia volatilization from farmland was the most important source of NH + 4-N in wet deposition.The monthly NH + 4-N input from wet deposition increased with monthly rainfall(R 2=0.3178 ** ),while the monthly NO - 3-N input from wet deposition had a lower correlation (R 2=0.1985 *) with monthly rainfall but positively related with the time of rainfall (R 2=0.6757 *** ).The NO - 3-N concentration in the air was relatively steady in a period of time.Its concentration in wet deposition had a negative correlation with rainfall (R 2=0.4205 *** ).The annual TN input from wet deposition was 27.0 kg·hm -2 ,but its concentration in each rainfall was higher than 0.2 mg·L -1 (the threshold N concentration for inland water eutrophication).The nitrogen inputted by wet deposition had an ecological significance on both nitrogen balance in agroecosystem and eutrophication.

关 键 词：太湖地区 氮素湿沉降 季节动态 生态学意义 

分 类 号：X52[环境科学与工程—环境工程]