春季太湖水域无机氮湿沉降来源初探  

Sources of Inorganic Nitrogen in Wet Deposition in Taihu Lake in Spring

作　　者：王雪梅[1] 杨龙元[2] 秦伯强[2] 纪玲玲[3] 金辉[1] 

机构地区：[1]中山大学环境科学与工程学院,广东广州510275 [2]中国科学院南京地理与湖泊研究所,江苏南京210008 [3]解放军理工大学气象学院一系,江苏南京211101

出　　处：《中山大学学报（自然科学版）》2006年第4期93-97,共5页Acta Scientiarum Naturalium Universitatis Sunyatseni

基　　金：国家自然科学基金委与香港资助局合作项目(N-HKUST612/01;40110734)

摘　　要：对2003年春季太湖站降雨资料进行分析,结果表明春季太湖水域NO3--N、NH4+-N的平均浓度分别为0.9和1.6mg/L。NO3--N与降雨量的相关系数是NH4+-N的两倍。利用气团后向轨迹分类法以及天气形势得到春季影响太湖流域的主要是海洋性降水,春季海洋性降水中NO3--N、NH4+-N沉降通量分别为1.01 kg/hm2、1.95kg/hm2,而大陆性降水中NO3--N、NH4+-N沉降通量分别为0.13和0.26 kg/hm2。同时利用气团后向轨迹,在海洋性过程中对云下气团进行分类,结论是北方气团对太湖水域氮的输送及沉降负荷最大,NO3--N、NH4+-N的沉降量分别占总沉降量的53.5%和57.9%,西南气团次之,NO3--N、NH4+-N的沉降量分别占总沉降量的34.6%、32.8%,局地气团最小,NO3--N和NH4+-N的沉降量分别只占总沉降量的11.9%、9.3%。Eutrophication in Taihu Lake region has become a serious problem as the economy developed rapidly in the Yangtze River Delta district. In addition to the materials from river point-sources and runoff area-sources, the nutritive elements input from the lake outskirt also increased step by step in recent years. The nutrition elements input from the ambient can influence the different ecosystems in the lake in different ways from what river pointsources and runoff area-sources do. In this paper, the precipitation data in spring of 2003 in Taihu Lake station and Tuoshan station were analyzed to study the inorganic nitrogen deposition flux and its origin. The averaged NO3^--N, NH4^＋-N concentration is 0.9 and 1.6 mg/L, respectively. The relative coefficient between NO3^--N and amount of rainfall is two times as NH4^＋-N. The oceanic precipitation is the dominate using Taihu Lake station data according to backward trajectory and synoptic pattern results. The deposition flux in the oceanic precipitation of NO3^--N, NH4^＋-N is 1.01, 1.95 kg/hm^2, respectively, whereas the deposition flux in the continental precipitation of NO3^-- N, NH4^＋-N is 0. 13, 0. 26 kg/hm^2, respectively. Under the oceanic precipitation, three air masses under cloud were identified according to backward trajectory results. Air mass came from NE has the highest contribution to total nitrogen deposition flux. The air mass came from SW is the second one. The local air mass has the lowest contribu- tion compared to others. The ratios of NE, SW, local air mass NO3^--N contribution to total nitrogen deposition flux are 53.5% , 34. 6% and 11.9% , respectively. For NH4^＋-N, the ratios are 57.9% , 32.8% , 9.3% , respectively. Although the local one weighed small, it impacted on the ecosystem mostly, demonstrated by the highest concentrations of NO3^--N and NH4^＋-N, followed by the NE air mass then SW ones.

关 键 词：太湖水域 无机氮来源 湿沉降通量 后向轨迹 

分 类 号：P421.615[天文地球—大气科学及气象学]