【摘要】 2007-2008年对千岛湖水体中5个采样点(S1,S3,S4,S8,S9)的总氮、总磷、三态氮、溶解性总磷和可溶性活性磷等进行了不同深度的逐月监测,以研究探讨千岛湖营养盐的时空分布格局.结果表明,两年间总磷、总氮和硝酸盐氮浓度都呈现从上游(S1)至下游(S9)逐渐下降的趋势;2007-2008年汛期(3-7月)位于千岛湖上游新安江干流段的样点S1各种营养盐均为全年最高.但是2007年与2008年营养盐时空分布差异显著.2008年汛期(3-7月),S1的总磷和总氮浓度分别极显著低于和高于2007年同期.相对于2007年,虽然2008年具有更高的温度,但没有增强水体热稳定性.2008年强对流天气一方面通过打破水体热分层和促进水体混合,另一方面通过雨水带来大量的地表营养盐来影响营养盐的分布.汛期高浓度的总磷在1-2个月内平均降低64.4%,最大降低88.6%,显示千岛湖生态系统具有较强的净化能力.分析结果显示千岛湖营养盐时空分布总体格局是由水文、生物以及人类活动等各种因素之间的相互作用所产生的综合效应而形成的,而极端天气能够改变这一格局.更多还原

【Abstract】 The temporal and spatial distribution patterns of nutrients (N and P) were investigated according to the monthly monitoring the total nitrogen (TN),nitrate nitrogen (NO3-N),nitrite nitrogen (NO2-N),ammonia nitrogen(NH4-N),total phosphorus (TP) and soluble reactive phosphorus (SRP) at five sampling sites(S1,S3,S4,S8,S9)in Lake Qiandao during 2007-2008.The results showed that the concentration of TP,TN and NO3-N decreased gradually from upstream to downstream (from S1 to S9) during the two years.The concentrations of various nutrients at the upstream sampling site S1 located in the mainstream of Xin’anjiang River peaked during the rainy season (March-July).But there was much difference between 2007 and 2008 in the temporal and spatial distribution of nutrients.The concentration of TP and TN at sampling site S1 during rainy season in 2008 was very significantly lower and higher than those in 2007 respectively.Contrasted with 2007,although the water temperature was higher in 2008,and it had not increased the stability of the water column.The severe convective weather in 2008,by disturbing water stratification and increasing water mixing and carrying much nutrient to the lake,affected the distribution patterns of nutrients.The high level of total phosphorus concentration during flood seasons was reduced by 64.4% averagely and 88.6% in maximum within 1-2 months,suggesting the strong self-purification capacity of Lake Qiandao ecosystem.Our results suggested that the comprehensive effects made by the interaction among hydrology,organism,and human production activities determine the general patterns of temporal and spatial distributions of nutrients of Lake Qiandao,but which could be changed on extreme whether.更多还原