鄱阳湖候鸟栖息地湖泊悬浮有机质的碳氮分布及来源分析--以大湖池和沙湖为例  

Source and distribution of carbon and nitrogen in the suspended organic matter in the migratory bird habitat of Poyang Lake: The case study of Lake Dahuchi and Lake Shahu

作　　者：梁越 肖化云 刘小真[2] 胡倩倩 丁新航 肖浩 杨慧慧 LIANG Yue;XIAO Huayun;LIU Xiaozhen;HU Qianqian;DING Xinhang;XIAO Hao;YANG Huihui(Jiangxi Province Key Laboratory of the Causes and Control of Atmospheric Pollution,State Key Laboratory Breeding Base of Nuclear Resources and Environment,School of Water Resources&Environmental Engineering,East China University of Technology,Nanchang 330013,P.R.China;Key Laboratory of Poyang Lake Environment and Resource Utilization,Ministry of Education,School of Resources Environmental&Chemical Engineering,Nanchang University,Nanchang 330047,P.R.China)

机构地区：[1]东华理工大学江西省大气污染成因与控制重点实验室,核资源与环境国家重点实验室培育基地,水资源与环境工程学院,南昌330013 [2]南昌大学环境与化工学院,鄱阳湖环境与资源利用教育部重点实验室,南昌330047

出　　处：《湖泊科学》2018年第6期1655-1663,共9页Journal of Lake Sciences

基　　金：国家自然科学基金项目(41563001);国家重大研究与开发项目(2016YTA0601000);东华理工大学核资源与环境国家重点实验室培育基地自主基金项目(Z1610);东华理工大学江西省大气污染成因与控制重点实验室开放基金项目(AE1602);东华理工大学博士科研启动金项目(DHBK2015326)联合资助.

摘　　要：以江西鄱阳湖国家级自然保护区的2个湖泊——大湖池和沙湖为研究对象,分析不同季节和水位悬浮有机质的碳氮稳定同位素(δ^(13)C和δ^(15)N)及碳氮比值(C/N)的变化特征,甄别悬浮有机质的来源.结果表明:在不同水位条件下,悬浮有机质的δ^(13)C和δ^(15)N均存在差异显著性.沙湖5月水位上涨时,悬浮有机质δ^(13)C最正,均值为-26.4‰±0.9‰,10月退水后,δ^(13)C最负,均值为-31.2‰±1.1‰.悬浮有机质δ^(15)N值在5月和8月较低(范围为3.5‰~5.5‰),10月也相对较低,均值为6.1‰±0.6‰,而12月相对较高(7.3‰~10.8‰).悬浮有机质C/N值在10月最低,均值为6.5±0.6,小于7,与其他各月的C/N有显著差异,而其他各月C/N在7.8~8.7之间,不存在显著差异.大湖池悬浮有机质δ^(13)C、δ^(15)N各月的变化趋势与沙湖类似,并且两个湖泊在相同月份的δ^(13)C、δ^(15)N或C/N均不存在显著差异,但大湖池的δ^(13)C和δ^(15)N比沙湖的δ^(13)C和δ^(15)N均值略偏正0.1‰~0.5‰,C/N比沙湖的C/N略偏低0~0.4.有机δ^(13)C、δ^(15)N结合C/N示踪表明,大湖池和沙湖的悬浮有机质在5月水位上涨和8月丰水期主要来源于河流运输的土壤有机质,表层沉积物对5月悬浮有机质也有一定贡献(16%),水生浮叶植物对8月悬浮有机质有一定贡献(25%); 10月秋季退水后悬浮有机质主要来源于藻类(77%),表层沉积物有一定贡献(23%); 12、3和4月冬、春季枯水期悬浮有机质主要来源于表层沉积物,候鸟粪便对12月悬浮有机质有较大贡献(40%),湿地植物碎屑对3和4月有较大贡献(47%和51%).We discriminated the origins of suspended organic matters in different seasons and water levels by carbon and nitrogen stable isotopes(δ13 C andδ15 N)and ratio(C/N)in Lake Dahuchi and Lake Shahu,national nature reserve of Poyang Lake in Jiangxi Province.The results showed thatδ13 C orδ15 N varied in different water levels.When water level rose in May,theδ13 C reached the highest value with average-26.4‰±0.9‰.In the dry season October,theδ13 C has the lowest value,average-31.2‰±1.1‰.Theδ15 N were of lower values in flooding seasons,however relativity high values in dry seasons.The C/N in October were lowest,average 6.5±0.6 and less than 7.In other months C/N were between 7.8 and 8.7.The variation ofδ13 C,δ15 N and C/N ratio in each month was similar between Lake Dahuchi and Lake Shahu,without significant difference.However,theδ13 C andδ15 N in Lake Dahuchi were more than 0.1‰-0.5‰and C/N were lower than 0-0.4 than those of Lake Shahu.At high water levels in May and August,the suspended organic matters were mainly from soil through rivers transportation,with 16%from surface sediment in May and 25%from aquatic floating-leaved plant in August.The suspended organic matters in October were mainly from algae(77%).At lower water levels of December,March and April,the suspended organic matters were mainly from surface sediments,and the excrement of migratory bird accounted for 40%in December.The phyto-detritus in wetland accounted for 47%and 51%in March and April,respectively.

关 键 词：鄱阳湖 悬浮有机质 同位素 来源 候鸟栖息地 大湖池 沙湖 

分 类 号：X524[环境科学与工程—环境工程]