鄱阳湖水体悬浮有机质碳氮同位素分布特征及来源探讨  

Distribution and sources of stable organic carbon and nitrogen isotopes in suspended particulate organic matter of Poyang Lake

作　　者：王毛兰[1,2] 张丁苓 赖建平[1,2] 胡珂图 赖劲虎[1,2] 

机构地区：[1]南昌大学鄱阳湖环境与资源利用教育部重点实验室,江西南昌330047 [2]南昌大学环境与化学工程学院,江西南昌330031

出　　处：《中国环境科学》2014年第9期2342-2350,共9页China Environmental Science

基　　金：江西省自然科学基金(20114BAB213023);江西省教育厅科学技术研究项目(赣教技字[GJJ11283]号);南昌大学鄱阳湖环境与资源利用教育部重点实验室开放基金

摘　　要：通过对鄱阳湖及其入湖河流(赣江、抚河、信江、修水及饶河)水体悬浮有机质碳、氮同位素含量的测定,分析了鄱阳湖及其入湖河流水体悬浮有机质碳同位素(δ13CPOM)和氮同位素(δ15NPOM)时空分布特征,探讨了其水体悬浮有机质和氮素来源.结果表明,鄱阳湖区枯水期δ13CPOM、δ15NPOM值分布范围分别为-26.59‰^-24.91‰(n=9)和5.88‰~17.49‰(n=9),丰水期分别为-27.10‰^-25.88‰(n=9)和2.99‰~19.69‰(n=9);入湖河流水体枯水期δ13CPOM、δ15NPOM值变化范围分别为-27.79‰^-25.22‰(n=6)和2.87‰~9.26‰(n=6),丰水期分别为-28.07‰^-26.02‰(n=6)和2.12‰~8.75‰(n=6).有机质来源分析表明:C3植物是鄱阳湖区及其入湖河流水体悬浮有机质的主要来源;而氮素来源比较复杂,在不同季节和不同的地点也不尽相同,生活污水、化肥及其土壤流失氮是鄱阳湖区水体悬浮颗粒物氮素的3种主要来源;化肥、陆源有机质及其土壤流失氮是其入湖河流水体悬浮颗粒物氮素的3种主要来源.Fifteen samples from the Poyang Lake and its main tributaries （Ganjiang River, Fuhe River, Xinjiang River, Xiushui River and Raohe River） were collected to analyze organic carbon and nitrogen isotopes in suspended particles. In addition, the sources of organic matter and nitrogen in the suspended particulate organic matter were analyzed. The results showed that the organic carbon isotope composition （δ^13CPOM） ranged from-26.59‰to-24.91‰（n=9） and-27.10‰to-25.88‰（n=9） whereas the nitrogen isotope composition （δ^15NPOM） was from 5.88‰to 17.49‰and 2.99‰to 19.69‰in low water period and high water period, respectively in Poyang Lake area. In the suspended particulate organic matter of the main tributaries, theδ^13CPOM values ranged from-27.79‰to-25.22‰（n=6） and-28.07‰to-26.02‰（n=6）whereas theδ^15NPOM was from 2.87‰to 9.26‰and 2.12‰～8.75‰in low water period and high water period, respectively. The C3 plants were the main sources of the suspended particulate organic matter in Poyang Lake and its main tributaries. The sources of nitrogen in the suspended particulate organic matter were complex. Domestic sewage, chemical fertilizer and soil erosion were the main sources of nitrogen in the suspended particulate organic matter in the Poyang Lake. Whereas the chemical fertilizer, terrestrial organic matter and soil erosion were the main sources of nitrogen in the suspended particulate organic matter in its main tributaries.

关 键 词：鄱阳湖 悬浮有机质 碳同位素 氮同位素 物质来源 

分 类 号：X524[环境科学与工程—环境工程]