百年来滇池沉积物中不同形态氮分布及埋藏特征  

Distribution and Burial Characteristics of Nitrogen Forms in Sediment of Dianchi Lake During Last Century

作　　者：吴亚林[1] 李帅东[1] 江俊武 沈胤胤 黄昌春[1,2,3] 黄涛[1] 杨浩[1] 余艳红[4] 罗玉[4] 

机构地区：[1]南京师范大学地理科学学院,南京210023 [2]江苏省地理信息资源开发与利用协同创新中心,南京210023 [3]江苏省物质循环与污染控制重点实验室,南京210023 [4]云南省环境科学研究院,中国昆明高原湖泊国际研究中心,昆明650000

出　　处：《环境科学》2017年第2期517-526,共10页Environmental Science

基　　金：国家自然科学基金项目(41571324);国家自然科学基金青年科学基金项目(41503075);中国博士后科学基金项目(2015M581826);云南省环境科学研究院(中国昆明高原湖泊国际研究中心)开放基金项目

摘　　要：为探讨百年来滇池沉积物氮的组成、分布以及埋藏特征,2014年7月在滇池采集6根沉积柱进行氮形态及年代测定.结果表明滇池沉积物总氮含量高,为1 263.68~7 155.17 mg·kg^(-1),硝氮及氨氮含量低,分别为10.00~144.00 mg·kg^(-1)和9.20~146.50 mg·kg^(-1).沉积物中有机氮为主要存在形态,含量为255.80~5 644.25 mg·kg^(-1),平均占总氮含量的91.26%;滇池沉积物总氮污染严重,于70年代开始形成且90年代后期加剧,并呈现滇池南部>北部>中部的分布特征;近100年来滇池沉积物平均沉积速率为0.092~0.187 g·(cm^2·a)^(-1),随时间先增加后降低再升高,空间上由北向南逐渐降低.沉积物中总氮埋藏速率则随时间逐渐增加,在1990年后几乎呈直线增长,且由南向北逐渐降低;据估算,1900~2014年滇池沉积物总氮埋藏量达92 139.15 t,其中有机氮埋藏量为86 745.62 t,硝氮埋藏量为2 464.16 t,氨氮埋藏量为2 929.37 t.In order to analyze the composition, distribution and burial characteristics of nitrogen in sediments of Dianchi Lake in the last hundred years, 6 sediment cores were sampled in July 2014 to determine the contents of different nitrogen species and sedimentary age sequence. The integrated results demonstrated a high content of total nitrogen in sediments ranging from 1 263. 68- 7 155. 17 mg·kg ^- 1 . The contents of nitrate nitrogen and ammonium nitrogen were low, which were 10. 00-144. 00 mg·kg ^- 1 and 9. 20-146. 50 mg·kg ^- 1 , respectively. Organic nitrogen was the main component in the sediments, ranging from 255. 80 to 5 644. 25 mg·kg ^- 1 , composing a large average percentage of 91. 26% . In addition, the nitrogen pollution of sediment in Dianchi Lake has reached a high level and is becoming serious since 1970s, which surged in the late 1990s. The spatial difference of total nitrogen was obvious, with comparably the most in the south, less in the north and least in the center. The average deposition rate was changing from 0. 092 g·（cm^2·a）^ - 1 to 0. 187 g·（cm^2·a）^ - 1 in the last 100 years and increased first, then declined, finally showed a slight upward trend over time. The burial rate of total nitrogen in sediment increased over time and almost grew up straightly after 1990,which decreased from the south to the north of Dianchi Lake in space. It was estimated that the reserves of total nitrogen, organic nitrogen, nitrate nitrogen, ammonium nitrogen in the sediment were 92 139. 15 t, 86 745. 62 t, 2 464. 16 t, 2 929. 37 t, respectively, from 1900 to 2014.

关 键 词：滇池 沉积物 沉积速率 氮污染 氮埋藏 

分 类 号：X524[环境科学与工程—环境工程]