摘要
2005年8月在海南洋浦湾内湾取得1根柱状样,在铅-210定年的基础上分析沉积物粒度、总有机碳含量及其同位素值(δ13C)、总氮含量及其同位素值(δ15N)、生物硅含量、重金属(镍、镉、铬、铜、锌、铅)含量及有机氯农药(六六六、滴滴涕)含量等参数发现,111cm至表层,沉积物中有机碳、总氮、生物硅含量升高,特别是从45cm至表层,它们的含量明显增加,说明该湾内有富营养化趋势。由有机碳与总氮的原子比和有机碳同位素指示的物源信息可知,该湾内有机质来源为藻类和陆源脉管植物的混合,且以陆源输入为主。陆源有机碳含量与总有机碳含量的相关系数为0.917。自23cm至表层有机碳同位素明显偏轻,氮同位素偏重。从111cm至表层,重金属和有机氯农药含量升高。综合分析各环境指标可知,洋浦湾近百年来环境演变可分为三个时期,即20世纪70年代以前、70年代至90年代、90年代至21世纪初,洋浦湾经历了未污染期、轻度污染期、显著污染期。
In the summer of 2005, the Second Institute of Oceanography ,State Oceanic Administration has investigated adjacent sea of Hainan Island for sediment and environment studies,and collected a sediment core in the Yangpu Bay. On the basis of the dated sediment core, the grain size, total organic carbon and stable organic carbon isotope （δ^13 C）, total nitrogen and stable nitrogen isotope （δ^15 N）, biogenic silica, heavy metals（nickel, cadmium, chromium, copper, zinc, lead）, organochlorine pesticides （HCHs, DDTs） were analyzed. From 111 cm to surface, the concentrations of total organic carbon, total nitrogen and biogenic silica show increasing trends. Especially from 45 cm to surface, the trends are significant. So the conclusion can be obtained that accelerated entrophication occurred in the Yangpu Bay. The data of δ^13C and the atomic ratio of total organic carbon and total nitrogen reveal the mixing inputs of terrigenous and marine organic matter in the Yangpu Bay . And sediment organic carbon is dominated by terrigenous organic carbon. The corresponding relationship between terrigenous organic carbon and total organic carbon is good, and the value of the relationship coefficient is 0. 917. From 23 cm to surface, δ^13C was decreasing. From bottom to surface, δ^15N was increasing. From 111 cm to surface, the concentrations of heavy metal and organochlorine pesticides show increasing trends. Analyzing all indicators of environmental evolution, the results showed that the development of Yangpu Bay environment during last hundred years can be divided into three stages： before the 1970s characterized by good biogenic environment; from the 1970s to the 1990s, the concentrations of heavy metals, organochlorine pesticides and biogenic elements are increasing; and from the 1990s to the beginning of the 21 century, the environment was polluted by all elements mentioned, and resulted in eutrophication.
出处
《海洋学报》
CAS
CSCD
北大核心
2008年第4期95-103,共9页
基金
我国近海海洋综合调查与评价专项资助项目(908-01-CJ19)
国家海洋局第二海洋研究所基本科研业务费专项资助项目
关键词
洋浦湾
生源物质
碳
氮稳定同位素
富营养化
重金属
有机氯农药
Yangpu Bay of Hainan, China
organic carbon/nitrogen stable isotope
eutrophication
heavy metal, organochlorine pesticides
