摘要
以^(210)Pb对广东新丰江水库XFJ-1孔进行了定年,以GC-ECD测定新丰江水库沉积钻孔中DDTs和HCHs的含量,通过对比其剖面变化特征与该类农药在我国的生产、使用历史,探讨了水库中DDT、HCH的历史输入途径.过去30年来,XFJ-1孔平均沉积速率为1.42cm/a,沉积物中HCHs和DDTs的含量分别为1.26-3.90ng/g和1.00-3.96ng/g.DDTs、HCHs含量从20世纪80年代初逐渐下降,总体上与我国1983年开始禁止DDT、HCH的大规模生产和使用这一历史事件相符.DDTs、HCHs及其化合物比值的剖面变化特征均表明:流域内后期土壤侵蚀、搬运的再循环污染物质(即二次污染源)对水库DDT和HCH的贡献不明显;相反,农药历史使用(即一次污染源)是其主要来源,大气沉降是其主要输入途径.此外,γ-HCH、o,p′-DDT和p,p′-DDT含量的垂直变化表明,大规模禁用以后这些化合物仍有少量新的输入,需引起重视.
Sediment Core XFJ-1 was collected from the Xinfengjiang Reservoir in Guangdong Province, and the samples after coreslicing were dated by the excess ^210pb. Each sediment layer was analyzed for HCH and DDT by equipment of the GC-ECD. The results show a time trend of HCH and DDT in the sediment core so that relationship between the source and transport pathway of these compounds can be discussed. Concentration of HCHs and DDTs in Core XFJ-1 ranges from 1.26 to 3.90ng/g and from 1.00 to 3.96ng/g, respectively. The concentration of HCHs and DDTs declined since the early 1980＇s, indicating that measures of HCH- and DDT-ban have been effective. Vertical distribution characteristics of HCHs and DDTs show these compounds were not come from the secondary source that was transported by runoff from the basin. The primary source was confirmed as the major source in sediment core, and was input by air dust deposition. Vertical profile of T-HCH, o,p′-DDT and p,p′-DDT indicate that the compounds still have new input after the ban.
出处
《湖泊科学》
EI
CAS
CSCD
北大核心
2010年第2期215-220,共6页
Journal of Lake Sciences
基金
中国科学院创新基地重要方向性项目(KZCX2-YW-Q02-01)
国家自然科学基金创新群体科学基金项目(40821003)联合资助
