扎龙湿地丹顶鹤卵壳和羽毛DDTs残留量及其年际变化特征

Annual Change in Dichloro Diphenyl Trichloroethanes(DDTs)Residue in Eggshell and Feathers of Migratory Grus japonensis at Zhalong Wetland

为了探讨扎龙湿地环境中残留的有机氯农药DDTs对丹顶鹤(Grus japonensis)带来的潜在生态风险,使用单因素方差检验法(one-way ANVOA)分析了2004—2021年我国迁徙丹顶鹤种群的卵壳和羽毛残留的DDTs质量分数年际变化特征。结果表明:2020和2021年的卵壳中未检测到残留的DDTs,显著低于2004年、2009年以及2014年的DDTs残留量(F=10.13,P=0.005);2020年和2021年羽毛残留的DDTs质量分数显著低于2009年和2014年(F=18.13,P=0.001)。卵壳中DDTs最高残留量为2009年S5样点处采集的样本(35.6 ng/g),2020年以后卵壳中DDTs残留量低于检测限;2009年羽毛中残留量在1500 ng/g以上,2020年和2021年丹顶鹤羽毛残留量低于100 ng/g。当前丹顶鹤卵组织残留的DDTs水平(7.5 ng/g)低于影响大型飞禽物种繁殖率的风险阈值(3000 ng/g)。2021年丹顶鹤栖息地的底泥及典型食物[中国圆田螺(Cipangopaludina chinensis)、龙虱(Cybister japonicus)和体长小于15 cm的鲤(Cyprinus carpio)]残留的DDTs质量分数低于风险阈值。近年来扎龙湿地环境DDTs的残留水平对丹顶鹤的生态健康影响较低,不足以造成丹顶鹤种群规模的显著变化。

To investigate the potential ecological risk posed by organochlorine pesticide dichloro diphenyl trichloroethanes(DDTs)on the migratory red-crowned crane(Grus japonensis),annual change of DDTs residues in the eggshell and feathers of migratory red-crowned crane in China from 2004 to 2021 were examined by one-way ANVOA method in this study.Results show that DDTs residues in the eggshells of 2020 and 2021 decreased significantly compared to that in 2004,2009 and 2014(F=10.13,P=0.005);similarly,DDTs residues in the feathers of 2020 and 2021 were lower than that in 2009 and 2014(F=18.13,P=0.001).The maximal level of DDTs in the eggshell was found at sampling site S5 in 2009 with 35.6 ng/g,nevertheless,the levels in the eggshells after 2020 were below the detection level;similarly,the DDTs residue in the feathers in 2009 was above 1,500 ng/g,but declined to below 100 ng/g in 2020 and 2021.The residue in the tissues of egg left by the crane(7.5 ng/g)was far below the risk threshold level 3,000 ng/g to decrease breeding success rate.The DDTs residues in the sediment of the habitat of the red-crowned crane and its typical food(Cipangopaludina chinensis,Cybister japonicus,and Cyprinus carpio with body length less than 15 cm)were generally lower than the risk threshold level.The ecological risk on the red-crowned crane posed by DDTs residue from the environment of Zhalong wetland was relatively low in the present,and which could not lead to a significant change in their population size.