连云港海州湾海域表层水体和沉积物中微塑料的分布特征

近年来,微塑料成为国内外广泛关注的新型海洋污染物,海湾作为人类在海岸环境中的主要活动地区,一直是海洋污染物聚集地,但我国对近岸大部分中小型海湾环境中微塑料的分布状况仍鲜见报道.为了解我国近岸中小型海湾的微塑料污染特征,本研究以江苏省海州湾海域表层海水和沉积物中采集的微塑料为样本,通过定性和定量方法研究了表层水和沉积物中微塑料主要类型和丰度及空间分布特征.结果表明,海州湾表层水体和沉积物中的微塑料丰度分别为(2.60±1.40)个·m~(-3)和(0.33±0.26)个·g~(-1),在国内近岸环境(表层水0.33～545.00个·m~(-3),沉积物0.07～2.58个·g~(-1))中,海州湾表层水中的微塑料丰度处于较低水平,但沉积物中的微塑料处于较高水平.塑料污染物的粒径大小在水体中分布范围为0.08～13.48 mm,其中,微塑料(粒径5 mm)占91.8%,塑料污染物在沉积物中粒径的分布范围为0.04～14.74 mm,微塑料占91.4%,水体和沉积物中60%以上的微塑料粒径小于2.00 mm.海州湾海域微塑料的形态以纤维状为主,占92%;颜色以蓝色和黑色为主,占70%;材质以人造纤维和PET为主,占79.4%.表层水中微塑料的分布与悬浮物浓度分布具有显著的相关性(P0.05),沉积物中微塑料的分布受多方面因素影响,其分布规律与表层水中微塑料的分布以及沉积物中粒径的分布都具有较大差异性.通过对微塑料的形态特征以及成分组成的分析表明,海州湾的微塑料主要来源于海水养殖和沿岸陆源输入.

Distribution Characteristics of Microplastics in Surface Water and Sediments of Haizhou Bay, Lianyungang

In recent years, microplastics have emerged as a new marine pollutant and have attracted wide research attention. As the main activity areas of human beings in the coastal environment, gulfs have always been the hotspots of marine pollution. However, the distribution of microplastics in most small and medium-sized coastal environments has been rarely reported in China. To understand the characteristics of microplastic pollution in small and medium-sized inshore bays in China, the main types, abundance, and spatial distribution characteristics of microplastics in the surface water and sediments in Haizhou Bay of Jiangsu province were studied by qualitative and quantitative methods. The results showed that the abundances of microplastics in the surface water and sediments of Haizhou Bay were (2.60±1.40) n·m^-3 and (0.33±0.26) n·g^-1, respectively. In the domestic offshore environment, the abundance of microplastics was at a low level in the surface water, but at a high level in the sediments in Haizhou Bay (0.33-545.00 n·m^-3 and 0.07-2.58 n·g^-1, respectively). The range of size distribution of microplastics in water and sediments was 0.08-13.48 mm and 0.04-14.74 mm, respectively. More than 60% of the microplastics in water and sediments were small particles of sizes less than 2.00 mm. The shape of microplastics in Haizhou Bay was mainly fibrous, accounting for 92%. The main colors were blue and black, accounting for 70%. The materials were mainly man-made fibers and PET, accounting for 79.4%. There was a significant correlation between the distribution of microplastics in surface water and suspended matter concentration (P<0.05). The distribution of microplastics in sediments was affected by many factors, and its distribution pattern between the distribution of microplastics in surface water and the distribution of particle size in sediments was quite different. Through analysis of the morphological characteristics and composition of microplastics, the results showed that the microplastics in Haizhou Bay mainly come from mariculture and coastal land sources.