Abstract：
Plastic pollution is a ubiquitous problem that poses a threat to society and the environment. The issue is especially pervasive in the aquatic environment, where large amounts of plastic debris accumulate from numerous anthropogenic pathways. Relatively little is known about the extent of macroplastics in African subtropical Austral rivers, where management strategies are lacking. This study quantifies and compares the variation in macroplastic abundances along the Mvudi River, South Africa, over four sites and four seasons. We observed a non-significant difference in macroplastic abundance and variation across sites and seasons, with pollution therefore widespread across these contexts. However, the diversity of plastic debris (i.e. γ-diversity value) decreased generally along sites, with most macroplastic items being collected during winter, and fewer macroplastic during autumn. We observed high abundances of macroplastic debris on the shoreline compared to the mainstream, with high proportional abundances of plastic bags and film (> 57.8%) macroplastic physical type across all sites and seasons. We also observed a high proportional abundance of the polymer polypropylene (> 25.3%) across seasons. The information derived from this study serves as the baseline for understanding seasonal variations in plastic debris and their driving factors on this and other subtropical Austral rivers.
摘要：
塑料污染是一个普遍存在的问题，对社会和环境构成威胁。这个问题在水生环境中尤其普遍，大量的塑料碎片从许多人为途径积累。对非洲亚热带南方河流中的大型塑料的程度知之甚少，缺乏管理策略的地方。这项研究量化和比较了姆武迪河沿岸大塑性丰度的变化，南非,四个地点和四个季节。我们观察到跨地点和季节的大塑丰度和变化的非显着差异，因此污染在这些环境中普遍存在。然而,塑料碎片的多样性(即γ-多样性值)总体上沿站点下降，大多数大型塑料物品都是在冬天收集的，秋季宏观塑料较少。与主流相比，我们观察到海岸线上大量的大型塑料碎片，在所有地点和季节中，具有高比例的塑料袋和薄膜（>57.8％）大塑性物理类型。我们还观察到跨季节的聚合物聚丙烯的高比例丰度(>25.3%)。从这项研究中获得的信息可作为了解塑料碎片的季节性变化及其在该和其他亚热带南方河流上的驱动因素的基线。
