MARE - Marine and Environmental Sciences Centre, ARNET - Aquatic Research Network, Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal.
Environ Pollut. 2024 Feb 1;342:123108. doi: 10.1016/j.envpol.2023.123108. Epub 2023 Dec 7.
Environmental pollution by anthropogenic litter is a global concern, but studies specifically addressing the interaction between macroplastics and macroinvertebrates in streams are scarce. However, several studies on plant litter decomposition in streams have also used plastic strips as a methodological approach to assess if macroinvertebrates colonize plant litter mostly as a substrate or a food resource. Looking at these studies from the plastic strips perspective may provide useful information on the interaction between macroplastics and macroinvertebrates in streams. I carried out a meta-analysis of 18 studies that have compared macroinvertebrate colonization of macroplastic litter and plant litter in streams to estimate the overall macroinvertebrate colonization of macroplastic litter relative to plant litter, and identify moderators of this difference. Macroinvertebrate colonization of macroplastic litter was overall lower (by ∼ 40%) compared with plant litter. However, differences in macroinvertebrate colonization between macroplastic litter and plant litter were observed when considering leaf litter but not wood litter, which may be a poorer substrate and food resource for macroinvertebrates. Also, differences in macroinvertebrate colonization between macroplastic litter and leaf litter were observed for shredders, collectors and predators, but not for grazers that may feed on the biofilm developed on macroplastics. Macroplastic litter supported lower macroinvertebrate density, biomass, abundance, and richness, but higher macroinvertebrate diversity than leaf litter. Higher macroinvertebrate diversity on macroplastic litter may have occurred when macroplastics represented more heterogeneous substrates (e.g., mixture of plastic types) than leaf litter (e.g., needles). Differences in macroinvertebrate abundance between macroplastic litter and leaf litter were not significantly affected by plastic type, mesh opening size, plant functional group or plant identity. By testing previously untested hypotheses, this meta-analysis guides future empirical studies. Future studies should also consider the geographical areas most affected by macroplastic pollution and the plastic types most often found in the streams.
人为垃圾造成的环境污染是一个全球性的问题，但专门研究宏观塑料与溪流中大型无脊椎动物相互作用的研究却很少。然而，一些关于溪流中植物凋落物分解的研究也使用塑料条作为一种方法学方法，以评估大型无脊椎动物是否主要将植物凋落物作为基质或食物资源进行定殖。从塑料条的角度来看这些研究，可以为溪流中大型塑料与大型无脊椎动物之间的相互作用提供有用的信息。我对 18 项比较溪流中大型塑料垃圾和植物凋落物上大型无脊椎动物定殖的研究进行了荟萃分析，以估计大型无脊椎动物对大型塑料垃圾的总体定殖率，并确定这种差异的调节因素。与植物凋落物相比，大型无脊椎动物对大型塑料垃圾的定殖总体上较低（约 40%）。然而，当考虑叶凋落物而不是木凋落物时，观察到大型无脊椎动物对大型塑料垃圾和植物凋落物的定殖存在差异，这可能是大型无脊椎动物较差的基质和食物资源。此外，在碎食者、收集者和捕食者中观察到大型无脊椎动物对大型塑料垃圾和叶凋落物的定殖存在差异，但在以可能以大型塑料上的生物膜为食的食草动物中则没有观察到这种差异。大型塑料垃圾支持较低的大型无脊椎动物密度、生物量、丰度和丰富度，但多样性较高。大型无脊椎动物在大型塑料垃圾上的多样性较高，可能是因为大型塑料比叶凋落物（如针叶）更具异质性（如多种塑料类型的混合物）。大型无脊椎动物在大型塑料垃圾和叶凋落物之间的丰度差异不受塑料类型、网眼大小、植物功能群或植物身份的显著影响。通过检验以前未经检验的假设，这项荟萃分析为未来的实证研究提供了指导。未来的研究还应考虑受大型塑料污染影响最大的地理区域和溪流中最常见的塑料类型。
