Ladewig Samantha M, Coco Giovanni, Hope Julie A, Vieillard Amanda M, Thrush Simon F
Institute of Marine Science, University of Auckland, Private Bag 92019, Auckland, New Zealand.
School of Environment, University of Auckland, Private Bag 92019, Auckland, New Zealand.
Sci Total Environ. 2023 Feb 1;858(Pt 3):160114. doi: 10.1016/j.scitotenv.2022.160114. Epub 2022 Nov 9.
Emerging research shows that microplastic pollution could be impacting seafloor ecosystem function, but this has been primarily demonstrated without environmental and ecological context. This causes uncertainty in the real-world effects of microplastic pollution and leaves out essential information guiding policy and mitigation. In this study, we take a well-supported sampling design and statistical approach commonly employed in benthic ecology to evaluate real-world effects of microplastic pollution on coastal, benthic ecosystem function. We utilised environmental gradients in the Waitemata Harbour of Auckland, New Zealand to evaluate the importance of commonly assessed biological, chemical, and geological sediment variables and the characteristics of microplastic contaminants in driving essential ecosystem functions. Our results showed that models including microplastic terms were more accurate and explained more variability than those without microplastic terms, highlighting that microplastics impact real-world seafloor ecosystem function. Specifically, microplastic fibers significantly influenced oxygen flux (p < 0.03) and the diverse forms of microplastics (i.e., richness) significantly influenced ammonium flux (p < 0.02). Additionally, interactions between microplastic fiber concentrations and mollusc abundances significantly contributed to oxygen flux (p < 0.02). These results provide the first evaluation of in situ relationships between microplastics and ecosystem function. Even more importantly, this study suggests the value of environmental and ecological context for addressing microplastic impacts on benthic ecosystems and argues for further field examination.
新出现的研究表明，微塑料污染可能正在影响海底生态系统功能，但这主要是在缺乏环境和生态背景的情况下得到证明的。这导致了微塑料污染在现实世界中的影响存在不确定性，并遗漏了指导政策制定和缓解措施的重要信息。在本研究中，我们采用了底栖生态学中常用的一种得到充分支持的采样设计和统计方法，以评估微塑料污染对沿海底栖生态系统功能的现实世界影响。我们利用新西兰奥克兰怀特玛塔港的环境梯度，来评估通常评估的生物、化学和地质沉积物变量以及微塑料污染物特征在驱动基本生态系统功能方面的重要性。我们的结果表明，包含微塑料项的模型比不包含微塑料项的模型更准确，并且解释了更多的变异性，这突出表明微塑料会影响现实世界中的海底生态系统功能。具体而言，微塑料纤维显著影响氧气通量（p < 0.03），微塑料的多种形式（即丰富度）显著影响铵通量（p < 0.02）。此外，微塑料纤维浓度与软体动物丰度之间的相互作用对氧气通量有显著贡献（p < 0.02）。这些结果首次评估了微塑料与生态系统功能之间的原位关系。更重要的是，本研究表明了环境和生态背景对于解决微塑料对底栖生态系统影响的价值，并主张进行进一步的实地考察。
