Abstract：
Microplastic mixtures are ubiquitously distributed in global ecosystems and include varying types. However, it remains unknown how microplastic diversity affects the biotic interactions of microbes. Here, we developed novel experiments of 600 microcosms with microplastic diversity ranging from 1 to 6 types and examined ecological networks for microbial communities in lake sediments after 2 months of incubation at 15 and 20 °C. We found that microplastic diversity generally enhanced the complexity of microbial networks at both temperatures, such as increasing network connectance and reducing average path length. This phenomenon was further confirmed by strengthened species interactions toward high microplastic diversity except for the negative interactions at 15 °C. Interestingly, increasing temperatures further exaggerated the effects of microplastic diversity on network structures, resulting in higher network connectivity and species interactions. Consistently, using species extinction simulations, we found that higher microplastic diversity and temperature led to more robust networks, and their effects were additionally and positively mediated by the presence of biodegradable microplastics. Our findings provide the first evidence that increasing microplastic diversity could unexpectedly promote the complexity and stability of microbial networks and that future warming could amplify this effect.
摘要：
微塑料混合物普遍分布在全球生态系统中，包括不同的类型。然而,目前尚不清楚微塑料多样性如何影响微生物的生物相互作用。这里,我们开发了600个微观世界的新实验，这些微观世界具有1至6种类型的微塑料多样性，并在15和20°C下孵育2个月后研究了湖泊沉积物中微生物群落的生态网络。我们发现，微塑料多样性通常会在两个温度下增强微生物网络的复杂性，例如增加网络连接和减少平均路径长度。除了15°C下的负相互作用外，这种现象还通过增强物种对高微塑料多样性的相互作用得到了进一步证实。有趣的是,温度升高进一步夸大了微塑料多样性对网络结构的影响，导致更高的网络连接性和物种相互作用。始终如一，使用物种灭绝模拟，我们发现，更高的微塑料多样性和温度导致更强大的网络，它们的作用是由可生物降解的微塑料的存在所介导的。我们的发现提供了第一个证据，即增加微塑料多样性可以意外地促进微生物网络的复杂性和稳定性，并且未来的变暖可能会放大这种影响。
