Biology Department, Duke University, Durham, North Carolina 27708, United States.
Duke University Program in Ecology, Durham, North Carolina 27708, United States.
Environ Sci Technol. 2020 Jul 21;54(14):8878-8889. doi: 10.1021/acs.est.0c00510. Epub 2020 Jun 30.
The use of novel pesticides containing nanomaterials (nanopesticides) is growing and is considered a promising approach to reduce the impacts of agriculture on the environment and human health. However, the environmental effects of these novel agrochemicals are not fully characterized, and more research is needed to determine the benefits and risks they confer. Here, we assessed the impacts of repeated exposures to a Cu(OH) nanopesticide on the soil and sediment biodiversity of target (terrestrial) and nontarget (wetland) ecosystems by performing long-term outdoor mesocosm experiments. As pesticides are often used concomitantly with other agrochemicals, we also tested for interactive effects between nanopesticide exposure and fertilization treatments in both ecosystems. We used high-throughput sequencing on three marker genes to characterize effects on bacterial, fungal, and total eukaryotic community structure and diversity. Interestingly, we found limited effects of nanopesticide exposure on the terrestrial soil communities. Conversely, we found significant shifts in the sediment communities of the wetland mesocosms, especially for eukaryotes (protists, fungi, and algae). In the absence of fertilization, fungal and total eukaryotic community compositions exposed to nanopesticides for long periods of time were distinct from unexposed communities. We identified 60 taxa that were significantly affected by nanopesticide exposure, most of which were microeukaryotes affiliated to cercozoans, Gastrotricha, or unicellular algal taxa. Our study suggests that this nanopesticide has limited effects on the soil biodiversity of a target terrestrial agroecosystem, while nontarget aquatic communities are more sensitive, particularly among protists which are not targeted by this bactericide/fungicide.
新型含纳米材料的农药（纳米农药）的使用正在增加，被认为是减少农业对环境和人类健康影响的一种有前途的方法。然而，这些新型农用化学品的环境影响尚未完全确定，需要更多的研究来确定它们带来的益处和风险。在这里，我们通过进行长期的户外中观实验，评估了重复暴露于铜（OH）纳米农药对目标（陆地）和非目标（湿地）生态系统的土壤和沉积物生物多样性的影响。由于农药通常与其他农用化学品一起使用，我们还测试了纳米农药暴露和施肥处理在这两个生态系统中的相互作用。我们使用三个标记基因的高通量测序来描述对细菌、真菌和总真核生物群落结构和多样性的影响。有趣的是，我们发现纳米农药暴露对陆地土壤群落的影响有限。相反，我们发现湿地中观模型中的沉积物群落发生了显著变化，特别是对于真核生物（原生动物、真菌和藻类）。在没有施肥的情况下，暴露于纳米农药很长时间的真菌和总真核生物群落的组成与未暴露的群落明显不同。我们确定了 60 个受纳米农药暴露显著影响的分类群，其中大多数是与肉足虫、Gastrotricha 或单细胞藻类分类群有关的微真核生物。我们的研究表明，这种纳米农药对目标陆地农业生态系统的土壤生物多样性影响有限，而非目标水生群落则更为敏感，特别是对这种杀菌剂/杀真菌剂不针对的原生动物。
