National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan.
Department of Evolutionary Studies of Biosystems, The Graduate University for Advanced Studies (Sokendai), Hayama, Kanagawa, Japan.
PLoS One. 2020 Jul 2;15(7):e0229052. doi: 10.1371/journal.pone.0229052. eCollection 2020.
Rice paddy irrigation ponds can sustain surprisingly high taxonomic richness and make significant contributions to regional biodiversity. We evaluated the impacts of pesticides and other environmental stressors (including eutrophication, decreased macrophyte coverage, physical habitat destruction, and invasive alien species) on the taxonomic richness of freshwater animals in 21 irrigation ponds in Japan. We sampled a wide range of freshwater animals (reptiles, amphibians, fishes, mollusks, crustaceans, insects, annelids, bryozoans, and sponges) and surveyed environmental variables related to pesticide contamination and other stressors listed above. Statistical analyses comprised contraction of highly correlated environmental variables, best-subset model selection, stepwise model selection, and permutation tests. Results showed that: (i) probenazole (fungicide) was a significant stressor on fish (i.e., contamination with this compound had a significantly negative correlation with fish taxonomic richness), (ii) the interaction of BPMC (insecticide; also known as fenobucarb) and bluegill (invasive alien fish) was a significant stressor on a "large insect" category (Coleoptera, Ephemeroptera, Hemiptera, Lepidoptera, Odonata, and Trichoptera), (iii) the interaction of BPMC and concrete bank protection was a significant stressor on an "invertebrate" category, (iv) the combined impacts of BPMC and the other stressors on the invertebrate and large insect categories resulted in an estimated mean loss of taxonomic richness by 15% and 77%, respectively, in comparison with a hypothetical pond with preferable conditions.
稻田灌溉池塘可以维持惊人的高分类丰富度，并对区域生物多样性做出重大贡献。我们评估了农药和其他环境胁迫因素（包括富营养化、大型植物覆盖率降低、物理生境破坏和入侵外来物种）对日本 21 个灌溉池塘中淡水动物分类丰富度的影响。我们采样了广泛的淡水动物（爬行动物、两栖动物、鱼类、软体动物、甲壳类动物、昆虫、环节动物、苔藓动物和海绵动物），并调查了与农药污染和上述其他胁迫因素相关的环境变量。统计分析包括高度相关的环境变量的收缩、最佳子集模型选择、逐步模型选择和置换检验。结果表明：（i）丙环唑（杀菌剂）是鱼类的一个重要胁迫因素（即这种化合物的污染与鱼类分类丰富度呈显著负相关），（ii）BPMC（杀虫剂；也称为fenobucarb）和蓝鳃太阳鱼（入侵外来鱼类）的相互作用是一个“大型昆虫”类别的重要胁迫因素（鞘翅目、蜉蝣目、半翅目、鳞翅目、蜻蜓目和毛翅目），（iii）BPMC 和混凝土护岸的相互作用是一个“无脊椎动物”类别的重要胁迫因素，（iv）BPMC 和其他胁迫因素对无脊椎动物和大型昆虫类别的综合影响导致与假设条件下具有较好条件的池塘相比，分类丰富度分别估计平均减少了 15%和 77%。
