Center of Applied Ecology and Sustainability (CAPES), Pontificia Universidad Católica de Chile, Santiago, Chile.
INRAE, Avignon Université, UMR EMMAH, Avignon, France.
Environ Sci Pollut Res Int. 2024 Feb;31(10):16076-16084. doi: 10.1007/s11356-024-32078-7. Epub 2024 Jan 19.
The widespread use of copper-based pesticides, while effective in controlling plant diseases, has been identified as a major source of copper contamination in soils. This raises concerns about potential adverse effects on earthworms, key players in soil health and ecosystem function. To inform sustainable pesticide practices, this study aimed to establish copper toxicity thresholds for earthworm avoidance in agricultural soils impacted by copper-based pesticides. We collected 40 topsoil samples (0-5 cm) from orchards and vineyards in the O'Higgins Region of central Chile, and 10 additional soils under native vegetation as background references. A standardized avoidance bioassay using Eisenia fetida assessed the impact of copper-based pesticides on the soils. Total copper concentrations ranged between 23 and 566 mg kg, with observed toxic effects on earthworms in certain soils. The effective concentration at 50% (EC) for total soil copper, determined by Eisenia fetida's avoidance response, was 240 mg kg, with a 95% confidence interval of 193-341 mg kg. We further compared our EC values with existing data from agricultural soils impacted by mining activities. Interestingly, the results revealed a remarkable similarity between the thresholds for earthworm avoidance, regardless of the source of copper contamination. This observation underscores the universality of copper toxicity in agricultural ecosystems and its potential impact on soil biota. This study provides novel insights into copper toxicity thresholds for earthworms in real-world, pesticide-contaminated soils.
铜基农药的广泛使用虽然在控制植物病害方面非常有效，但已被确定为土壤中铜污染的主要来源。这引起了人们对铜基农药污染土壤中蚯蚓潜在不良影响的关注，因为蚯蚓是土壤健康和生态系统功能的关键参与者。为了制定可持续的农药实践，本研究旨在确定受铜基农药影响的农业土壤中蚯蚓回避的铜毒性阈值。我们从智利中部奥希金斯地区的果园和葡萄园收集了 40 个表层土壤样本（0-5 厘米），并从当地植被下收集了另外 10 个土壤作为背景参考。使用赤子爱胜蚓（Eisenia fetida）进行了标准化回避生物测定，以评估铜基农药对土壤的影响。土壤中的总铜浓度范围在 23 至 566 毫克/千克之间，某些土壤中观察到了对蚯蚓的毒性影响。赤子爱胜蚓回避反应确定的总土壤铜的有效浓度（EC）为 240 毫克/千克，95%置信区间为 193-341 毫克/千克。我们还将我们的 EC 值与受采矿活动影响的农业土壤的现有数据进行了比较。有趣的是，结果表明，无论铜污染的来源如何，蚯蚓回避的阈值之间存在惊人的相似性。这一观察结果强调了铜毒性在农业生态系统中的普遍性及其对土壤生物群的潜在影响。本研究为受现实世界农药污染土壤中蚯蚓的铜毒性阈值提供了新的见解。
