Ecotoxicological assessment of silicate rock fertilizers using soil invertebrates

Abstract: The objective of this work was to evaluate the possible adverse effects of rock dusts on the avoidance behavior of earthworms and collembolans, as well as on the survival and reproduction of enchytraeids, in ecotoxicological tests using artificial and natural soils. The tests were performed following international guidelines (ISO 17512-2/2011, ISO 11267/1999, and NBR ISO 16387/2012), with some adaptations, in order to evaluate the effect of dusts from two silicate rocks, biotite schist and phonolite, at the concentrations of 0, 0.1, 1.0, 10, and 100%, in artificial and natural (Arenosol and Ferralsol) soils. The avoidance behavior of the earthworm Eisenia andrei and the collembolan Folsomia candida was evaluated, as well as the survival and reproduction of the enchytraeid Enchytraeus sp. Biotite schist and phonolite affected negatively earthworms when applied to the soil at concentrations equal to or higher than 1.0%. The observed effect was associated to the greater presence of salts, especially in the phonolite, and to changes in soil texture when higher concentrations were used. Negative effects on collembolans and enchytraeids were verified at concentrations of 10% or using pure rock dusts. Agronomic rates smaller than 1.0% (approximately 20 Mg ha-1) rock dusts do not cause avoidance behavior or reduction in the survival and reproduction of invertebrates in the soil.

摘要：本研究旨在通过人工土壤与天然土壤开展生态毒理学试验，评估岩尘对蚯蚓、弹尾虫（collembolans）的回避行为，以及对线蚓（enchytraeids）存活与繁殖的潜在不良影响。本试验参照国际指南（ISO 17512-2/2011、ISO 11267/1999及NBR ISO 16387/2012）并做适当调整，在人工土壤以及砂质新成土（Arenosol）、铁铝土（Ferralsol）两种天然土壤中，设置0、0.1、1.0、10及100%的浓度梯度，评估两种硅酸盐岩——黑云母片岩（biotite schist）与响岩（phonolite）所产生岩尘的影响。本试验同时评估了安德爱胜蚓（Eisenia andrei）与等节跳虫（Folsomia candida）的回避行为，以及线蚓属未定种（Enchytraeus sp.）的存活与繁殖情况。当黑云母片岩与响岩在土壤中的施用量达到或超过1.0%时，会对蚯蚓产生负面作用；该负面效应与岩尘中较高的盐类含量（尤以响岩为甚）以及高浓度处理下土壤质地的改变相关。当岩尘浓度达到10%或使用纯岩尘时，会对弹尾虫与线蚓产生负面影响。当岩尘的农业施用量低于1.0%（约20 Mg·ha⁻¹）时，不会引发土壤无脊椎动物的回避行为，也不会降低其存活与繁殖能力。