Université de Toulouse, INP-ENSAT, Av. Agrobiopôle, 31326 Castanet-Tolosan, France; UMR 5245 CNRS-INP-UPS, EcoLab (Laboratoire d'écologie fonctionnelle), Avenue de l'Agrobiopôle, BP 32607, 31326 Castanet-Tolosan, France; ADEME (French Agency for Environment and Energy Management), 20 avenue du Grésillé, BP 90406, 49004 Angers Cedex 01, France.
INRA, UR 1115, Plantes et Systèmes Horticoles, Site Agroparc, 84914 Avignon cedex 09, France.
Sci Total Environ. 2015 Apr 1;511:738-46. doi: 10.1016/j.scitotenv.2014.11.101. Epub 2015 Jan 21.
The effects of metal(loid)s (Pb, Cd, Cu, Zn, As and Sb) from atmospheric fallout on earthworm communities were investigated in a fallow meadow located close to a 60-year-old lead recycling factory. We examined abundance and species diversity as well as the ratio of adult-to-juvenile earthworms, along five 140 m parallel transects. The influence of soil pollution on the earthworm community at the plot scale was put in context by measuring some physico-chemical soil characteristics (OM content, N content, pH), as well as total and bioavailable metal(loid) concentrations. Earthworms were absent in the highly polluted area (concentration from 30,000 to 5000 mg Pb·kg(-1) of dried soil), just near the factory (0-30 m area). A clear and almost linear relationship was observed between the proportion of juvenile versus mature earthworms and the pollution gradient, with a greater proportion of adults in the most polluted zones (only adult earthworms were observed from 30 to 50 m). Apporectodea longa was the main species present just near the smelter (80% of the earthworms were A. longa from 30 to 50 m). The earthworm density was found to increase progressively from five individuals·m(-2) at 30 m to 135 individuals·m(-2) at 140 m from the factory. On average, metal(loid) accumulation in earthworm tissues decreased linearly with distance from the factory. The concentration of exchangeable metal(loid)s in earthworm surface casts was higher than that of the overall soil. Finally, our field study clearly demonstrated that metal(loid) pollution has a direct impact on earthworm communities (abundance, diversity and proportion of juveniles) especially when Pb concentrations in soil were higher than 2050 mg·kg(-1).
研究了位于一个 60 年历史的铅回收厂附近休耕地中，大气沉降金属（loid）（Pb、Cd、Cu、Zn、As 和 Sb）对蚯蚓群落的影响。我们沿着 5 条 140 米长的平行样带检查了丰度和物种多样性以及成年和幼蚓的比例。通过测量一些理化土壤特性（OM 含量、N 含量、pH 值）以及总金属（loid）和生物可利用金属（loid）浓度，将土壤污染对斑块尺度蚯蚓群落的影响置于背景中。在高度污染区域（土壤干燥质量中 Pb 浓度为 30000-5000 mg/kg）和工厂附近（0-30 m 区域）没有发现蚯蚓。在污染梯度方面，幼蚓与成熟蚓的比例存在明显的几乎线性关系，在污染最严重的区域（仅在 30-50 m 处观察到成年蚯蚓）比例更大。在冶炼厂附近，主要物种是 Aporectodea longa（30-50 m 处 80%的蚯蚓是 A. longa）。从距离工厂 30 m 处的 5 条·m(-2)蚯蚓密度逐渐增加到 140 m 处的 135 条·m(-2)。平均而言，蚯蚓组织中金属（loid）的积累随距离工厂的增加而线性减少。蚯蚓表面粪便中的可交换金属（loid）浓度高于土壤中的整体浓度。最后，我们的实地研究清楚地表明，金属（loid）污染对蚯蚓群落（丰度、多样性和幼蚓比例）有直接影响，特别是当土壤中 Pb 浓度高于 2050 mg·kg(-1)时。
