Knowledge is lacking on the factors controlling the structure and spatial distribution of earthworm communities within agroecosystems. We first hypothesized that forested riparian buffer strips (FRBS) within agricultural landscapes would be a refuge for earthworms, as we predicted higher soil moisture and organic matter inputs in FRBS than in adjacent agricultural fields (treatments = FRBS vs. Field). We further hypothesized that earthworms would be most abundant where the chemical quality of above- and belowground plant litter is high, or where soil disturbance is low. We conducted a field survey to quantify earthworm species abundances in FRBS and adjacent agricultural fields in two bioregions, namely Eastern Canada and Central Europe. At each of 77 sites, we collected and identified earthworms from three plots within FRBS and within adjacent agricultural fields. In each plot, we identified the tree species, understory vegetation, soil drainage class, agricultural crop as well as five soil physicochemical properties. In each bioregion and treatment, we found proportionately more endogeic than anecic or epigeic earthworm species. In Eastern Canada, there were proportionately fewer anecic and more epigeic individuals in FRBS than in fields; in Central Europe there were fewer endogeic and more anecic earthworms in FRBS than in fields. We found significant bioregion × treatment interactions on earthworm abundance and soil moisture. More specifically, in Eastern Canada we found higher earthworm abundance and soil moisture in FRBS, whereas in Central Europe we found higher earthworm abundance in fields and no treatment effect on soil moisture. In both bioregions, we found higher organic matter in FRBS than in fields. In Eastern Canada, earthworm abundance in deciduous and mixedwood stands were higher than in coniferous stands; in Central Europe, earthworm abundance was highest in deciduous stands only. Within FRBS in Eastern Canada, the abundance of the prominent endogeic species, Apporectodea rosea, was correlated with herbaceous plants, notably ferns and graminoids. Conditional regression tree analysis revealed positive relationships between earthworms and soil clay content, pH, moisture and organic matter. Our results suggest that local and landscape patterns in earthworm diversity can be predicted by soil and vegetation attributes, however the relative importance of these factors changes across continental scales due to differences in precipitation patterns and soil moisture availability. Comparing the distributions of earthworms across different scales provides insights into the potential of different species to spread into new habitats with climate change.

在控制农业生态系统中communities群落的结构和空间分布的因素方面缺乏知识。我们首先假设农业景观中的森林河岸缓冲带（FRBS）将是for的避难所，因为我们预测FRBS中的土壤水分和有机物输入要比邻近的农田高（处理= FRBS vs.田地）。我们进一步假设，在地上和地下植物凋落物的化学质量高或土壤干扰低的地方，earth将是最丰富的。我们进行了实地调查，以量化FRBS和两个生物区域（即加拿大东部和中欧）附近农业领域中earth的物种丰度。在77个站点中的每个站点，我们从FRBS内和相邻农业领域内的三个地块收集并鉴定了earth。在每个样地中，我们确定了树种，林下植被，土壤排水类别，农作物以及五种土壤理化特性。在每个生物区域和处理中，我们发现内生菌比例比食性或表皮earth物种更多。在加拿大东部，FRBS中的贫血个体和野性个体比田间成比例地减少。与中部地区相比，中欧的FRBS内生ge和无食an更少。我们发现significant对土壤丰度和土壤水分具有重要的生物区×处理相互作用。更具体地说，在加拿大东部，我们发现FRBS中的higher丰度和土壤湿度较高，而在中欧，我们发现田间的higher丰度更高，对土壤水分没有任何处理作用。在两个生物区域中，我们发现FRBS中的有机物含量高于田间。在加拿大东部，落叶林和混合林中的earth丰度高于针叶林。在中欧，仅在落叶林中in的丰度最高。在加拿大东部的FRBS中，丰富的内生物种丰富，迷迭香（Apporectodea rosea）与草本植物相关，尤其是蕨类和类动物。条件回归树分析表明worm与土壤粘土含量，pH，水分和有机质之间呈正相关。我们的研究结果表明，soil的多样性可以通过土壤和植被的属性来预测，但是由于降水模式和土壤水分有效性的差异，这些因素的相对重要性在整个大陆范围内都会发生变化。比较across在不同尺度上的分布，可以洞悉不同物种随着气候变化而传播到新的栖息地中的潜力。