The excessive application of chemical fertilizers in intensively managed agricultural fields worldwide has resulted in soil degradation and biodiversity loss. This has contributed to a growing interest in sustainable management, such as organic farming. Until now, studies addressing the impact of conventional and organic management on soil biodiversity and functioning have mainly focused on arable farming and only a few reports are available on vegetable production. Vegetable farming is of particular interest, since management intensity is usually very high and there is an increasing demand for vegetable products. Soil nematodes are useful indicators of management intensity on soil ecosystem functioning because they occupy several trophic levels in soil micro-food webs and play a crucial role in nutrient cycling, pest suppression, and the regulation of microbial communities. In this study, we assessed the impact of management intensity and farming system on the community structure and functional guilds of soil nematodes, comparing 20 conventional vegetable fields, 20 organic vegetable fields, and 20 extensive grasslands in Switzerland, analyzing over 30’000 nematode individuals and detecting 98 different nematode genera. We found significant differences in the community structure and functional composition across three farming systems. Extensive grasslands contained the highest nematode abundance, followed by organic vegetable fields, and conventional vegetable fields, indicating a decline due to land-use intensification. Organic farming led to a significant increase in the abundance of herbivores (+82%), bacterivores (+206%) and omnivores (+135%) in comparison with conventional farming. Organic management also enhanced composite (+195%) and herbivores (+451%) footprints, suggesting greater carbon and energy enrichment in soil food web through these functional groups. Community composition of soil nematodes varied significantly across the three farming systems, with each farming system fostering specific indicator taxa. In conclusion, our results show that farming system has a major impact on soil nematode communities with increasing nematode populations under organic vegetable farming. Although organic vegetable production may benefit from enhanced soil fertility due to increased population densities of microbe feeding and omnivorous nematodes, the threat from plant parasitic nematodes to vegetable production requires attention and control strategies should be developed further.

在全世界集约化管理的农业领域中过度使用化肥导致土壤退化和生物多样性丧失。这促使人们对诸如有机农业之类的可持续管理越来越感兴趣。迄今为止，针对常规和有机管理对土壤生物多样性和功能的影响的研究主要集中在可耕种农业上，关于蔬菜生产的报道很少。蔬菜种植特别受到关注，因为管理强度通常很高，并且对蔬菜产品的需求不断增加。土壤线虫是管理土壤生态系统功能的强度的有用指标，因为它们在土壤微食物网中占据多个营养级，并且在养分循环，害虫抑制，以及对微生物群落的监管。在这项研究中，我们评估了管理强度和耕作制度对土壤线虫群落结构和功能行会的影响，比较了瑞士的20个常规蔬菜田，20个有机蔬菜田和20个大草​​原，分析了3万多名线虫个体并检测98个不同的线虫属。我们发现三种农业系统在社区结构和功能组成方面存在显着差异。广泛的草地线虫数量最高，其次是有机菜田和常规菜田，这表明土地利用集约化程度下降。有机耕作导致草食动物的数量大幅增加（+ 82％），与传统耕作相比，细菌含量（+ 206％）和杂食动物（+ 135％）。有机管理还增加了复合材料（+ 195％）和草食动物（+ 451％）的足迹，表明通过这些官能团，土壤食物网中的碳和能量富集度更高。在三种耕作系统中，土壤线虫的群落组成差异很大，每种耕作系统都培育特定的指示性分类单元。总之，我们的结果表明，在有机蔬菜栽培下，随着线虫种群的增加，耕作制度对土壤线虫群落产生了重大影响。尽管由于微生物摄食和杂食性线虫的种群密度增加，有机蔬菜生产可能会从提高土壤肥力中受益，