Lewin Amir, Erinjery Joseph J, Nissim Doron, Iwamura Takuya
School of Zoology, Tel Aviv University, Tel Aviv, Israel.
Mitrani Department of Desert Ecology, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Israel.
Ecol Appl. 2023 Apr;33(3):e2804. doi: 10.1002/eap.2804. Epub 2023 Feb 13.
Extensive land conversion to agriculture in drylands and associated resource use have wide-ranging impacts on desert ecosystems globally. Incorporating the impacts of human-social aspects is thus imperative in examining ecological interactions. The provision of agricultural inputs in these resource-scarce regions supports invasive and pest species, negatively impacting both agricultural productivity and native desert ecosystems. Understanding the spatial dynamics of invasive and pest species requires analyzing both bottom-up resource availability factors underlying animal distributions and top-down biological controls. Here, we evaluate the social-ecological cascading effects of dryland agriculture on vertebrate pest communities in dryland agricultural communities of Israel. Our study region is characterized by 18 agricultural cooperatives with distinct crop regimes due to contrasting social decision-making and resource allocation schemes (i.e., communal kibbutzim vs. privatized moshavim). Crop choices further affect land management (e.g., enclosed vs. open farm systems) and resource intensity. This system is ideal for studying trophic mechanisms underlying animal assemblages between agricultural regimes. We examine the role of agricultural land-use practices on pest spatial distributions based on multiyear vertebrate pest observations with agricultural data sets. We use structural equation modeling (SEM) to quantify the relative importance of added agricultural resources underlying bottom-up and top-down trophic processes regulating vertebrate pest assemblages. Results reveal that crop choices determine pest distributions through bottom-up processes directly, while simultaneously driving pest competitive interactions through indirect top-down cascades impacting pest communities. For example, due to the indirect negative effect of wolves on mesopredators (foxes and jackals) mediated by livestock, the total positive effect of livestock on the abundance of mesopredators is reduced. Our study illustrates the social-ecological cascading effects of agricultural regimes on pest community assemblages mediated by contrasting agricultural land-use practices. Considering the expansion of dryland agroecological systems globally, understanding the intricate cascading pathways of predator- and prey-pest communities has important implications for agricultural management, biological invasions in drylands, and fragile desert environments.
旱地大规模转变为农业用地以及相关的资源利用，对全球沙漠生态系统产生了广泛影响。因此，在研究生态相互作用时，纳入人类社会因素的影响势在必行。在这些资源稀缺地区提供农业投入，会助长入侵物种和害虫，对农业生产力和原生沙漠生态系统均产生负面影响。了解入侵物种和害虫的空间动态，需要分析影响动物分布的自下而上的资源可利用性因素以及自上而下的生物控制因素。在此，我们评估了旱地农业对以色列旱地农业社区脊椎动物害虫群落的社会生态级联效应。我们的研究区域由18个农业合作社组成，由于社会决策和资源分配方案不同（即集体基布兹与私有化莫沙夫），作物种植制度各异。作物选择进一步影响土地管理（例如，封闭式与开放式农场系统）和资源强度。该系统是研究不同农业制度下动物群落营养机制的理想选择。我们基于多年来对脊椎动物害虫的观测以及农业数据集，研究农业土地利用实践对害虫空间分布的作用。我们使用结构方程模型（SEM）来量化新增农业资源在调节脊椎动物害虫群落的自下而上和自上而下营养过程中的相对重要性。结果表明，作物选择通过自下而上的过程直接决定害虫分布，同时通过影响害虫群落的间接自上而下级联效应驱动害虫的竞争相互作用。例如，由于狼通过牲畜对中型食肉动物（狐狸和豺狼）产生间接负面影响，牲畜对中型食肉动物数量的总体积极影响降低。我们的研究说明了不同农业土地利用实践介导的农业制度对害虫群落组合的社会生态级联效应。鉴于全球旱地农业生态系统的扩张，了解捕食者与猎物 - 害虫群落复杂的级联路径对农业管理以及旱地生物入侵和脆弱的沙漠环境具有重要意义。
