Climate change and land-use intensification pose increasing threats to biodiversity, with climate change expected to eventually surpass other global environmental change drivers and become the greatest threat to biodiversity in the future. Understanding the combined ecological impacts of multiple global change drivers is crucial to predict future scenarios of biodiversity change. However, experimental evidence for the impacts of land-use intensification under current and future climate scenarios is lacking, even though this is imperative for understanding future trajectories of biodiversity in agricultural landscapes. We experimentally tested for the simultaneous effects of land-use intensification and climate change on arthropod biodiversity in a field-scale grassland experiment known as the Global Change Experimental Facility (GCEF). Specifically, we tested whether future scenarios of climate change are likely to exacerbate impacts of land-use intensification on arthropod diversity and abundance across different trophic levels by sampling aboveground arthropod communities in low and high land-use intensity grasslands under current and future climatic conditions. We found that climate change reduced total abundances of arthropods and increased evenness of the whole community, while only having trophic level-specific effects on detritivore abundance and evenness. Land-use intensification reduced abundance of the whole community, predators and detritivores, but only eroded species richness of the whole community and herbivores, with the magnitude of declines in predator and detritivore abundance depending on the climate scenario. Additionally, both land-use intensification and climate altered species composition of the whole community and within the predator, herbivore, and detritivore trophic levels. We show that climate change and land use intensification cause simultaneous shifts in arthropod abundance, species richness, and species composition across trophic levels. Changes in arthropod communities as a result of climate change and land-use intensification will likely have profound consequences for ecosystem functioning under future environmental conditions.

气候变化和土地利用集约化对生物多样性构成越来越大的威胁，预计气候变化最终将超越其他全球环境变化驱动因素，成为未来对生物多样性的最大威胁。了解多种全球变化驱动因素的综合生态影响对于预测生物多样性变化的未来情景至关重要。然而，缺乏当前和未来气候情景下土地利用集约化影响的实验证据，尽管这对于理解农业景观中生物多样性的未来轨迹至关重要。我们在称为全球变化实验设施 (GCEF) 的田间草地实验中，通过实验测试了土地利用集约化和气候变化对节肢动物生物多样性的同时影响。具体而言，我们通过在当前和未来气候条件下对低和高土地利用强度草地的地上节肢动物群落进行采样，测试了未来气候变化情景是否可能加剧土地利用集约化对不同营养级节肢动物多样性和丰度的影响。我们发现气候变化减少了节肢动物的总丰度并增加了整个群落的均匀度，而对食腐动物的丰度和均匀度仅具有营养水平特定的影响。土地利用集约化降低了整个群落、捕食者和食腐动物的丰度，但只会侵蚀整个群落和食草动物的物种丰富度，捕食者和食腐动物丰度的下降幅度取决于气候情景。此外，土地利用集约化和气候改变了整个社区以及捕食者、食草动物和食腐动物营养水平的物种组成。我们表明，气候变化和土地利用集约化导致节肢动物丰度、物种丰富度和物种组成在营养水平上同时发生变化。气候变化和土地利用集约化导致的节肢动物群落变化可能会对未来环境条件下的生态系统功能产生深远的影响。