SoilBio: Environmental Context Shapes the Benefits of Sustainable Farming on Soil Biodiversity.

Rainfed crops constitute the most extensive agroecosystem on the planet, playing a critical role in supporting food production. Supporting the sustainability of these ecosystems is key to maintain food security in drylands and less developed countries. Soil mesofauna is key to the sustainability and health of agricultural soils due to their role in the processing and recycling of organic matter. Yet, the contribution of agricultural management practices in shaping the diversity and abundance of these organisms remains poorly understood. Here, we investigated the impacts of three contrasting management practices (conventional, organic, and no-till) on the abundance and diversity of soil mesofauna in 291 farms across Spain. Organic and conservation (no-till) agriculture led to greater abundance, richness, and diversity of soil mesofauna compared to conventional management. Both decomposers and predators increased in response to sustainable practices, and Acari was the primary beneficiary mesofauna group. The response of mesofauna to management was modulated by different soil and climatic conditions, with a generally more positive response to sustainable management under more favourable conditions for soil fauna (e.g., higher organic matter content and greater precipitation). Our results highlight the contribution of sustainable management to support soil fauna in agroecosystems. Our findings further indicate the need to apply environmental-context policies to support friendly agriculture that aligns with current long-term sustainability goals and underscore the urgent need to shift away from intensive farming practices before climate change exacerbates environmental degradation.