Data from: Ecological intensification and arbuscular mycorrhizas: a meta-analysis of tillage and cover crop effects

1. Reliance on ecosystem services instead of synthetic, non-renewable inputs is increasingly seen as key to achieving food security in an environmentally sustainable way. This process, known as ecological intensification, will depend in large part on enhancing below-ground biological interactions that facilitate resource use efficiency. Arbuscular mycorrhizas (AM), associations formed between the roots of most terrestrial plant species and a specialized group of soil fungi, provide valuable ecosystem services, but the full magnitude of these services may not be fully realized under conventional intensively-managed annual agricultural systems.

2. Here we use meta-analysis to assess how reducing soil disturbance and periods without roots in agricultural systems affects the formation of AM and the diversity and community composition of arbuscular mycorrhizal fungi (AMF). We compiled data from 54 field studies across five continents that measured effects of tillage and/or cover cropping on AMF colonization and/or communities and assessed effects of management and environmental factors on these responses.

3. Less intensive tillage and winter cover cropping similarly increased AMF colonization of summer annual cash crop roots by ~30%. The key variables influencing the change in AMF colonization were the type of cover crop or the type of alternative tillage, suggesting that farmers can optimize combinations of tillage and cover crops that most enhance AM formation, particularly with no-till systems and legume cover crops.

4. Richness of AMF taxa increased by 11% in low-intensity vs. conventional tillage regimes. Several studies showed changes in diversity and community composition of AMF with cover cropping, but these responses were not consistent.

5. Synthesis and applications. This meta-analysis indicates that less intensive tillage and cover cropping are both viable strategies for enhancing root colonization from indigenous arbuscular mycorrhizal fungi (AMF) across a wide range of soil types and cash crop species, and possibly also shifting AMF community structure, which could in turn increase biologically-based resource use in agricultural systems.

1. 依靠生态系统服务（ecosystem services）而非合成性不可再生投入，正日益被视为以环境可持续方式实现粮食安全的关键所在。这一被称为生态强化（ecological intensification）的过程，在很大程度上依赖于强化地下生物相互作用，以提升资源利用效率。丛枝菌根（arbuscular mycorrhizas, AM）是大多数陆生植物根系与一类特化土壤真菌形成的共生体，能够提供极具价值的生态系统服务，但在常规集约化管理的一年生农业系统中，这些服务的全部潜力可能尚未得到充分发挥。
2. 本研究通过荟萃分析（meta-analysis），评估农业系统中降低土壤扰动与减少无根系时段，会如何影响丛枝菌根（AM）的形成，以及丛枝菌根真菌（arbuscular mycorrhizal fungi, AMF）的多样性与群落组成。我们整合了全球五大洲共54项田间研究的数据，这些研究均探究了耕作方式与/或覆盖种植对AMF定植及/或群落的影响，并分析了管理与环境因子对这些响应的调控作用。
3. 低强度耕作与冬季覆盖种植，均可使夏播一年生经济作物根系的AMF定植率提升约30%，二者效果相当。影响AMF定植率变化的关键变量为覆盖作物类型或替代耕作方式类型，这表明农户可优化耕作与覆盖作物的组合方案，以最大化促进AM形成，其中免耕系统与豆科覆盖作物的组合效果尤为突出。
4. 相较于常规耕作制度，低强度耕作下的AMF分类单元丰富度提升了11%。多项研究显示，覆盖种植会改变AMF的多样性与群落组成，但这类响应并不具备一致性。
5. 综合与应用。本荟萃分析表明，低强度耕作与覆盖种植均为可行策略，可在多种土壤类型与经济作物物种中，提升土著丛枝菌根真菌（indigenous arbuscular mycorrhizal fungi, AMF）对植物根系的定植率，还有望改变AMF的群落结构，进而增强农业系统中基于生物过程的资源利用能力。