Recovery mechanisms of above and belowground diversity and function of grassland, following reduction in intensity of land use: RecovFun

我们需要高效和具有成本效益的生态系统恢复措施，通过土地利用集约化来阻止欧洲草原生物多样性、功能和服务的持续退化。土地利用扩展可能是欧洲草原最直接的恢复办法，因为它遵循这样一种想法，即重建目标参考草原系统的土地利用强度将导致物种丰富的植物群落及其功能和服务的自然恢复。然而，作为对抗草原退化的恢复措施的机制、时间框架和潜在的扩展尚不清楚，限制了政策制定者决定何时将其用作生态系统恢复的工具，以改善草原的多样性和功能，并提供适当的服务。ReCovFun项目提出了一个新的整体框架和新的方法来填补这些知识空白：揭示土地利用扩展作为草原恢复工具的潜力和机制；以及就扩展何时适合恢复草原多样性、营养相互作用、功能和服务提供建立情景和管理指南。为了实现这些目标，人们需要克服三个挑战--RecovFun项目的目标：i)根据一套整体的恢复目标确定扩展潜力；ii)评估扩展对草原多营养多样性、功能和服务的潜在影响的机制；iii)为作为草原恢复工具的管理扩展的最佳效益建立情景和管理指南。初步结果表明，养分循环过程的转变以及植物群落和土壤群落之间的相关相互作用在形成土地利用对草原生态系统的影响方面发挥了核心作用。因此，RecovFUN项目通过量化环境条件的相关变化，即养分、光和微站点可用性，然后评估植物和土壤微生物群落的响应、它们的功能特征和对这些变化的相互作用，并确定其对土壤养分循环和生物量生产的影响，揭示了延伸机制。在生物多样性探索(BE)项目中，草原土地利用减少的新的多地点实验(REX，LUX)将成为评估扩展机制及其作为草原恢复工具的潜力的理想平台。RecovFun对概述的BE目标的主要增值在于：i)有助于从机制上理解土地利用、生物多样性和功能之间的关系，ii)将调查的机制整合到草原恢复的社会文化和利益相关者的背景下，以及iii)通过将已建立的植物-土壤相互作用机制转移到其他有机体群体和相关的功能和服务来提供数据合成机会。

We require efficient and cost-effective ecosystem restoration measures to halt the ongoing degradation of European grasslands' biodiversity, functions, and services through land-use intensification. Land-use extensification might be the directest restoration approach for European grasslands as it follows the idea that re-establishment of land-use intensities of a target reference grassland system will lead to the natural recovery of species-rich plant communities, their functions and services. However, the mechanisms, timeframes, and potential underlying extensification as restoration measure to combat grassland degradation are unclear, limiting the ability of policymakers to decide when its use as a tool for ecosystem restoration to improve grassland diversity, and function, and service provisioning is appropriate. The ReCovFun project proposes a novel holistic framework and novel approaches to fill these knowledge gaps: uncovering the potential and mechanisms of land-use extensification as a grassland restoration tool; and building scenarios and management guidelines of when extensification is suitable to restore grassland diversity, trophic interactions, functioning and service provisioning. To reach these aims one needs to overcome three challenges – the objectives of the RecovFun project: i) identification of extensification potential against a holistic set of restoration goals; ii) assessment of mechanisms underlying extensification effects on grassland multitrophic diversity, functions, and services; and iii) building of scenarios and management guidelines for optimal benefits of management extensification as a grassland restoration tool. Preliminary results highlight, that shifts in nutrient-cycling processes and associated interactions between plant and soil communities play a central role in shaping land-use effects on grassland ecosystems. The RecovFUN project hence uncovers extensification mechanisms by quantifying associated shifts in environmental conditions i.e., nutrient, light, and microsite availability, then assessing responses of plant and soil microbial communities, their functional traits, and interactions to these shifts, and identifying its consequences for soil nutrient cycling and biomass production. The novel multi-site experiments (REX, LUX) of land-use reduction in grasslands within the Biodiversity Exploratories (BE) project will serve as an ideal platform to assess extensification mechanisms and its potential as a grassland restoration tool. The major value-added by RecovFun to the outlined BE aims lies in i) contribution to the mechanistic understanding of relationships between land use, biodiversity, and functioning, ii) integration of investigated mechanisms into the socio-cultural and stakeholder-related context of grassland restoration, and iii) data synthesis opportunities by transferring established mechanisms for plant-soil interactions to other organism groups and associated functions and services.