REstoration and prognosis of PEAT formation in fens. Linking diversity in plant functional traits to soil biological and biogeochemical processes

地下生物多样性是由真菌、细菌、古生菌、动植物共同影响土壤功能形成的，特别是通过控制有机物质的产生和分解速度。泥炭土壤是土壤碳最集中的储存地，它是由长期净生产量超过腐解量形成的。在欧洲，大多数泥炭地，特别是沼泽，都严重退化。人们对决定泥炭形成和相关生态系统服务以及生物多样性在重新湿化后是否真正恢复的驱动因素和途径知之甚少。以前的研究集中在雨水灌溉的沼泽和向上生长的泥炭。在地下水灌溉的沼泽中，莎草的根生长到较老的泥炭中，形成置换泥炭。Repeat旨在通过将生物地球化学过程与土壤群落结构和生物多样性以及植物地下特征联系起来，阐明沼泽中泥炭形成的机制。为减缓气候变化、区域水文学、养分保持和生物多样性提供重要生态系统服务的恢复和沼泽养殖(生物量收获)受到特别关注。主要的研究问题是：环境因素和人类管理如何与土壤生物多样性相互作用，以确定未排水和重新湿润的沼泽中泥炭的积累速率？这个项目是第一个利用跨学科、多方法和多地点的方法系统地研究沼泽泥炭形成的项目，沼泽泥炭形成是温带的主要机制。它重点关注受干扰最少和受干扰最严重的FEN，并调查后者的可恢复性，同时涵盖所有主要的欧盟FEN地区。为了比较未排水、排水和复湿沼泽，我们现场分析了四个国家的生态系统过程，并辅之以异地中观和实验室实验。该项目分为8个工作包(协调和管理、国家变量、泥炭堆积率、分解者多样性、生产者多样性、建模、科学集成、外联)。在欧盟，从2021年起，必须强制计算来自大多数排水沼泽的温室气体通量，这将促进泥炭地的重新湿润。泥炭地恢复也响应了欧盟2020年生物多样性战略和CBD爱知目标。迫切需要就生物多样性驱动的碳固存和生态系统复原力机制提供指导。参与国的利益攸关方将通过讲习班、会外活动和实地日融入其中。确定了欧盟、国家和地区级别的最终用户。一个关键的利益攸关方(湿地国际)作为财团合作伙伴参与其中。该项目将推进以流程为导向的FEN修复的知识库，并将直接影响相关政策的实施。Repeat将整合覆盖欧洲最重要沼泽地区的五个机构的泥炭地生态专业知识，以获得泥炭形成过程中最先进的知识。

Belowground biodiversity is formed by fungi, bacteria, archaea, animals and plants that altogether affect soil functioning, particularly by controlling rates of production and decomposition of organic matter. Peat soils, being the most concentrated stores of soil carbon, are formed by a long-term net exceedance of production over decomposition. In Europe most peatlands, especially fens, are severely degraded. Little is known about drivers and pathways that determine whether peat formation and related ecosystem services and biodiversity are truly reinstated after rewetting. Previous research has focused on rainwater-fed bogs with upward growing peatmoss. In groundwater-fed fens roots of sedges grow into the older peat to form displacement peat. REPEAT aims to clarify the mechanisms of peat formation in fens by linking biogeochemical processes to soil community structure and biodiversity, as well as to plant belowground traits. Restoration and paludiculture (biomass harvest) providing vital ecosystem services for mitigation of climate change, regional hydrology, nutrient retention and biodiversity receive special attention. The main research question is: How do environmental factors and human management interact with soil biodiversity in determining rates of peat accumulation in undrained and rewetted fens? This project is the first to systematically address fen peat formation, the predominant mechanism of the temperate zone, using an interdisciplinary, multi-method and multi-site approach. It focuses on both the least disturbed and the most disturbed fens and investigates the restorability of the latter ones, while covering all major EU fen regions. To compare undrained, drained and rewetted fens, we analyse ecosystem processes in-situ in four countries, supplemented by ex-situ mesocosm and laboratory experiments. The project is organised in 8 work packages (Co-ordination and management, State variables, Peat accumulation rates, Decomposers diversity, Producers diversity, Modelling, Scientific integration, Outreach). In the EU, GHG fluxes from most drained fens must be mandatorily accounted from 2021 onwards, which will boost peatland rewetting. Peatland restoration responds also to the EU Biodiversity Strategy 2020 and the CBD Aichi Goals. Guidance on biodiversity-driven mechanisms of carbon sequestration and ecosystem resilience is urgently needed. Stakeholders in participating countries will be integrated through workshops, side events, and field days. Endusers at the EU, national, and regional level are identified. A key stakeholder (Wetlands International) is involved as a consortium partner. The project will advance the knowledge base for process-oriented restoration of fens and will directly impact the application of related policy. REPEAT will consolidate the peatland ecology expertise of five institutions covering the most important European fen regions to obtain the best state-of-the-art knowledge fen peat formation processes.