Functional diversity of mycorrhiza in relation to land-use changes and ecosystem functions / Code ECTOMYC

ECTOMYC项目针对森林管理中外生菌根真菌群落的物种丰富度和生态系统功能。我们确定了土壤pH值，森林管理强度，树种和根养分含量的重要驱动因素的根相关真菌群落的结构。使用稳定同位素（15 NO3-，15 NH 4+），我们发现，不同的外生菌根真菌物种不同强烈的氮富集，这表明在底物的使用有很大差异。根相关的真菌组合在所有的森林实验地块在Exploratories的结构分析表明，氮解释了显着的一部分根相关的真菌组合的变化。这些结果表明，真菌的养分利用特性有助于生态系统动态。实验方法，以获得信息外生菌根真菌在田间条件下的基板偏好是稀缺的。 根据前几个阶段的成果，该项目的具体目标是： 解剖根相关真菌组合的时间和空间营业额根据生态组（共生，saprotroph，pathotroph）和他们的主要驱动因素（土地利用，气候，非生物土壤条件，根营养）。（二） 通过诱饵试验研究真菌的营养利用特性（iii） 为了建立森林管理措施（树木砍伐和林隙形成）与根际真菌的功能和组成以及根系营养生理之间的因果关系，我们将在生物多样性探索中心的150个森林样地中采集根系样本，并利用2014年、2017年和2020年的结果调查根系真菌的时空变化。在诱饵实验中，真菌菌丝可进入的网状容器将补充基质，并研究定殖真菌群落。砍伐树木会影响土壤中碳的分配。我们将使用新的森林实验（树木切割）调查根系碳生理变化的影响，相关的外生菌根，腐生性和其他真菌群体的结构和反馈树矿物质营养。这些结果将有助于提高我们对生态系统功能的理解。

The project ECTOMYC addresses species richness and ecosystem functions of ectomycorrhizal fungal assemblages in response to forest management. We identified soil pH, forest management intensity, tree species and root nutrient contents as important drivers of the structure of root-associated fungal communities. Using stable isotopes (15NO3-, 15NH4+), we found that different ectomycorrhizal fungal species differed strongly in nitrogen enrichment, suggesting large differences in substrate use. Analyses of the structure of root-associated fungal assemblages across all forest experimental plots in the Exploratories revealed that nitrogen explained a significant portion of the variation in root-associated fungal assemblages. These results suggest that fungal traits for nutrient use contribute to ecosystem dynamics. Experimental approaches to obtain information on substrate preferences of ectomycorrhizal fungi under field conditions are scarce. Based on the results of the previous phases, the specific aims of this project are:(i) to dissect temporal and spatial turnover of root-associated fungal assemblages according to ecological groups (symbiotroph, saprotroph, pathotroph) and their main drivers (land use, climate, abiotic soil conditions, and root nutrients).(ii) to investigate fungal traits for nutrient use by bait experiments (iii) to establish causal relationships between forest management measures (tree cutting and gap formation) between the function and composition of root-associated fungi and root nutrient physiology.To achieve these goals, we will sample roots in 150 forest plots of the Biodiversity Exploratories and use the results from 2014, 2017 and 2020 to investigate spatiotemporal variation of fungi on roots. In bait experiments, mesh containers accessible for fungal hyphae, will be supplemented with substrates and the colonizing fungal community will be studied. Tree cutting affects carbon allocation to the soil. We will use the new forest experiment (tree cutting) to investigate the impact of changes in root carbon physiology on the structure of associated ectomycorrhizal, saprotrophic and other fungal groups and the feedback for tree mineral nutrition. These results will contribute to increase our understanding of ecosystem functioning.