How do ecological trade-offs drive ectomycorrhizal fungal community assembly? Fine-scale processes with large-scale implications

生态权衡如何驱动外生菌根真菌群落组装？

• 批准号: MR/S017240/1
• 负责人: Filipa Cox
• 金额: $ 83.97万
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=MR%2FS017240%2F1
• 关键词: How; do; ecological; trade; offs

Nearly all plants are associated with mutualistic fungi which inhabit their roots. These mycorrhizal fungi provide the plants with a source of nutrients and in exchange, the plant provides the fungal partner with a source of carbon. Trees typically associate with ectomycorrhizal (ECM) fungi, which are critical to many processes within ecosystems including decomposition and nitrogen and carbon cycling. Different species of ECM fungi can differ in their ability to acquire nutrients or in the suite of functions that they carry out. Understanding what affects the species composition of ECM fungi is therefore important for a better overall understanding of nutrient cycling in soils, forest health, productivity and biodiversity. Individual species of ECM fungi compete for space on the roots of trees. Some fungi are likely to be better competitors for root space than others, but the best competitors are likely to perform less well in other important strategies, such as nutrient acquisition. These 'trade-offs', which mean the ability to perform optimally in one respect is associated with a decline in performance in another, are known to be a fundamental reason why so many species of macro-organisms can co-occur in a single habitat. However, the role that these trade-offs play in affecting mycorrhizal communities is poorly understood despite its probable importance in determining the species composition of these ecologically vital fungi.In this fellowship, I test the hypothesis that trade-offs between nutrient acquisition (the breadth of nitrogen that can be taken up) and competitiveness (the ability to win space on plant roots and obtain plant carbon) is a critical process driving the species of mycorrhizal fungi that can co-occur on individual plant roots, and that this ultimately affects the community composition of fungi observed across landscape-scales. I test this hypothesis using a series of experiments in the laboratory which allow me to trace the quantities of carbon being supplied from the plant to individual species of fungi, and in exchange how much nitrogen is being passed from the fungus to the plant. Field experiments in a forest which has received more than 30 years of experimental nitrogen fertilisation will allow me to test how these trade-offs operate in a more complex natural setting, where the availability of nitrogen may alter the dynamics of the trade-off and the exchange rate of carbon and nitrogen between plant and fungal partner. Finally, I will test how the results observed in the lab and field scale-up to patterns of ECM species occurrence across Europe, using a series of long-term monitoring forest plots.The UK's forests provide significant amenity, carbon-capture and timber value, whilst globally trees form hyper-diverse tropical rainforests, and hold significant stores of carbon in boreal ecosystems. As ECM fungi are a critical component of all tree-dominated ecosystems, the outputs from this project will provide high-quality insights into this key aspect of our natural environment, and help to develop future research, policy and forestry practice in the UK and beyond.

几乎所有的植物都与栖息在其根部的互利共生真菌有关。这些菌根真菌为植物提供营养源，作为交换，植物为真菌伴侣提供碳源。树木通常与外生菌根（ECM）真菌，这是至关重要的生态系统内的许多过程，包括分解和氮和碳循环。不同种类的ECM真菌在获得营养物质的能力或它们执行的功能套件方面可能有所不同。因此，了解影响ECM真菌物种组成的因素对于更好地全面了解土壤中的养分循环、森林健康、生产力和生物多样性至关重要。个别种类的ECM真菌争夺树根上的空间。一些真菌可能比其他真菌更好地竞争根空间，但最好的竞争对手可能在其他重要策略中表现不佳，如养分获取。这些“权衡”，这意味着在一个方面表现最佳的能力与另一个方面的表现下降有关，这是已知的一个根本原因，为什么这么多物种的大型生物体可以共同出现在一个单一的栖息地。然而，这些权衡在影响菌根群落中所起的作用却知之甚少，尽管它在确定这些生态上重要的真菌的物种组成方面可能很重要。我检验了一个假设，即营养获取和（氮的吸收宽度）和竞争力（在植物根上赢得空间并获得植物碳的能力）是驱动可以在单个植物根上共存的菌根真菌物种的关键过程，并且这最终影响在整个植物尺度上观察到的真菌的群落组成。我在实验室里通过一系列实验来验证这个假设，这些实验使我能够追踪从植物向单个真菌物种提供的碳的数量，以及作为交换，有多少氮从真菌传递到植物。在一个已经接受了30多年实验性氮肥的森林中进行的田间实验将使我能够测试这些权衡如何在更复杂的自然环境中运作，在那里氮的可用性可能会改变权衡的动态以及植物和真菌伙伴之间的碳和氮的交换率。最后，我将使用一系列长期监测森林地块，测试如何将实验室和现场观察到的结果扩大到欧洲各地的ECM物种发生模式。英国的森林提供了显着的舒适度、碳捕获和木材价值，而全球树木形成了高度多样性的热带雨林，并在北方生态系统中储存了大量碳。由于ECM真菌是所有以树木为主的生态系统的重要组成部分，该项目的成果将为我们自然环境的这一关键方面提供高质量的见解，并有助于在英国及其他地区发展未来的研究，政策和林业实践。

项目成果

Forest tree growth is linked to mycorrhizal fungal composition and function across Europe.

• DOI: 10.1038/s41396-021-01159-7
• 发表时间: 2022-05
• 期刊: The ISME journal
• 作者: Anthony MA;Crowther TW;van der Linde S;Suz LM;Bidartondo MI;Cox F;Schaub M;Rautio P;Ferretti M;Vesterdal L;De Vos B;Dettwiler M;Eickenscheidt N;Schmitz A;Meesenburg H;Andreae H;Jacob F;Dietrich HP;Waldner P;Gessler A;Frey B;Schramm O;van den Bulk P;Hensen A;Averill C
• 通讯作者: Averill C