Cardiff School of Biosciences, Cardiff University, Museum Avenue, Cardiff, CF10 3AX, UK.
Ecol Lett. 2011 Nov;14(11):1134-42. doi: 10.1111/j.1461-0248.2011.01682.x. Epub 2011 Sep 19.
Saprotrophic fungal community composition, determined by the outcome of competitive mycelial interactions, is one of the many key factors affecting soil nutrient mineralisation and decomposition rates. Fungal communities are not generally predicted to be regulated by top-down factors, such as predation, but rather by bottom-up factors, including resource availability. We show that invertebrate grazers can exert selective pressures on fungal decomposer communities in soil, reversing the outcomes of competitive interactions. By feeding selectively on the cord-forming fungus Resinicium bicolor, isopods prevented the competitive exclusion of Hypholoma fasciculare and Phanerochaete velutina in soil and wood. Nematode populations also reversed the outcomes of competitive interactions by stimulating growth of less competitive fungi. These represent two opposing mechanisms by which soil fauna may influence fungal community composition and diversity. Factors affecting soil invertebrate communities will have direct consequences for fungal-mediated nutrient cycling in woodland soils.
腐生真菌群落组成取决于竞争菌丝体相互作用的结果，是影响土壤养分矿化和分解速率的众多关键因素之一。一般来说，真菌群落不受捕食等自上而下因素的调节，而是受资源可用性等自下而上因素的调节。我们表明，土壤中的无脊椎食草动物可以对真菌分解者群落施加选择性压力，从而改变竞争相互作用的结果。等足目动物通过选择性地取食卷须状真菌 Resinicium bicolor，阻止了 Hypholoma fasciculare 和 Phanerochaete velutina 在土壤和木材中的竞争排除。线虫种群也通过刺激竞争力较弱的真菌生长来改变竞争相互作用的结果。这代表了两种相反的机制，土壤动物可以通过这些机制影响真菌群落组成和多样性。影响土壤无脊椎动物群落的因素将直接影响林地土壤中真菌介导的养分循环。
