Many woody and herbaceous plants in temperate forests cannot establish and survive in the absence of mycorrhizal associations. Most temperate forests are dominated by ectomycorrhizal woody plant species, which implies that the carrying capacity of the habitat for arbuscular mycorrhizal fungi (AMF) is relatively low and AMF could in some cases experience a limitation of propagules. Here we address how the AMF community composition varied in a small temperate forest site in Germany in relation to time, space, two plant host species, and also with regard to the degree to which plots were covered with AMF-associating woody species. The AMF communities in our study were non-random. We observed that space had a greater impact on fungal community composition than either time, mycorrhizal state of the close-by woody species, or the identity of the host plant. The identity of the host plant was the only parameter that modified AMF richness in the roots. The set of parameters which we addressed has rarely been studied together, and the resulting ranking could ease prioritizing some of them to be included in future surveys. AMF are crucial for the establishment of understory plants in temperate forests, making it desirable to further explore how they vary in time and space.

在没有菌根关联的情况下，温带森林中的许多木本和草本植物无法建立和生存。大多数温带森林以外生菌根木本植物为主，这意味着丛枝菌根真菌 (AMF) 栖息地的承载能力相对较低，并且在某些情况下 AMF 可能会受到繁殖体的限制。在这里，我们讨论了 AMF 群落组成如何在德国的一个小型温带森林中与时间、空间、两种植物宿主物种以及地块被 AMF 相关木本物种覆盖的程度有关。我们研究中的 AMF 社区是非随机的。我们观察到空间对真菌群落组成的影响比任何时候都大，附近木本物种的菌根状态，或寄主植物的身份。寄主植物的身份是改变根中 AMF 丰富度的唯一参数。我们讨论的这组参数很少被一起研究，由此产生的排名可以轻松地将其中一些参数优先包含在未来的调查中。AMF 对于在温带森林中建立林下植物至关重要，因此有必要进一步探索它们在时间和空间上的变化。