We studied the effect of plant canopy on the distribution of microfungi through 0−30-cm soil profiles under canopies of three plant species and in their adjacent interspace at sun-exposed plain and north-facing slope in the Tabernas Desert, Spain. Using the soil dilution plate method, 142 species from 68 genera were isolated. Melanin-containing fungi dominated in the topsoil layers because of high temperatures and dryness. By contrast, light-colored fungi generating a high amount of small thin-walled conidia substantially increased their abundance in the deeper soil layers – thermotolerant Aspergillus spp. in the 1−5-cm layers and mesophilic Penicillium spp. in the 10−20-cm layers. The significant increase in density of microfungal isolates at 1−10 cm-depth could be associated with the deposition of conidia of aspergilli and penicillii caused by shallow water infiltration in the fine-grained soil and their survival at these depths due to more appropriate edaphic conditions (mainly higher water availability and root concentration). Generally, the effect of plant canopy on microfungal communities was only weakly expressed in higher variations of isolate densities and species richness through the profiles, and in reduced abundance of melanized species with protective multicellular spore morphology in the topsoil layers; at the same time, soil depth strongly influenced all community characteristics. The study highlights the remarkable role of edaphic factors (temperature, water regime, and soil texture) in the distribution of microfungi through soil depth in semi-arid areas.

我们研究了西班牙塔贝纳斯沙漠中暴露于阳光的平原和朝北斜坡上三种植物物种的冠层及其相邻空间中植物冠层对0-30 cm土壤剖面中微真菌分布的影响。使用土壤稀释板法，从68属中分离出142种。由于高温和干燥，含黑色素的真菌在表土层占主导地位。相比之下，浅色真菌会产生大量小的薄壁分生孢子，从而大大增加了土壤深层（耐热曲霉属）的丰度。在1-5 cm的层和中温青霉spp。在10-20厘米的层中 在1-10 cm深度处，微真菌分离物的密度显着增加可能与细粒土壤中浅水渗透引起的曲霉和青霉分生孢子的沉积及其在更深的土壤条件下在这些深度的存活有关（主要是较高的水利用率和根系浓度）。一般而言，植物冠层对微真菌群落的影响仅通过分布图上的分离物密度和物种丰富度的较高变化以及表层土壤中具有保护性多细胞孢子形态的黑色素物种的丰度降低而微弱地表达。同时，土壤深度强烈影响了所有群落特征。这项研究强调了营养因素（温度，水分状况，