Influence of sand burial on cultivable micro-fungi inhabiting biological soil crusts
Influence of sand burial on cultivable micro-fungi inhabiting biological soil crusts
复制标题
沙埋对生物土壤结皮中可培养微真菌的影响
DOI：
10.1016/j.pedobi.2015.03.003
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发表时间：
2015-01-01
期刊：
影响因子：
2.3
通讯作者：
Rong, Xin
中科院分区：
文献类型：
--
作者：
Grishkan, Isabella;Jia, Rong Liang;Rong, Xin
研究了腾格里沙漠沙坡头研究站附近0.5 mm和10 mm深的沙埋对苔藓为主和混合生物结皮中微型真菌群落的影响。埋藏的社区进行了比较，在未被掩埋的地壳，以及与桑迪下地壳和表土社区。采用土壤稀释平板法分离到真菌43属65种。与未埋藏的群落相比，埋藏的结皮群落中含黑色素的种类丰度较低，尤其是具有大的多细胞分生孢子的种类，但产生小的浅色单细胞分生孢子的种类丰度较高，主要是中温性青霉属（Penicillium spp.）砂沉积也造成隔离密度的减少，这是更明显的混合结壳。在相同的沙埋水平下，两种结皮类型的微型真菌群落多样性特征和菌株密度存在差异。当群落遭受深沙埋时，混合结皮和苔藓为主的结皮之间的这种差异就不那么明显了。与埋藏结皮相比，结皮下桑迪群落的菌株密度和物种丰富度均显著降低，且结皮下桑迪层的优势种烟曲霉（Aspergillus fumigatus）取代了结皮中具有大型多细胞分生孢子的黑化种。沙埋对结皮微生物群落的影响可能与沙层对蒸发和紫外辐射的屏蔽作用有关。结皮中的泥沙沉积部分改变了土壤微生物的基质质量和小气候条件，而从结皮到结皮下桑迪层的过渡更显著地改变了环境状况（主要是养分状况，从相对丰富的有机结皮层到贫矿物质的桑迪层），从而导致微生物群落发生更显著的变化。(C)2015 Elsevier GmbH. All rights reserved.
We examined the influence of sand burial of 0.5-mm and 10-mm depths on micro-fungal communities inhabiting moss-dominated and mixed biocrusts in the vicinity of the Shapotou Research Station in the Tengger Desert, China. The buried communities were compared with those in unburied crusts, as well as with the sandy below-crust and topsoil communities. We isolated 65 fungal species belonging to 43 genera using the soil dilution plate method. Compared to the unburied communities, the buried crust communities were characterized by lower abundance of melanin containing species, especially those with large many-celled conidia, but higher abundance of species producing small light-colored and one-celled conidia, mainly mesophilic Penicillium spp. Sand deposition also caused reduction of isolate density that was more pronounced in the mixed crusts. Diversity characteristics of micro-fungal communities and isolate densities varied in the two crust types in response to the same level of sand burial. This difference between the mixed and moss-dominated crusts was less expressed when the communities had been subjected to the deep sand burial. Below-crust sandy communities showed a more significant decrease both in isolate density and species richness compared to buried crust communities, which was accompanied by the substitution of dominant species the thermotolerant Aspergillus fumigatus in the subcrust sandy layers instead of melanized species with large multicellular conidia in the crusts. On the whole, the influence of sand burial on crust micro-fungal communities was likely associated with the shielding effect of sand layer which might protect the crust layer from evaporation and UV-radiation. Whereas sand deposition in the crusts partly changed the substrate quality and microclimatic conditions for soil micro-fungi, transition from the crust to the below-crust sandy layer much more substantially altered the environmental situation (mainly in nutrient status, from the comparatively rich organic crust layer to the poor mineral sandy layer) thus leading to the more significant changes in the micro-fungal communities. (C) 2015 Elsevier GmbH. All rights reserved.