PDF(Pubmed)
Abstract：
Biological soil crusts, or biocrusts, are microbial communities found in soil surfaces in drylands and in other locations where vascular plant cover is incomplete. They are functionally significant for numerous ecosystem services, most notably in the C fixation and storage due to the ubiquity of photosynthetic microbes. Whereas carbon fixation and storage have been well studied in biocrusts, the composition, function and characteristics of other organisms in the biocrust such as heterotrophic bacteria and especially fungi are considerably less studied and this limits our ability to gain a holistic understanding of biocrust ecology and function. In this research we characterised the fungal community in biocrusts developed on Kalahari Sand soils from a site in southwest Botswana, and combined these data with previously published bacterial community data from the same site. By identifying organisational patterns in the community structure of fungi and bacteria, we found fungi that were either significantly associated with biocrust or the soil beneath biocrusts, leading to the conclusion that they likely perform functions related to the spatial organisation observed. Furthermore, we showed that within biocrusts bacterial and fungal community structures are correlated with each other i.e., a change in the bacterial community is reflected by a corresponding change in the fungal community. Importantly, this correlation but that this correlation does not occur in nearby soils. We propose that different fungi engage in short-range and long-range interactions with dryland soil surface bacteria. We have identified fungi which are candidates for further studies into their potential roles in biocrust ecology at short ranges (e.g., processing of complex compounds for waste management and resource provisioning) and longer ranges (e.g., translocation of resources such as water and the fungal loop model). This research shows that fungi are likely to have a greater contribution to biocrust function and dryland ecology than has generally been recognised.
摘要：
生物土壤结壳，或者生物火山灰，是在旱地土壤表面和维管植物覆盖不完整的其他地方发现的微生物群落。它们对许多生态系统服务具有重要的功能，由于光合微生物的普遍存在，最值得注意的是C固定和储存。尽管碳固定和储存在生物锈病中已经得到了很好的研究，组成,生物中其他生物的功能和特征，例如异养细菌，尤其是真菌的研究要少得多，这限制了我们对生物的生态学和功能的全面了解。在这项研究中，我们对博茨瓦纳西南部喀拉哈里沙土上形成的生物锈菌中的真菌群落进行了表征，并将这些数据与以前发布的来自同一地点的细菌群落数据相结合。通过确定真菌和细菌群落结构的组织模式，我们发现真菌与生物锈病或生物锈病下的土壤密切相关，得出的结论是，它们可能执行与观察到的空间组织相关的功能。此外，我们表明，在生物锈菌中，细菌和真菌群落结构是相互关联的，即，细菌群落的变化反映在真菌群落的相应变化上。重要的是,这种相关性，但这种相关性不会发生在附近的土壤中。我们建议不同的真菌与旱地土壤表面细菌进行短程和远程相互作用。我们已经确定了真菌，这些真菌是进一步研究它们在短距离生物生态学中的潜在作用的候选者（例如，处理用于废物管理和资源供应的复杂化合物)和更长的范围(例如，水和真菌循环模型等资源的易位)。这项研究表明，真菌对生物功能和旱地生态的贡献可能比一般公认的要大。
