Department of Environmental Science, University of Arizona, Tucson, AZ, 85721, USA.
Environ Microbiol. 2022 Sep;24(9):4094-4107. doi: 10.1111/1462-2920.15998. Epub 2022 May 3.
In arid ecosystems, where the soil is directly exposed to the action of the wind due to sparse vegetation, dust aerosolization is a consequence of soil degradation and concomitantly, a major vector of microbial dispersal. Disturbances such as livestock grazing or fire can exacerbate wind erosion and dust production. Here, we sampled surface soils in 29 locations across an arid landscape in southwestern USA and characterized their prokaryotic and fungal communities. At four of these locations, we also sampled potential fugitive dust. By comparing the composition of soil and dust samples, we determined the role of dust dispersal in structuring the biogeography of soil microorganisms across the landscape. For Bacteria/Archaea, we found dust associated taxa to have on average, higher regional occupancies compared to soil associated taxa. Complementarily, we found dust samples to harbour a higher amount of widely distributed taxa compared to soil samples. Overall, our study shows how dust dispersal plays a role in the spatial distribution of soil Bacteria/Archaea, but not soil Fungi, and might inform indicators of soil health and stability in arid ecosystems.
在干旱生态系统中，由于植被稀疏，土壤直接受到风的作用，尘土飞扬是土壤退化的结果，同时也是微生物传播的主要载体。牲畜放牧或火灾等干扰会加剧风蚀和尘土产生。在这里，我们在美国西南部的干旱景观中 29 个地点采集了表层土壤样本，并对其原核生物和真菌群落进行了特征描述。在其中四个地点，我们还采集了潜在的飞扬尘。通过比较土壤和灰尘样本的组成，我们确定了灰尘扩散在整个景观中土壤微生物生物地理学结构中的作用。对于细菌/古菌，我们发现与灰尘相关的分类群的平均区域占有率高于与土壤相关的分类群。补充地，我们发现与土壤样本相比，灰尘样本中含有更多广泛分布的分类群。总的来说，我们的研究表明灰尘扩散如何在土壤细菌/古菌的空间分布中发挥作用，但对土壤真菌没有影响，这可能为干旱生态系统中的土壤健康和稳定性指标提供信息。
