Saudi Arabia has the world's fifth-largest desert and is the biggest importer of food and agricultural products. Understanding soil microbial communities is key to improving the agricultural potential of the region. Therefore, soil microbial communities of the semiarid region of Abha, known for agriculture, and arid regions of Hafar Al Batin and Muzahmiya were studied using Illumina sequencing. The results show that the microbial communities of the Saudi desert were characterized by the presence of high numbers of Actinobacteria, Proteobacteria, and Firmicutes. In addition to Sahara desert signature phyla like Gemmatimonadetes, biogeochemically important microorganisms like primary producers, nitrogen fixers and ammonia oxidizers were also present. The composition of the microbial community varied greatly among the sites sampled. The highest diversity was found in the rhizospheric soil of Muzahmiya followed by Abha. Firmicutes, Proteobacteria and Actinobacteria were the three main phyla detected in all the samples. Soils from the agricultural region of Abha were significantly different from other samples in containing only 1 % Firmicutes and 3–6 times higher population of Actinobacteria and Bacteroidetes, respectively. The presence of photosynthetic bacteria, ammonia oxidizers, and nitrogen fixers along with bacteria capable of surviving on simple and unlikely carbon sources like dimethylformamide was indicative of their survival strategies under harsh environmental conditions in the arid soil. Functional inference using PICRUSt analysis shows an abundance of genes involved in photosynthesis and nitrogen fixation.

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沙特阿拉伯干旱土壤中的微生物群落及其预测功能特征

沙特阿拉伯是世界第五大沙漠，是最大的食品和农产品进口国。了解土壤微生物群落是提高该地区农业潜力的关键。因此，使用Illumina测序研究了以农业闻名的Abha半干旱地区和Hafar Al Batin和Muzahmiya干旱地区的土壤微生物群落。结果表明，沙特沙漠的微生物群落的特征是存在大量的放线菌，变形杆菌和菌丝。除了撒哈拉沙漠特征种（如Gemmatimonadetes）外，还存在生物地球化学重要的微生物，如主要生产者，固氮剂和氨氧化剂。在采样点之间，微生物群落的组成差异很大。在Muzahmiya的根际土壤中发现的多样性最高，其次是Abha。硬毛菌，变形杆菌和放线菌是在所有样品中检测到的三个主要门。艾卜哈（Abha）农业地区的土壤与其他样品相比有显着不同，分别只含有1％的硬毛菌和高3-6倍的放线菌和拟杆菌。光合细菌，氨氧化剂和固氮剂的存在以及能够在简单且不太可能的碳源（如二甲基甲酰胺）上存活的细菌，表明了它们在干旱土壤中的恶劣环境条件下的生存策略。使用PICRUSt分析进行功能推论表明，有大量基因参与光合作用和固氮。