As an important part of the soil and the ecosystem, soil microbes play an important role in soil formation and development, organic matter decomposition, material transformation and energy transfer, as well as in earth biochemical cycle and bioremediation. The role of soil microbes in environment, or in other words, the functional diversity of microorganisms, is mainly achieved through a variety of metabolic and physiological functions. Therefore, microbial diversity can be considered as an important indicator for assessing soil changes caused by natural or man-made disturbances. Because microbes have such an obvious effect on ecosystems, studying them will have far-reaching implications. In recent years, the vulnerability of ecosystem in some places has attracted much attention from researchers. Wetland, for example, soil microbes have been quite vital for the improvement of its stability.

As for the geographical regularity of distribution and the response of salt vegetation succession, the microbes’ structure are the hotspots in recent years.

A study has been made to investigate the point. A typical wetland that represents the native succession process of vegetation is selected.

From the distance to the coastline, the plant community order is saline-alkali land → saline seepweed community → tamarix community →angiospermae community → apocynum community → imperata cylindrica (L.) beauv community → cotton community. The soil physical and chemical properties under the 0-20cm depth of vegetation were studied by measuring soil moisture content, electrical conductivity, active organic matter, water-soluble phosphorus, humus, alkali nitrogen, catalase and urease. The high-throughput sequencing technology was used to sequence the micro-organisms in the soil under different vegetations (microbial identification). Results found that soil microbes were composed of combination in the gate, class, order, family and genus. All over 30,000 sequences belong to 17 gates, including Proteobacteria, Bacteroidetes, Actinobacteria, Planctomyctes, d Firmicutes, Acidobacteria, Chloroflexi, and Verrucomicrobia, accounting for 44.67%, 7.05%, 9.2%, 2.16%, 2.15%, 6.36% 1.70%, 1.07%, respectively. Among them, the sequence of Proteobacteria, Bacteroidetes, Actinobacteria, and Acidobacteria constitutes 67.28%, which shows their domain features.

This indicates the similarity of the microbial population in the same habitat, despite the different sampling locations. However, the main soil microbial community structures at different vegetation types are also significantly different. By studying the effects of vegetation under different successions on soil microbial community structure, the relative abundances of Proteobacteria, Actinobacteria and Acidobacteria were significantly different, and Proteobacteria was the dominant group. Under heavy salt stress, the relative abundances of Chloroflexi, Bacteroidetes and Acidobacteria were significantly different. Under light salt stress, the relative abundances of Proteobacteria, Chloroflexi, Bacteroidete and Acidobacteria were significantly different. Under the cultivation, the relative abundance of Proteobacteria and Bacteroidetes decreased compared with the Imperata cylindrica (L.) Beauv, which indicated that there were other factors affecting the soil microbial community structure in addition to the salt content. Calculation was performed to find out the biodiversity index of soil microorganisms with specific formula. And the results revealed that the bacterial diversity in the soil of saline seepweed is relatively the least, and increases with growing coverage of vegetation. By studying the relative abundance and microbial diversity index of soil microbial physicochemical properties, urease activity and soil humus were the main factors affecting soil microbial relative abundance and microbial diversity.

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CD Genomics is committed to providing novel NGS services enabling researchers to explore structure and function of microbial community in a high-resolution and culture-independent manner using technology from Illumina and PacBio. In addition, we also offer the service to sequence the genome of the individual cultured bacteria, fungi, phage or virus, whether do novo or re-sequencing.