Prokaryotic Community Distribution along an Ecological Gradient of Salinity in Surface and Subsurface Saline Soils

Abstract

Salinity effects on microbial communities in saline soils is still unclear, and little is known about subsurface soil microbial communities especially in saline or hypersaline ecosystems. Here we presented the survey of the prokaryotic community in saline soils along a salinity gradient (17.3–148.3 dS/m) in surface (0–10 cm) and subsurface (15–30 cm) saline soils of Qarhan Salt Lake, China. Moreover, we compared them with three paired nonsaline normal soils. Using the high-throughput sequencing technology and several statistical methods, we observed no significant community difference between surface soils and subsurface soils. For environmental factors, we found that TOC was the primary driver of the prokaryotic community distribution in surface saline soils, so was pH in subsurface saline soils. Salinity had more effects on the prokaryotic community in subsurface saline soils than in surface saline soils and played a less important role in saline soils than in saline waters or saline sediments. Our research provided references for the prokaryotic community distribution along a salinity gradient in both surface and subsurface saline soils of arid playa areas.

Metagenomic Insights into the Phylogenetic and Metabolic Diversity of the Prokaryotic Community Dwelling in Hypersaline Soils from the Odiel Saltmarshes (SW Spain)

“…These soils were classified as sandy loam according to USDA textural classification system. Organic carbon content was in the range of the values reported for saline soils of La Sal del Rey (Edinburg, TX, USA) [ 18 ] and Sicily (Italy) [ 10 ], but lower than those found in saline soils of Qarhan Salt Lake (China) [ 5 ]. Nitrogen contents of the studied mineral soils are similar to those of the study of Hollister et al [ 18 ] and Pandit et al [ 19 ].…”

“…However, with that in mind, we attempted to situate our study in the context of the available literature about saline soils microbiota, using proposed conversions when necessary [ 65 ]. We found that the soils considered in our study were in the range of the saline soils studied by Xie et al from Qarhan Salt Lake (China) [ 5 ] and highest salinity soils addressed by Hollister et al [ 18 ], Canfora et al [ 10 ], Pandit et al [ 19 ] and Navarro-Noya et al [ 14 ] from La Sal del Rey (Edinburg, TX, USA), Sicily, the Great Rann of Kutch desert (Gujarat, India) and the former Lake Texcoco (Mexico), respectively.…”

“…These environments include saline lakes, marine salterns, salted foods, deep-sea brine pools and saline soils and sediments [ 2 ]. While extensive studies have been performed on aquatic hypersaline habitats [ 2 , 3 , 4 ], other saline environments such as soil systems have been much less thoroughly investigated [ 5 ].…”

“…Despite the economic, environmental, and nutritional consequences of the increasing rate of soil salinization, microbial biodiversity studies of saline soils are scarce [ 8 ]. Furthermore, the few available studies focused on either bacteria [ 9 , 10 , 11 , 12 , 13 ] or archaea [ 14 , 15 , 16 , 17 ], but rarely on both domains [ 5 , 18 , 19 , 20 ], which has led to a partial and incomplete view of the phylogenetic diversity and potential microbial processes carried out in these soils. Overall, our current aquatic-biased knowledge about halophilic microorganisms and their environments, and the limited data available from saline soil studies, impair our ability to make knowledge-based predictions of the effects of the increasing salinization of soils as well as to direct management and rehabilitation plans.…”

Macro and Microelements Drive Diversity and Composition of Prokaryotic and Fungal Communities in Hypersaline Sediments and Saline–Alkaline Soils

“…Microbial communities are ubiquitous and can even thrive in extreme environments such as hypersaline lakes, marine habitats and saline–alkaline soils ( Jiang et al, 2007 ; Andrei et al, 2015 ; Yakimov et al, 2015 ; Xie et al, 2017 ). They are key components of these extreme ecosystems, and thus play central roles in their geochemical cycles and ecological stability ( Nunoura et al, 2013 ; Liang et al, 2014 ; Sorokin et al, 2015 ).…”