Drylands soil bacterial community is affected by land use change and different irrigation practices in the Mezquital Valley, Mexico

Abstract

Dryland agriculture nourishes one third of global population, although crop irrigation is often mandatory. As freshwater sources are scarce, treated and untreated wastewater is increasingly used for irrigation. Here, we investigated how the transformation of semiarid shrubland into rainfed farming or irrigated agriculture with freshwater, dam-stored or untreated wastewater affects the total (DNA-based) and active (RNA-based) soil bacterial community composition, diversity, and functionality. To do this we collected soil samples during the dry and rainy seasons and isolated DNA and RNA. Soil moisture, sodium content and pH were the strongest drivers of the bacterial community composition. We found lineage-specific adaptations to drought and sodium content in specific land use systems. Predicted functionality profiles revealed gene abundances involved in nitrogen, carbon and phosphorous cycles differed among land use systems and season. Freshwater irrigated bacterial community is taxonomically and functionally susceptible to seasonal environmental changes, while wastewater irrigated ones are taxonomically susceptible but functionally resistant to them. Additionally, we identified potentially harmful human and phytopathogens. The analyses of 16 S rRNA genes, its transcripts and deduced functional profiles provided extensive understanding of the short-term and long-term responses of bacterial communities associated to land use, seasonality, and water quality used for irrigation in drylands.

Dead or Alive; or Does It Really Matter? Level of Congruency Between Trophic Modes in Total and Active Fungal Communities in High Arctic Soil

“…Differences in the explanatory power of environmental variables between rDNA and rRNA-based community compositions have been reported only in a few studies comparing outcomes from both metabarcoding templates (i.e., Barnard et al, 2013; Zhang et al, 2014; Lüneberg et al, 2018). Yet it seems important to understand which parameters are crucial for shaping the community composition.…”

Microbial Community Structure and Functionality in the Deep Sea Floor: Evaluating the Causes of Spatial Heterogeneity in a Submarine Canyon System (NW Mediterranean, Spain)

“…The numeric results represent a fraction of the community that matched with the functional database, and indicate the community proportions containing each specific function. We filtered a total of 106 KEGGs (functional orthologs) within 30 metabolic pathways (Llorens-Marès et al, 2015), including five additional phosphorous cycle pathways (G-3-P transport, phosphate transport -high and low efficiency-, phosphonate transport, and phosphonate metabolism) (Vila-Costa et al, 2013), and four complex OM decomposition pathways (chitin, cellulose, hemicellulose, and lignin) (Lüneberg et al, 2018).…”

Effect of treated wastewater irrigation on physiological and agronomic properties of beans Vicia faba

“…However, this can obviously affect normal development of plants and functional properties of soils receiving this nonconventional water. Moreover, many studies have been assessed the effect of TWW reuse on soils, plants and soil organisms [50,51,52,53,54,55] and in most cases they found that those effluent modify the physicochemical properties of soils, and physiological properties of plants and other organisms.…”