Bacterial community composition in costal dunes of the Mediterranean along a gradient from the sea shore to the inland

Abstract

Sand dunes are unique ecosystems with distinct features which limited the accumulation of biomass. The distance from seashore affects both the physical properties of the sand dunes and the biota living above- and below ground. The goal of the present study was to determine the effects of the distance from shore to inland on soil bacterial community composition during wet and dry season. We studied a chronosequence of sites close to the eastern Mediterranean coast. Bacterial diversity was assessed using directly extracted DNA from soil samples and 16 S ribosomal RNA gene fingerprinting. Our data indicates a significant influence of season and site on bacterial community structure. We showed that during the wet season soil organic matter, pH and salinity strongly influence bacterial community composition, whereas during the dry period bacterial diversity was mainly driven by the shortage of water at all sites. Consequently diversity was lowest during dry season at dunes close to the shore, whereas during the wet season the higher water content and the reduced salinity at the dunes which are more at the inland induced an increase in diversity, which illustrates the pronounced dynamics of microbial communities in soil over a season mainly at inland dunes.

Microbial community composition in alpine lake sediments from the Hengduan Mountains

“…Harsh conditions such as low temperatures, high ultraviolet radiation, and low concentrations of dissolved organic carbon and oligotrophy are characterized in these alpine environments (Čuperová, Holzer, Salka, Sommaruga, & Koblízek, ; Rose, Williamson, Saros, Sommaruga, & Fischer, ; Seufferheld, Alvarez, & Farias, ). These harsh conditions alter the hydrology and structure of the lake and may affect the microbial community composition and biogeochemical functions (Liu et al., ; Rose et al., ; Wasserstrom et al., ). Since alpine lakes have been reported to be early indicators of environmental change, the function of microorganisms in the related processes has attracted new research interest (Shafi, Kamili, Shah, Parray, & Bandh, ).…”

The Response of Soil CO2 Efflux to Water Limitation Is Not Merely a Climatic Issue: The Role of Substrate Availability

“…In the present study, CLPP and EL-FAME revealed a dynamic assemblage of microbial communities, as could be expected under seasonal drought cycles [30,67]. However, SDS revealed a more plastic and opportunistic behaviour of microbial community than the WDS.…”

Soil ecology of the exotic dune grass Leymus arenarius.

“…Leymus populations were generally near the first dune ridge, but even within this constrained sampling, we found dune successional position to be important. A recent study by Wasserstrom et al (2017) also found landscape position to be important for structuring soil bacterial communities in dune systems, with lowest bacterial diversity on the youngest dunes, closest to the water.…”

“…Previous work has shown that altered precipitation can alter bacterial community structure and function (Barnard et al 2015;Fuchslueger et al 2014;Papatheodorou et al 2004;Zeglin et al 2013). These changes in the bacterial community can vary over relatively short time frames (Cregger et al 2012;Papatheodorou et al 2004;Wasserstrom et al 2017). In an old-field system, manipulations of precipitation to mimic patterns of climate change reveal strong shifts in community composition, primarily among Proteobacteria and Acidobacteria (Castro et al 2010).…”

“…PRISM then uses regression algorithms to estimate averages for the specific grid cell (PRISM Climate Group, Oregon State University, http://prism.oregonstate.edu). We chose to use a single month average rather than yearly averages as microbial communities can respond quickly to seasonal variation (Cregger et al 2012;Wasserstrom et al 2017).…”