Phylogenetic Diversity of Diazotrophs along an Experimental Nutrient Gradient in Mangrove Sediments
نویسندگان
چکیده
The diversity of diazotrophs was studied in the sediment of mangrove forests (Twin Cays, Belize) subjected to a long-term fertilization with nitrogen and phosphorus. Terminal Restriction Fragment Length Polymorphism (TRFLP) and cloning of PCR-amplified nifH genes were combined via in silico analysis to assign clones to TRFLP-nifH phylotypes, as well as to characterize the occurrence of phylotypes in response to environmental conditions. Results indicated that mangrove sediments from Belize harbor a unique diazotrophic community with a low metabolic diversity dominated by sulfate reducers. The variability of potential nitrogen-fixing sulfate reducers was explained by several environmental parameters, primarily by the abundance of dead roots in the sediments, and the concentration of H2S in the pore-waters. This study describes the complexity of microbial communities within the mangrove sediments with specific functional groups varying along environmental gradients. OPEN ACCESS J. Mar. Sci. Eng. 2015, 3 700
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