Seasonal Patterns of Microbial Community Structure and Enzyme Activities in Coastal Saline Soils of Perennial Halophytes

Abstract Perennial halophytes are known to be one of the most influential parameters in coastal ecosystem affecting ecosystem processes. The aim of this study was to investigate the changes in soil microbial community structure and enzyme activities in different halophyte‐covered soils ( Arthrocnemum indicum , Aeluropus lagopoides , Heleochloa setulosa and Suaeda nudiflora ) with control soil (un‐vegetated) that were collected in three seasons (rainy, winter and summer) from intertidal coastal soils of Gujarat, India. Soil microbial community structure was assessed using phospholipid fatty acid (PLFA) profiling. Halophytes influenced significantly soil micro‐environment by exerting effects on the soil chemical characteristics, enzyme activities and microbial community structure. The activities of β‐glucosidase, urease and alkaline phosphatase were significantly higher in halophyte‐covered soils than in control soil. Among four halophyte‐covered soils, the highest amounts of total, bacterial, actinomycetes and fungal PLFAs were observed in Arthrocnemum soil. The concentrations of total, bacterial, actinomycetes and fungal PLFAs were also significantly higher in summer and winter seasons than in rainy season, whereas enzyme activities also vary with seasons. The non‐metric multidimensional scaling analysis PLFA profiling revealed that the structure of microbial community significantly differed in all seasons as well as between control and halophyte‐covered soils. These shifts in microbial community were due to the higher abundance of Gram‐positive, total bacterial and actinomycetes PLFAs in summer and winter seasons than in rainy season, whereas abundance of fungal biomarker was significantly higher in rainy season than in other seasons. Among halophytes, significantly higher abundance of Gram‐positive, Gram‐negative and total bacteria was observed in Arthrocnemum , Heleochloa and Suaeda whereas the lowest in control soil. Halophytes exhibited improved soil microbial activities, which is important for healthy ecosystem. Copyright © 2017 John Wiley & Sons, Ltd.