Microbiota shift during leaf decomposition in different simulated mangrove sediments

The decomposition of mangrove litter is important for environment nutrient cycling. The dynamic changes of mangrove plant polyphenols during the process of leaf decomposition and their association with sediments and microbial diversity were studied in simulated indoor tidal systems. Soluble polyphenols could be released at the early stage of leaf decomposition, leading to higher content of tannin and decreasing content of ammonia nitrogen. Soil characteristics fluctuated significantly at the early stage of leaf decomposition, while it became stable as the process goes on. Microorganisms were of higher capacity to metabolize carbon in the early stage of leaf decomposition than the latter one. And microorganisms in Avicennia marina and Sonneratia apetala sediments were able to metabolize carbon with significantly higher capacity than that in Kandelia obovata, all of which were higher than the blank control one. Microorganisms in S. apetala sediment could use more varieties of sugars as carbon sources. Microbial diversities in all the sediments increased at the early stage of leaf decomposition, corresponding to the development of carbon metabolism capacities. Studies here provide important information of correlationships between carbon utilization and microbial diversity during leaf decomposition in different simulated mangrove sediments. Results will be useful for further research on nutrient cycling in mangrove forests.