Reed decomposition under Bacillus subtilis addition conditions and the influence on water quality

Abstract

In order to explore the effects of bacteria on the decomposition processes and water environmental conditions, we used litter bag method and compare reed litter decomposition rates under different Bacillus subtilis addition treatments. Neither mesh size nor bacterial treatment have significant effects on the decomposition rates in the earlier phase. But in last three retrieves, the decomposition rates of litter bags with Bacillus subtilis addition were significantly (p = 0.012) higher than that without Bacillus subtilis addition treatment. As for bacterial influence water parameters, aquatic environmental markers ammonia-nitrogen (NH3-N), total phosphorus (TP), dissolved oxygen (DO), and chemical oxygen demand (COD) didn't show significant difference between different Bacillus subtilis addition treatments. The decomposition rates were affected by litter quality and water parameters. Furthermore, the N/P and C/P ratios of litter were good predictors for litter decomposition. Our findings suggested that the bacterial inoculation could be an excellent approach to facilitate the decomposition processes and nutrient cycles in the wetland ecosystems, but it might require more than 45 days to see the positive effects.