The Role of Locally Derived Effective Microorganisms in Reducing Ammonia Volatilization from Soil and Its Potential to Enhance Nitrogen Mineralization.

Nutrient cycling and carbon fluxes in terrestrial ecosystems are closely related to the turnover of organic matter. Increasing the availability and retention of nitrogen and carbon in soil fertilized with organic soil amendments such as swine effluent could provide a more reliable source of nutrients from organic amendments. A potential application of Local Effective Microorganisms (LEMs) is as an inoculant to animal waste to improve biodiversity, soil health and promote plant growth.  We speculated that adding LEM to swine effluent when effluent is applied to the soil could increase biodiversity and result in greater mineralization of inorganic nitrogen for plant growth. Effective microorganisms or EMs are a mixed culture of naturally occurring microorganisms, including species of photosynthetic bacteria (Rhodopseudomonas palustris and Rhodobacter sphaeroides), lactobacilli (Lactobacillus plantarum, L. casei, and Streptococcus lactis), yeasts (Saccharomyces spp.), and Actinomycetes (Streptomyces spp.). The objective of the study is to assess the role of LEMs in reducing ammonia volatilization, carbon dioxide respiration, and to assess the potential nitrogen mineralization from soil fertilized with swine effluent (SE) +  LEM, SE + False LEM, (FLEM), and SE only. Treatments were applied in the winter for two years (2014 and 2015), to 5 x 10 m annual ryegrass (Lolium multiflorum) scientific name) plots in a 3 x 4 randomized complete block design. Observations made throughout the two seasons and soil samples were taken to analyze for pH and potentially mineralizable N after treatment applications. There was a 33% and a 28% reduction in nitrogen loss as ammonia in the first and second year of the study, from SE + LEM treatment plots compared to SE treatment plots (P< 0.10). No statistical differences in CO₂ respiration were found in 2014 between treatments (P < 0.10).  However in 2015, there was significantly greater CO₂ respiration (8%) from the SE + LEM inoculated plots compared to SE only treatment (p< 0.05).