Analysis of Soil microbial carbon metabolic function, functional diversity and community similarity of six profiles from Luvisols

The study investigated the microbial carbon metabolic function, functional diversity, and community similarity of six profiles from Luvisols. The Community Level Physiological Profiling (CLPP) technique and the Biolog EcoPlate method based on it were used to determine microbial carbon metabolic function and functional diversity. Soil microbial carbon metabolic function (SMCMF) was found to differ among the six soils, despite all being Luvisols. The sample TA3, under mixed broadleaf vegetation and pH 7.4, showed the highest SMCMF, while the lowest values were observed in sample TA6 under mixed broadleaf and coniferous vegetation and pH 5.1. Carbohydrates were the preferred carbon source for the microbial communities in the studied Luvisols, while the amine/amide group was poorly utilized (only in TA5). The results for functional diversity ranged from 19.35% to 38.71%, with the highest functional diversity found in samples under broadleaf vegetation (TA2, TA3, and TA5). There was a positive correlation (r=0.74) between soil microbial functional diversity and soil organic carbon content, but no such correlation was observed with soil pH. The Simple Matching Coefficient was calculated for the studied soils. TA1 and TA6, with the highest % functional diversity, showed the most similarity finger print (SMC=77%). TA3 and TA5, with the lowest % functional diversity, showed the least similarity (35%). The results of this study confirm the need for further analysis of soil microbial communities, and the importance of considering soil microbial carbon metabolic function, functional diversity and community similarity as separate parameters of the soil microbial community in forest ecosystems.