Microbial Community Structure and Activity under Various Pervious Pavements

Abstract

The research reported in this paper compares the soil characteristics in terms of their microbial structures and activities under several pervious pavements. Due to differences in texture, construction, and permeable characteristics among these pavements, diverse microbes flourish in the underlying soil. The writers hypothesized that the soil structure under the JW pavement, a high-load-bearing water-permeable pavement, allows colonization of abundant and diverse microbes, thus supporting active and versatile microbial metabolism. The writers collected two soil layers, (1) aggregate and (2) soil bases, under the JW and three other pervious pavements, (1) asphalt, (2) concrete brick, and (3) concrete-glass block, installed side-by-side on a university campus in Taiwan. The writers analyzed the granulometry, water content, soil pH, total organic carbon, total nitrogen content, enzymatic activities, community-level physiological profiles, and phylogenetic bacterial diversity, and performed a microbiological assay. Results revealed that the activation and versatility of microbial activities, and the abundance and diversity of bacterial communities, were mainly related to the total organic carbon content among the pavements. The microbial compositions and their activities under the JW pavement were both superior to those under the other pervious pavements, except for the abundances of fungi and actinobacteria. Bacterial communities under the JW pavement were more abundant and diverse. The soil under the JW pavement also reflected more-activated and more-versatile microbial metabolism in all substrates and for specific types of functional guilds. These results were due to the characteristics of a looser structure, higher moisture, and a higher total organic carbon content.