Profiling the Bacterial Diversity in a Typical Karst Tiankeng of China

Abstract

While karst tiankengs have a higher capacity to act as safe havens for biodiversity in changing climates, little is known about their soil microorganisms. To fill this gap, we investigate the distribution and driving factors of the bacterial community in karst tiankeng systems. There is a significant difference in the soil characteristics between the inside and the outside of a karst tiankeng. At the karst tiankeng considered in this study, the bacterial composition, in terms of the operational taxonomic unit (OTU), was found to be significantly different in different soil samples, taken from diverse sampling sites within the collapsed doline or the external area, and showed a high habitat heterogeneity. The dominant phylum abundances vary with the sampling sites and have their own indicator taxa from phylum to genus. Unlike the primary controlling factors of plant diversity, the microclimate (soil moisture and temperature), soil pH, and slope dominated the distribution of the bacterial community in karst tiankeng systems. Our results firstly showed the distribution characteristics of bacterial communities and then revealed the importance of microhabitats in predicting the microbial distribution in karst tiankeng systems.

Slope Aspect Affects The Soil Microbial Communities In Karst Tiankeng Negative Landforms

“…The composition of the microbial community is similar on different slopes, but exhibits differences in microbial abundance. At the phylum level, Proteobacteria had the highest abundance in all soil samples, which were consistent with previous studies [4,12]. In addition, Actinobacteria, Chloro exi, Acidobacteria, Verrucomicrobia and Firmicutes were also abundant in all soil samples.…”

“…The signi cant difference between the shady and sunny of SOM content may have affected the microbial communities. pH has been widely regarded as an important soil properties affecting microbial communities in karst areas [4,38]. Therefore, the difference in plant community composition and soil nutrients between shaded and sunny slopes is the main driving factor for the formation and evolution of microbial communities.…”

“…The karst tiankeng is a special and grand negative surface terrain rst discovered in the karst area of southern China at the end of the 20th century [1]. Affected by the steep rock wall and its own depth, a local microclimate different from the surface of the tiankeng has been formed inside the tiankeng, which has nurtured unique resources of animals, plants and microorganisms [2][3][4][5]. As we all know, human activities have caused environmental problems such as rocky deserti cation, loss of land resources, and ecosystem degradation in karst areas, turning them into vulnerable and sensitive areas of the ecological environment [6][7].…”

“…However, there are few studies on the distribution of microbial resources and their mechanism of action in the karst tiankeng ecosystem. Pu et al [4] and Jiang et al [12] results showed that the distribution of microbial communities in the karst tiankeng ecosystem has obvious heterogeneity. As the most diverse and species-rich taxa on earth, soil microorganisms promote the energy ow and material transformation of the ecosystem and maintain the normal operation of the ecosystem [13,14].…”

The Biomolecular Spectrum Drives Microbial Biology and Functions in Agri-Food-Environments

“…Bacterial diversity in the soil of changing climate of Karst Tiankeng of China was studied by Pu et al [28]. The authors reported the distribution characteristics of bacterial communities in the eco-niche that showed high habitat heterogeneity.…”