Scientists Find Soil Microbial Functional Gene Beta-diversity Is Determined By the Variation in Aboveground Plant Biomass Composition

Release Time:2018-02-06 Big Small

Understanding linkages between the diversity of organisms aboveground and that of organisms belowground constitutes an important challenge for our knowledge of the maintenance and stability of ecosystem processes. Increased attention has been paid to the biodiversity linkages between aboveground and belowground biological communities in last decade.

However, since most studies did not survey the corresponding plant and microbial communities within strictly dependent sampling sites, direct comparisons of plant-microbial diversity at the community level are still limited.

Dr. LI Hui and her colleagues from the research group of Soil Chemistry in Institute of Applied Ecology, CAS took advantage of a 9-year field experiment established in a typical steppe in Inner Mongolia, China, and explored diversity linkages between plant and soil microbial communities.

They evaluated soil microbial community composition by both taxonomic (16S rRNA) and functional genes, and estimated plant community composition by traditional “species composition” and species-specific “biomass composition”, which constitutes the biomass of each species.

They found that the richness and Shannon diversity of 16S rRNA genes, was significantly correlated with plant species richness and Shannon diversity, whereas microbial functional gene richness was weakly associated with total plant biomass. Microbial beta-diversity, evaluated by 16S rRNA genes, was coupled with plant beta-diversity as estimated by both “species composition” and “biomass composition”, while microbial functional gene beta-diversity was only correlated with the dissimilarities of “biomass composition”.

The observed data suggested that soil metabolic potentials could be more determined by the heterogeneity of resources returned to soil than controlled by the species composition of the macro-organism communities.

The functional gene detection by using Geochip is collaborated with Professor ZHOU Jizhong in Department of Microbiology and Plant Biology, University of Oklahoma, USA.

This research has been published in Plant and Soil as an article entitled “Soil microbial beta-diversity is linked with compositional variation in aboveground plant biomass in a semi-arid grassland”. This work was funded by National Key Research and Development Program of China,  and the National Science Foundation of China.

Fig. 1 Comparison of beta-diversity between plant and microbial communities. Bray-Curtis distances of microbial communities computed based on 16S rRNA gene data (a, b) and functional gene data (c, d) were regressed against plant community dissimilarity calculated based on the number of individuals in each species (a, c) and species-specific biomass (b, d), respectively (Image by LI Hui).