Fast bacterial succession associated with the decomposition of Quercus wutaishanica litter on the Loess Plateau.

Understanding plant litter decomposition in broad-leaved forests is important because it influences the geochemical cycles of nutrients and represents a vital link in the global carbon cycle. Bacteria play an important role in litter decomposition, especially late in the decomposition process, when they become abundant. In this paper, we investigate bacterial community composition and diversity during about 1 year of Quercus wutaishanica litter decomposition using a molecular approach, to fill the gaps in knowledge about bacterial communities during decomposition. The results showed that the phyla Proteobacteria (Alpha and Betaproteobacteria), Actinobacteria, Bacteroidetes, and Acidobacteria were the most dominant throughout the experiment. As decomposition progressed, a dynamic succession of community and diversity was observed for different decomposition periods. Decay stages and seasonal shifts occurred by successful replacement of copiotrophic bacterial groups such as Betaproteobacteria in the early stage. During the entire process of decomposition, litter decomposition selectively stimulated the relative abundance of Alphaproteobacteria (Sphingomonas, Rhizobium, and Methylobacterium) and Bacteroidetes, but reduced the abundance of Massilia (Betaproteobacteria), Acidobacteria, and Actinobacteria. Among the abiotic factors, litter N and P content was the main factor driving the succession of litter bacteria. These results indicate the changes in decomposition stages in terms of the bacterial groups and elucidate the microbial community underpinnings of nutrient cycling in forest ecosystems. [ABSTRACT FROM AUTHOR]