Analysis of spatiotemporal variations in the characteristics of soil microbial communities in Castanopsis fargesii forests

Abstract

Castanopsis fargesii is a good afforestation plants and various microorganisms play important roles in mediating the growth and ecological functions of this species. In this study, we evaluated changes in microbial communities in soil samples from C. fargesii forests. The phospholipid fatty acid (PLFA) biomarker method was used to obtain bacteria, fungi, actinomycetes, gram-positive bacteria (G?), gram-negative bacteria (G-), aerobic bacteria, and anaerobic bacteria to investigate spatiotemporal changes in microbial communities during the growing season. The results show that soil microorganisms were mainly concentrated in the upper 20-cm layer, demonstrating an obvious surface aggregation (P \ 0.05). Large amounts of litter and heavy rainfall during the early growing season resulted in the highest PLFA contents for various microorganisms, whereas relatively low and stable levels were observed during other times. The dominant species during each period were bacteria. G? or aerobic bacteria were the main bacterial populations, providing insights into the overall trends of soil bacterial PLFA contents. Due to the relative accumulation of refractory substances during the later stages of litter decomposition, the effects of fungi increased significantly. Overall, our findings demonstrate that the main factors influencing microbial communities were litter, rainfall, and soil field capacity.

Effects of Forest Gap on Soil Microbial Communities in an Evergreen Broad-Leaved Secondary Forest

“…The ratios of fungal/bacterial (18:2ω6 for fungi) and Grampositive(G + )/Gram-negative (G − ) bacterial markers were also obtained. The absolute amount of PLFA was calculated by the area normalization method using the following formula ( [47,48]…”

Regulation of soil organic carbon dynamics by microbial communities during reforestation of Chinese fir plantations after clear‐cutting

“…The relative abundance of Gram‐positive or Gram‐negative bacteria (G+:G‐) may also shift with the succession age, and the increased G+:G‐ ratio would reflect fast consumption of nutrients (Moore‐Kucera & Dick, 2008) and the development of stress alleviation strategies of the communities after clear‐cut. The increase in the fungal/bacterial (F:B) ratio could reflect the enhancement of soil system stability (Qiao et al, 2020). For the clear‐cuttings of Douglas‐fir ( Pseudotsuga menziesii ) of various ages (8 and 25 years), developed under cold and moist climates, reduction of total phospholipid fatty acids (PLFA), bacteria, and fungi were found; however, 25 years of recovery after clear‐cutting was sufficient for microbial communities to recover to a state similar to old‐growth forests (Moore‐Kucera & Dick, 2008).…”