Studies have indicated that early- and mid-successional plants generally suffered from negative to neutral plant鈥搒oil feedback. However, the role of such plant鈥搒oil feedback during the postglacial primary succession of plants and microorganisms has not been fully understood.

In a study published in Science of The Total Environment, researchers from the Xishuangbanna Tropical Botanical Garden and the Chengdu Institute of Biology of the Chinese Academy of Sciences sought to uncover the drivers of ecosystem succession during glacial retreat based on plant competition, microbial community structure and plant鈥搒oil鈥搈icrobial interactions. They tested whether plant鈥搒oil鈥搈icrobial interactions explain plant primary succession in the Gongga Mountain glacial retreat chronosequence.

To determine how plant鈥搒oil鈥搈icrobial interactions mediate the vegetation dynamics, the researchers treated soils from three stages of primary succession in the Mount Gongga glacial retreat with sterilized soil and living soil as controls, and then planted with combinations of intra- and inter-species competition.

The researchers then used plant biomass to assess inter-plant competitiveness and the effects of habitat legacies. They then measured soil microbial community composition (bacteria and fungi) and mycorrhizal colonization rates to estimate the patterns and drivers of plant鈥搒oil鈥搈icrobial interactions on aboveground plant succession.

They found that plant鈥�soil鈥搈icrobial interactions were coincident with the occurrence of pioneer plants during primary succession in glacial retreat areas. The habitat legacy effect shifted from negative in the early stages to positive in the middle and late stages due to increasing nutrient availability and the presence of specific microbial groups.

In addition, ectomycorrhizal fungal specialists were most important for the plant鈥搈icrobial interactions during the late successional stages. Turnover of pathogenic fungi determined habitat legacy effect, especially in the early stages.

"Our results provide a better ecological understanding and allow prediction of vegetation succession on young soils and the development of new ecosystems," said Li Weitao of XTBG.