Short-Term Snow Removal Alters Fungal but Not Bacterial Beta Diversity and Structure during the Spring Snowmelt Period in a Meadow Steppe of China.

Hengkang Xu,Nan Liu,Yingjun Zhang

doi:10.3390/jof8030234

Abstract

Global climate change is altering the amounts of ice and snow in winter, and this could be a major driver of soil microbial processes. However, it is not known how bacterial and fungal communities will respond to changes in the snow cover. We conducted a snow manipulation experiment to study the effects of snow removal on the diversity and composition of soil bacterial and fungal communities. A snow manipulation experiment was carried out on the meadow steppe in Hulunbuir, Inner Mongolia, China, during the winter period October 2019–March 2020. Soil samples were collected from the topsoil (0–10 cm) in mid-March 2020 (spring snowmelt period). Snow removal significantly reduced soil moisture and soil ammonium concentration. Lower snow cover also significantly changed the fungal community structure and beta diversity. Snow removal did not affect the bacterial community, indicating that fungal communities are more sensitive to snow exclusion than bacterial communities. The relative importance analysis (using the Lindeman–Merenda–Gold method) showed that available nitrogen (AN), soil water content (SWC), total organic carbon (TOC), microbial biomass carbon (MBC), and microbial biomass nitrogen (MBN) together explained 94.59% of the variation in soil fungal beta diversity, where AN was identified as the most important predictor. These finding provide insights into potential impacts of climate warming and associated reduced snow cover on soil microbial communities and processes.

Highlights

Climate change is predicted to reduce the thickness of the snow cover in many coldclimate regions in the world [1,2]
Reduced snow cover associated with winter climate change can produce drastic changes in soil temperature and moisture during the spring snowmelt, which may in turn influence soil biological processes, especially those related to soil bacterial and fungal communities [8–10]
Octoberthan to 1 May), the minimal snow removal (Table 1),soil indicating an insulating effect under of snow cover under theunder snow the and averaged temperatures were higher the control than removal. This may(Table be due1),toindicating snow cover a pooreffect conductor of cover heat, with low the snow removal anbeing insulating of snow under thethermal snow conductivity and abehigh capacity, and it influences soil temperature changremoval

Summary

Introduction

Climate change is predicted to reduce the thickness of the snow cover in many coldclimate regions in the world [1,2]. Reduced snow increases soil freezing depth, increases soil temperature variability, and reduces soil moisture [3,4]. Soil microclimatic conditions (e.g., temperature, moisture, frost intensity, and duration) regulate soil microbial communities in cold climate ecosystems [3,5–7]. Changes in soil microclimatic conditions will likely have severe ecological impacts due to the importance of winter snow for meadow ecosystem functioning. Water availability is a prior limiting factor for primary production, and snowfall in winter is an important source of water in the meadow steppe in Inner Mongolia. Reduced snow cover associated with winter climate change can produce drastic changes in soil temperature and moisture during the spring snowmelt, which may in turn influence soil biological processes, especially those related to soil bacterial and fungal communities [8–10]

Methods

Results

Discussion

Conclusion