A new review by Chinese scientists reveals how changes in snow depth and melting time can have profound impacts on vegetation, soil and microorganisms.

Snow is a key factor in many land ecosystems, especially in regions where it accumulates seasonally. Snow can insulate the soil from extreme cold, provide water and nutrients, and influence the timing and duration of the plant growing season. However, global warming has altered the characteristics of snow in many places, leading to thinner, patchier snow cover and earlier snowmelt. These changes can affect the ecological processes and functions of land ecosystems.

A team of researchers from the Institute of Applied Ecology of the Chinese Academy of Sciences has conducted a comprehensive review of the existing studies on the effects of snow changes on land ecosystems. The review, published in the journal Acta Ecologica Sinica, summarizes the current knowledge and identifies the knowledge gaps and research priorities.

The review shows that snow changes have complex and uncertain impacts on different ecosystem components, depending on the climate and soil conditions, and methods of simulating snow changes. For example, under the scenario of future climate warming, thinner and earlier melting snow may advance plant phenology, extend the growing season, increase the productivity and litter quantity, reduce the proportion of grasses compared to other plant types (e.g., forbs), stimulate soil microbial activity in early spring, enhance litter decomposition rate, and accelerate soil carbon and nitrogen turnover. However, reduced snow and earlier snowmelt may also cause early spring low temperature and summer drought, which may reduce vegetation productivity, litter quantity and quality, microbial activity, decomposition rate, and slow down carbon and nitrogen cycling.

The review also identifies some research gaps and challenges in the development of snow ecology, such as strengthening studies on the ecological linkage between vegetation community, soil carbon and nitrogen processes, and soil food web, conducting soil microbial community composition and function studies using genomic techniques, and performing remote sensing related studies.