Effects of winter warming on the migration characteristics and pollution risk assessment of Zn, Cu, and Pb in the snow-soil continuum in seasonal snow cover area

The response of snow to climate warming is extremely sensitive. Climate warming will affect the melting rate of snow and its adsorption capacity for heavy metals, thereby affecting soil heavy metal content and pollution risk. This study regards snow and soil as a continuum, and two different warming treatments and one control treatment were set up with infrared radiometer to simulate the changing characteristics of this process under the background of future climate warming. In controlled experiments, the content of Zn, Cu and Pb in snow decreased significantly due to climate warming. Compared with the warming treatments, the concentrations of Zn, Cu, and Pb in the control treatment were increased by 6 mu g L-1, 4.9 mu g L-1, and 1 mu g L-1 and 8.3 mu g L-1, 1.75 mu g L-1, and 2.85 mu g L-1, respectively. The positive response of snow to climate warming directly affected the spatio-temporal distribution pattern of Zn, Cu, and Pb in soil, as a result, the Igeo of soil Zn increased by 0.221 and 0.165, the Igeo of soil Cu decreased by 0.076 and 0.080, and the Igeo of soil Pb decreased by 0.018 and 0.073, respectively. Thus, the living environment of soil microorganisms was changed, and the ecological environment of soil was significantly affected. Our results highlighted the importance of snow cover in assessing the risk of soil heavy metal pollution in the context of future warming, meanwhile, the results had important reference value for pollution prevention and sustainable development of farmland ecosystem in seasonal snow cover area.(c) 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).