Advanced monitoring of soil-vegetation co-dynamics reveals the successive controls of snowmelt on soil moisture and on plant seasonal dynamics in a mountainous watershed

Frontiers in Earth Science

Earth Science

Baptiste Dafflon¹  John Peterson¹  Nicola Falco¹  Haruko M. Wainwright²  Emmanuel Léger³  Susan S. Hubbard⁴  Kenneth H. Williams⁵  Jiancong Chen⁶ 

[1] Climate & Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States;Climate & Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States;Department of Nuclear Science and Engineering and Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States;Climate & Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States;Geosciences Department, Université Paris-Saclay, Gif-sur-Yvette, France;Climate & Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States;Oak Ridge National Laboratory, Oak Ridge, TN, United States;Climate & Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States;Rocky Mountain Biological Lab, Gothic, CO, United States;Department of Civil and Environmental Engineering, University of California, Berkeley, CA, United States;

关键词: hillslope;    snow impact;    soil moisture;    vegetation growth;    seasonal dynamic;   

DOI  :  10.3389/feart.2023.976227

 received in 2022-06-23, accepted in 2023-04-03,  发布年份 2023

来源: Frontiers

【 摘 要 】

Evaluating the interactions between above- and below-ground processes is important to understand and quantify how ecosystems respond differently to atmospheric forcings and/or perturbations and how this depends on their intrinsic characteristics and heterogeneity. Improving such understanding is particularly needed in snow-impacted mountainous systems where the complexity in water and carbon storage and release arises from strong heterogeneity in meteorological forcing and terrain, vegetation and soil characteristics. This study investigates spatial and temporal interactions between terrain, soil moisture, and plant seasonal dynamics at the intra- and inter-annual scale along a 160 m long mountainous, non-forested hillslope-to-floodplain system in the upper East River Watershed in the upper Colorado River Basin. To this end, repeated UAV-based multi-spectral aerial imaging, ground-based soil electrical resistivity imaging, and soil moisture sensors were used to quantify the interactions between above and below-ground compartments. Results reveal significant soil-plant co-dynamics. The spatial variation and dynamics of soil water content and electrical conductivity, driven by topographic and soil intrinsic characteristics, correspond to distinct plant types, with highest plant productivity in convergent areas. Plant productivity in heavy snow years benefited from more water infiltration as well as a shallow groundwater table depth. In comparison, low snowpack years with an early first bare-ground date, which are linked to an early increase in plant greenness, imply a short period of saturated conditions that leads to lower average and maximum greenness values during the growing season. Overall, these results emphasize the strong impact of snowpack dynamics, and terrain and subsurface characteristics on the heterogeneity in plant type and seasonal dynamics.

【 授权许可】

Unknown   
Copyright © 2023 Dafflon, Léger, Falco, Wainwright, Peterson, Chen, Williams and Hubbard.