Long-term Soil Moisture Data Among Three Forested Watersheds Reveal Increasing Soil Moisture

Mauricio Barro*, Brooke Eastman and William Peterjohn, Department of Biology, West Virginia University, Morgantown, WV, 26506p>

Field (Broad Category): Biology (Agricultural & Environmental Sciences) 

Student’s Major: Political Science 

Soil moisture in forest ecosystems is an important source of water for both plants and soil microbes that can be altered by changes in climate, land use, vegetation, and soil conditions. To examine how some of these factors may influence soil moisture, I used long-term measurements of soil water in forested watersheds that differed in stand age and degree of soil acidity. More specifically, I compared measurements between three adjacent watersheds in West Virginia: one that was last cut ca. 1905; one that was clearcut ca. 1970 and has been experimentally acidified since 1989; and one that was clearcut ca. 1970 but was not experimentally acidified. Analysis of twelve years of measurements (from 2007 – 2019) revealed that soil moisture was consistently higher in the more mature, untreated watershed compared to the younger watersheds. When averaged across all forest stands and years, soil moisture declined through the growing season and reached its lowest level in early autumn, but the degree of seasonal decline varied among years. We hypothesize that this year-to-year variability is related to differences in climate, such as precipitation and temperature. These long-term data provide a unique and valuable resource to better understand dynamics of soil moisture. Determining the driving factors that influence soil moisture can help to predict variability in seasonal and inter-annual forest growth. 

Funding: 

Program/mechanism supporting research/creative efforts: WVU 497-level course