Short rotation willow on the prairie potholes’ degraded marginal
riparian lands: a potential land-use practice to manage soil salinity
Abstract
Land-use practice shift in the wetland riparian zone can influence
groundwater table (GWT) fluctuations and salts dynamics, potentially
leading to soil salinization. The risk of soil salinization linked with
high water tables could better manage using high growing capacity and
deep-rooted phreatophytic vegetation via ‘biodrainage’ approach. We
evaluated the impacts of short rotation willow (SRW) plantation on soil
and groundwater salinity linked to shallow GWT fluctuations and compared
with adjacent annual crop (AC) and pasture (PA) in a field experiment.
Groundwater salinity (ECgw) along with depth to GWT and soil salinity
(ECsoil at 0-60 cm depth) were measured along transects within each
land-use practice in two prairie pothole region (PPR) wetland sites (A
and B). The variations in ECgw were significant (p < 0.05)
across land-uses; however, inconsistent between sites. The positive
correlation with ECgw, ECsoil, and total dissolved salts (TDS) indicated
higher salinity and salt accumulation with increased depth to GWT in
both sites. The ECsoil varied significantly (p < 0.05) among
land-use practices; however, no consistent land-use patterns were
observed between sites. Throughout the experimentation, site B
consistently exhibited higher ECsoil (two-fold) than site A. Decreasing
inclinations were observed in ECsoil with increasing SRW biomass at both
depths (i.e., 0-30 and 30-60 cm) and vice versa. This study refines our
knowledge of SRW linked potential hydrological alteration and its
implication on salinity, which provides critical context for degraded
marginal riparian wetland soil management in the PPR.