Evaluating the impact of land-use practices on soil organic carbon (SOC) in the Canadian prairie pothole region (PPR) is of concern due to the potential to sequester carbon and sustaining soil health. In a eld experiment, SOC content, carbon fractions, and chemical composition were assessed under short rotation willow (SRW) plantation in the marginal riparian zones of two PPR wetland sites and compared with adjacent annual crop (AC) and pasture (PA). The SOC, water extractable (WEOC), light fraction (LFOC), and particulate organic carbon (POC) were used to evaluate the content and its fractions, whereas Fourier Transform Infrared (FTIR) spectroscopy was used to characterize the chemical composition. The SOC was higher in PA in both sites; however, signi cant (p < 0.05) only in site B. The SOC, LFOC, and POC followed a similar land-use pattern in both sites, i.e., PA > SRW = AC. The SOC and WEOC were signi cantly higher (p < 0.05) in 0-15 cm across all land-use practices. The ratios of phenolic and amides to polysaccharides were signi cantly higher (p < 0.05) in site A, while aromatic and carboxylic to polysaccharides were lower under SRW in both sites indicated microbial synthesis of these substances. The abundance of SOC functional groups was higher in the subsoil, accompanied by altered spectral properties with depths showing the potential soil organic matter transformation related to carbon fractions changes. The higher alkyl-C to O-alkyl-C ratio at 15-30 cm under SRW suggested a higher degree of decomposition and better SOC stability.

Land-use change and climatic variability are signi cant drivers for the loss of ecosystem services and soil quality in the prairie pothole region (PPR) wetland systems. Land-use induced changes in groundwater table and salinity may in uence biogeochemical processes facilitated by extracellular enzymes (EEs) involved in soil organic matter (SOM) decomposition. The effects of changing groundwater table and salinity on β-glucosidase (BG), N-acetyl glucosaminidase (NAG), and alkaline phosphatase (AP) activities were assessed in wetland soils collected from three different adjacent riparian land-use practices in the PPR. In a microcosm study conducted over ten weeks, soils were treated with groundwater salinity (control, 6 mS cm − 1 , and 12 mS cm − 1 ) and declining groundwater table depths. Extracellular enzyme activities (EEAs) differed signi cantly (p < 0.05) among soils from different land-uses and between

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 be better managed by using high growing capacity and deep‐rooted phreatophytic vegetation via the 'biodrainage' approach. We evaluated the impacts of short rotation willow (SRW; Salix dasyclados Wimm.) 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 in both 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, land‐use patterns were not consistent in both sites. Throughout the experimentation, site B consistently exhibited higher ECsoil (two‐fold) than site A. We observed a decreasing inclination 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 plantation‐linked potential hydrological alteration and its implication on salinity, which provides a critical context for degraded marginal riparian wetland soil management in the PPR.

Land-use practices can alter shallow groundwater and salinity, further impacting greenhouse gas (GHG) emissions, particularly in the hydrologically dynamic riparian zones of wetlands. Emissions of CO2, CH4, and N2O were estimated in soil cores collected from two prairie pothole region (PPR) sites with three adjacent land-use practices (i.e., annual crop = AC, pasture = PA, and short rotation willow = SRW) and treated with declining water table depths (2 to 26 cm), and salinity (S0 = control, S1 = 6 mS cm− 1, and S2 = 12 mS cm− 1) in a microcosm experiment. Land-use practices significantly (p < 0.001) affected GHG emissions in soils from both sites in the order of PA > AC = SRW. Compared to the control, emissions of CO2 and CH4 were significantly lower under higher salinity treatments (i.e., S1 and S2), while N2O was significantly higher (p < 0.05). Emissions under declining groundwater table depths were significantly (p < 0.001) variable and specific to each gas, indicating the impacts of shifted soil moisture regime. Overall, the CO2 and CH4 emissions increased up to week four and then decreased with declining water table depths, whereas N2O emission increased up to a maximum at week six. The soils from SRW had considerably lower global warming potential compared to AC and PA. Groundwater salinity in soils from contrasting land-use in the PPR has significant impacts on GHG emissions with potential for crucial climate feedback; however, the magnitude and direction of the impacts depend on hydrology.

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.