Can isolated and riparian wetlands mitigate the impact of climate change on watershed hydrology? A case study approach

Abstract

The effects of wetlands on stream flows are well established, namely mitigating flow regimes through water storage and slow water release. However, their effectiveness in reducing flood peaks and sustaining low flows is mainly driven by climate conditions and wetland type with respect to their connectivity to the hydrographic network (i.e. isolated or riparian wetlands). While some studies have demonstrated these hydrological functions/services, few of them have focused on the benefits to the hydrological regimes and their evolution under climate change (CC) and, thus, some gaps persist. The objective of this study was to further advance our knowledge with that respect. The PHYSITEL/HYDROTEL modelling platform was used to assess current and future states of watershed hydrology of the Becancour and Yamaska watersheds, Quebec, Canada. Simulation results showed that CC will induce similar changes on mean seasonal flows, namely larger and earlier spring flows leading to decreases in summer and fall flows. These expected changes will have different effects on 20-year and 100-year peak flows with respect to the considered watershed. Nevertheless, conservation of current wetland states should: (i) for the Becancour watershed, mitigate the potential increase in 2-year, 20-year and 100-year peak flows; and (ii) for the Yamaska watershed, accentuate the potential decrease in the aforementioned indicators. However, any loss of existing wetlands would be detrimental for 7-day 2-year and 10-year as well as 30-day 5-year low flows.

Connectivity of Streams and Wetlands to Downstream Waters: An Integrated Systems Framework

“…; Evenson et al. ; Fossey and Rousseau ). Furthermore, groundwater (Harbaugh ; Neff and Rosenberry ) and coupled surface‐water–groundwater models (Ameli and Creed ) are beginning to be adapted and applied to answer questions about wetland connectivity.…”

Nonlinear Response of Streamflow to Climate Change in High-Latitude Regions: A Case Study in Headwaters of Nenjiang River Basin in China’s Far Northeast

“…For example, the catchment of Shihuiyao Gauge Station (G1 in Figure 1) are primarily covered by forests and wetlands. Wetlands and forests provide important hydrological services including storage and slow release of water, flood mitigation and low flow support, which can alter the response of streamflow regimes to climate change [44][45][46].…”

Modeling Connectivity of Non‐floodplain Wetlands: Insights, Approaches, and Recommendations

“…); the wetland complex scale (e.g., on the order of tens to hundreds of hectares in size; Leibowitz and Vining ; Hayashi et al. ); and large‐watershed scale (e.g., on the order of hundreds of hectares to thousands of square kilometers; Fossey and Rousseau ; Golden et al. ).…”

“…), distributed water‐level sensor networks (e.g., McLaughlin and Cohen ; Epting et al. ), a suite of environmental tracer data (e.g., Fossey and Rousseau ; Thorslund et al. ), and nutrient isotope data (Kendall et al.…”