InVESTing in Aquatic Ecosystem Services: Improving conservation decision-making with the incorporation of a seasonal cryosphere in the modelling of water quantity

LAVENDER, T.M.; SCORDO, F.; PERILLO, V.L.; SEITZ, C.; BRENDEL, A.S.; RUSAK, J.A.; ARNOTT, S.E.; WEMPLE, B.C.; PERILLO, G.M.E.; PICCOLO, M.C.; CAICEDO, M.I.V.

Montreal

Conferencia; Canadian Conference For Fisheries Research; 2017

Society of Canadian Limnologists

Aquatic ecosystems are being placed under increasing pressure and stress due to changes in land use, land cover, and climate change. These factors can increase stress by altering flow regimes and linked factors such as nutrient and sediment loading, and water temperature. One of the key ways that we can manage these systems, and the ecosystem services they provide, is to prioritise parcels of land for conservation based on the service they perform. One such method is to select parcels of land for conservation based on their relative contributions to base flow (ground water regeneration) and quick flow (surface run off). Thus, tools that are able to model the partitioning of flow across a landscape are in demand. The Natural Capital Project's InVEST Seasonal Water Yield model has been developed to provide an ecosystem services approach to making conservation decisions based on flow partitioning; however, periods of freezing temperatures and snow accumulation are not accommodated by the model. As a result, spring runoff (quick flow) and groundwater recharge (base flow) are inadequately modeled. By incorporating snow accumulation and spring thaw conditions into the model predictions of seasonal contributions to base and quick flow will be improved. We modified the InVEST Seasonal Water Yield model to incorporate freezing temperatures, snow accumulation and spring freshet. We then compared the results to those from the unmodified model across three diverse watersheds to demonstrate the relevance of the models across ecosystems as well as their utility for assessing changes in aquatic ecosystem services.