Assessing potential ecological impacts of land use and climate change to inform watershed planning

Session: Connecting Management Needs and Science Information (1)

Lyndsay Cartwright, Toronto and Region Conservation Authority, [email protected]
Namrata Shrestha, Toronto and Region Conservation, [email protected]

Abstract

Watershed planning continues to be an important tool for identifying and protecting natural systems and their associated ecosystem functions. This analysis examined the impact of three future land use scenarios on the terrestrial ecosystem within the Carruthers Creek watershed in Ontario to inform the watershed planning process. Existing conditions were compared to three future land use scenarios representing changes based on approved urban development (+OP), enhancement of the natural heritage system (+NHS), and potential additional urbanization in the headwaters (+Potential Urban). To assess impacts on habitat quantity, quality, connectivity, and climate vulnerability under each land use scenario, this analysis was informed by a combination of data including orthophotos, existing watershed plans, municipal Official Plans, field data, ecological modelling derived data and current best management practices. Overall, the results suggest that the additional natural cover under the +NHS scenario should provide ecological benefits above and beyond the existing land cover, but its ecological function may be compromised as build out progresses under the +Potential Urban scenario. Recommendations are provided for habitat conservation and species protection to minimize land use and climate change impacts on the terrestrial ecosystem to facilitate achieving natural heritage objectives, effective land use planning and climate resilience.