Spatial indices and indicators to facilitate catchment planning with multiple objectives

Catchment areas are natural delineations to plan for multiple land- and water-related objectives, such as improvement of water quality, mitigation of climate change, and halting biodiversity loss. However, there is a lack of practical tools that facilitate management, conservation, and restoration of land and water ecosystems in the catchment areas. To address this need, we have developed a novel geospatial index-based approach to show how to prioritize sub-catchments that need to be targeted in catchment planning. Furthermore, we have piloted and validated the approach in two catchments in Finland. The approach is composed of (1) calculation of four indices that utilize existing geospatial data related to water quality management, climate change mitigation, climate change adaptation, and biodiversity conservation, and (2) validation of the indices and more detailed indicator maps in landowner interviews and a stakeholder workshop. The results show that different sub-catchments have been ranked among the top for each of the four indices. This suggests a need for balancing between different environmental targets if a limited number of sub-catchments is selected for more detailed assessments of management measures. In the validation step, the approach is widely regarded as important and timely, which highlights the need for methods that allow spatial prioritization and allocation of potential environmental measures. Prioritization is needed because resources are often insufficient, and for the sake of cost-effectiveness, it is important that the selection of sites is based on objective criteria rather than solely on landowners' initiative. • Spatial allocation of environmental measures should be prioritized in catchments. • We prioritized sub-catchments based on water, climate, and biodiversity objectives. • Indices yielded varying sub-catchment priorities. • We validated the approach through a stakeholder workshop and landowner interviews. • Stakeholders and landowners emphasized the need for practical planning tools.