Assessment of multiple ecosystem services in New Zealand at the catchment scale
The ecosystem services approach to resource management considers all services provided by ecosystems to all sections of the community. As such, it could be used to assess sustainability of human development and equity in resource use. To facilitate the approach, tools are required at the level of detail at which policy and management decisions are made. We have developed spatially explicit models of indicators of important ecosystem services in New Zealand: regulation of climate, control of soil erosion, regulation of water flow (quantity), provision of clean water (quality), provision of food and fibre, and provision of natural habitat. The models were developed using lookup tables from process-based models to allow rapid evaluation of land-use scenarios. We demonstrate the application of the models to assess ecosystem services in a simulation of hill-country afforestation in the Manawatu catchment, which has recently seen increasing soil erosion in the hills leading to sedimentation of waterways. Each ecosystem service was assessed by calculating the change in the indicator relative to two extremes. The ecosystem services with the largest relative changes were control of soil erosion, carbon sequestration, and provision of wood.
erosion land-use change climate regulation landscape modelling scenario analysis water quality