Interoperable Modelling - spatial economic optimisation

In this report we describe the application of the spatial modelling and optimisation framework LUMASS as a spatial optimisation tool in the Interoperable Modelling Project. We demonstrate the potential use of the optimisation component for exploring ecological, economic, and policy objectives in the Aparima catchment. We considered the dominant land uses in the catchment (dairy, sheep and beef, forestry) and characterised their performance regarding N leaching, sediment loss, GHG emissions, milk-solids production, and wool production. We modelled hypothetical scenarios that explore the best possible outcome for the catchment with respect to those indicators without changing the land-use system. Our modelling results suggest very little headroom to improve the catchment's performance without environmental and/or economic impacts. Incentive payments for nitrate leaching and/or sediment reduction have potential to be effective options to reduce environmental pollutants. However, our modelling results also highlighted the need for detailed land-use and land-use management information as well as spatially discriminate land-use performance assessments. Report prepared by Manaaki Whenua - Landcare Research for NIWA, July 2020