LUMASS - Waitaki Catchment

This case study seeks to address the growing interest in and awareness of the role that ecosystem services play in human lives and our strong dependence on these services for our wellbeing and health.

This study uses the New Zealand example of the Waitaki Catchment, an area with a strong economic dependency on agriculture, to provide and explore an example of the possibility of optimising land use to both enhance and develop ecosystem services whilst also maintaining economic returns. 

LUMASS has been used in this study because of the need to be able to quantify ecosystem services as a function of land use, therefore, making them comparable to other economic land uses in a given study area. This case study aimed to hold current economic outputs as a constant whilst enhancing and developing ecosystem services in the area.

The Land-Use Management Support System (LUMASS) is a free and open-source software tailored to land-use modelling and optimisation. It is built on open source software libraries for geospatial raster-based processing, visualisation, and optimisation. Modelling inputs for this study included land use, land cover as well as ecosystem services which only included clean water provision, natural habitat provision, provision of food and water flow regulation. LUMAAS does this within a set of practical land use restrictions as defined by the user.

For this study economic production from existing sheep, beef and dairy was held as a constant whilst within the Waitaki catchment boundaries the model made efforts to adjust land use spatially making improvements to water quality and natural habitat under the practical constrains of where each land use could occur. 

Three scenarios were run in the Waitaki catchment area as follows;

 

Scenario 1

   Scenario 2

Scenario 3

Land Use Options

Dairy, Sheep & Beef, Conservation Land

Objective

Maximise Clean Water Provision

   Maximise Habitat Provision

Maximise Water regulation

Criteria constraint

Maintain Gross outcome for dairy and for sheep & beef

Spatial Constraint

Dairy and Sheep & Beef in suitable areas

 

The resulting land use configurations were as follows;

LUMASS outputs photo

These scenarios highlighted that a significant reconfiguration of land use within the catchment area could have notable effects on the improvement of water quality and habitat provision with variable results on water yield, all with constant economic outputs.

It is noted in this case study that the outputs of this model showing optimal land use configurations act as a useful communication tool. It is however highlighted that results should be interpreted with caution; it is difficult to quantify ecosystem services accurately especially when the value that cultural ecosystem services hold is considered. This coupled with other limitations in modelling, such as the variable interaction of hydrologic systems with ground water and irrigation system, means that as with all models an open mind should be taken with the results.

Associated Models

Land Use Management Support System (LUMASS)

The Land Use Management Support System (LUMASS) was developed by Alexander Herzig of Landcare Research it is a free and open source software.

References

Ausseil, Anne-Gaelle; Herzig, Alexander; and Dymond, John (2012): "Optimising Land Use for Multiple Ecosystem Services Objectives: A Case Study in the Waitaki Catchment, New Zealand". 9th International Congress on Environmental Modelling and Software. 249.