Looking to the future of land evaluation and farm systems analysis
FIGURE 1 Combining land capability with resource condition under a land use to quantify ecosystem services provision for multi-function land evaluation.
Future shape of land evaluation
Land evaluation is formally defined as ‘the assessment of land performance when used for a specified purpose’ and has a long history of describing and quantifying the differences between units of land. The procedure uses limiting factors arising from climate, hydrology, landforms, soils and vegetation as the basis for evaluation of sustainable yields, with critical values determining the boundaries of suitability. In New Zealand, land use capability classification is the basis for assessing suitability for sustained production.
Two new trends emerging from land evaluation frameworks globally are the recognition of the wider functions provided by landscapes and the need for greater stakeholder participation in exploring the balance between economic, environmental, social, and cultural outcomes. With increasing demands on the finite land resource, land evaluation must go beyond assessment of land suitability for primary production alone and consider the performance of all services provided by a combination of land type, climate, land use, and management practices, as well as impacts on receiving environments.
A rapidly emerging multi-disciplinary approach to assess the multi-functionality of natural resources is the ecosystems approach based on the concepts of natural capital and ecosystem services. Natural capital is defined as the ‘stocks of natural assets that yield a flow of ecosystem goods or services into the future’. This concept comes from trying to frame the contribution of natural resources to the economy alongside built capital (factories, buildings), human capital (labour, skills), and social capital (education, culture). Ecosystem services are defined as ‘the benefits people obtain from ecosystems’ – not only food, but also flood mitigation, nutrients filtration, greenhouse gas regulation or pest regulation.
Adding an ecosystems approach to land evaluation enables the supply of ecosystem services to be directly linked to the performance of a combination of land type, land use and management intensity to deliver specific outcomes.
Emerging farm systems analytical capability
Farms are often an assemblage of multiple landscapes with a mixture of topographies and soil types, both of which influence pasture and crop production, as well as other ecosystem services. Importantly, these land units show different responses to inputs and practices. Today’s intensive agricultural systems are the product of successfully combining built capital with diverse natural resources (e.g. land, water) to produce food and fibre for profit. Future analysis of the farm system will need to be extended to include the implication of decision-making not just on food and fibre production, but also on the services our farm systems provide. This ecosystems approach creates the ability to define ‘ecological boundaries’ within which resources should be managed, addressing the purpose of the Resource Management Act 1991 (Section 5).
In our research programme, we are developing a new farm systems model “INFORM” (Integrated Farm Optimisation and Resource Allocation Model) that integrates biological data from each land management unit (similar natural resources and management practices) (LMU) within the farm. It uses LMU information to identify the mix of production enterprises and management regimes that maximise profit (EBIDTA) for the business.
This method helps isolate and examine the value of investments targeted at specific parts of the farm on the whole farm business, and could potentially offer analysis that will make best use of resources within defined boundaries, for targeted performance of ecosystem services delivery.