Estimating impacts of climate change policy on land use: an agent-based modelling approach.
Bottom Line: The model utilises a partial equilibrium economic model and an agent-based decision-making framework to explore how the cumulative effects of individual farmer's decisions affect farm conversion and the resulting land use at a catchment scale.Key results from the model show that farm net revenue is estimated to increase over time regardless of the greenhouse gas price.Higher GHG prices provide a greater net reduction of emissions.
Affiliation: Landcare Research, Auckland, New Zealand.
Agriculture is important to New Zealand's economy. Like other primary producers, New Zealand strives to increase agricultural output while maintaining environmental integrity. Utilising modelling to explore the economic, environmental and land use impacts of policy is critical to understand the likely effects on the sector. Key deficiencies within existing land use and land cover change models are the lack of heterogeneity in farmers and their behaviour, the role that social networks play in information transfer, and the abstraction of the global and regional economic aspects within local-scale approaches. To resolve these issues we developed the Agent-based Rural Land Use New Zealand model. The model utilises a partial equilibrium economic model and an agent-based decision-making framework to explore how the cumulative effects of individual farmer's decisions affect farm conversion and the resulting land use at a catchment scale. The model is intended to assist in the development of policy to shape agricultural land use intensification in New Zealand. We illustrate the model, by modelling the impact of a greenhouse gas price on farm-level land use, net revenue, and environmental indicators such as nutrient losses and soil erosion for key enterprises in the Hurunui and Waiau catchments of North Canterbury in New Zealand. Key results from the model show that farm net revenue is estimated to increase over time regardless of the greenhouse gas price. Net greenhouse gas emissions are estimated to decline over time, even under a no GHG price baseline, due to an expansion of forestry on low productivity land. Higher GHG prices provide a greater net reduction of emissions. While social and geographic network effects have minimal impact on net revenue and environmental outputs for the catchment, they do have an effect on the spatial arrangement of land use and in particular the clustering of enterprises.
No MeSH data available.
Related in: MedlinePlus
Mentions: We project that the area of both Dairy and Forest enterprises will increase over time in both the baseline and all of the GHG price scenarios (Fig 4). In the baseline, mean Dairy area increases from the initial 16,900 ha to 106,472 ha over the 50-year period (with a 95% Confidence Interval (95% CI) of 1,899 ha). Although expansion this seems large, it is not unrealistic. First, the area of Dairy land in Canterbury increased by 172% between 1996 and 2008, and it is projected to expand by an additional 51% by 2020 . Second, the Hurunui and Waiau catchments have already witnessed additional conversion to Dairy over the last 5 years, as forests in the highly-productive flat areas of the catchment reach harvest age. Third, there are ongoing discussions of implementing the Hurunui Water Project, which would expand the area of irrigated land by an additional 41,500 ha, bringing the total irrigated area of the Hurunui and Waiau catchments to over 72,000 ha . Therefore our projections are within what may be expected to occur in this catchment over the next 50 years.
No MeSH data available.