Experiments in globalisation, food security and land use decision making

Abstract

The globalisation of trade affects land use, food production and environments around the world. In principle, globalisation can maximise productivity and efficiency if competition prompts specialisation on the basis of productive capacity. In reality, however, such specialisation is often constrained by practical or political barriers, including those intended to ensure national or regional food security. These are likely to produce globally sub-optimal distributions of land uses. Both outcomes are subject to the responses of individual land managers to economic and environmental stimuli, and these responses are known to be variable and often (economically) irrational. We investigate the consequences of stylised food security policies and globalisation of agricultural markets on land use patterns under a variety of modelled forms of land manager behaviour, including variation in production levels, tenacity, land use intensity and multi-functionality. We find that a system entirely dedicated to regional food security is inferior to an entirely globalised system in terms of overall production levels, but that several forms of behaviour limit the difference between the two, and that variations in land use intensity and functionality can substantially increase the provision of food and other ecosystem services in both cases. We also find emergent behaviour that results in the abandonment of productive land, the slowing of rates of land use change and the fragmentation or, conversely, concentration of land uses following changes in demand levels.

Figure 1. Variation in productivity capitals across the modelled arena.

Crop productivity is shown on the left and natural capital on the right. Both are maximised on the right-hand-side of the arena in order to allow separation of agent types while generating competition for the most productive cells.

Figure 2. Baseline land use and supply levels results (Experiment 1) under constant levels of demand for services.

Land use maps are shown for for Experiments 1a (a) and 1c (b) along with the corresponding supply of food produced in each (c).

Figure 3. Baseline results (Experiment 1) following drop in demand for recreation.

Final land use maps are shown for Experiments 1b (a) and 1d (b), following a drop in demand for recreation. The corresponding levels of demand and supply of food and recreation services are shown in (c) and (d) respectively. The distribution of conservationist agents in capital space is shown for Experiment 1b in (e) and for Experiment 1d in (f). Uniform grey areas of capital space in (e) and (f) do not occur in the modelled arena.

Figure 4. Effects of variation in abandonment thresholds (Experiments 2 & 3) on response to drop in demand for recreation.

Final land use maps are shown for Experiments 2c (a), 2d (b), 3b (c) and 3d (d), showing the responses of conservationists to a drop in demand for recreation under different abandonment thresholds. Farmer agents have higher abandonment thresholds in Experiment 2 and conservationists in Experiment 3, respectively producing dispersed and concentrated patterns of conservationist land use.

Figure 5. Global and regional supply levels under decreased sensitivity to demand levels (Experiment 8).

Global supply of food (a) and recreation (b) under dynamic recreation demand levels in Experiments 8b and 8d, and regional supply of food (c) and recreation (d) in Experiment 8d. Decreased sensitivity to demand levels is modelled through exponential utility functions, and resulted in overproduction in the most productive regions. Red lines are demand levels, which are shown following the drop in recreation demand in (c) and (d).

Figure 6. Supply levels and land use maps following the introduction of multifunctional agents.

Supply of food in Experiment 10 under static demand (a) and dynamic demand for recreation (b), and final land use maps under global dynamic demand in Experiments 10b (c) and 11b (d), showing the difference in the response of conservationists to the drop in demand for recreation as their abandonment thresholds are varied.

Figure 7. Demand and supply levels with agent multifunctionality and reduced sensitivity to demand (Experiment 19).

Food supply under static demand in Experiments 19a and 19c (a) and nature supply under dynamic demand in Experiments 19b and 19d (b). Supply of services exceeded demand throughout Experiment 19 except for regionalised supply of recreation under static demand.

Figure 8. Agent locations in capital space in Experiment 19a.

High-intensity farmers (a), mid-intensity farmers (b), low-intensity farmers (c) and conservationists (d), showing appropriate distributions relative to capital levels. Uniform grey areas do not occur in the modelled arena.