Economic Evaluation of an Invasive Forest Pathogen at a Large Scale: The Case of Ash Dieback in France

Abstract

The invasion of a forest by a pathogen is a complex dynamic and spatial problem. The induced disturbances do not only reduce the present availability of the affected tree species but alter its future availability, population structure and distribution as well. These disturbances also have an impact on the prices of wood products via supply shocks, which, in turn, influence forest management choices, thus introducing feedback effects between market and ecological dynamics. The main objective of this paper is to evaluate the economic impact of an invasive pathogen at a large scale by integrating the biophysical and economic aspects of the invasion into a dynamic and spatially explicit setting. The analysis is developed using a modified version of the French Forest Sector Model (FFSM), a recursive partial equilibrium model, to which a specifically designed pathogen spread and mortality model have been coupled. We calibrated the model to represent the ash dieback invasion in France. Results showed that impacts are not homogeneous across regions and generally depend on the resource distribution, pathogen spread and market structure. We observed that the behavioural adaptation of forest managers (i.e. regeneration and harvesting choices) is a non-negligible component of the total standing volume loss.

Evolving Integrated Models From Narrower Economic Tools: the Example of Forest Sector Models

“…In addition, we note the relative absence of modelling journals, which could indicate a focus in published papers on results and policy implications rather than on methods and modelling tools. In the papers we reviewed, those published in modelling journals were focusing on the development of new "modules" within already established models [33,71,72] or developed new models [73] and contained detailed information about model specifications. However, the vast majority of papers reviewed contained much less information: given the large size and complexity of FSM, details about modelling techniques are usually published as separate books or technical reports [42,74].…”

“…Another common linkage established is with energy models [153] or IAM [114], which is an alternative to the specialisation of FSM described earlier. Our sample also included the use of model couplings to study regulation services, for example, with spread models for pathogens [72] or hydrology models [132]. This trend to develop "Economic Environment Integrated Models" is documented in the wider environmental modelling field, and is a welcome development since it enables performing new analyses [154].…”

Modelling for risk and biosecurity related to forest health

“…The assessment of the economic impact of forest PnPs is an extra layer that should be considered to have a full risk analysis. It should include not only the direct impact of PnP on the yield reduction and the quality loss, but the indirect impacts such as changes in prices, the demand and supply [77,78]. In addition, this economic impact should also rely on the costs and effectiveness of the risk mitigation options.…”

The Struggle of Ash—Insights from Long-Term Survey in Latvia

“…The economic merits of common ash are plummeting, but still it is highly ecologically important [2,3,5,20], hence the majority of the recent studies have addressed the potential for improvement of its resistance to the dieback [7,13,14]. Previous studies agree that, although high, the susceptibility of common ash to dieback is affected by intrinsic and environmental (stand, landscape, weather, etc.)…”