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Since the 1960's, Portugal has been affected by profound land use/land cover changes, which have boosted fuel continuity and fire-proneness nationwide. Within this context, the assets of pulp paper companies are exposed to large wildfires, which may cause severe economic losses. Wildfire simulations can help to scenarize and anticipate fire spread, contributing to efficiently allocate resources to protect values at risk. To test this framework, we assessed wildfire hazard in a 115,000 ha landscape, including 3,720 ha owned by two companies, with the aim of identifying the management units most exposed to large wildfires and the ones most at risk. We used Minimum Travel Time algorithm to estimate Burn Probability (BP), Fire Size (FS) and Conditional Flame Length (CFL). Wildfire hazard and exposure were assessed at the landscape-level; risk was estimated in production eucalypt plantations, by combining the annual BP with potential economic losses, based on management costs, loss of revenue and salvage wood. Our results showed that eucalypt plantations not managed by the companies represent a major threat to their patrimony. Industrial plantations with ages between 6 and 9 years have proven the most exposed. Very large wildfires (≥5,000 ha) can potentially spread in 53 % of the landscape, affecting 75 % of young eucalypt (<5 years) area. The 90th percentile of the risk ranges from 213 to 429 €ha−1 year−1 (9.6 % of production eucalypt area). This work resulted in a flexible methodology, replicable in Mediterranean regions with similar landcover. The information produced can provide additional guidance for wildfire prevention and risk management. [Display omitted] • We used MTT algorithm to simulate large wildfires under extreme weather conditions. • We assessed the exposure of pulp companies' management units to large wildfires. • We estimated risk as annual economic losses in production eucalypt plantations. • The 9.6 % of production eucalypt is associated with the 90th percentile risk. • We provided additional guidance for wildfire prevention and risk management. [ABSTRACT FROM AUTHOR]

Abstract: SIMPLOT is a forest simulator for eucalyptus mainly driven by wood demand. It was developed to predict the evolution of the eucalyptus plantations in Portugal by combining forest inventory data with growth models taking into account the effect of different drivers such as wood demand, hazards occurrence and percentage of land use changes. The use of simulators for scenario analysis can be a powerful tool to explore policy options and to illustrate the consequences of different management alternatives. In the past years Portugal has been marked by extremely severe forest fires of great environmental impact. This paper shows simulation runs for two main scenario lines: the wood demand line and the wildfires line. In the first one, the simulator is used to identify a reasonable wood demand out of three different wood demands combined with a low/medium intensity fire scenario. The selected wood demand combined with three fire scenarios of increasing severity and a fourth one disregarding the existence of recent severe wildfires builds the second scenario line. The purpose of this study is to evaluate the impact of different magnitudes of forest fires occurrence on the sustainability of eucalyptus plantations starting with NFI data gathered in 1997 during a horizon of 28 years. The simulations reflect a constant level of afforestation and deforestation and assume that no changes took place between different management alternatives. These simulations provide some insight on the impact of different wood demand and different magnitudes/frequency of severe wildfires: it is not only the number and magnitude of severe wildfires that make a difference, but it is also the number and magnitude of medium wildfires that follow an extremely severe one. Furthermore, the inter-annual variability of wildfire occurrence affects carbon stock and carbon sequestration in a different way. The occurrence of severe wildfires has an immediate effect on carbon sequestration. The lower values are registered in the same year in which the most severe wildfires occur. On the other hand, the occurrence of severe wildfires has more permanent consequences on carbon stocks than on carbon sequestration. The more severe and numerous are the wildfires the more difficult and at long-term will be to recover the carbon stocks in the forest. Results have also shown that if a higher wood demand compatible with the expected increase of pulp industry capacity would have been considered this would have had drastic impacts on eucalyptus forest sustainability due to overharvesting in order to meet the desired wood demand. [Copyright &y& Elsevier]

• Modeling the impact of defoliation on tree growth is an important tool for Integrated Pest Management (IPM). • A 3-PG based simulator was developed to integrate a Gonipterus platensis species-specific defoliation module. • Different scenarios of defoliation intensity under varying site conditions were simulated. • Wood volume losses of 74% and 85% were predicted for defoliations of the upper third of canopy of 75% and 100%, respectively. Growth losses due to insect defoliations are difficult to estimate. The lack of appropriate tools that account for defoliations in growth simulations makes difficult the task of forest managers to project growth, and thus, the expected economic income. The present work integrates defoliations in the 3-PG forest growth model in order to provide a tool that allows forest managers to estimate Eucalyptus globulus stands growth losses under a set of defoliation scenarios by simulating attacks of the Eucalyptus snout beetle Gonipterus platensis. To mimic these attacks, different amounts of the upper third of the canopy were removed, from 0 to 100%, depending on the scenario intensity, and considering only spring season attacks or both spring and autumn attacks in the same year. A set of E. globulus virtual stands, representing a range of site productivities, were submitted to constant yearly consecutive defoliations since age 2 up to 10. Simulation results showed that, for scenarios that removed 50, 75 and 100% of the upper third of the canopy, volume losses averaged 54, 74 and 83%, respectively, at age 10 with just the spring attack, reaching 69, 82 and 88%, respectively, with also the autumn attack. Removing only 25% of the upper third of the canopy produced relevant losses only if the stands were attacked in both seasons. Lighter defoliations tested seemed to have a marginal effect on stand growth regardless of site quality. The tool was also used to evaluate a field assessment methodology of G. platensis defoliation attacks on a set of real stands by comparing observed and estimated volumes at age 10. Estimations showed increasing volume losses with increasing defoliation intensities. When evaluating the field assessment methodology, results suggest that a single field visit to assess the G. platensis attack level in the whole lifetime of a stand is insufficient to make reliable growth loss estimations. The integration of the impact of defoliations in the 3-PG growth model revealed to be potentially useful as a forest management decision tool. [ABSTRACT FROM AUTHOR]