Cristian D. Palma

Integrated spatial fire and forest management planning

Forest management planners usually treat potential fire loss estimates as exogenous parameters in their timber production planning processes. When they do so, they do not account for the fact that forest access road construction, tim- ber harvesting, and silvicultural activities can alter a landscapes vegetation or fuel composition, and they ignore the possi- bility that such activities may influence future fire losses. We develop an integrated fire and forest management planning methodology that accounts for and exploits such interactions. Our methodology is based on fire occurrence, suppression, and spread models, a fire protection value model that identifies crucial stands, the harvesting of which can have a signifi- cant influence on the spread of fires across the landscape, and a spatially explicit timber harvest scheduling model. We il- lustrate its use by applying it to a forest management unit in the boreal forest region of the province of Alberta in western Canada. We found that for our study area, integrated fire - forest management planning based on our methodology could result in an 8.1% increase in net present value when compared with traditional planning in which fire loss is treated as an exogenous factor.

Assessing the impact of stand-level harvests on the flammability of forest landscapes

The harvesting of forest stands can reduce landscape flammability by fragmenting fuel continuity in ways that make it difficult for fires to spread and by providing firefighters with fuel discontinuities they can use as anchor points for suppression operations. We describe a methodology for assessing the impact of harvesting designated forest stands on landscape flammability and expected losses. We combine assessments of the probability that fires will be ignited at any point on the landscape with probabilistic predictions concerning how long escaped fires will burn and how they will spread. Shortest path methods are used to identify critical paths that link potential ignition points with values at risk. We then rank stands with respect to their ability to disrupt those critical paths and thereby reduce landscape flammability and fire losses. We describe how we applied our methodology to a 12 964-ha forested area of boreal forest in the province of Alberta, Canada. Our results indicate that the crucial stands in our study area, those that have the most significant impact on landscape flammability and fire loss, tend to be those that are flammable and located on or close to critical paths that link areas where fires are most likely to occur with values at risk.

A comparison of optimization models for lumber production planning

El desempeno de un aserradero depende principalmente de como las trozas son aserradas para producir las piezas de madera demandas por los clientes. Para hacer esto, el planificador de la produccion debe decidir que patrones de corte deben ser aplicados a trozas de distintos tamanos. Los modelos de optimizacion han ayudado a tomar estas decisiones, pero solo se han considerado como objetivo de estos modelos la maximizacion de beneficios y la minimizacion de costos. En este articulo se formula un modelo de planificacion de la produccion de aserraderos, se aplica a un problema real, y se comparan las decisiones del planificador con las decisiones generadas por distintas funciones objetivo usadas en el proceso de optimizacion: las dos ya mencionadas ademas de la minimizacion de excedentes, minimizacion del numero de trozas y minimizacion del tiempo de produccion. Solo los modelos de maximizacion de beneficio y minimizacion de excedentes mostraron retornos positivos. Aunque la solucion actual del aserradero tambien mostro un retorno economico positivo, el mismo retorno fue obtenido con significativamente menos recursos, usando el modelo de minimizacion de excedentes. El efecto de diferentes funciones objetivo en los indicadores de produccion es discutido.