Climate-related subsidies for CO2 absorption and fuel substitution: Effects on optimal forest management decisions.

This study investigates rational ways to optimize stand-level management decisions from an economic perspective to adjust alternative subsidies, aiming to reduce the CO2 level in the atmosphere and consequently, to mitigate the global warming impacts. An objective function consisting of two parts is used to maximize the current production value that forests represent and the value of forests under the effects of different types of subsidies intended to reduce CO2 levels. The optimal ways of adjusting stand-level management decisions are determined using a general comparative statics analysis, which takes into account alternative forms of climate-related subsidies. The optimal changes to stand-level management decisions are functions of the initial conditions of the stand of trees on which the decision will be made. The results have shown that there are one or two of the alternative forms of CO2 subsidies increase: if the initially optimal values of the stock level after harvesting {V1} is lower than the stock level that maximizes the sustainable yield {VMSY}, and the time interval between harvests {t} is sufficiently short, then the initially optimal value of V1 and t increase; if the initially optimal value of V1 is lower than VMSY, and t is sufficiently long, then the initially optimal values of V1 and t may vary or stay unchanged; if the initially optimal value of V1 is equal to VMSY, and t is very short, then V1 and t are not changed; if the initially optimal value of V1 is higher than VMSY, and/or t is sufficiently long, then the initially optimal values of V1 and t decrease. Our approach of providing decisions at the stand-level can be extended to the broader scales at forest landscapes to address the related challenges.

Alternative Modelling Approach to Spatial Harvest Scheduling with Respect to Fragmentation of Forest Ecosystem.

Fragmentation of the forests affects forest ecosystems by changing the composition, shape, and configuration of the resulting patches. Subsequently, the prevailing conditions vary between patches. The exposure to the sun decreases from the patch boundary to the patch interior and this forms core and edge areas within each patch. Forest harvesting and, in particular, the clear-cut management system which is still preferred in many European countries has a significant impact on forest fragmentation. There are many indices of measuring fragmentation: non-spatial and spatial. The non-spatial indices measure the composition of patches, while the spatial indices measure both the shape and configuration of the resulting patches. The effect of forest harvesting on fragmentation, biodiversity, and the environment is extensively studied; however, the integration of fragmentation indices in the harvest scheduling model is a new, novel approach. This paper presents a multi-objective integer model of harvest scheduling for clear-cut management system and presents a case study demonstrating its use. Harvest balance and sustainability are ensured by the addition of constraints from the basic principle of the regulated forest model. The results indicate that harvest balance and sustainability can be also achieved in minimizing fragmentation of forest ecosystems. From the analyses presented in this study, it can be concluded that integration of fragmentation into harvest scheduling can provide better spatial structure. It depends on the initial spatial and age structure. It was confirmed that it is possible to find compromise solution while minimizing fragmentation and maximizing harvested area.