Implementing individual tree-growth models for optimising the management of Pinus silvestris, Pinus nigra and Pinus halepensis any-age forests in Catalonia

 

Project leader

Palahí, Marc (marc.palahi(at)ctfc.es)

 

Schedule

13.12.2004 – 13.12.2007

 

Co-ordinator

Forest Technology Centre of Catalonia (CTFC)

 

Objectives

Forests dominated by Pinus sylvestris, Pinus nigra and Pinus halepensis occupy 70% of the forest area of Catalonia. Efficient and sustainable forest management and planning of these forests is very important to Catalonian forestry because of their economic, ecological and social role. The task of forest management planning is to show the optimal way to use forest resources in a way that the welfare of the forest owner (and/or the society) is maximised within the limits set by the legislation. The technological and methodological development of forest science allows for efficiently solving complex problems of forest management by using appropriate simulation tools and quantitative methods relying on numerical optimization. A key issue in the decision-making process of forest management planning is to predict forest stand development under different silviculture regimes. Growth and yield models are needed to predict the economic returns of a particular management schedule, but they can also provide key information about the dynamic change of less tangible attributes of forest, such as aesthetic value, or suitability of the forest for different animal species as well as to provide relevant information for fire risk control. Furthermore, finding the optimal stand management schedule can be a very complex problem because of the many interrelated variables that need to be found as well as the many potential objectives which can be important. In this context, simulation-optimization systems which combine the use of growth models and numerical optimization techniques offer the best possible tool to explore, to study and find the optimal silviculture regime for any specific situation and objectives. However, the majority of forests cannot be managed relying only on the stand-level approach because this often produces large fluctuations in annual harvests and revenues. Thus, in many cases the optimal stand treatment will depend and should be coordinated with the rest of the forest property, calling for forest-level management planning. In this context, simulation tools are critical to produce reliable information about alternative treatment schedules for the stands. This information can be later collected into a forest level optimization model, which is solved by combinatorial heuristic techniques. Results from a stand level simulation-optimisation system can be also used to generate silviculture instructions that can guide the forest level planning.

The main objectives of the project will be on:

 

1. Developing, evaluating and validating simulation tools for Pinus sylvestris, Pinus nigra and Pinus halepensis stands in Catalonia. The simulation tools will be based on:

a) Already existing individual-tree level models developed by the applicant team.

b) Static diameter distribution models to be develop within the project and based on the Spanish National Forest Inventory.

 

2. Generating silvicultural guidelines using the simulation tools developed as well as stand-level numerical optimization techniques. The use of simulation-optimisation systems will be demonstrated within the framework of traditional and emerging stand-level forest management problems (different situations and objectives; considering biodiversity, the risk of fires, etc.) for the species studied.

 

3. Developing new forest management models that may integrate traditional wood products as well as explicit stand and landscape level structural objectives related to ecological or recreational goals. This will be based on a quantitative approach that can take advantage of the simulation models developed earlier and new combinatorial optimization techniques (genetic algorithms, tabu search, simulated annealing, etc.). Several multi-objective forest management planning problems will be solve by using the whole chain of tools and techniques developed during the project.