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38 papers found.
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Using ALS raster data in forest planning

Raster type of forest inventory data with site and growing stock variables interpreted for small square-shaped grid cells are increasingly available for forest planning. In Finland, there are two sources of this type of lattice data: the multisource national forest inventory and the inventory that is based on airborne laser scanning (ALS). In both cases, stand variables are...

Optimized cellular automaton for stand delineation

Forest inventories based on remote sensing often interpret stand characteristics for small raster cells instead of traditional stand compartments. This is the case for instance in the Lidar-based and multi-source forest inventories of Finland where the interpretation units are 16 m × 16 m grid cells. Using these cells as simulation units in forest planning would lead to very...

Influence of size and shape of forest inventory units on the layout of harvest blocks in numerical forest planning

The purpose of this study was to assess the effect of using alternative types of forest inventory units (FIUs) in multi-objective forest planning. The research was carried out in a Mediterranean forest area in central Spain. The study area was divided, alternatively, into pixels (square cells) and segments of two different sizes (small and large), which represented the tested FIU...

Using past growth to improve individual-tree diameter growth models for uneven-aged mixtures of Pinus sylvestris L. and Pinus nigra Arn. in Catalonia, north-east Spain

TRASOBARES 1 Timo PUKKALA 0 0 Faculty of Forestry, University of Joensuu , PO Box 111, 80101 Joensuu , Finland 1 Centre Tecnològic Forestal de Catalunya , Pujada del seminari s/n, 25280, Solsona , Spain

Using past growth to improve individual-tree diameter growth models for uneven-aged mixtures of Pinus sylvestris L. and Pinus nigra Arn. in Catalonia, north-east Spain

TRASOBARES 1 Timo PUKKALA 0 0 Faculty of Forestry, University of Joensuu , PO Box 111, 80101 Joensuu , Finland 1 Centre Tecnològic Forestal de Catalunya , Pujada del seminari s/n, 25280, Solsona , Spain

Optimizing the debarking and cutting schedule of cork oak stands

Key message Optimal management of cork oak forest stands was analyzed for different site indices and cork growth rates. Optimal debarking intervals varied during the rotation and were sometimes shorter or longer than the officially recommended range of 9–14 years. ContextQuercus suber L. is one of the most important multipurpose tree species in the Mediterranean area. Its main...

Optimal nitrogen fertilization of boreal conifer forest

Background Forest fertilization offers a means to increase the production of renewable resources. Nitrogen is the most common fertilizer in boreal upland forests. There is plenty of research on the effect of nitrogen fertilization on volume growth, but less research on the optimal timing of fertilization and optimal management of fertilized stands. Methods This study used...

Which type of forest management provides most ecosystem services?

Background Forest ecosystems are increasingly seen as multi-functional production systems, which should provide, besides timber and economic benefits, also other ecosystem services related to biological diversity, recreational uses and environmental functions of forests. This study analyzed the performance of even-aged rotation forest management (RFM), continuous cover forestry...

Optimizing continuous cover management of boreal forest when timber prices and tree growth are stochastic

Background Decisions on forest management are made under risk and uncertainty because the stand development cannot be predicted exactly and future timber prices are unknown. Deterministic calculations may lead to biased advice on optimal forest management. The study optimized continuous cover management of boreal forest in a situation where tree growth, regeneration, and timber...

Which trees should be removed in thinning treatments?

BackgroundIn economically optimal management, trees that are removed in a thinning treatment should be selected on the basis of their value, relative value increment and the effect of removal on the growth of remaining trees. Large valuable trees with decreased value increment should be removed, especially when they overtop smaller trees.MethodsThis study optimized the tree...

Modelling of the spread of a potential invasive pest, the Siberian moth (Dendrolimus sibiricus) in Europe

Background The Siberian moth (Dendrolimus sibiricus) (SM) defoliates several tree species from the genera Larix, Picea and Abies in northern Asia, east of the Urals. The SM is a potential invasive forest pest in Europe because Europe has several suitable host species and climatic conditions of central and northern Europe are favourable for the SM. Methods This study developed a...

Height increment of understorey Norway spruces under different tree canopies

Background Stands having advance regeneration of spruce are logical places to start continuous cover forestry (CCF) in fertile and mesic boreal forests. However, the development of advance regeneration is poorly known. Methods This study used regression analysis to model the height increment of spruce understorey as a function of seedling height, site characteristics and canopy...

Stand management optimization – the role of simplifications

BackgroundStudies on optimal stand management often make simplifications or restrict the choice of treatments. Examples of simplifications are neglecting natural regeneration that appears on a plantation site, omitting advance regeneration in simulations, or restricting thinning treatments to low thinning (thinning from below).MethodsThis study analyzed the impacts of...

Evaluation of different approaches to individual tree growth and survival modelling using data collected at irregular intervals – a case study for Pinus patula in Kenya

BackgroundThe minimum set of sub-models for simulating stand dynamics on an individual-tree basis consists of tree-level models for diameter increment and survival. Ingrowth model is a necessary third component in uneven-aged management. The development of this type of model set needs data from permanent plots, in which all trees have been numbered and measured at regular...