Publications

Population viability risk management (PVRM) provides a framework for explicitly including qualitative information about the possible outcomes of a management decision with regard to the viability of an endangered population in conservation management. Multi-criteria decision-making (MCDM) techniques enables managers to select the most preferred choice of action in a context where several criteria apply simultaneously. In that context a combined approach of the PVRM concept and a MCDM technique is presented for the development, evaluation and finally ranking of the in situ conservation strategies. We discuss the concept based on a case study for the maintenance of a gene conservation forest of an English yew population (Taxus baccata L.) in Styria, Austria. As part of the PVRM the analytic hierarchy process (AHP) is used to evaluate six conservation strategies with regard to the viability of the yew population. The viability of the population is evaluated based on the results of an analysis of the current environmental, social and economical state and a characterization of the ecological parameters of its population. The most significant risk factors (illegal cutting, browsing by game, tree competition, light availability and genetic sustainability) are structured and prioritised according to their impact on the viability of the yew population applying the AHP. Effects of the six conservation strategies on the viability of the yew population are determined through a qualitative assessment of the probability of a decrease of the population along with four different environmental scenarios. In this context strategy IV combining selective thinning, protection measures, game control with public relation activities seems to be the most effective alternative. The benefits of the combined approach of the PVRM concept with the AHP for the rational analysis of conservation strategies for this endangered tree species are discussed. © 2008 Elsevier B.V. All rights reserved.

Over the previous decade, sustainable forest management (SFM) has become a highly relevant topic both in forest and environmental policy. Criteria and indicators (C&I) are primarily used in implementing the principles of SFM at national, regional, and at forest management unit levels. In turning SFM from a conceptual framework into applicable guidelines at the operational scale, several limitations have to be acknowledged: (i) partial lack of knowledge, (ii) deficits about dependencies and feedbacks among system components represented by C&I, and (iii) knowledge gaps regarding impacts and related uncertainties. Several methodologies have been proposed to implement C&I-based SFM. Multi-criteria analysis is often used to analyze and evaluate multiple C&I approaches. This study compares two different multi-criteria analysis approaches: the analytic hierarchy process (AHP) with a hierarchical structure and the analytic network process (ANP) with a network structure. Comparisons are made for evaluating sustainable management strategies at forest management-unit level by using a C&I approach based on the Pan-European guidelines for SFM. AHP and ANP are used to compare four different strategic management options with a set of six criteria and 43 indicators. Differences in evaluation results between AHP and ANP are discussed, as well as strengths and weaknesses of both approaches for SFM. Needs and demands are derived for successful future applications in forestry decision-making. © 2004 Elsevier B.V. All rights reserved.

Forestry extension services in southern Austria currently provide forest resource management consultation for landowners. Given the complexity of analysis and selection of silvicultural treatment alternatives for Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) karst.) stands in this region, consultants have a need for computer-based analytical support. DSD v1.1 (Decision Support Dobrova) was specifically designed to meet this need. In close cooperation with local forest authorities, a generic model of the consultation process was developed. DSD v1.1 supports a planning process which covers the phases of decision-making: (i) identification of current states regarding site and stand conditions, (ii) identification of owners expectations and preferences regarding a set of objectives, (iii) selection and evaluation of management alternatives. The core concept is that relevant information regarding the characterization of alternatives is prefabricated and stored in a database. Various stand treatment programs for representative stands were simulated with a distance-dependent individual tree growth model. The user can link sites, species and stand treatment programs, costs and timber prices, and evaluate these decision alternatives with regard to his own goal preferences by means of an additive utility model which is based on the analytic hierarchy process. Reporting facilities of the software tool include on-screen graphs and tables as well as printed reports. The software is implemented in C++ as a client/server architecture with Oracle® as relational database management system. The process itself is fully encapsulated in the server utilizing the PL/SQL capabilities from Oracle®. Initial feedback from end-users has been encouraging. The software tool is robust and functional. Limitations are the current format of reports and missing on-line help and documentation services. Through its modular concept the DSD-framework can easily be adapted to other geographic regions. © 2005 Elsevier B.V. All rights reserved.

This, the second special issue on DSSs is entitled “Decision-Support Systems for Forest Management” presents contributions from a trans-disciplinary Conference on decision support in multiple-purpose forestry, held at the University of Natural Resources and Applied Life Sciences in Vienna, April 23–25, 2003. A major objective of the Conference was to review the “state of the art” in the field of decision support in forest management, bringing together experiences gained in the United States and Canada with the longer tradition of forestry and current approaches to DSSs for forest management in Europe. Participants from 28 countries presented the current state of knowledge in 70 oral presentations, including 6 keynotes, and 51 posters. Selected contributions from the Conference have been compiled in this special issue of Computers and Electronics in Agriculture and a companion issue of Forest Ecology and Management.

The development and application of a spatial decision support system (SDSS) for silvicultural planning in forests managed for sustained yield of water resources is presented. The implementation of core components of the SDSS is described. As an example, the development of a decision model for selecting the best silvicultural treatment option for stands Scheduled for natural regeneration is discussed. The decision problem is factorized into decisions on the future species mixture (GSO) and on an appropriate regeneration method (RM). A priori defined sets of alternatives (nine species mixtures, Seven regeneration methods) are evaluated with respect to a set of stand-specific partial management objectives (water production, timber production, conservation of biodiversity, recreation, protection against rockfall and avalanches) by further decomposing the partial objectives into decision Criteria. To circumvent the lack of quantitative knowledge on the Value of different species mixtures and regeneration methods with respect to the managemera objectives, pair-wise comparisons of decision alternatives based on qualitative expert knowledge are utilized to compute preference values. An additive multiple-attribute preference model is used to aggregate the preferences at different levels of the decision hierarchy. The combination of GSO and RM which simultaneously maximizes the expected utility and satisfies all Constraints of the forest decision maker is selected as the overall best solution. © 2001 Elsevier Science B.V.

In forest management planning emphasis is being placed not only on timber production but also on values such as recreation, amenities, wildlife and the role of forests in securing sustained water resources. In the mountainous terrain of Austria, forests additionally provide protection against soil erosion and natural hazards such as avalanches and rockfall. Forest managers are challenged by the task to transform these forest management objectives into silvicultural prescriptions for a particular stand, when considering appropriate future species mixtures or silviculture measurements.

Identification of management objectives at the stand level and evaluation of management practices which best meet these forest level goals require the development and application of models. Spatial decision support systems (SDSS) can be a valuable tool for analysis of such complex spatial decision problems in multiple purpose forest resource planning.

However, developing SDSS requires the cooperation of decision analysts and computer programmers. Quite often the lack of mutual understanding of other’s tools and methods, create communication problems that result in time-delays and errors. To overcome such limitations MapModels was developed. MapModels is a new and flexible tool for explorative data analysis and modeling of spatial decision problems.