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Forest landscape management is based on the premise that resource flows as well as biodiversity levels and ecosystem processes are determined by the array and spatial arrangement of forest conditions, i.e., spatial structure, and its change over time. This paper points out that a quantitative basis for measuring spatial structure is a prerequisite to implementing forest landscape management. Without such, structural objectives cannot be established nor can the understanding of spatial dynamics necessary to achieve structural objectives be mastered. This paper presents a comprehensive collection of measurements, some old and some new, organized in a hierarchical framework. The framework organizes structural measurements by geographical scale, i.e., landscape and patch, and within these by areal, lineal, and topological categories. The hierarchical framework is offered as a means to simplify interpretation of a rather large and complex set of measurements. Using this framework, the paper presents more than two dozen measurements. In each case, the measurements are discussed in terms of calculation algorithm, interpretation, and timber and (or) wildlife habitat context. The potential use of the measurements for quantifying landscape structure is demonstrated with an example. The paper concludes with a general discussion of the implications of the measurements presented for forest landscape management.

Sustainable forest management is driving the development of forest decision support systems (DSSs) to include models and methods concerned with climate change, biodiversity and various ecosystem services (ESs). The future development of forest landscapes is very much dependent on how forest owners act and what goes on in the wider world, thus models are needed that incorporate these aspects. The objective of this study is to assess how nine European state-of-the-art forest DSSs cope with these issues. The assessment focuses on the ability of these DSSs to generate landscape level scenarios to explore the output of current and alternative forest management models (FMMs) in terms of a range of ESs and the robustness of these FMMs in the face of increased risks and uncertainty. Results show that all DSSs assessed in this study can be used to quantify the impacts of both stand and landscape-level FMMs on the provision of a range of ESs over a typical planning horizon. DSSs can be used to assess how timber price trends may impact that provision over time. The inclusion of forest owner behavior as reflected by the adoption of specific FMMs seems to be also in the reach of all DSSs. Nevertheless, some DSSs need more data and development of models to estimate the impacts of climate change on biomass production and other ESs. Spatial analysis functionality need to be further developed for a more accurate assessment of the landscape level output of ESs from both current and alternative FMMs.

Currently, the integration of carbon and water values of forest ecosystems into forest management planning models has become increasingly important in sustainable forest management. This study focuses on developing a multiple-use forest management planning model to examine the interactions of timber and water production as well as net carbon sequestration in a forest ecosystem. Each forest value is functionally linked to stand structure and quantified economically. A number of forest management planning strategies varying in the amount of water, carbon, and timber targets and flows as constraints are developed and implemented in a linear programming (LP) environment. The outputs of each strategy are evaluated with a number of performance indicators such as standing timber volume, ending forest inventory, area harvested, and net present value (NPV) of water, timber, and carbon over time. Results showed that the cycling time of forest stands for renewal has important implications for timber, water, and carbon values. The management strategies indicated that net carbon sequestration can be attained at a significant cost in terms of foregone timber harvest and financial returns. The standing timber volumes and ending forest inventories were among the most important factors determining whether the forest constitutes a net carbon sink or source. Finally, the interactions among the forest values were generally found to be complementary, yet sometimes contradictory (i.e., negatively affecting each other), depending on the assumed relationship between forest values and stand structure.

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Spatiotemporal analysis of landscape dynamics is crucial in formulating an appropriate set of actions in landscape management. This paper presents a large scale analysis of the spatiotemporal structure of Istanbul, a highly urbanized city in Turkey, from 1971 to 2002 using forest cover type maps analysed with geographical information systems (GIS) and a spatial statistics programme. The quantitative evidence indicated that increasing population and expanding urbanization caused drastic changes to the temporal and spatial dynamics of land use/land cover pattern in Istanbul. There was a net increase of 5387Á3 ha in total forested areas (1Á0 per cent) due to mainly reforestation activities even though the population increased three times over a 31-year period. Increase in number of patches and decrease in mean patch size together demonstrated that the landscape developed into a more fragmented structure that would negatively affect biodiversity and the resilience of the ecosystems. In conclusion, plain increase in forest areas may not always be a favourable situation. The quality, composition and the configuration of forest landscape should also be analysed to present the dynamics of ecosystem in terms of ecological and economical sustainability over a longer time and larger area.

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