7Department of Animal Ecology, Swedish University of Agricultural Sciences, SE-901 83 Umeå Sweden

Keywords:
ecosystem and landscape forestry, sustainability, biodiversity, sustainable biomass production, water quality, forest management, socio-economics, planning

Abstract

EFERN, European Forest Ecosystem Research Network, was set up in 1996 as one result of the Ministerial Conferences on the Protection of European Forests in Strasbourg 1990 and Helsinki 1993 with the aim of promoting ecological research for sustainable forest management. Three plenary meetings were held, each with a specific theme. The results of these meetings have been documented in 10 chapters in a volume with the title "Pathways to the wise use of forests in Europe". The intention was also to give priorities for future forest ecosystem research. In accepting the idea that sustainability includes a multifunctional view of forests, there is a need to find ways of integrating classical forest ecosystem research with biodiversity, water quality and socio-economics. The balancing of the different interests in the forests can be done through planning. From this results also a choice of adequate management methods of the forest resources. The classical stand level in forestry requires now an additional scale - the landscape level. The aim with this paper is to present a concept which attempts to integrate the disciplines involved - ecosystem and landscape ecology and its components. Areas where research efforts are central are also mentioned.

Introduction

The major aim of European Forest Ecosystem Research Network, EFERN, has been to promote a pan-European network for co-ordinated research into forest ecosystems as expressed by the Ministerial Conference on the Protection of Forests in Europe, Strasbourg 1990 (von Weissenberg et al., 1993). An important step in that direction has been to review a number of concepts and topics in identifying scientific issues essential for maintaining and developing a sustainable forest management. In ten chapters (Andersson et al., eds. THIS ISSUE) a background is given by reviewing historical aspects on the use of forest land in Europe. Further fundamental aspects based on the properties and functioning of an ecosystem are also treated. Problems of the boreal, temperate, mountain and Mediterranean regions are likewise discussed.

In order to develop priorities for future forestry research with an ecological emphasis there are some facts to be considered. Sustainable forest management (Farrell et al., THIS ISSUE) is understood as a multiple use of the forest land in a way where future generations will have at least the same assets as we. In practising this kind of forestry the classical forest stand or forest ecosystem level research is no longer sufficient. The investigation of problems related to biodiversity and water quality as well as those linked to management practices will have to be conducted on a broader scale than previously - a landscape approach is needed.

The balancing of the multiple use of the forest landscape will require an integration of biological/ecological characteristics with socio-economic and socio-cultural ones. Therefore conventional stand-planning needs to be supplemented with landscape-based planning. This will require a close collaboration between planners, managers, ecologists and other specialists for the development of criteria which are linked to an understanding of the principles and aims of sustainable forest management.

Various management approaches such as multiple-use forestry, sustainable forestry, adaptive management or ecosystem-basis management have been proposed and applied. However, the successful management of forest ecosystems and landscape requires a thorough understanding of the complexity of interactions between forest management, the forest ecosystem and landscape functioning. An integration of ecological, economic and social factors in the planning process is essential.

We are living in a changing environment. Not only are we adapting our management practices in response to economic imperatives and technological development, but the physical and chemical climate is rapidly changing also, as a consequence of our combustion society. Climatic changes are occurring leading to unexpected and also rapid alterations in the environment in which our forests grow. We need to understand these changes and also be able to predict them if we are to adopt appropriate mitigation strategies.

With increasing basic knowledge of the forest ecosystem and the forest landscape, a closer mutual collaboration between stakeholders, planners, managers and scientists from a variety of disciplines will be needed in the future. It is a challenge for the next decade and onwards to develop and foster such a collaboration.

Based on the experiences of EFERN, we believe it is essential to contribute to an increased exchange and collaboration between disciplines, in order to give a new direction to forestry research. We suggest therefore the introduction of ecosystem and landscape forestry as a theme integrating the various components for developing a sustainable management of forest ecosystems and landscapes. The aim of this paper is to outline the components and possible content of such a theme as well as to indicate priorities of major scientific complexes/questions. Ecosystem aspects are discussed at several places in Andersson et al., eds. (THIS ISSUE). For definitions and nature of landscape ecology the reader is referred to Farina (1998) and Forman and Gordon (1986).

The aim of this paper is to present the components of ecosystem and landscape forestry and associated major scientific issues to be dealt with in future research and development. The paper does not claim to be fully systematic, nor to give a full coverage of all fields. It should be seen as an attempt to bring different disciplines together in an orderly way with the aim of introducing a holistic approach to sustainable forestry.

Forestry - some elementary considerations

The use of the forests and other elements in the landscape is driven by our human needs in local, regional and global perspectives. The way we use the forest as a natural resource is determined by a number of factors (Fig. 1). These factors, which in their character are social, economic, biological – ecological, can be seen as forces and constraints. The use of the forest is in many cases based on our historical legacy. Both the global and local economies as well as our social needs create a demand to use the forest. The need to control this use has been manifested for centuries in forestry acts and laws and in recent decades, in national and international protocols and conventions regulating the way we use the forest.

Figure 1: Basic knowledge and facts determining planning and management for sustainable forestry

To a greater extent than ever before, there is a demand to practise forestry in a dialogue where the need of the society, the public and the forest owners meet. The criteria for utilisation of the forest ecosystem and the landscape must be set by society. It is the role of the scientist to provide the best background for these criteria. As emphasised, there are now several aspects which need to be considered such as maintained biomass production, biodiversity, water quality, landscape values, tourism, economic benefits, social values etc. The balancing of the different interests is seen here as planning.

Our forestry system is complex. The criteria which are set or will be set are also dynamic as the needs of the society, the public as well as the owners, changes over time. Forestry acts are also changing over time as a consequence. Scientific understanding evolves too, providing the opportunity to develop better management alternatives.

Components of Ecosystem and Landscape Forestry - ELF

The major components of ecosystem and landscape forestry are seen in Fig. 2. Planning of forest ecosystems and landscapes is based on criteria - biological, ecological, hydrological, economic and socio-economic - derived from the best causal knowledge. Management is the tool which brings to reality the aspirations of the planning process. Forest management needs to develop or modify existing techniques and strategies so that a multi-purpose sustainable forestry can be applied. Planning and management practices must vary in scale as well as time depending on several factors, such as ownership, composition of landscape etc.

Figure 2: Major components of ecosystem and landscape forestry aiming at sustainable forest management

An understanding of land-use history and previous management are essential to the development of systems for sustainable forest management. The future development of ecosystems and landscapes is dependent not only on the management strategies we adopt, but also on changes in physical and chemical climate or air pollution and climate change.

Landscape-based forestry planning - balancing multiple interests

The concept of "sustainable forest management" (Farrell et al., THIS VOLUME) encompasses several criteria which may be used as guidance when managing the forests and the landscape. The planning process in this context is a balancing act, where different, sometimes contradictory, possible uses or values are dealt with or considered. These values and their relative importance vary over time and between different societies or countries. Therefore landscape-based forestry planning is a dynamic process for generating decision support for the balancing of the different dimensions out of the prevailing set of values and out of the present knowledge (Carlsson, 1998).

In order to generate a decision support it is essential to have a multidimensional description of the forest on a region/landscape level. This description needs to include the different components of the system as a basis for the evaluation of different criteria.

Furthermore analytical tools for handling the balance of different alternatives are needed. In order to make the whole process transparent to stakeholders and others an improved knowledge about the societal values assigned to different dimensions of the forest is needed, as well as an improved knowledge of the effects and consequences in the ecosystems of different human actions. This means that this planning component of the programme, to some extent, would perform the role of linking together results and knowledge generated in other parts of the programme.

Carrying out research in this area on a European scale means dealing with great regional diversity in ecosystem character and social systems, forest history and, ownership structure. This diversity increases the complexity of an integrated research effort.

Management practices

A basic principle of forest management is to focus on the protection, maintenance and/or restoration of the structure and functioning of the natural processes of forest ecosystems and its components at all landscape and time scales. In this way the management goal of developing long-term productive and sustainable forests can become a reality. Multi-functionality and aesthetics are self-evident constituents. Good management is founded on both the needs of society and the objectives of the forest owner.

By generating knowledge on the consequences of changes in land-use as well as on the influence of atmospheric and climatic changes on forest ecosystem health and productivity, a scientific basis for innovative forestry practice is at hand. Forest managers need therefore to intensify their analyses of forest health or vitality, enhance the use of predictive models, and make more frequently use of risk assessments.

The availability of long-term data significantly improves our understanding of the changes in the forest, its functioning and its potential behaviour under changing environmental conditions and the resulting risks. Knowing more about the effects of natural disturbances and forest management activities will ensure that our national and international policy debates are rooted in science. The challenge will also be to find ways to measure and monitor global environmental changes in European forest ecosystems with a view to shaping and sustaining forest ecosystems and landscapes.

For environmental resource managers, uncertainties are unavoidable because of natural ecological variability and our imperfect knowledge of ecosystems. In order to make political and management decisions, risk analysis becomes an important tool for forest/landscape management because it accounts for the uncertainty about states of nature. The assessment of risk associated with different management methods is essential in all regions. As an example the risks associated with mountain environments are growing rapidly with increasing resident and visiting populations, intensification and diversification of land uses, and the construction of infrastructure. Consequently, risk assessment and risk management are of great importance and call for an ecological basis to decision making in a world of uncertainty.

Biodiversity

The structures and components of the forests are different in different parts of Europe. However, key factors in the landscape determining biodiversity are structural components of the forests, such as dead wood, e.g. dead standing trees, snags, down logs, etc. Old trees, multi-layer canopy structure, uneven age structure as well as tree species composition, are other structures of importance, not least for the many species with specialised habitat needs.

There are some disturbance regimes which are common to the whole of the European continent. Fire as a disturbance process has been or is of importance both in the boreal parts of Europe and in the Mediterranean region. Another disturbance process of importance is the effect of grazing and browsing animals. This process is also quite evident both in the southern and northern part of the continent, although the herbivores influencing the vegetation are different, and the ecological effects are different. Another feature common to most of Europe, which certainly will influence biodiversity, at least at stand level, is the use of exotic tree species.

All over Europe the landscape and the forests are heavily influenced by man, although to different degrees and in different directions and patterns in geographic gradients. Thus, historical and socio-economic development in a country will influence the biodiversity of both stand, landscape and regional levels.

Planning, in a landscape perspective, will influence the possibility to maintain species dependent on patches or specific ecosystems in the landscape in such densities that the distance between suitable habitats will be shorter than the dispersal capacities of the species involved.

The management of forests must be carried out in the context of the whole landscape. However, management in the landscape perspective will take into account matters such as stand size, distance between forest units, an appropriate mix of different ecosystems. Nevertheless, management at stand level cannot be neglected as it is essential for the sustainability of forest ecosystems and the maintenance of long-term biodiversity. Development of management plans including information about for example, key structures of importance for biodiversity in different types of forests, should be possible.

Maintained or improved biodiversity of forests is a part of sustainable production. If this is accepted, there will be a connection between sustainable production and the socio-economic functions of a region. The reason is that maintained or even increased biodiversity will be a part of the attraction of a landscape.

Biodiversity is also connected to water quality, which to a great extent is influenced by forest management activities The way foresters treat water in the forest by for example ditching, will also influence the biodiversity in riverine forests along streams of different size.

However, there is also a connection between biodiversity and socio-economic functions in the other direction. As indicated, maintaining biodiversity in the landscape or province is certainly a value which will be regarded as a part of the socio-economic functions of importance in the future. The tourist industry based on eco-tourism will be much dependent on landscapes and regions where the biodiversity of fauna and flora will be managed in a sustainable way.

Sustainable tree biomass production

The ability of the forest to produce energy, fibre and timber as well as other commodities is fundamental to man’s existence (Farrell et al., THIS ISSUE; Piussi and Farrell, THIS ISSUE). This ability must be used and managed in such a way as to ensure the maintenance of sustainability. Our understanding of forest production and forest growth and thus sustainability is incomplete (Andersson et al., 1997; Andersson et al., THIS ISSUE). Present yield tables have not predicted the recent changes in boreal and temperate regions of Europe. It is argued that we need a causal understanding built upon a mechanistic knowledge of important processes.

For planning purposes there is a need to predict the effects of management strategies as well as different environmental changes. An increased understanding of plant/soil relationships as well as a better understanding of the biological part of the soil system is required. The spatial resolution in present soil sampling for chemical analyses may not be fully relevant in describing plant/soil relationships. It has been shown that the near-root environment deviates from the conditions described by bulk chemistry.

Sustainability of forest production is usually discussed from a long-term perspective. Long-term changes can lead to deficiency or even excess of mineral nutrients, which will affect the resistance of the tree or stand to frost and attacks of insects and pathogens. Recent advances in the understanding of tree vigour or vitality in relation to insects and pathogens are reviewed as a component for understanding production stability in short- and long-term perspectives.

Water quality

In many regions in Europe water resources in forests have become increasingly important to guarantee a drinking water supply. As a consequence, sustainable forest management must also integrate the various ecological and socio-economic benefits resulting from water resources.

Water as a factor for forest growth and calls for increased attention both in boreal, temperate mountain and Mediterranean regions. In this connection the importance of the vegetation cover in stabilising nutrient retention in the ecosystem as well as preventing erosion also calls for further attention. Likewise the importance of fire needs to be considered.

A multi-functional and sustainable forest management system should adequately consider the protection, maintenance and - where necessary - the restoration of water resources and aquatic ecosystems. However, conservation of water quality represents a highly integrative effort encompassing various temporal and spatial scales of forests as components of landscapes.

Water-related questions in forests inherently need to be addressed on the catchment scale. Nevertheless, the hydrological catchment approach has to be combined with the traditional stand-based nutrient cycling approach in order to obtain a reinforced understanding of underlying processes. Beside the study of interactions of water on its way through various types of forested catchments an experimental approach is essential. Short-term forestry operations (harvesting, thinning, road construction, (fertilisation/liming) have to be studied in model catchments as well as effects of changed silvicultural concepts (e.g. conversion of conifer plantations into age-structured mixed stands) on various time scales. Long-term silvicultural manipulation experiments on the catchment scale appear to be essential in order to generate controlled side-conditions for a successful interdisciplinary research. Modelling of water and element fluxes be developed further as a valuable tool to link processes on various temporal and spatial scales in catchments.

Socio-economic aspects

The multi-functionality of the forests implies that there are a number of interested parties involved, with different demands upon the forests. A most important link in applying sustainable forest management is therefore that the socio-economic aspects are considered and included in planning.

The overall question for the socio-economic analyses will be: how to combine or "balance" different forest functions (or goods or uses) so that their joint contribution to the regional welfare is as large as possible? Answering this question requires research in several fields:

Analyses of external effects: An external effect is at hand when one use of forest ecosystems/landscapes influences, either negatively, or positively, the possibilities for another use (without any market transactions between the uses). For example, both forest management practices and recreational activities may negatively affect biodiversity. On the other hand, there are positive external effects, e.g. when roads, built primarily for forestry activities are also used by recreationists for reaching remote areas. Negative as well as positive external effects can easily be seen in the forest. However, there is a lot of research to be done on analysing and measuring these effects, in a way that helps answer the overall question.

Estimation of values of different goods (or uses or functions): While timber is priced on the timber market, and its value is thus known, other forest goods have no market prices that adequately reflect their values. For example, The Right of Common Access in Nordic countries (or Switzerland) means that forest environments for many recreation activities attract no market price – even though they may have high recreation values. This is true also for forest landscape scenarios, which can be enjoyed even without any Right of Common Access. Furthermore, there are existence values associated with fauna and flora species. Such existence values are indicated by, among other things, the fact that many people are willing to pay money for saving endangered species. Without research aimed at value estimation of non-market-priced goods, and thereby making them more comparable to timber revenues, it is difficult to consider them properly in forest management programs. The number and quality of goods that the forests provide is, to a large extent, dependent on forest management practices. It is, thus, important to undertake research on different forest management practices with regard to their effects on environmental values.

Estimation of costs of environmental considerations: Research on how different forest management practices affect environmental values must be combined with research on the effects on forestry efficiency. Adaptations in forest management practices that increase the environmental value of the forests often involve costs for forestry in terms of, for example, lower timber volumes, more expensive cutting methods, etc. Furthermore, there may be costs associated with, for example, limiting recreational access to forest areas devoted to biodiversity. In reality, there are many "types" of costs associated with alterations in the use of forests. It is important to know more about these costs and to measure them in a way that reflects their true value

Cost-efficiency analyses: In principle, cost efficient environmental consideration in forestry means that a given cost spent on the environment improves the environmental quality as much as possible, or, that the cost for a given level of environmental quality becomes as low as possible. The problem in essence is to take into account economic and environmental effects simultaneously. Different environmental consideration measures must, thus, be compared with each other regarding effects on the economic viability of the forest enterprise (volume and quality of timber, logging costs, regeneration costs, etc.) as well as effects on the environment (recreation environment, biodiversity, etc.). Finding cost efficient solutions or environmental considerations is of vital importance for reaching a good combination of material and abstract forest values. At present there is very little research done in this sub-field.

Research within the sub-fields touched upon above can contribute to the development of forest policies and forest management practices that can balance different forest functions efficiently, which is, in turn, important for regional development in large parts of Europe. It is also clear that the research must have an interdisciplinary approach. Economists must work together with other social scientists (e.g. sociologists) as well as with natural scientists (e.g. ecologists and silviculturalists) – Smart solutions require better co-operation!

Research and development priorities

In order to apply sustainable forest management according to the principles of "Ecosystem and landscape forestry" on a European scale we can characterise the focal areas for research and development as follow:

Planning: to generate decision support for the balancing of the different dimensions of sustainable forestry. This support should take into account differences between ecosystems and their uses as well as social systems found on a European scale.

Forest management: to develop management strategies for self-sustaining (productive) forest ecosystems based on ecological knowledge of thresholds and disturbance regimes. We need to develop management strategies which satisfy the needs of the society without jeopardising the integrity and ecological stability of ecosystems and landscapes.

Biodiversity: to contribute to the understanding of the development of biodiversity patterns in different European landscape types, especially including the effects of socio-economic development and patterns in the landscapes studied.

Sustainability: to develop mechanistic understanding of forest growth/production based on research directed towards causal relationships of plant/soil and plant/pest organisms including climate, nutrients and water, especially considering long- term aspects.

Water quality: to develop a relevant understanding of how forest management affects water quality and plant growth for different purposes according to the need of the society.

Socio-economics: to combine or balance different forest functions (goods or uses) so their joint contribution to the regional welfare is as large as possible.

Conclusions

Sustainable forest management requires an adequate understanding not only of the forest ecosystem but also of the interaction between different disciplines. The planning process and finding the appropriate balance of different interests for the use of our forest and landscape resources will be vital to the achievement of the goal of sustainable forest management. The interaction with society and its norms will encourage scientists to develop criteria or standards to be met. An increased interaction between disciplines is expected, which will influence not only research but also education at different levels. Ecosystem and landscape forestry will be a key topic for the introductory decade of the new millennium.

Acknowledgements

The first author to this paper is grateful to the Forest Faculty of the Swedish University of Agricultural Sciences in Uppsala for having had the possibility to participate in establishing and follow up of a research programme "Managing forests for industrial products and environmental qualities" (Andersson, 1997). Colleagues Dr. L. Mattsson and Prof. Dr. O.Sallnäs are especially acknowledged for their willingness to contribute to a further development of the area. A first outline was made by Dr. R.Berger and Dr. H.Feichter, BOKU, Wien, Austria, Dir. O.Laroussinie, Forest Ecosystem Reasearch Co-ordination Centre, Paris, France, Prof. Dr. R. Hüttl and Dr. B-U. Schnieder, Brandenburger Technical University, Cottbus, Germany, Prof. Dr. P. Piussi, University of Florence, Italy and Prof. Dr. G. Scaracia-Mungozza, University of Tuscia, Viterbo, Italy (EFERN Newsletter 5). Constructive criticism and linguistic improvements to earlier drafts have been given and made by Professor E.P. Farrell, Dublin, Ireland, for which the authors are grateful.

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