INTRODUCTION - GLOBAL TO LOCAL: ECOLOGICAL LAND CLASSIFICATION R I C H A R D A. SIMS Canadian Forest Service - Ontario Region, Natural Resources Canada, P.O. Box 490, Sault Ste. Marie, Ontario, P6A 5M7, Canada I A N G.W. CORNS Canadian Forest Service - Northwest Region, Natural Resources Canada, Edmonton, Alberta, T6H 3S5, Canada and KAREL KLINKA Department of Forest Sciences, University of British Columbia, Vancouver, British Columbia, V6T 1Z4, Canada

Abstract. Ecological Land Classification (ELC) is a scientific endeavour which attempts to organize, stratify and evaluate ecosystems (and complexes of ecosystems) for the purposes of land resource management. Since ecosystems themselves are not easily defined in practical terms, ELC is likewise not a trivial concept. Nonetheless, ELC is a prerequisite for ecosystem management and the conservation of biological diversity simply because ecosystems must be described, characterized and spatially-located before they can be managed. Regarding the current status and future direction of ELC, mainly in relation to forest management: 1) approaches to ELC construction and utilization have shifted considerably over the past 2 decades; 2) there appears to be a current consensus regarding basic approaches to ELC; 3) spatial scale is a critical variable that must be addressed by ELCs; 4) ELCs must strive to more directly address management objectives; 5) natural ecosystem functions need to be better integrated within ELC frameworks; and, 6) the need for quality, georeferenced ELC-related data will continue to grow.

1. Defining "Ecological Land Classification" According to a classical and widely-quoted scientific definition, ecosystems are "living organisms interacting with each other and with their physical environment, usually described as an area for which it is meaningful to address these interrelationships" (Tansley, 1935). In other words, as Rowe (1996 (this volume)) succinctly notes, ecosystems are not randomly placed on earth. Whole or complete ecosystems are those whose boundaries reflect ecosystem pattern, as well as population processes and patterns. Practicing ecologists typically use a more pragmatic interpretation than that suggested by Tansley, which instead recognizes ecosystems as geographically-discrete entities which exist at certain implied levels of resolution, coincident more-or-less with the levels at which management and human intervention typically occur. In addition, this definition also typically embodies a definable and measurable suite of ecological conditions which are relevant to a collection of organisms (Salwasser Environmental Monitoring and Assessment 39: 1-10, 1996. ~) 1996 Kluwer Academic Publishers. Printed in the Netherlands.

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and Pfister, 1994; Crow, 1994). In this sense, ecosystems represent tangible, identifiable and modal sets of vegetational and abiotic conditions (Swanson and Franklin, 1992; Udo de Haes and Klijn, 1994). While they can exist at any scale, the most common usage is in the localized sense, referring to a distinct and coherent community of organisms occurring within a uniform physical environment (Slocombe, 1993). Ecological land classification (ELC) is the scientific endeavour that, for various management purposes, permits the organization and stratification of ecosystems and ecosystem complexes. Since the definition of the term "ecosystem" is itself somewhat problematic, it is not surprising that arriving at a widely-accepted definition and concept of ELC is also difficult (Udo de Haes and Klijn, 1994). As we have used it here, ELC is more of a combination of science and art which attempts to deal with the definition, recognition and representation of ecosystems (mainly, but not exclusively, land-based ecosystems) across gradients of both space and time. ELC is often, but not always, considered in terms of hierarchically-nested groupings of spatial polygons or definable-area units (Rowe, 1961; Urban et al., 1987; King, 1993; Zonneveld, 1994). In practical terms, ELC means thinking integratively and multi-dimensionally about ecosystems and their biotic and abiotic components (e.g., soils, water, plants, air, animals, and all of their interactions) within a flexible but ordered framework that, hopefully, can be related to management planning (Klijn, 1994a). Regardless of the definition, the end-products of ELC are context and some (spatiallybased) rule-sets for the design, practice, evaluation and iterative improvement of ecosystem-based sustainability, the conservation of biological diversity, and integrated resource management. ELCs are capable of addressing, in a far more comprehensive manner than now-outdated single-resource surveys, many critical conservation and environmental policy matters (Zonneveld, 1994). Because of this, ELC is a prerequisite for the evaluation of difficult trade-off decisions regarding resource issues.

2. ELC as a Context for Ecosystem-Based Forest Management

There have been a number of recent activities and legislation, in particular in the USA and Canada, directed towards the formal implementation of sustainable resource management practices using ecosystem-based approaches (e.g., see Francis, 1993; B ormann et al., 1994a; Grumbine, 1994; Larsen, 1994; Kaufmann et aL, 1994; Jordan and Uhlig, 1994; Canadian Forest Service, 1995). Ecosystem management, according to a recent definition by the US Forest Service (Kaufmann et al., 1994), is: "the use of an ecological approach that blends social, physical, economic, and biological needs and values to assure productive, healthy ecosystems." The concept goes hand-in-hand with that of conservation of biological diversity, that is, ensuring that genetic, species, community-level and landscape-level bio-

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logical variabilities are protected and maintained (e.g., Mann and Plummer, 1993; Salwasser and Pfister, 1994; Crow et al., 1994; McKenney et al., 1994). Currently, the concept of ecosystem management is being addressed in practical terms via a redefinition of existing forest management units, in concert with an "ecosystem approach" that requires us to develop and then build upon the best possible ecosystem-based science (Booth et al., 1993; Bormann et al., 1994a; Grumbine, 1994; Kaufmann et al., 1994; Urban, 1994), including that embodied in ELC. The current trend in forest management is towards ecosystem management, but the concept remains fuzzy and difficult to envisage (Bormann et al., 1994b; Larsen, 1995). Over the past century, forest management in North America has drifted or evolved through a number of major stages: 1) unchecked resource extraction in the early years, 2) limited regulation, mainly of uses which clearly lead to undesirable consequences, 3) sustained yield management focussed upon a few desired products, and, 4) a relatively recent and rapidly-growing focus on sustainable ecosystem management (Kimmins, 1987). An ecosystem management approach addresses the well-being of the ecosystem, which is acknowledged as providing many goods and services. This means balancing commodity and environmental objectives through the judicious application of resource management based upon: 1) current ecological understanding; 2) the realistic limitations of the resource base; and, 3) societal expectations, including (but clearly not limited to) those expressed in federal and provincial legislation (Swanson and Franklin, 1992). Forestry practices in the USA and Canada have been and continue to be on an evolutionary course. There is not now, nor will there ever be, a simple set of prescriptions for multiple use, multiple value management of complex ecosystems. Ecosystem management needs to be considered as a "direction", and not necessarily an achievable end-point (Holling, 1978; Waiters and Holling, 1990; Kaufmann et al., 1994). If ecosystem management is to be properly implemented, it must rely on the continued input of scientific and technical information (including that provided by ELC), but placed in context with evolving economic, political and social realities. The strategy should be to use what knowledge we have of natural ecosystems to develop practices of sustainable ecosystem management. An important part of forest ecosystem management is to maintain flexibility so there remain future opportunities to manage for what are currently vague, poorly understood or unknown ecological objectives. For many foresters, the critical part of the debate embodied in ecosystem management has hinged upon the balance between timber production and the tradeoffs required to preserve natural ecosystems. Consequently, there is an urgent need for a better understanding and a clearer articulation of non-timber values. ELC approaches that are currently being developed and tested will assist forest managers in addressing and better dealing with such conflicts. Continued forest ecosystem-based ELC research has a pivotal role to play in changing the way forest resources are managed. There is a need to integrate "full

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ecosystem" studies within an ELC framework so as to better consider habitat structure, food resources for aquatic and terrestrial wildlife, disturbance regimes and nutrient cycling. Old growth, coarse woody materials, below-ground organisms, and the dynamics of carbon and nutrient budgets are subjects that must be better addressed within an ELC context, so that ecosystem management can provide viable long-term solutions (Bormann et al., 1994b; Kaufmann et al., 1994; Simberloff, 1994). Forest management has always been and continues to be a form of active experimentation. Resource managers and scientists cannot claim to know with certainty what the end-results of various forest management strategies will be, let alone the effects upon those ELC units that are involved in ecosystem management there is simply insufficient experience and documented knowledge about these natural systems and their ecological responses to harvesting and related activities. As Waiters and Holling (1990) note, "every major change in harvesting rates and management policies is in fact a perturbation experiment with a highly uncertain outcome, no matter how skilful the management agency is in marshalling evidence and arguments in support of the change." This notion places particular pressure on ELC approaches to be as flexible and open-ended as possible, because inevitably "course-corrections" to ecosystem management approaches will need to be made; rigid frameworks will not be adaptable for longer-term requirements or new considerations as they arise.

3. Directions Arising from the Global to Local: ELC Conference This collection of 43 papers arose out of an intemational Global to Local: Ecological Land Classification conference that was held August 15-18, 1994, in Thunder Bay, Ontario, Canada. The 4-day event (2 days of presentations, followed by 2 days of field tours) was hosted by the Canadian Forest Service and the Ontario Ministry of Natural Resources, in association with the International Union of Forest Research Organization (IUFRO) Working Group S 1.02.06 (Site Classification and Evaluation). The conference was planned and overseen by the Canadian Forest Service's Ecological Land Classification Steering Committee. Objectives of the conference were to: 1) bring together and stimulate interaction among researchers and users of ELC systems; 2) inform scientists, technicians and managers about the different ELC approaches used in Canada and elsewhere; 3) explore new applications for ELC in the areas of ecosystem dynamics inventory and modelling; 4) emphasize linkages between ELC and related technologies; and, 5) identify critical areas requiring further research and development. Over 275 scientists, resource managers, consultants, educators, students and planners, from 11 nations, attended the conference. The format included plenary, break-out, and poster sessions, organized to reflect the broad spectrum of considerations related to ELC. Approximately 100 papers (oral plus poster) were

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presented by land classification researchers and practitioners from North America and around the world. Several optional post-meeting field tours, highlighting vegetation, wildlife, soil, geological and terrestrial science studies, allowed participants to investigate applied ELC concepts in Northwestern Ontario. The conference also featured three keynote presentations on Ecosystems and Land (Dr. J. Stan Rowe, University of Saskatchewan, Canada), Ecological Regionalizations (Dr. Robert G. Bailey, US Forest Service, Colorado, USA), and Balancing Demands for the Land: A Triad Approach to Land Use (Dr. Malcolm L. Hunter, Jr., College of Forest Resources, University of Maine, Orono, Maine, USA). During the Closing Plenary Session, some of the main themes and outputs of the Global to Local: ELC conference were identified and summarized by 3 rapporteurs (Mr. Don Prettyman (Natural Resource Services Ltd., Duluth, Minnesota), Mr. Jim McLean (Ontario Ministry of Natural Resources, Sault Ste. Made, Ontario), and Dr. Ian Corns (Canadian Forest Service, Edmonton, Alberta)). Following is a brief synopsis of some of their plus our own impressions regarding the current status of ELC. Approaches to ELC construction and utilization have shi3~ed considerably over the past 2 decades. There has been a convergence of ELC approaches, and this has generally involved the coming together of "vegetation-based" versus "soilsbased" classification approaches, and the emergence of more highly-integrated ELC products (Rowe and Sheard, 1981; Rowe, 1992). Concurrent with this trend, the variety of themes and topics for which ELC products are needed have grown considerably. In the past, land classifications were developed for single purposes (e.g., timber production, recreation potential or agricultural soil survey), and as such, land areas that were not suited to the particular purpose at hand (e.g., non-forested lands, lands with no recreational value, or non-agricultural lands) were not classified. Contemporary thinking, by contrast, recognizes that classifications should be applicable for all land (and water) areas and be suitable for a wide range of potential users (Rowe and Sheard, 1981). Taxonomic (e.g., field guides) versus cartographic (e.g., site mapping) approaches to ELC are also no longer viewed as diametrically opposing concepts in ELC, as was the case in the past. Over the past several years, data collection approaches have become more comprehensive and far more sophisticated. Analytical and interpretation tools have evolved to the point where Geographic Information Systems (GIS) and other computerized approaches are permitting detailed and data-intensive model development, cross-scale analyses and interpretations, and the integration of spatial and non-spatial databases (e.g., McKenney et al., 1996 (this volume)). There appears to be a current consensus regarding basic approaches to ELC. For example, the US Forest Service's multi-scale approach to the determination of map units (e.g., Bailey et al., 1994; McNab and Avers, 1994), especially at macroand meso-scales, is one approach that is receiving wide acceptance. The Canadian Committee for Ecological Land Classification's hierarchical system (e.g., Wiken

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et al., 1981; 1993; Marshall and Smith, 1996 (this volume)) has also become widely accepted in Canada. Consensus on philosophy, approach and methodology for classification will allow us to move more quickly towards the mapping of ecosystems at finer and finer levels of resolution; such maps are urgently needed by land managers. When some of the first ELCs in North America were being developed about 20 years ago, there was considerable optimism that these techniques would have immediate use and application. Unfortunately, these early products were often found to be cumbersome and sometimes unworkable, and they were incompatible in approach, scale and detail, so that comparisons from area to area were very difficult. At that point, land resource managers were not convinced that ELC could be beneficial, and while they agreed that ELCs were perhaps "nice to have", they were not necessary for doing their jobs, In the past decade, ELC as a scientific endeavour has "come of age" and important contributing factors have been the move towards standardization of ELC approach, and growing requirements for the types of comprehensive ecosystem-based information that an ELC can provide. Resource managers must now have - close at hand - detailed, in-depth knowledge on many scientific components for an area. Moreover, their legal responsibility for proper management of the resource is far more specifically-defined and they are considered professionally accountable to the public, industry and environmental groups for their management decisions and actions. ELC, as earlier noted, has a key role in the practice of sustainable development, ecosystem management, and biodiversity conservation. Spatial scale is a critical variable that must be addressed by ELCs. The effective spatial scale or resolution required for ELCs frequently varies for different management purposes. Modem ELCs are hierarchical and often provide information at two or three different scales, an approach which can satisfy a larger number of potential users. Technological tools like GIS, global positioning systems, remote sensing, and computerized geostatistical and modelling techniques are being used in combination to undertake a wide range of new analyses and interpretations related to ELCs. At a given spatial scale, an ELC framework allows a variety of ecosystem information to be organized; however, testable and well-defined hypotheses must underlie the framework. We should be sceptical of and encouraged to challenge/discuss the placement of lines delineating polygons on maps, and be willing to consider whether the mapped polygons are suitable for our particular purpose(s). Maps may be produced with polygon boundaries formally delineated, but the lines around map polygons must frequently be considered to be "wide and fuzzy" zones. While ELC is fundamental for defining "healthy ecosystems" at various scales, there is now a need to better incorporate a wide range of economic and social considerations, in particular in the form in which they are most applicable at given levels of resolution. Also, types and levels of disturbance impacts need to be more directly considered in ecosystem management, and consequently must be

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more comprehensively dealt with in ELCs. In particular, the inclusion of dynamic forest succession models, pest and insect susceptibility/vulnerability models, fire prediction models, and other "disturbance" models will increase the utility of ELCbased models for land-use planning. ELCs must strive to more directly address management objectives. Forest management requires inventory of the resource in terms of what it is (e.g., via ordered descriptions and quantitatively-based ELCs), where it is (e.g., via conventional mapping and GIS-based approaches), and what can be done to it (e.g., via management prescriptions and legislative controls). The "what can be done" component is perhaps the most problematic of these, in part because it means synthesizing the other components to address a wide variety of resource values. Confusion is frequently created by the myriad of approaches, forums and legislative constraints which serve to assist, address and resolve such conflicts. Inevitably, there are different viewpoints or major conflicts among various stakeholders, including industrial representatives, governments, interest groups and scientists. Forest managers require stand-alone systems (not component inventories) that integrate elements of the forest environment. When evaluating forest site quality, for example, it is now well understood that it must be done within an ecological context; the potential impacts of forest (i.e., timber) management on other aspects of the natural system must be considered in as comprehensive a manner as possible. In order to properly advance the process of land management stewardship, it is also critical to increase the ELC skills and knowledge base of practitioners who are carrying out day-to-day management activities on the ground. Natural ecosystem functions need to be better integrated within ELC frameworks. In future, there will be a growing need to more explicitly link ELCs to those basic factors which support plant and animal life and which serve to integrate ecosystem units. Rapid progress is being made in our scientific understanding of the structure and function of ecosystems. We must use this new ecosystem information effectively (e.g., by means of direct incorporation, systems modelling or the construction of decision support systems) so that more intelligent land-use or ecosystem management decisions can be made. As well, continuing efforts are needed to construct ELC systems which effectively integrate bioecological and geoecological components. In the decades ahead, there will be continuing development of ELCs. New tools and approaches will be created and refined to help land resource managers to better address the objectives of ecosystem management. There are recognized limits to current ELC models and there will be a need to move towards more widelyapplicable and comprehensive "next generation" ELC systems in the future. There will be increasing interest in the development of spatially-related vegetational succession models and predictive tools that evaluate, for example, site-level genetic variability or the susceptibility/vulnerability of forest ecosystems to insect infestations.

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The need for quality, georeferenced ELC-related data will continue to grow. Field-based data derived from properly georeferenced, on-the-ground measurements will continue to be an essential foundation for ELCs, but many other kinds of accurately geocoded data will also be needed. For example, high-resolution satellite and airborne remotely-sensed land-cover data will be increasingly sought after for ELC-related analyses and applications. There will be a particular need for data sources that may be readily updated (e.g., for change-detection purposes) and which have levels of resolution which are compatible with operational levels of forest resource planning. ELC will continue to be "data hungry", and developers and users of ELC systems must continue to gather appropriate information at appropriate scales to help fuel technological advances. Given the increased number of potential users from many disciplines, issues relating to ELC data standards, ownership and data-sharing will become increasingly significant. It will continue to be important to anticipate possible requirements of a whole range of potential users prior to the initiation of data collection for an ELC project.

4. The Current Collection of Articles

The current set of articles, with its emphasis on North American activity (i.e., 37 of 43 articles), is complementary to a recent text which focusses on the status of ELC in Western Europe (Klijn, 1994b). Because of its size and breadth of coverage, the current collection reflects a considerable range of perspectives, activities and emphases, as expressed by a significant number of authors and organizations. Articles are organized according to 11 main headings. Section 1 (Introduction) provides background context. The next four sections (Global Frameworks, Regional Frameworks, Subregional Frameworks, Local Frameworks) include a total of 25 articles oriented across a broad continuum of spatial scales, from a continental level down to a local management level. The two articles in Section 6 (ELC Database Management) deal specifically with the handling and organization of large ELC computerized data-files, while Section 7 (Global to Local Modelling) includes four articles which present some new ELC-based modelling methodologies. Sections 8 and 9 (Soil Moisture Regime and Site Evaluation, Forest Site Quality and Productivity) include a total of six articles which explore relationships of classification systems to site quality, soil moisture and the prediction of stand productivity. The final two sections (ELC-Based Management, ELC-Based Research) include a total of five articles that describe ELC-related applications according to a few specific forest management and research topics.

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References Bailey, R.G., Avers, EE., King, T. and McNab, W.H.: 1994, 'Ecoregions and Subregions of the United States, revised edition', Map at 1:7 500 000 scale, US Dep. Agrie., For. Serv., Washington, DC. Booth, D.L., Boulter, D.W.K., Neave, D.J., Rotherham, A.A. and Welsh, D.A.: 1993, 'Natural forest landscape management: a strategy for Canada', Forestry Chronicle 69, 141-145. Bormann, B.T., Brookes, M.H., Ford, E.D,, Kiester, A.R., Oliver, C.D. and Weigand, J.E: 1994a, 'A framework for sustainable-ecosystem management', Gen. Tech. Rep. No. PNW-GTR-331, US Dep. Agric., For. Serv., Portland, Oregon, 61 pp. Bormann, B.T., Cunningham, P.G., Brookes, M.H., Manning, V.W. and Collopy, M.W.: 1994b, 'Adaptive ecosystem management in the Pacific Northwest', Gen. Tech, Rep. No. PNW-GTR341, US Dep. Agric., For. Serv., Portland, Oregon, 22 pp. Canadian Forest Service: 1995, 'Criteria and indicators for the conservation and sustainable management of temperate and boreal forests: the Montreal Process', Nat. Resour. Can., Hull, Quebec, 27 pp. Crow, T.R.: 1994, 'Habitats, ecosystems, or landscape ecosystem? What's the difference?', In: J.K. Jordan and P.W.C. Uhlig (eds.), Proceedings of the Conference on Ecosystem Management Strategies for the Lake Superior Region, May 16-19, 1994, Continuing Education and Extension, Univ. Minnesota, Duluth, Minn., USA, pp. 12-15. Crow, T.R., Haney, A. and Wailer, D.M.: 1994, 'Report on the scientific roundtable on biological diversity convened by the Chequamegon and Nicolet National Forests', Gen. Tech. Rep. No. NC-166, US Dep. Agric., For. Serv., St. Paul, Minnesota, 54 pp. Francis, G.: 1993, 'Ecosystem management', Natural Resources Journal 33, 315-345. Grumbine, R.E.: 1994, 'What is ecosystem management?', Conserv. Biol. 8, 27-38. Holling, C.S. (ed.): 1978, Adaptive Environmental Assessment and Management, John Wiley and Sons, Inc., New York, USA, 377 pp. Jordan, J.K. and Uhlig, P.W.C. (eds.): 1994, Proceedings of the Conference on Ecosystem Management Strategies for the Lake Superior Region, May 16-19, 1994, Continuing Education and Extension, Univ. Minnesota, Duluth, Minn., USA, 69 pp. Kaufmann, M.R., Graham, R,T., Boyce, D.A., Moir, W.H., Perry, L., Reynolds, R.T., Bassett, R.L., Mehlop, P., Edminster, C.B., Block, W.M. and Corn, P.S.: 1994, 'An ecological basis for ecosystem management', Gen. Tech. Rep. No. RM-246, US Dep. Agric., For. Serv., Ft. Collins, Colorado, 22 pp. Kimmins, J.P.: 1987, Forest Ecology, Macmillan Publ. Co., New York, USA, 531 pp. King, A.W.: 1993, 'Considerations of scale and hierarchy', In: S. Woodley, J. Kay and G. Francis (eds.), Ecological Integrity and the Management of Ecosystems, Heritage Res. Centre, Univ. Waterloo, Waterloo, Ont. and Can. Parks Serv., Ottawa, Ont., pp. 19-45. Klijn, F.: 1994a, 'Spatially nested ecosystems: guidelines for classification from a hierarchical perspective', In: E Klijn (ed.), Ecosystem Classification for Environmental Management, Kluwer Academic Publishers, Dordrecht, The Netherlands, pp. 85-116. Klijn, E (ed.): 1994b, Ecosystem Classification for Environmental Management, Kluwer Academic Publishers, Dordrecht, The Netherlands, 293 pp. Larsen, G.L.: 1994, 'Forests at UNCED: an emerging global consensus toward sustainability', In: M.H. Huff, L.K. Norris, J.B. Nyberg and N,L. Wilkin (coords.), Expanding Horizons of Forest Ecosystem Management: Proceedings of Third Habitat Futures Workshop, October 1992, Vernon, British Columbia, Gen. Tech. Rep. No. PNW-GTR-336, US Dep. Agile., For. Serv., Portland, Oregon, pp. 1-15. Larsen, J.B.: 1995, 'Ecological stability of forests and sustainable silviculture', Forest Ecol. and Manage. 73, 85-96. Mann, C.C. and Plummer, M.L.: 1993, 'The high cost of biodiversity', Science 260, 1868-1871. Marshall, I.B. and Smith, C.A.S.: 1996, 'A national ecosystems framework for monitoring and reporting on environmental sustainability in Canada', Envir. Monitor. andAssessm. (this volume). McKenney, D.W., Sims, R.A., Soul6, M., Mackey, B.G. and Cambell, K.L. (eds.): 1994, Towards a Set of Biodiversity Indicators for Canadian Forests: Proceedings of a Forest Biodiversity Indicators Workshop, Can. Forest Serv., Sault Ste. Marie, Ont., 133 pp.

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McKenney, D.W., Sims, R.A. and Mackey, B.G.: 1996, 'Primary databases for forest ecosystem management - examples from Ontario and possibilities for Canada: NatGRID', Envir. Monitor. andAssessm. (this volume). McNab, W.H. and Avers, P.E. (compilers): 1994, 'Ecological Subregions of the United States: Section Descriptions', Admin. Publ. No. WO-WSA-5, US Dep. Agric., For. Serv., Washington, DC, 267 pp. Rowe, J.S.: 1961, 'The level of integration concept and ecology', Ecology 42, 420-427. Rowe, J.S.: 1992, 'The ecosystem approach to forestland management', Forestry Chronicle 68, 222-224. Rowe, J.S.: 1996, 'Land classification and ecosystem classification', Envir. Monitor. and Assessm. (this volume). Rowe, J.S. and Sheard, J.W.: 1981, 'Ecological land classification: a survey approach', Environmental Management 5(5), 451-464. Salwasser, H. and Pfister, R.D.: 1994, 'Ecosystem management: from theory to practice', In: W.W. Covington and L.E DeBano (tech. coords.), Sustainable Ecological Systems: Implementing an Ecological Approach to Land Management, Gen. Tech. Rep. No. RM-247, US Dep. Agric., For. Serv., Ft. Collins, Colo., pp. 150-161. Simberloff, D.: 1994, 'How forest fragmentation hurts species and what to do about it', In: W.W. Covington and L.E DeBano (tech. coords.), Sustainable Ecological Systems: Implementing an Ecological Approach to Land Management, Gen. Tech. Rep. No. RM-247, US Dep. Agric., For. Serv., Ft. Collins, Colo., pp. 85-90. Slocombe, D.S.: 1993, 'Implementing ecosystem-based management', BioScience 43, 612--622. Swanson, EJ. and Franklin, J.E: 1992, 'New forestry principles from ecosystem analysis of Pacific Northwest forests', Ecol. Applic. 2, 262-274. Tansley, A.G.: 1935, 'The use and abuse of vegetational concepts and terms', Ecology 16, 284-307. Udo de Haes, H.A. and Klijn, E: 1994, 'Environmental policy and ecosystem classification', In: E Klijn (ed.), Ecosystem Classification for Environmental Management, Kluwer Academic Publishers, Dordrecht, The Netherlands, pp. 1-22. Urban, D.L.: 1994, 'Landscape ecology and ecosystem management', In: W.W. Covington and L.E DeBano (tech. coords.), Sustainable Ecological Systems: Implementing an Ecological Approach to Land Management, Gen. Tech. Rep. No. RM-247, US Dep. Agric., For. Serv., Ft. Collins, Colo., pp. 127-136. Urban, D.L., O Neill, R.V. and Shugart, H.H.: 1987, 'Landscape ecology - a hierarchical perspective can help scientists understand spatial patterns', BioScience 37, 119-127. Walters, C.J. and Holling, C.S.: 1990, 'Large scale management experiments and learning by doing', Ecology 71, 2060-2068. Wiken, E.B., Welch, D.M., Ironside, G.R. and Taylor, D.G.: 1981, 'The northern Yukon: an ecological land survey', Ecological Land Classification Series No. 6, Environment Canada, Vancouver, British Columbia, 197 pp. (with map at 1:1 000 000 scale). Wiken, E.B., Rubec, C.D.A. and Ironside, G.: 1993, 'Canada s Terrestrial Ecoregions, 5th ed.', (MCR 4164), Map at 1:7 500 000 scale, National Atlas of Canada, Canada Centre for Mapping, Energy, Mines and Resources, and State of the Environment Reporting, Environment Canada, Ottawa, Ontario. Zonneveld, I.S.: 1994, 'Basic principles of classification', In: E Klijn (ed.), Ecosystem Classification for Environmental Management, Kluwer Academic Publishers, Dordrecht, The Netherlands, pp. 23-47.

Introduction-global to local: Ecological Land Classification.

Ecological Land Classification (ELC) is a scientific endeavour which attempts to organize, stratify and evaluate ecosystems (and complexes of ecosyste...
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