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1996 | Buch

Global to Local: Ecological Land Classification

Thunderbay, Ontario, Canada, August 14–17, 1994

herausgegeben von: Richard A. Sims, Ian G. W. Corns, Karel Klinka

Verlag: Springer Netherlands

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Über dieses Buch

Ecological Land Classification (ELC) refers to the description of land resources at a range of spatial resolutions (i.e. global to local) and for a range of purposes or values. The emerging science of ELC is in fact a very carefully integrated blend of vegetation and earth sciences, climatology, cartography and ecology with a range of new technologies and methodologies including computer-based geographic information systems, remote sensing and simulation modelling.
This publication defines the current `state-of-the-art' of ELC. It provides particular insight into the role of ELC in current and future forest resource planning and management, and emphasizes its application and usefulness at various spatial scales, for a variety of geographic locations, and under a range of management scenarios/constraints. The book is an invaluable and substantial reference source about the current trends in ELC and will be of particular value to ecologists, foresters, geographers, resource managers, wildlife biologists, GIS and remote sensing specialists, educators and students.

Inhaltsverzeichnis

Frontmatter

Introduction

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 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.

Richard A. Sims, Ian G. W. Corns, Karel Klinka
Land Classification and Ecosystem Classification

Earth, the ecosphere, is a unified functional ecosystem. Ecological land classification (ELC) and regionalization divides and categorizes this unity into similar and dissimilar pieces — sectoral ecosystems — at various scales, in the interests of admiration and understanding. The recognition of land/water ecosystems in a hierarchy of sizes provides a rational base for the many-scaled problems of protection and careful exploitation in the fields of agriculture, forestry, wildlife and recreation. In forested terrain the protection of biodiversity, old growth forests, watersheds and wildlife habitat depends on spatial-temporal planning of forestry operations to maintain a preferred mosaic structure of local ecosystems within each ecological region. Without ecological understanding and a good ELC, this is impossible. Conceiving the world as comprising nested land/water ecosystems that are the source of life, elevates the role of Earth-as-context, an antidote to destructive anthropocentrism.

J. Stan Rowe

Global Frameworks

Multi-Scale Ecosystem Analysis

As a precursor to management, ecosystems of different sizes need to be mapped at different scales. The key to developing criteria for subdividing land into ecosystems is understanding the factors that control ecosystem size at various scales in a hierarchy. The relationships between an ecosystem at one scale and ecosystems at smaller or larger scales must be examined, in order to predict the effects of management. Multi-scale mapping is helpful in analyzing relationships of this type.

Robert G. Bailey
A National Framework for Monitoring and Reporting on Environmental Sustainability in Canada

In 1991, a collaborative project to revise the terrestrial component of a national ecological framework was undertaken with a wide range of stakeholders. This spatial framework consists of multiple, nested levels of ecological generalization with linkages to existing federal and provincial scientific databases. The broadest level of generalization is the ecozone. Macroclimate, major vegetation types and subcontinental scale physiographic formations constitute the definitive components of these major ecosystems. Ecozones are subdivided into approximately 200 ecoregions which are based on properties like regional physiography, surficial geology, climate, vegetation, soil, water and fauna. The ecozone and ecoregion levels of the framework have been depicted on a national map coverage at 1:7 500 000 scale. Ecoregions have been subdivided into ecodistricts based primarily on landform, parent material, topography, soils, waterbodies and vegetation at a scale (1:2 000 000) useful for environmental resource management, monitoring and modelling activities. Nested within the ecodistricts are the polygons that make up the Soil Landscapes of Canada series of 1:1 000 000 scale soil maps. The framework is supported by an ARC-INFO GIS at Agriculture Canada. The data model allows linkage to associated databases on climate, land use and socio-economic attributes.

Ian B. Marshall, C. A. Scott Smith, Corrine J. Selby
The ITE Land Classification: Providing an Environmental Stratification of Great Britain

The surface of Great Britain (GB) varies continuously in land cover from one area to another. The objective of any environmentally based land classification is to produce classes that match the patterns that are present by helping to define clear boundaries. The more appropriate the analysis and data used, the better the classes will fit the natural patterns. The observation of inter-correlations between ecological factors is the basis for interpreting ecological patterns in the field, and the Institute of Terrestrial Ecology (ITE) Land Classification formalises such subjective ideas. The data inevitably comprise a large number of factors in order to describe the environment adequately. Single factors, such as altitude, would only be useful on a national basis if they were the only dominant causative agent of ecological variation.The ITE Land Classification has defined 32 environmental categories called ‘land classes’, initially based on a sample of 1-km squares in Great Britain but subsequently extended to all 240 000 1-km squares. The original classification was produced using multivariate analysis of 75 environmental variables. The extension to all squares in GB was performed using a combination of logistic discrimination and discriminant functions. The classes have provided a stratification for successive ecological surveys, the results of which have characterised the classes in terms of botanical, zoological and landscape features.The classification has also been applied to integrate diverse datasets including satellite imagery, soils and socio-economic information. A variety of models have used the structure of the classification, for example to show potential land use change under different economic conditions. The principal data sets relevant for planning purposes have been incorporated into a user-friendly computer package, called the ‘Countryside Information System’.

R. G. H. Bunce, C. J. Barr, M. K. Gillespie, D. C. Howard
Spatial Scale-Dependent Policy Planning for Land Management in Southern Europe

This study outlines an original tool for rural policy planning in southern Europe. This new tool is a process-based, scale-dependent, rural policy-making approach, which is designed to address increasing land degradation problems in southern Europe. Seven important processes are identified (land abandonment, devegetation, intensification in agriculture, global climate change, accelerated soil erosion, increasing water demands, urbanisation) and plotted on a space-time diagram, which clearly shows the spatial and temporal scales for which these processes are significant for landscape change in southern Europe. Conclusions are derived concerning, in particular, sustainable (optimal) rural policy-making for southern Europe’s problematic land management. An optimal spatial-temporal scale for land management in southern Europe may range spatially from the “farm” (0.5 km2) to “sub-provincial” level (450 km2) and temporally from 7 to 30 years. The study delineates methods and results derivable from such a new policy-planning approach and suggests the usefulness of combining this approach with ecological land classification at the landscape level.

Fivos Papadimitriou, Paola Mairota

Regional Frameworks

A Spatial Hierarchical Framework for the Co-Management of Ecosystems in Canada and the United States for the Upper Great Lakes Region

Over the past three decades, considerable effort has been invested in the development of complex and comprehensive ecosystem classifications and inventories in many parts of North America. Paralleling this has been an evolution in those hierarchical frameworks guiding the development and application of classifications. However, resource management agencies continue to grapple with the dilemma of applying multiple classification and inventory templates over large jurisdictions, especially as they attempt to address ecosystem management objectives. Given that Canada and the United States share ecosystems and that commitments have been made by all levels of government to make progress towards ecosystem-based approaches to management, there is a need to provide the proper tools. Comprehensive goals will not be achieved without collaboration and cooperation.This paper outlines the range of ecosystem classification approaches that exist in the Upper Great Lakes region. Canadian and American national hierarchical frameworks are briefly examined. Specific information needs and tasks are outlined which must be followed, independent of national boundaries, for the successful integration of planning and monitoring programs for large regional ecosystems.A general model is proposed for the development and application of an integrated, multi-scale and bi-national ecosystem classification, inventory and information system. This approach would facilitate data sharing and communication across jurisdictional boundaries.

Peter W. C. Uhlig, James K. Jordan
Development of a Multilevel Ecological Classification System for the State of Minnesota

The Minnesota Department of Natural Resources (MNDNR) began development of an Ecological Classification System (ECS) in 1991. The ECS is hierarchically organized into six levels following the United States Forest Service structure. The upper four levels are being developed State-wide by an interdisciplinary group from several agencies. Geographic Information Systems approaches are being used to overlay and integrate existing data. The first two levels (Province and Section) have been completed. The third level (Subsection) is nearly completed, and work on the fourth level (Land Type Association (LTA)) started in January 1995. Classification and inventory for the lowest two levels (Ecological Land Type and Ecological Land Type Phase) was cooperatively undertaken on two Land Type Associations within the Chippewa National Forest. A sample set of management interpretations is being developed and tested for the two lower levels. Workshops demonstrating how ECS can be used for natural resource management began in mid-1995 and will continue for several years, as will development of the lower two levels on LTAs beyond the Chippewa National Forest.

Dan S. Hanson, Bryan Hargrave
A Strategic Framework to Eco-Regionalize Ontario

Ontario is a spatially heterogenous province. Natural resource policies and management plans must therefore address and account for this heterogeneity.An eco-regionalization scheme must possess certain minimum criteria to be effective. These criteria are: 1) an explicit explanation of spatial and temporal scales and variation; 2) a hierarchical construct of eco-regional domains; 3) an explicit quantitative description of the eco-regional domains; and, most importantly, 4) an ability to test a given eco-regional scheme as a hypothesis.This paper describes a hierarchical eco-regional framework (HEF) currently being constructed for Ontario. HEF is based on the scale-specific expression of ecological domain structure (geo-climatological parameters) and function (primary productivity). The approach relies on current advances in ecological hierarchy theory, remote sensing techniques, GIS methodologies, and statistical techniques. When completed, HEF will serve as a hypothesis which may be tested and validated at several different spatial scales.

Ajith H. Perera, James A. Baker, Lawrence E. Band, David J. B. Baldwin
Ecosystem Mapping Methods for British Columbia

Most resource professionals in British Columbia recognize the value of ecosystem classification in providing a conceptual framework and common language for organizing ecological information and management experience about ecosystems.Ecosystem mapping utilizes principles of ecosystem classification in order to provide a permanent record of the location and distribution of ecosystems. This spatial framework is often required for developing, applying, and monitoring landscape level and site-specific management prescriptions for many potential resource values.Over the past 20 years, several approaches to ecosystem mapping have been applied throughout the province. Standard procedures for provincial resource inventories and standards for medium and large scale ecosystem mapping (1:10 000 to 1:100 000 scales) have recently been proposed for the province. The proposed mapping approach combines elements of two classification systems currently in use in the province: ecoregion classification and biogeoclimatic ecosystem classification (BEC). Ecoregion and biogeoclimatic units stratify the landscape into broad physiographically and climatically uniform units. Within this broad framework, permanent landscape units are then delineated based on terrain features. Ecosystem units represent the lowest-level mapping individuals and are derived from the site series classification within BEC. Ecosystem units thus reflect moisture and nutrient regime and the climax vegetation potential of the site. Additional site modifiers are included to recognize variation in topography and soils within the site series. Structural stage and seral association modifiers are included to describe existing vegetation characteristics.The mapping methods present a core list of attributes required for basic resource interpretations, as well as additional attributes required for more specific interpretations.

A. Banner, D. V. Meidinger, E. C. Lea, R. E. Maxwell, B. C. Von Sacken
An Ecological Framework for Resource Management in British Columbia

British Columbia’s landmass encompasses a complex diversity of ecosystems as a result of its diverse physiography, geology and climate. Resource planners and managers, depending upon their management objectives, use ecological information at different scales, from the very broad regional level to the local or site-specific level. The Ecoregion Classification and the Biogeoclimatic Ecosystem Classification systems provide the means for resource managers and others in British Columbia concerned with the environment to understand, manage, and communicate about the diverse ecosystems of the province.This paper outlines this multi-level regional ecological classification and describes how it is being applied by resource managers from various resource agencies and organizations responsible for forest, wildlife and habitat management in British Columbia.

S. Mah, S. Thomson, D. Demarchi
Land District, Ecophysiographic Units and Areas: The Landscape Mapping of the Ministère Des Ressources Naturelles Du Québec

In 1985, the Ministère des Ressources naturelles established a Forest Ecological Survey Program for Southern Québec. One component of the program was the mapping of land districts, which provide a physiographically-based territorial reference system. The land districts have an average surface area of between 100 and 300 sq km. Since its inception, the department has further refined the methodologies and standardized the results. The current methodologies are based on inventory and analysis of the geographical distribution of permanent environmental components (e.g., relief, surficial deposits, geology, hydrography). The products include 1:50 000 maps of surficial deposits, 1:250 000 maps of the land districts and physiographic systems, and a computerized data bank.To date, 500 000 km square have been covered, and the estimated completion date for the work is 1999. To facilitate use of the products and to encourage the development of new applications, a guide for forest managers and other users has been recently published. The guide assists with forest management planning strategies based upon the physical environment, in particular the production and use of interpretation grids and maps. The products of the mapping process are, for many regions of Southern Québec, the only source of information on permanent environmental components.Currently, the Ministère des Ressources naturelles is planning to develop landscape maps of Southern Québec which identify ecophysiographic units (1:1 250 000) and ecophysiographic areas (1:2 500 000). These maps are based upon the integration of critical physiographic features and the synthesis of land regions.

André Robitaille, Jean-Pierre Saucier

Subregional Frameworks

Developing an Ecological Land Classification for the Fundy Model Forest, Southeastern New Brunswick, Canada

The methodology for developing and mapping a hierarchical Ecological Land Classification (ELC) is presented. The classification provided a systematic methodology that explained the distribution and composition of southern New Brunswick’s forested landscape. The nested structure of the ELC identified and provided a hierarchical linkage between ecosystems from the size of forest stands to climate regions. This framework made the collection and analysis of data efficient and gave confidence that tree species distributions, which were central to understanding the influence of abiotic factors on the forest systems, were controlled by the factors examined at each level of the hierarchy. This ELC methodology, developed for the Fundy Model Forest, was successful in describing and mapping the Climate, Geomorphologic, and Regolith controlled forest ecosystems. Preliminary classification indicates that spatial referencing of the Site Level is achievable.

Bruce E. Matson, Randal G. Power
Ecological Mapping: A Framework for Delimiting Forest Management Units

Ecological mapping attempts to objectively and spatially delimit and represent the natural organization and structure of the landscape. It offers nested levels of resolution, based upon a regionalization process, and provides an ecological basis for planning activities that may impact upon the environment.The essential principles of ecological mapping, as applied by the Quebec Ministry of Environment and Wildlife, are summarized. A methodological mapping approach is proposed for the determination of significant land portions for forest management using an ecological map at a scale of 1:50 000. At this scale, two nested levels of perception are expressed: 1) the topographic complex, and 2) the topographic entity. The topographic entity can be further subdivided into working units based upon operational criteria oriented to forest management. Within each nested level from topographic complex to working unit, there is a corresponding increase in the amount of detailed information available. Ecological mapping undertaken at 1:50 000 scale can provide a reliable and robust tool for planning forest management activities. In most cases, major ecological variations can be expressed and mapped at this scale; however, a greater degree of generalization must be accepted in the planning process when working at this scale rather than at larger scales.

Patrick Beauchesne, Jean-Pierre Ducruc, Vincent Gerardin
Application of the USDA Forest Service National Hierarchical Framework of Ecological Units at the Sub-Regional Level: The New England-New York Example

Ecological regionalization according to the USDA Forest Service National Hierarchical Framework of Ecological Units was undertaken for the New England-New York region. A top-down, map-overlay approach was used to map sections and subsections. Where available, landscape level units (LTAs) were aggregated and evaluated to supplement the subsection mapping. A regional collaborative effort was undertaken to counterbalance the shortfalls of a purely mechanistic approach. As a result of this process, 17 section and 58 draft subsection units were delineated for the New England-New York region. The sub-regional units developed reflect the strong correspondence among climate, topography and geography at this scale. Geologic factors, due to their influence on landform and mineral availability, are also reflected in the ecological unit boundaries. Efforts to apply the multifactor model at the sub-regional level have been hampered by the lack of scale appropriate information on a number of factors particularly meso-scale climate and potential natural community composition and distribution. Further research and investigation are required before these criterion are adequately met.

Marie-Louise Smith, Constance Carpenter
Development of Ecological Land Classification and Mapping in Support of Forest Management in Northern Newfoundland, Canada

For the sustainable development of forest land, as recently prescribed by the Canadian Forest Strategy, a land classification project in northern Newfoundland was initiated to support the local forest management activities. The method adopted here is a modification of the Canadian Committee for Ecological Land Classification’s (CCELC) system, and it applies various levels of mapping to uniform areas based on geomorphology, soils, vegetation, climate, water, and fauna.In this study, all CCELC levels were mapped; resulting maps were digitized and imported into a Geographic Informations System (GIS). The GIS data base contained the following maps: 1) digital terrain model, 2) bedrock geology, 3) surficial geology, 4) forest inventory, and 5) various levels of the ecological land classification, including Vegetation Types at the lowest level. In addition to the mapping, mensurational data were analyzed to provide stand and stock tables for each of the forest types, including growth curves that could be entered into specific forest growth modelling systems to predict wood supply scenarios based upon different management interventions.

Denes Bajzak, B. A. Roberts
Classification of Local- and Landscape-Scale Ecological Types in the Southern Appalachian Mountains

Five local ecological types based on vegetative communities and two landscape types based on groups of communities, were identified by integrating landform, soil, and vegetation components using multivariate techniques. Elevation and several topographic and soil variables were highly correlated with types of both scales. Landscape ecological types based only on landform and soil variables without vegetation did not correspond with types developed using vegetation. Models developed from these relationships could allow classification and mapping of extensive areas using geographic information systems.

W. Henry McNab

Local Frameworks

Development of a Practical Forest Ecosystem Classification from Existing Biophysical Studies: An Approach Used in Northwestern Quebec

While forest ecosystem classification work in Quebec has traditionally concentrated on inventory and mapping, more effort is now being placed on developing field guides similar to those produced in other Canadian provinces. As part of a project to produce a practical forest ecosystem field guide for the Amos Lowlands Ecological Region in northwestern Quebec, existing sub-regional ecological studies were exploited in order to develop a regional classification of forest ecosystems, or forest stations. Review of four fundamental studies provided a list of 107 ecological phases, each representing a particular combination of forest composition, surface deposit type and moisture regime. A series of silvicultural and environmental interpretations were developed and values for each were attributed to the ecological phases. Cluster analysis was then performed to classify phases into 29 broader units. A large, regional biophysical database which became available later in the project provided a means of validating and effectively modifying the classification. The justifications for using the original approach are discussed.

Brian D. Harvey, Pierre Cartier, Yves Bergeron, Philippe Nolet
A Forest Ecosystem Guide for the Amos Lowlands Ecological Region, Northwestern Quebec: A Forest Management Approach

In Quebec, forest stations are defined as forest units that are reasonably homogeneous in terms of forest composition and site characteristics — as expressed by surficial deposit and moisture regime — and within which similar operational constraints for silvicultural potential and productivity levels may be expected. In the course of developing a field guide to the forest stations of the Amos Lowlands Ecological Region in northwestern Quebec, classifications of 12 site types and 72 forest stations (38 forest cover types or 16 general cover types) were developed. The classifications were based on a hybrid approach involving cluster analysis of forest ecological units inventoried in sub-regional studies, classical classification and ordination analyses performed on a regional biophysical inventory database, and empirically associating forest cover types to site types. The guide, while similar to other published forest ecosystem classification guides, emphasizes forest dynamics by presenting forest stations common to a given site type according to their successional stage. Field keys and general interpretations of forest potential and operational constraints are included in the guide. A summary description of the guide and accompanying documents is provided. A first draft has been distributed recently for feedback from industrial and government foresters and researchers in the region. Analyses of inventory data is continuing and modifications will be incorporated into a second draft before publication in 1995.

Pierre Cartier, Brian D. Harvey, Yves Bergeron
Ecosystem Types of Boreal Forest in the North Klondike River Valley, Yukon Territory, Canada, and Their Productivity Potentials

Vegetation, environmental characteristics, and forest productivity were studied in the boreal forest in the North Klondike River Valley, Yukon Territory, Canada. The concept and approach of biogeoclimatic ecosystem classification were followed. For the treed vegetation, five ecosystem types were distinguished based on vegetation structure and physical and chemical properties of soils. They were: 1) spruce-lichen type, 2) spruce-moss type, 3) spruce-Equisetum type, 4) spruce-willow type, and 5) bog forest type. These types were differentiated mainly by moisture regime and base status of soils. The sequence of the ecosystem types reflected their topographical position from slope summit to valley bottom. The spruce-lichen type developed in the driest and nutritionally impoverished habitats, the spruce-Equisetum type occurred in moist and nutritionally enriched sites, and the spruce-moss type was found in between them. The bog forest type occurred where peat had accumulated sufficiently to generate ombrotrophic conditions in habitats of high water table underlain with permafrost. The spruce-willow type developed along small creeks where substrates were very coarse. Tree growth characteristics were measured, except for the bog forest type that did not have trees over 5 m tall. Total volume of standing trees ranged from 29 to 582 m3/ha, with an overall mean of 216.9 m3/ha. The spruce-Equisetum type exhibited the highest figure, 413.5 m3/ha, while the spruce — lichen type the lowest one, 87.7 m3/ha. Mean annual increment ranged from 0.15 to 2.66 m3/ha, with an overall mean of 1.10 m3/ha. A similar tendency was noted for all other forestry characteristics, i.e., the spruce-Equisetum type showed the highest productivity while the spruce-lichen type the lowest. This tendency was considered to be attributed to the availability of moisture and basic cations in soils.

S. Kojima
Impacts of Logging and Wildfire on an Upland Black Spruce Community in Northwestern Ontario

Plant species composition and community structure were compared among four sites in an upland black spruce community in northwestern Ontario. One site had remained undisturbed since the 1930s and three had been disturbed by either logging, fire, or both logging and fire. Canonical correspondence ordination analyses indicated that herbaceous species composition and abundance differed among the disturbance types while differences in the shrub and tree strata were less pronounced. In the herb stratum Pleurozium schreberi, Ptilium crista-castrensis and Dicranurn polysetum were in greatest abundance on the undisturbed forest site, while the wildfire and burned cutover sites were dominated by Epilobium angustifolium and Polytrichum juniperinum. The unburned harvested site was dominated by Epilobium angustifolium, Cornus canadensis and Pleurozium schreberi. Species richness was lower on the undisturbed site than on any of the disturbed sites while species diversity (H’) and evenness (Hill’s E5) were higher on the unburned harvested site than on the other sites. Results suggest that herb re-establishment is different among harvested and burned sites in upland black spruce communities and we hypothesize that differences in the characteristics of the disturbance were responsible, in particular, the impact of burning on nutrient availability. These differences need to be taken into account in determining the effects of these disturbances on biodiversity and long-term ecosystem management.

M. H. Johnston, J. A. Elliott
A Community Classification System for Forest Evaluation: Development, Validation, and Extrapolation

A community classification system integrating vegetation and landforms was developed for the 8,054-ha Cheatham Wildlife Management Area (CWMA), located on the Western Highland Rim of Tennessee, USA, to obtain information on which to base multiresource land management decisions. A subjective procedure (synthesis tables) and several objective techniques (factor analysis, cluster analysis, and canonical discrimination) were used to evaluate importance values of overstory and midstory species, coverage values of understory species, and topographic parameters. These procedures were used collectively to guide and to provide evidence for interpretation of vegetational patterns on the landscape. The eight discrete communities identified on a 482-ha compartment within the CWMA were: northern red oak (Quercus rubra L.), chestnut oak (Q. prinus L.), scarlet oak (Q. coccinea Muenchh.), yellow-poplar (Liriodendron tulipifera L.), sycamore-sweetgum (Platanus occidentalis L. — Liquidambar styraciflua L.), black oak-hickory (Q. velutina Lam. — Carya spp.), post oak (Q. stellata Wangenh.), and American beech (Fagus grandifolia Ehrh.) communities. The classification system was validated with an independent data set. The eight communities were successfully extrapolated to an unsampled portion of the CWMA. Clearly, community analysis can become an important facet in forest management and may play a major role where a holistic understanding of vegetative relationships is essential.

Wayne K. Clatterbuck
Landscape Ecosystem Classification in the Cherokee National Forest, East Tennessee, U.S.A.

A landscape ecosystem classification is described for the 43 800 ha Foothills section (elevation 305 to 610 m) of the southern unit of the Cherokee National Forest. Vegetative cover, landform, and soils data were obtained from sixty 0.04 ha plots located in stands representing late successional stages. Vegetation data were grouped by dominant cover type utilizing agglomerative, hierarchical clustering and detrended correspondence analysis. Detrended canonical correspondence analysis (DCCA) and stepwise discriminant analysis (SDA) were used to identify patterns in species composition explained by environmental variables.Four community types were identified: (1) Tsuga canadensis — Acer saccharum — Fagus grandi-folia — Fraxinus americana, (2) Tsuga canadensis — Rhododendron maximum, (3) Quercus prinus, and (4) Quercus prinus — Quercus coccinea — Acer rubrum. A recently developed “Landform Index” that quantifies slope type and degree of protection by adjacent land masses was identified through DCCA and SDA as the most important predictor of community types. The strength of the correlations between elevation and several soil thickness variables with DCCA axis 1 indicated that vegetation varies along an interpreted moisture gradient. No ecological meaning was attributed to the second axis.

Kathleen A. Yoke, John C. Rennie
Landtype-Forest Community Relationships: A Case Study on the Mid-Cumberland Plateau

Relationships between forest communities and landtypes (the most detailed level of a hierarchical land classification system) were determined for the Prentice Cooper State Forest (PCSF), located on the southern tip of Waiden Ridge, west of Chattanooga, Tennessee.Four extensive landtypes within the Mullins Cove area of PCSF were sampled: 1) broad sandstone ridges — south aspect (LT-3), 2) north sandstone slopes (LT-5), 3) south sandstone slopes (LT-6), and 4) plateau escarpment and upper sandstone slopes and benches — south aspect (LT-17). Rectangular, 0.04-hectare plots specified sub-plots for sampling overstory, midstory, sapling/shrub, seedling/herb forest strata, and physical site characteristics. Plots (139) were allocated by landtype using a random start with subsequent systematic location.Multivariate statistical techniques were used to 1) examine the distinctness of forest communities occurring among landtypes (discriminant analysis), 2) describe the forest communities occurring within landtypes (cluster analysis), and 3) determine factors controlling the spatial distribution of forest communities on the landscape (factor analysis).Different relative importance values of species among communities along with different community combinations among landtypes resulted in distinct forest vegetation among landtypes.Chestnut oak (Quercus prinus L.), white oak (Quercus alba L.), and shortleaf pine (Pinus echinata Miller) communities occurred on all four landtypes. Scarlet oak (Quercus coccinia Muenchh.) communities occurred on LT-5, LT-6, and LT-17. Black oak (Quercus velutina Lam.) communities occurred on LT-3 and LT-5. Yellow-poplar (Liriodendron tulipifera L.), northern red oak (Quercus rubra L.), and eastern hemlock (Tsuga canadensis (L.) Carr.), communities occurred only on LT-17.Landscape scale factors that varied along an elevation gradient were dominant in controlling spatial distribution of forest communities. Microsite factors were secondary controllers. Specific ecological factors could not be determined by factor analysis.Relatively distinct vegetation occurs among sampled landtypes on the PCSF. This study provides additional evidence that the land classification system divides the Mid-Cumberland Plateau landscape into distinct ecological units.

David H. Arnold, Glendon W. Smalley, Edward R. Buckner
A Cooperative, Integrated Project to Classify Forest Sites in Newfoundland

Most existing systems of forest site classification attempt to combine vegetation, soil, terrain, geology, climatic and hydrologic factors. The current paper describes an ongoing project to assess the relationship of these factors to forest site capability in Newfoundland. Through the description and classification of forest inventory plots, this project is providing productivity data for species, descriptions of vegetational succession, growth and yield projections, as well as an indication of soil type variation within Forest Management Districts.The cooperative, multi-agency approach employed in this project has benefited all parties concerned, and has resulted in a mix of expertise and focus of resources that would not be possible within one agency. A large and valuable bank of vegetation, soil and site data is being acquired. Elements of the project include: 1) establishment of permanent forest inventory sample plots, in Management Districts throughout the province; 2) training of forest inventory crews so that they recognize forest vegetation, accurately prepare soil descriptions and undertake soil sampling; 3) laboratory analyses of soil samples for chemical and physical parameters, and integration of these results into the forest site classification; and, 4) formal reporting of the forest site classification, including improved descriptions of Damman Forest Site Types (FSTs) and soils.

B. A. Roberts, E. F. Woodrow, Denes Bajzak, S. M. Osmond

Database Management

The Development of an Ecological Classification Data Management and Analysis System for British Columbia

Since 1975, the British Columbia Ministry of Forests has been systematically developing an ecosystem classification of the province, an area covering 94 million hectares. This Biogeoclimatic Ecosystem Classification (BEC) system provides a framework for resource conservation and management. To date, approximately 250 person-years have been invested in the collection, analysis and synthesis of over 8000 ecological (vegetation and environmental data) plots, and in the production of ecological field guides.The development of a database and analysis system on the micro-computer platform to support a classification system of this magnitude was a complex procedure that required judicious planning and coordination. We have developed data-processing software that permits a user to select raw data from broad provincial or regional coverage to plot- and species-level summaries, and to export the data to a variety of output formats.This paper addresses key issues for handling ecological field data on the desktop computer with emphasis on standards, operator ease-of-use, and data access.

G. M. Britton, D. V. Meidinger, A. Banner
The Countryside Information System: A Strategic-Level Decision Support System

The Institute of Terrestrial Ecology (ITE) has monitored ecological change in Great Britain (GB) since 1978. The task has been undertaken using a stratified sampling scheme working with a 1 km square as the sample unit. In more recent years, scientific researchers at ITE have been working closely with the policy-makers of the United Kingdom Department of the Environment. The presentation of information to policy advisors and planners was a component within a large project investigating the ecological consequences of land-use change. A simple PC-based decision support system was developed during the project and subsequently has been expanded to produce a marketable product. The system, called the Countryside Information System (CIS), presents and links information at national, regional and thematic levels along with qualifying data describing accuracy and appropriateness of use (i.e., metadata). An integral part of the CIS is the ITE Land Classification, which divides GB into 32 environmental land classes; all 250 000 squares have been classified. The classification allows sampled data to be presented and, as the co-ordinate system is widely used in GB, it allows census datasets to be linked and compared. CIS has been described as a Geographical Information System, but the classification, data held within the system, and the use of metadata to assist in interpretation of results make the system much more decision-support oriented. Indeed, government departments have been involved in directing the development and are now starting to use the system to answer parliamentary questions and formulate, assess and monitor environmental policy. The CIS is an open system, running on a standard PC in Microsoft Windows. Tools for loading and editing new datasets (both sample and census) are incorporated in the suite of programs. The Windows environment and users comments during development have produced a system with an intuitive feel, removing some of the overhead of acquiring specialised technical skills before being able to operate a system. This paper describes the CIS and presents examples of its applications.

David C. Howard, R. G. H. Bunce

Global to Local Modelling

Linking Satellite and Field Survey Data, Through the Use of GIS, as Implemented in Great Britain in the Countryside Survey 1990 Project

The Institute of Terrestrial Ecology (ITE) has been studying land use and the effects of land use on ecology for two decades. A series of national field surveys have been undertaken by the Land Use Section of ITE since 1978, the most recent being Countryside Survey 1990 (CS1990). The three-year project brought together field survey and remote sensing data which were analyzed using Geographical Information Systems (GIS). National and regional land-cover patterns were described and changes estimated.The data collected by the field survey part of CS1990 recorded stratified samples based on a land classification. Thematic maps for surveyed 1-km squares covered physiography, agriculture and semi-natural vegetation, forestry, structures and boundaries. The same sites were surveyed in 1984 and 1990 with 14 000 digital maps produced describing both years. GIS was used to generate stock figures for each year, and overlay allowed change between survey dates to be estimated.GIS was used to compare data collected from both field survey and satellite imagery so that both sets of information could be qualified when expressed as national figures.This paper describes the historical development of the ITE Land Classification, examines the way in which data were collected for surveys, with particular reference to Countryside Survey 1990, and shows how satellite and field survey data can be linked through GIS.

Morna K. Gillespie, D. C. Howard, M. J. Ness, R. M. Fuller
Primary Databases for Forest Ecosystem Management - Examples from Ontario and Possibilities for Canada: NatGRID

This paper identifies some scientific impediments to ecosystem management and describes bio-physical databases required to help systematically and empirically address the ecological sustainability challenge. Examples are drawn from ongoing work in Ontario. This work has implications for efforts in ecological land classification, landscape ecology, more efficient locating of research and monitoring plots, wildlife management and ultimately trade-off analyses. We conclude with the recommendation that the key primary databases, as currently evolving for Ontario, could and should be developed nationally, thereby creating a “NatGRID database”, i.e., Nationally Georeferenced Resource Information for Decision-making. NatGRID could be used to help address, in a more quantitative manner, fundamental questions regarding ecological sustainability and trade-offs in forest management.

Daniel W. McKenney, Brendan G. Mackey, Richard A. Sims
Forest Dynamics Modelling under Natural Fire Cycles: A Tool to Define Natural Mosaic Diversity for Forest Management

In natural boreal forests, disturbances such as fire and variation in surficial deposits create a mosaic of forest stands with different species composition and age. At the landscape level, this variety of stands can be considered as the natural mosaic diversity. In this paper, we describe a model that can be used to estimate the natural diversity level of landscapes. We sampled 624 stands for tree species composition and surficial deposits in eight stand-age classes corresponding to eight fire episodes in the region of Lake Duparquet, Abitibi, Québec at the southern fringe of the Boreal Forest. For six surficial deposit types, stand composition data were used to define equations for vegetation changes with time for a chronosequence of 230 years for four forest types. Using Van Wagner’s (1978) model of age class distribution of stands, the proportion of each forest type for several lengths of fire cycle were defined. Finally, for real landscapes (ecological districts) of the ecological region of the “Basses-Terres d’Amos”, the proportion of forest types were weighted by the proportion of each surficial deposit type using ecological map information. Examples of the possible uses of the model for management purposes, such as biodiversity conservation and comparisons of different landscapes in terms of diversity and sensitivity to fire regime changes, are discussed.

Sylvie Gauthier, Alain Leduc, Yves Bergeron
Structural Characteristics of Post-Wildfire and Clearcut Landscapes

A continuing discussion in the field of ecology and forest management concerns the implications of clearcutting as a functional replacement for wildfire in disturbance-driven ecosystems. At the landscape level, spatial pattern has been shown to influence many ecologically important processes. Satellite imagery allows the evaluation of structural patterns created by alternative forest management activities at broad scales. In Northwestern Ontario, both clearcutting and wildfire have occurred over large contiguous areas. Spatial characteristics including composition, patch size, patch shape, and interspersion were calculated from classified Landsat Thematic Mapper (TM) data at two thematic scales and used to compare post-wildfire and clearcut landscapes. Patches in the clearcut landscape were found to be larger in size, and had a more irregular shape than those in the wildfire landscape. Differences in landscape structure were much more pronounced at broad scales than at fine thematic scales.

Michael J. Gluck, Robert S. Rempel

Soil Moisture Regime and Site Evaluation

Classification of Moisture and Aeration Regimes in Sub-Boreal Forest Soils

One hundred and two white spruce (Picea glauca (Moench) Voss) stands were studied in the Sub-boreal Spruce zone of British Columbia and were quantitatively classified into seven soil moisture regimes (moderately dry, slightly dry, fresh, moist, very moist, wet, and very wet) according to actual/potential evapotranspiration ratio, depth to gleyed layer or prominent mottling, and depth to groundwater table. The delineated soil moisture regimes demonstrated strong relationships with the composition of understory vegetation and white spruce foliar nutrients and site index. These relationships implied that the three differentiating characteristics used in the classification provided a good estimation of growing-season soil water supply. In addition to soil moisture regimes, three soil aeration regimes (adequate, restricted, and deficient) were delineated according to presence or absence of gleyed horizons and groundwater table, slope gradient, and soil texture. These soil aeration regimes helped in explaining the variation in white spruce site index, especially on water-surplus sites. Thus, an integrated classification of soil moisture-aeration regimes was proposed to explain the effect of soil moisture and aeration on white spruce productivity.The results of this study gave further evidence that soil moisture and aeration regimes, differentiated on the basis of climatic data and soil morphological properties, are useful measures of soil moisture and aeration conditions in sub-boreal forest soils.

G. Geoff Wang, Karel Klinka
Tree Species in Relation to Soil Moisture Regime in Northwestern Ontario, Canada

Selected data on site, vegetation cover, and soil, including soil moisture regime (SMR), were collected from 2 167 field plots in northwestern Ontario, Canada. SMR provides an estimate of an averaged, “annualized” soil moisture supply throughout a complete vegetation cycle. SMR is based upon a relative scale that subjectively ranks sites from θ, 0, and 1 through 9 along a soil moisture continuum which relates to a dry to wet gradient. SMR may be generally correlated to tree growth, stand composition, degree of competition, nutrient availability and overall site quality.This paper reports on relationships between SMR and major tree species. Results highlight relationships between SMR class and the broad ecological ranges of several tree species. In northwestern Ontario, the determination of SMR can help resource managers to better understand the ecology of boreal sites.

Richard A. Sims, Kenneth A. Baldwin, H. Maureen Kershaw, Yonghe Wang
Effects of Decaying Wood on Eluviation, Podzolization, Acidification, and Nutrition in Soils with Different Moisture Regimes

One possible impact of large accumulations of decaying wood on forest sites is an increase in (1) eluviation, podzolization and acidification of, and (2) leaching and loss of nutrients from, the soil directly under decaying wood. As an exploratory investigation, we sampled soils beneath forest floors with and without large accumulations of decaying wood (lignic and algnic forest floors respectively) on three soil moisture regimes. Nine sites were located, three in each of central British Columbia, east Vancouver Island, and east of Vancouver. Among the moist sites, there were no differences in Ae horizon thickness between the alignic and lignic forest floors. However, the Ae horizon was thicker beneath the lignic forest floors (mean 4.2 cm) compared to the alignic forest floors (mean 0.7 cm) in slightly dry and fresh sites. Lignic and alignic forest floors differed (p < 0.01) in pH, total C, total N, mineralizable N, available S, available P, extractable Mg, K and Ca, lipids, C in fraction B (soluble polysaccharide fraction), C in humic acid, C in fulvic acid, and polyphenol C in fulvic acid for all soil moisture regimes. There were no significant differences in the measures of nutrients or indicators of podzolization as measured by organically complexed Fe and Al, the total non-crystalline Fe and Al, and the poorly crystalline Fe and Al, in the underlying 10 cm of the Bf horizon between the two substrates regardless of the soil moisture regime. Further investigations are needed to establish the relationships between soil productivity and the observed soil chemical measures.

G. J. Kayahara, K. Klinka, L. M. Lavkulich

Forest Site Quality and Productivity

Forest Site-Quality Estimation Using Forest Ecosystem Classification in Northwestern Ontario

Site index for jack pine, black spruce and trembling aspen was found to be poorly related to soil types described in the Northwestern Ontario Forest Ecosystem Classification (NWO FEC). Statistical analyses showed that average site indices for most soil types and groupings of soil types were not significantly different from each other.Site index varies greatly within presently defined NWO FEC soil types because certain soil and topographic features that are closely related to site index vary greatly within soil types or are not well described by the NWO FEC soil types. These critical soil features have been identified by soil-site studies that show features most closely related to site index usually are surface soil features found within the effective rooting zone of forest trees. These critical features include depth to bedrock, depth to root restricting soil layers, and coarse fragment content and texture of surface soil horizons.Site-quality research in Northwestern Ontario is closely integrated with the NWO FEC program, thus future NWO FEC soil classifications probably will use results from our soil-site research as a basis for soil type revisions. The result will be future soil types that are more closely related to forest site quality and thus to the capability of forest land to produce tree growth.

Willard H. Carmean
Site Characteristics, Growth and Nutrition of Natural Red Pine Stands in Newfoundland

Red pine (Pinus resinosa Ait.) is rare (< 15 000 mature trees) in Newfoundland and is known from only 22 locations in the central region. Red pine occupies 3 major site types in Newfoundland: 1) red pine on medium-textured sands (RP1), 2) red pine on coarse-textured glacio-fluvial deposits (RP2), and 3) red pine on Folisols over bedrock (RP3). The succession of red pine site types after cutting is from red pine to Kalmia — black spruce (Picea mariana (Mill.) B.S.P.) for RP1, and to Cladonia-Kalmia — black spruce for types RP2 and RP3. Succession after fire is usually to the pre-fire type, but this depends on the severity of the fire.Although occupying a relatively poor site, red pine at 60–70 years reaches heights in excess of 18 m, dbh in excess of 40 cm, and individual tree volumes greater than 1 m3 were recorded in 75 stem-analyzed fire-killed trees. Black spruce on that same site produces less than one-third that volume in 60 years. Merchantable volume of 140–280 m3 ha-1 were recorded i.e., Canada Land Inventory (CLI) forest capability class 5 and class 4 ratings. This raises the CLI rating two capability classes if red pine were occupying these poor quality sites over black spruce. In terms of nutrition, even the best growing red pine are nitrogen (N) deficient as shown by foliar analysis. All natural stands have foliar N concentrations below 1.3% which is the critically low level shown in the literature. Immediately after fire, foliar concentrations reach this level but are usually about 1% or less. Most other nutrients are low but are within the generally reported adequate levels in testing for P, K, Ca and Mg.Fire influences soil nutrient availability as pH increases in the RP1 type. Burning temperature also affects soil pH and the understory vegetation. The RP2 type loses more N in hotter burns on this site type and more N is tied up in these ortstein hardpan soils. The pattern of regeneration following wildfire is related to slope, density, age and species mixture of the stand as well as the thickness and composition of the duff layer.

B. A. Roberts, Denes Bajzak
A Soil-Site Evaluation Index of Productivity in Intensively Managed Pinus Radiata (D. Don) Plantations in South Australia

A limiting-factor, environmental model for radiata pine (Pinus radiata (D. Don)) has been developed using landform and soil morphological features that influence site productivity. The model focuses on soil and landscape constraints to productivity and predicts the native productivity of land and tree species. It permits the integration of land-use objectives for a catchment through forest management and use of silvicultural practices which increase productivity. The soil site evaluation index (SSEI) is an index of forest productivity found when silviculture extends only to the minimum amount of site disturbance needed to establish a plantation of radiata pine. The impacts of intensive silvicultural practices were deducted from the ‘Site Quality’ productivity survey rating to calculate the unimproved yield class (uYC). We calculated SSEI by range standardising uYC values from 0 to 1. SSEI was correlated with the environmental factors in a regression tree model using readily available analytical software. The model accurately predicts unimproved forest productivity from observed soil horizon and land surface properties. The environmental constraints in low lying areas relate to waterlogging, soil sodicity and gravel content. In elevated areas, plant available water storage, rock weathering, landform, ironstone gravel and aspect are recognised factors for pine growth.

I. D. Hollingsworth, R. Boardman, R. W. Fitzpatrick

ELC-Based Management

A Habitat-Based Microscale Forest Classification System for Zoning Wood Production Areas to Conserve a Rare Species Threatened by Logging Operations in South-Eastern Australia

The production of timber from native forests is presently one of the most controversial land management issues in Australia. Part of this controversy results from the potential impacts of forestry practices on forest-dependent fauna, particularly those that are rare and endangered, such as Leadbeater’s Possum Gymnobelideus leadbeateri McCoy, in the forests of central Victoria, south-eastern Australia. A significant proportion of the highly limited distribution of this species overlaps with some of the most valuable wood production forests in Australia within which extensive clearfelling operations are employed to produce timber and pulpwood. These operations can destroy the habitat of G. leadbeateri. The Victoria government agency that is responsible for forest and wildlife management has devised a forest zoning system as part of the management strategies to conserve G. leadbeateri within timber production areas. This is designed to partition the forest into three types of areas: (1) where the conservation of G. leadbeateri is a priority, (2) where wood production is a priority, and, (3) where both land uses are a joint priority. The classification of areas of forest where the conservation of G. leadbeateri is the primary land use is based on an understanding of the habitat requirements of the species. The results of recent field studies, where statistical models of the habitat requirements of G. leadbeateri have been developed and their performance subsequently tested using a new dataset, highlights the need for a new basis to guide the classification of areas for the conservation of the species within wood production forests. We describe a method for devising a forest management zoning system that is based on a statistical model of the habitat requirements of G. leadbeateri and which will better integrate wood production and the conservation of the species. This procedure accounts for the uncertainty in the statistical model and, in turn, reduces the risk that areas where G. leadbeateri occurs are logged, whilst ensuring that other areas are not unnecessarily excluded from timber harvesting.

D. B. Lindenmayer, R. B. Cunningham
Use of Forest Ecosystem Classification Systems in Fire Management

Forest Ecosystem Classification (FEC) systems have been used in the past mainly for forest management decision-making. FEC systems can also serve an important role for decision-making in other disciplines, such as fire management for both wildfire suppression and prescribed burning operations. FEC systems can provide an important means of identifying potential fuels that may be present on a forest site. This fuel information, in combination with current fire weather conditions, as determined by the Canadian Forest Fire Weather Index (FWI) system, can assist fire managers in determining potential fire behaviour if ignition should occur. FEC systems provide a means of identifying the possible presence of a live understory vegetation component, a fuel layer that has been largely ignored in the past due to a lack of information. Dense understory vegetation can produce a very moist microclimate that can effectively hinder fire spread. The use of FEC systems can help in setting priorities on which wildfires need to be attacked aggressively. For prescribed burning, FEC systems can assist in achieving burn objectives better and more safely.

Douglas J. McRae
Forest Ecological Classification and Mapping: Their Application for Ecosystem Management in Newfoundland

A prerequisite to sustaining ecosystems is the inventory and classification of landscape structure and composition. Ecological classification and mapping involves the delineation of landscapes into easily recognizable units. Topography, soils, vegetation, physical landscape form, and successional pathways are delineation criteria commonly used.Damman (1967) developed a forest type classification system for Newfoundland using vegetation, soil and landforms as the defining criteria. Damman’s forest types were used in combination with mensurational data to assign forest types to timber volume productivity classes. Since each of the Damman forest types is associated with characteristic soils, parent materials, moisture regime and topographic position, the mapping units are similar to Canada Land Inventory (CLI) mapping units. Field work to confirm the correlation between Damman forest types and CLI capability classes was initiated in 1993. CLI maps were recoded in 1994 and Damman forest types were determined; resulting ecosystem- based maps provide a common framework to assess forestry/wildlife interactions in an ecosystem planning process.

L. J. Moores, B. Pittman, G. Kitchen
Ecological Land Classification as a Basic Theme for the Management of Wildlands in Tennessee: A Start

The Tennessee Wildlife Resources Agency (TWRA) owns and/or cooperatively manages nearly 247 000 ha scattered across the state. To aid the management of this diversity of soils, landforms, and plant communities, TWRA has selected a flexible, ecological land classification system developed for the Interior Uplands in southeastern United States. Landtypes are the most detailed unit of the 5-level hierarchy. To date, four wildlife management areas and one state wetland have been mapped and entered into the agency s Geographic Information System (GIS). These five tracts are in the Upper Coastal Plain of west Tennessee, in the Western and Eastern Highland Rim regions of middle Tennessee, and in the Cumberland Mountains of east Tennessee. The history, physiography, geology, soils, topography, and vegetation of each area are discussed. After forest cover type and age information is merged with the landtypes, wildlife habitat modelling will commence.

Glendon W. Smalley, Lorenda B. Sharber, John C. Gregory

ELC-Based Research

Genecological Variation Corresponding to Forest Ecosystem Classification Vegetation and Soil Types for Jack Pine and Black Spruce from Northwestern Ontario

A preliminary study was undertaken to reveal ecotypic differentiation in jack pine and black spruce corresponding to ecological land classification groups. Seed sources of jack pine (64) and black spruce (68) from northwestern Ontario were classified according to Vegetation Types (V-Types) and Soil Types (S-Types) defined by the Forest Ecosystem Classification (FEC) developed by the Ontario Ministry of Natural Resources and Forestry Canada for northwestern Ontario. Two short-term common garden field trials and a greenhouse trial were established for each species. Significant differences were present among ecological groupings of seed sources for both species. These differences were expressed according to V-Types and S-Types based on first, second, and third year heights as well as needle flushing dates for jack pine and second year growth increments for black spruce. Rank differences among the groups based on FEC V-Types and S-Types were generally consistent for each of the two species although certain groups showed rank reversals at the two field trials. Apparently, selection pressures corresponding to different FEC V-Types and S-Types have resulted in a detectable pattern of adaptive variation for both jack pine and black spruce in northwestern Ontario. However, the management implications for these two species are uncertain since additional tests are required to verify these results.

William H. Parker, Annette Van Niejenhuis, Joell Ward
Diameter Distribution of Some Subalpine Fir Stands in Central British Columbia

Diameter distributions of subalpine fir (Abies lasiocarpa (Hook.) Nutt.) in central British Columbia were investigated. Nine fire-originated, old-growth stands were selected with maximum tree age at breast height of about 300 years. The stage of stand development was determined by testing how well a negative exponential function matched the cumulative diameter distribution. As a comparison, the negative exponential function was also fitted on the frequency distributions. Eight out of the nine distributions showed fewer medium-sized trees and more large-sized trees than predicted by the negative exponential function. One stand showed relatively good fit, but failed the lack-of-fit test. Although the diameter distributions are close to a balanced stage, stand establishment patterns are still evident 300 years after disturbance.

Pal Varga, Karel Klinka
Metadaten
Titel
Global to Local: Ecological Land Classification
herausgegeben von
Richard A. Sims
Ian G. W. Corns
Karel Klinka
Copyright-Jahr
1996
Verlag
Springer Netherlands
Electronic ISBN
978-94-009-1653-1
Print ISBN
978-94-010-7239-7
DOI
https://doi.org/10.1007/978-94-009-1653-1