Bio-Physical Land Classification in Canada
Transcription
Bio-Physical Land Classification in Canada
29/ Bio-Physical Land Classification in Canada M . JURDANT, D. S. LACATE, S. C. ZoLTAI, G . G . RUNKA, and R. WELLS THE CONFLICT between resource development and environmental quality has its roots in the concept that the environment consists of resources created for man's exclusive use. Recent questioning of this attitude has resulted in a focusing of environmental and ecological research on the control of pollution rather than on the examination of (a) whether or not the proposed resource developments should be initiated, and (b) what are the alternatives available within the ecological system for the proposed resource development scheme. To improve the quality of the environment, man must realize that he is but one part of the ecological system and that the natural resources cannot be abused and squandered. Careful long-term environmental planning becomes the focus and prerequisite for the development of a better environment in which potential pollution problems are identified very early in the decisionmaking process. Proposed development programs can then be evaluated, not only from the standpoint of "how can the environmental impact be ameliorated once a program is initiated", but more importantly, "from an environmental standpoint, how should the program proceed?". Land management and land-use planning for developing a better environment must, therefore, be based on an understanding of the overall structure and functioning of the natural ecosystems. These ecosystems must be understood at various levels of integration (14), from the entire biosphere down to a sugar maple-yellow birch community on a specific site. One of the essential frameworks for environmental management, therefore, is an inventory of ecosystems at a level, and at a scale and intensity, appropriate to the management objectives. M. Jurdant. S. C. Zoltai, and R . Wells are R esearch S cientists, Canadian Forestry S ervice, respectively located at the Laurentian Forest Research Centre , Ste. Foy , Que. , the N orthern Forest Research Centre, Edmonton, Alta., and the Ne wfo undland Forest R esearch Centre, St . John 's , Nfld. D. S. Lacate is R egional Director, Lands Directorate, Canada Dept. of the En vironment , Vancouver, B.C. , and G. G. Runka is S oils S cientist, British Columbia Land Commission , Burnaby, B.C. 485 486 JURDANT. LACA TE. ZOLTA I. RUN KA . AND WELLS History of Ecosystem Classification in Canada In Canada, ecosystem classifica tions we re initially de ve lo ped on the ba sis of a variety of criteria ranging from purely phytosociological to purely physical (I , 15). A common platform was reach ed thro ugh the National Committee on Forest Land s when a subcomittee on bio-physical la nd cl assifica tion was created in 1966 which proposed the undertak ing of pilot projects in British Columbia, Manitoba , Quebec, N ova Scotia , a nd Newfoundland. The result was the publica tion of guidelines for a bi ophysica l la nd class ifica tio n (13), with emph asis on th e development of a methodology for reconn a issance surveys to provide an overview a nd in ventory of forest land and associa ted wildland resources. The va lue of this type of inventory is that it can bring together information for la rge inaccessible regions an d identify th ose areas where more detail m ay be needed in the future. A bio-physical classificati on provide s a n ecological basis for la nd -use pla nning (9), since it provides a geographical framework for the system at ic study of ecosystems and the extrapolation of the resulting knowledge. Thi s information can serve as a framework for the assessment of reso urce ma nagement progra ms, environmental impacts, and long-te rm environmental research requirements. Objectives of the Bio-Physical Land Classification System The objectives of the bio-ph ys icalland cla ssification are: I) To describe and characterize the biological and physical fe a tures of the land and to organize knowledge into a useful fra mework for the ma nagement of the land. This includes the classification and ma pping of th e following : climatic regions geology phys iography and landforms texture, petrography, and depth of the surficial geological materials soil physical, chemical , and biological characteristics of wa ter bodies structure, physiognomy, and composition of vegetation succession of vegeta tion (ch ronosequences) . In order to obtain a thorough understanding of relationships between the living (flora, fauna, man) and the non-living (land, water, climate) environment, emphasis is given to features having the highest degree of interrel a tionship . 2) To interpret and evaluate the biological productivity, based on identified bio-physical units and characteristics of the land, to provide the resource manager with data for planning land use or development. BIO-PHYSICAL LAND C LASSIFICATION 487 3) To provide a comprehen sive and integrated geographical explanation of the environment, leading to an understanding of the interrelationships between living and non-living parts. Concepts Va rious concepts have influenced the bio-physical land classification system . The Australian system (3, 4, 5, 6) and the Ontario system (7, 8) can both claim parental rights, but the influence of many other workers is also evident; among these are the soil scientists of the Canadian Soil Survey Committee (2, 18) and Rowe's concepts on ecosystems (15). The various pilot studies conducted in different environments throughout the country have had major inputs into the present Canadian viewpoint on bio-physical land classification. The philosophy of the classification system rests on the recognition that, although all environmental factors (landform, climate, organisms, soil, and ground water within a framework of time) influence each other, the landforms (including structure and composition as well as form of terrestrial and water bodies) influence the other factors to a far greater degree than they are influenced by them . Thus, landform classification and mapping are the framework within which climatic, vegetational, pedologic, and hydrologic data are described, characterized, and classified . The Levels of Ecological Integration ·. The inventory of ecosystems must be made at different scales and intensities to serve the environmental planning objectives for different levels of social organization and institutions: the country, the province, the socioeconomic region, the city or municipality, the family. A hierarchical system is therefore needed which permits a choice of the degree of detail required to meet the purpose of a particular survey. The following five levels of ecological integration are now recognized; they are listed from the more general to the more specific (Table I): Land Region: an area of land characterized by a distinctive regional climate as expressed by vegetation . The mapping scale is in the order of I : 1,000,000 to I : 3,000,000. Regional vegetation and physiographic pattern are the major differentiating mapping characteristics, although complexes of landforms and of soil characteristics (e.g. permafrost) are also used as indicators. Climatic data are used to characterize the mapped units infrequently, partly because of the scarcity of data throughout most of Canada, partly because of the very limited knowledge on the significance of climatic data for various """ 00 00 Table I. Levels of ecol ogical integration of a bio-physicalland classification LEVEL OF INT EG RATION 2 3 4 5 Land Type Land Phase BIO-PHYSI CAL U IT SCALE Land Region 1/ 1,000,000 1/ 250,000 1/ 125,000 1/ 20,000 1/ 10.000 H UMAN COM MUN ITY OF REFERENCE Country Province Regi on Municipality Family MOST ACT IVE ECOLOG ICAL VARIAB LES Regional climate Phys iogra phy Landform Soil and topog raph y Man . mic roclim ate a nd disturbances La nd District Land System '- c CRITERIA OF DIFFERENT IATION a Regio na l climate H H H H H Relief P H H H H Bedrock geo logy X P H H H Landform s X P P H H '" 0 » Z ;-I r » » () -I !" N 0 r -I » :- P P H H Soil developme nt X P P H H Vege ta ti on ch ronosequence X P P H H Soil thickness, texture , and petrog ra phy X P H H 0 Soil moisture regi me X P H H Surface organ ic ho rizon X X H m r r Phys ionomy and stru cture of vege tati on X X H Compositi on of vege tati on X X H Topographic position a H ; Criteria ho mogeneous throughout the unit : P : C riteria wh ose di stributi on is organized : a patrern : X : Criteri a wh ose di stri buti on is erratic : a co mplex. '"cz '" 1> » z ~ Ul BIO-PHY S ICA L LAND C LASSIFIC ATION 489 management uses, and partly because many elementa ry, but important, climatic-bio-physical interrelationships are not clearly understood . Land District: an area of land characterized by a distinctive pattern of relief, geology , geomorphology, and associated regional vegetation. This is the level which corresponds most closely with the notion of "pays ", or " terroir" , or "landscape " . The mapping scale is I: 250,000 or I : 1,000,000. The Land District is a subdivision of the Land Region . Land System: an area for which there is a recurring pattern of landforms, soils, and vegetation chronosequences. Some surveys have added patterns of water bodies in the definition of the Land System (11), others have grouped Land Systems and water bodies into broader units called "Landscape Units" (19). The mapping scale is I : 100,000 to 1 : 250,000. This is the working level of most of the reconnaissance bio-physical surveys completed to date in Canada . Land Systems can be viewed as a subdivision of a Land District or as a characteristic pattern of Land Types, the next lower level of ecological integration. Land Type: an area of land having a fairly homogeneous combination of soil (e.g. Soil Series) and chronosequence of vegetation . It is the basic ecological cell of the bio-physical classification, the one upon which most of the biological productivity and other interpretive ratings can be made . They can be delineated at scales ranging from I: 10,000 to I : 60,000. Land Phase: an area of land having a fairly homogeneous combination of soil and vegetation . It is a subdivision of the Land Type based on the stage of vegetation succession as expressed by the existing vegetation at the time of the survey . Methods , . Most bio-physical surveys to da te in Canada have been underta ken at a relatively small scale or reconnaissance level (1 : 125,000), mainly to serve as the ecological basis for regional land use planning. In spite of considerable variation in methods, related to the nature of landscapes, and of availability of specialists in the survey teams, all pilot projects showed a successful application of the guidelines as outlined by the National Committee on Forest Lands. The guidelines were intended to be only a preliminary framework which would be revised and modified as indicated by the participants in the various pilot projects. The system is now beyond the stage of pilot projects and is in the operational stage in several regions . The following is an attempt to summarize the method in the light of recent surveys in British Columbia (16), Manitoba (19), Ontario (9), Quebec (10, II), Labrador (12) and Newfoundland (17). 490 JU RDANT, LA CAT E, ZOLTAl , RUN KA , AND WE LLS I) The basic bio-physical classification is derived from an a priori integra tion of the knowledge of climate, geology , geomorphology, soils , and vegeta tion collected by a team of specialists in various disciplines working together in the field and in the office. The a priori integra tion is preferred to an a posteriori integration commonly obtained by superimposing sectorial m a ps (geomorphology, soil, vegetation, etc.) which are not only more expensive to produce, but create complications due to minor variations in unit boundaries developed independently by each discipline . 2) Pre-field interpretation of small-sca le aerial photographs is undertaken to delineate preliminary Land Systems. The initial breakdown is based mainly on topography , depth of unconsolidated geological material s, and landforms. 3) The preliminary maps are used to stratify the fi eld mapping transects a nd the benchmark ecosystems to be de scribed in the field . Sampling is preferred where the steepest gradients along toposequences, c1imosequences, lithosequences, and chronosequences occur. 4) The field work comprises the following concurrent activities : the determination of the ecologically effective climate over l;uge areas (Land Regions) by comparing chronosequences on similar edaphophysiographic conditions; the sampling of benchmark ecosystems whose classification determines the ecologically effective segments of the land (La nd Types) under each given climatic condition; the checking of mapping boundaries. 5) Field observation data are compiled to arrive at a classification of the Land Types. 6) The final Land Systems map is produced and the units are defined in terms of the relative area percentages of the constituent Land Types . 7) The Land Systems are described and subdivided or grouped on the ba sis of similarities of the water bodies. Important characteristics are : configuration, size, depth, shore materials, dissolved solids , turbidity. 8) The management interpretations of the Land Types and the Land Systems are developed in cooperation with experts in the various resource disciplines including foresters, agronomists, wildlife biologists, recreationalists, civil engineers, regional planners, and hydrologists . Interpretations for Environmental Management Ecologists, pedologists, and phytosociologists have produced many classifications and maps of a high intrinsic scientific value, but often of limited use to the land manager. Too often these documents were designed for other ecologists, pedologists, and phytosociologists ; they may ha ve been . , BIO·PHYSI CA L LAND CLASSIFICATION 491 cited in international publications, but land managers often could not assess them in practical terms and transform them into action. This situation has led to grouping of land ecologists and resource managers into multidisciplinary teams with a much greater "interpretive power" . It is only through the combined inputs of various specialists that interpretation s and management recommendations, which are relevant to the field of resource development planning and management, can be developed . Several interpretations of the bio-physicalland units for area planning and land management purposes have been achieved with varying degrees of success, depending on the complexity of the area studied and the level of ecological integration chosen . Interpretations from completed surveys follow : •• I. Agriculture: • land capacility for agriculture in 7 classes • land suitability for various crops • surface erosion potential • agricultural management problems of the mapped units such as: soils requiring irrigation or drainage soils subject to flooding soils of fine (heavy) texture and poor structure with heavy power requirements for cultivation soils subject to wind erosion and sand blasting soils likely to be nitrogen deficient soils likely to be sulfur deficient soils likely to be affected by compaction, poor root penetration, surface puddling, and crusting soils low in organic matter soils likely to have high land-clearing costs soils with short frost-free periods soils subject to overgrazing. 2. Forestry: • land capability for forestry in 7 classes • timber production potential in volume/unit area/year • plantation difficulty • land suitability for various species (plantations) • establishment cost of plantations • production cost of plantations • windthrow hazard • trafficability • potential of natural regeneration • plant competition following harvesting 492 JURDANT. LACATE. ZOLTAI. RUNKA. AND WELLS • • • • aggressive species following harvesting aggressive species following fire soil damage by harvesting type of damage expected during and subsequent to timber harvesting operations: increased erosion, destruction of soil structure, stream sedimentation, increased slide hazard, etc. • recommended slash disposal methods • recommended management practices which best protect the soil and water resources, i.e. no logging, winter logging, skidding across slopes to minimize erosion, etc. 3. Recreation: • land capability for recreation in 7 classes • recreation potential of water bodies • landscape attractiveness • land suitability for various recreational uses such as: intensive camping and picnic sites building sites paths and trails intensive play areas cottaging artificial lakes • ecological damage hazards subsequent to intensive recreational use • recommended species for aesthetic reforestation. 4. Wildlife: • land capability for ungulate wildlife in seven classes • land capability for waterfowl wildlife in seven classes • sedimentation yield potential in water bodies, following timber harvest, road construction, and other activities • land capability for various plant species important for wildlife such as: mountain maple, lichens, herbaceous species, willows, etc. • vegetation succession trend probability. 5. Water: • water holding capacity of soil and land units • sedimentation yield potential in water bodies following timber harvest, road construction, and other activities. 6. Engineering: • land suitability for engineering use • topsoil suitability • suitability as source of sand and gravel • suitability as source of fill material • soil features affecting road location BIO-PHYSICAL LAND CLASSIFI CATION 493 • • • • • • • soil features affecting foundations for low buildings soil features limiting use for septic tank filter fields soil features affecting use for sewage lagoons soil features affecting use for pipelines flooding hazards ecological damage hazards subsequent to flooding susceptibility of permafrost terrain to damage_ These interpretations can be expressed on an areal basis for the smallest land unit level permitted by the nature of the study_ The inescapable subjectivity of many of these evaluations is counterbalanced by the possibility of re-evaluating the basic bio-physical mapping ecosystem units as new information and research related to the management of the land becomes available_ Applications The bio-physical survey is an environmental survey which constitutes the ecological framework of an area for the following activities. I) Framework for assessment of environmental impacts of major developments (e.g. James Bay Development Project, Quebec), roads and transportation corridors (e.g. Mackenzie River Valley, North West Territories and Yukon), flooding (e.g. South Indian Lake, Manitoba), urban development, large scale logging operations, and farm abandonment. ... 2) Framework for land-use planning. Since the bio-physical map provides a single permanent framework within which the natural renewable resources are rated as to their potential production, it constitutes a suitable geographical basis for zoning. This information identifies the management options available within the region in question. The zoning that could be delineated would identify not only the areas of exclusive use, but also the areas of compatible and complementary uses, as well as the ecologically sensitive areas which require a high level of management integration. 3) Framework for environmental management. The bio-physical survey provides an appreciation of the interaction of the environmental factors that must be considered in single or multiple resource management. For example, a program of reforestation of abandoned farmlands in a given sector should consider the following interpretations provided by the bio-physical survey: - the timber production potential the planting difficulty the trafficability the species suitability the landscape attractiveness the land capability for agriculture 494 JURDANT, LACATE, ZOLTAI , RUNKA. AND W ELLS the land capability for recreation the erosion hazards the windthrow hazards. Operationally, the Bio-Physical Land Classification guidelines are being used, in part, as a basis for recent ecological inventories in several national park s. 4) Framework for research and future surveys. The ecologically significant units delineated on the bio-physical map provide the scientist with a framework which allows him to extrapolate his research results and to orient his research input towards those land areas which have the greatest significance. The bio-physical survey also provides a framework for follow-up investigations, either by other resource agencies or for surveys at a more detailed level as need s or concerns are identified. Conclusions Within Canada, operational bio-physical surveys have been ca rried out or are planned in several regions: British Columbia, Northwest Territories, Manitoba, Ontario, Quebec and Labrador. There are, at present, criteria and procedures that have served us well in our endeavour to characterize and evaluate land resources within the Canadian landscape. When properly interpreted and applied, these classi fi ca tions have provided the land manager with units which have distinct ecological significance for a variety of management needs. Continued interdisciplinary inputs will be required to incorporate these data into realistic environmental management plans. Literature Cited I. Burger, D. 1972. Forest site classification in Canada. Mitt. Ver. Forstl. Standortskunde ForstpflZucht. No. 21. 39 p. 2. Canada Department of Agriculture. 1970. The System of Soil Classification lor Canada. Queen's Printer for Canada, Ottawa. 249 p. 3. Christian, C. S . 1952. Regional land surveys. J. Aust.lnst. Agric. Sci. 18: 140- 146. 4. Christian, C. S. , T. Nakano, D. Steiner, and H. T. Verstappen. 1968. Nature of integration and the limitations of integrated surveys. In Aerial Surveys and Integrated Studies, r. 533-539. Proc. Toulouse Conf., (1964) , UNESCO, Paris. 5. Christian, C. S ., and G. A. Stewart. 1952. Genera l report on survey of Katherine-Darwin region, 1946. Land Res. Serv., Commonw. Sci. Ind. Res. Organ. Aust. Rep . No. I. 156 p. 6. Christian, C. S., and G. A. Stewart. 1968. Methodology of integrated survey. In Aerial Surveys and Integrated Studies, p. 233-280. Proc. Toulouse Conf. (1964), UNESCO , Paris. 7. Hills, G. A . 1960. Regional site research . For. Chron. 36: 401-423 . 8. Hills, G. A. 1961. The ecological basis for land-use planning. Ontario Dcp . Lands For., Res. Rep. No. 46. 204 p. 9. Hills , G. A. , D. V. Love, and D. S. Lacate. 1970. Developing a better environment. Ecological land-use planning in Ontario-a study o f methodology in the development of regional plans. Ontario Economic Council, Toronto. 175 p. ,. BIO-PHYSICAL LAND CLASSIFICATION . -. 495 10. Jurdant, M. 1968. Ecological classification of forest lands , an integrated vegetation-soillandform approach. Ph.D. Thesis. Cornell University, Ithaca, N.Y. 414 p. II. Jurdant, M., J . Beaubien , J. L. Belair, J. C. Dionne, and V. Gerardin. 1972. Carte ecologique de la region du Saguenay-Lac-St-Jean-Notice explicative. Can. Fo r. Servo Inf. Rep. Q-F-X-31. 3 vol. 12. Jurdant, M., R. Wells , R. Fulton, B. Dela ney , G. Kitchen , and O. Forsey. 1971. Ecological survey of the Goose Bay Area, Labrador, Newfoundland. Progress Report . ProC. Nat. Comm. on Forest Land Work Meeting, Kamloops, B. C. 94 p. 13 . Lacate, D. S., 1969. Guidelines for bio-physicalland classification. Can . For. Servo Publ. No. 1204.61 p. 14. Rowe , J . S. 1961. The level-of-integra tion concept and ecology. Ecology 42 : 420-427. 15 . Rowe , J. S., 1962 . Soil, site and land classification. For. Chron. 38: 420-432. 16. Runka , G. G. 1972. Soil resources of the Smithers-Hazelton Area. British Columbia Dep. Agric., Soil Surv. Div., Kelowna, B.C. 233 p. 17. Wells, R. E., J. P. Bou zane , and B. A. Roberts. 1972. Reconnaissance land classification of the Corner Brook Area , Newfoundland. Can. For. Servo Inf. Rep . N-X-83 . 123 p. 18. Zoltai. S. C. 1970. Biophysica l land classification system and survey. Proc. 8th Meet. Can . Soil Survey Comm., Ottawa. p. 139-145. 19. Zoltai, S. c., E. T . O swa ld, and C. Tarnocai. 1969 . Land classification for land evaluation: Cormorant Lake Pilot Project. Can. For. Servo Inf. Rep. MS-X-20. 31 p. THIS FILE COPY MUST BE RETURNED TO: INFORMATION SECTION, NORTHERN FOREST RESEARCH CENTRE, 5320- 122 STREET, EDMONTON, ALBERTA. T6H 3S5 This is a reprint from Forest Solis and Forest Land Management Proceedings of the Fourth North American Forest Soils Conference held at Laval University, Quebec, in August 1973 Edited by B. BERNIER and C. H. WINGET 1975, Les Presses de I'Universite Laval ISBN : 07746- 6716- 8 @ Book available in cloth binding @ $18.90 a copy Les Presses de I'Universite Laval C.P. 2447, Quebec G1K 7R4, Canada Distribution ., IN THE UNITED STATES International Scholarly Books Services, Inc . P.O. Box 4347, Portland . Oregon 97028 IN EUROPE Librairie Vuibert 63, boulevard Saint-Germain 75005 Paris, France