Annex B. Review of Existing Global Ecological Zoning Systems
The main purpose of this Annex is to list and give some relevant particulars about the currently available climate, ecological zone or potential vegetation maps that cover the whole globe. An account of the relationship between climate and vegetation, and the theory behind defining ecological zones, or ecoregions, is given by Giovanni Preto in A proposal for classifying and mapping the world’s ecofloristic zones for FRA 2000 (1998). The main text of the current document outlines the needs of the FRA and discusses some of the maps that may be suitable for use in defining zones for this.
The global maps described below primarily define climatic ecological zones. Two of them particularly emphasise differences in biogeography or species origins: the Udvardy (IUCN-UNESCO MAB) map and the WWF-US maps. Some regional maps also emphasise the biogeographical/phylogenetic aspect. Regional maps that show vegetation types but do not emphasise ecological zones are not included in these descriptions but are listed at the end of the annex.
Map of Köppen and Trewartha's climate classification
Köppen, W. 1931. Grundriss der klimakunde. Walter de Gruyter, Berlin.
Trewartha, G.T. 1968. An introduction to climate. 4th Ed. McGraw-Hill, New York.
There is a digital map usable at a scale of 1:30,000,000 available though FAO. No details are available on the origin of the map. This map shows five major Köppen climatic types based: Polar, Cold, Temperate (humid), Tropical (humid), Dry. A number of subclasses are distinguished, which brings the total number of categories mapped to 14.
Because many of the ecological zone maps described below use some major climatic criteria to distinguish their classes, it is deemed worth the effort to list the climatic classes of Köppen that are mapped here for the globe. These are: E (polar climates with extremely cold winters and summers) subdivided into ET: tundra, EF: frozen; D (moist mid-latitude climates with cold winters) subdivided into DF: wet all seasons, DW: dry winters; C (moist mid-latitude climates with mild winters) subdivided into CF: continually moist subtropical, CW: winter dry sub-tropical, CS: summer dry subtropical (mediterranean); B (dry climates with deficient precipitation during most of the year) subdivided into BS: semi arid, BW: desert; A (tropical moist climates) subdivided into AF: continually wet tropical, AM: tropical monsoon, AW: seasonally dry tropical. These classes are quite coarse and do not always correspond directly with other Köppen classes used in the literature.
Map of Holdridge’s life zone system.
Holdridge, L.R. 1967. Life Zone Ecology. Tropical Science Center, San Jose, Costa Rica. 206 pp.
Holdridge’s work was aimed to correlate world plant formations with simple climatic data. The system embraces all major environmental factors in three hierarchical tiers.
Level I – The Life Zone. This is determined by specific quantitative ranges of long-term average annual precipitation, mean annual biotemperature and potential evapotranspiration ratio. These are modified for montane systems.
Level II - The "Association". This is an area of land which, under undisturbed conditions, supports a distinctive natural community adapted through evolution to a specific narrow range of atmospheric and edaphic conditions. No Association can occur in more than one Life Zone.
Level III – The successional stage or cover type, which takes into account that the community may not be in its climax state, either through natural causes or through human intervention.
A map of the Level I Life Zones of the globe is available in digital form, usable at a scale of 1:30,000,000. It is however raster-based and quite coarse. It was prepared by Rik Leemans, who was then working in the Biosphere Project in IIASA, Laxenburg. The mapped classification does not differentiate montane communities as such but uses the major cooler climatic types to denote the montane progressions. This map was used for the non-tropical areas of the world in an exercise by the World Conservation Monitoring Centre (WCMC) and the Center for International Forest Research (CIFOR) to investigate global forest protection by forest type and ecological zone (Iremonger, S., C. Ravilious and T. Quinton (1997.). A statistical analysis of global forest conservation. In: Iremonger, S., C. Ravilious and T. Quinton (Eds.) A global overview of forest conservation. Including: GIS files of forests and protected areas, version 2. CD-ROM. CIFOR and WCMC, Cambridge, U.K. http://www.wcmc.org.uk/forest/data/cdrom2/).
There are many national maps available for Life Zones, particularly in the Americas.
Map of Walter’s Zonobiomes
Walter, H. and E. Box1976. Global classification of natural terrestrial ecosystems. Vegetatio 32: 75-81, with map.
Walter ,H. 1979. Vegetation of the Earth. 3rd Ed. Springer-Verlag, Berlin.
This is a map of an ecological classification of the world’s climates. It is based on the climate-diagram pattern of Walter, in which temperature and rainfall are correlated to show periods of aridity and humidity, in relation to plant growth. Also taken into account are number of frost days and other extremes that influence vegetation pattern. There are nine different major zonobiomes, which have modifiers added if they are particularly dry, cold or wet. The map is only available in paper copy, at a scale of 1:30,000,000. The continents are shown as distinct entities on the map, not joined into one complete global picture.
Walter's work on the Zonobiomes goes beyond what is mapped, describing the different major variants within the zonobiomes, named pedobiomes and orobiomes (edaphic or altitudinal factors). Ecotones between the major zonobiomes are also described.
Bailey's Ecoregions map of the world
Bailey, R.G.1989. Explanatory supplement to Ecoregions map of the continents. Environmental Conservation 16: 307-309 with separate map at 1:30,000,000 scale.
Bailey, R.G. 1998. Ecoregions map of North America: Explanatory note. Misc. Publ. 1548. Washington DC: USDA Forest Service. With separate map at 1:15,000,000.
The purpose of the work, which began in 1976, was to show how the national forests of the United States fit within the global ecoregional scheme. In this system an ecoregion is defined as any large portion of the Earth's surface over which the ecosystems have characteristics in common. There are three levels in this classification system, the Domains, the Divisions and the Provinces.
Ecoregions of the continents are based on macroclimate (i.e., the climate that lies just beyond the local modifying irregularities of landform and vegetation). The theory behind the approach is that macroclimates are among the most significant factors affecting the distribution of life on Earth. As the macroclimate changes, the other components of the ecosystem change in response. Macroclimates influence soil formation and help shape surface topography, as well as affecting the suitability for human habitation.
Four Domains were defined: Polar, Humid temperate, Humid tropical and Dry. The combination of temperature and rainfall to indicate major climatic zones was based on Köppen and Trewartha's work, where dry climates were treated as a separate entity from Tropical humid and Temperate humid. However, the Köppen system defines an addtional "Subtropical" division at this level.
The next level in the Bailey system is the Divisions, and these are also climate - based, for example in the Humid temperate Domain there is Hot continental, Warm continental, Subtropical, Marine, Prairie and Mediterranean, all with Mountain variants (i.e., a total of 12 Divisions in this Domain). There are a total of 30 of these.
The third and last level are the Provinces, which are based on physiognomy of vegetation, modified by climate. For example, the Forest-Meadow of Eastern Oceanic (Monsoon climate). There are a total of 98 of these subdivisions.
The global map has been digitised and converted to a geographic (lat/long) projection by the WCMC, Cambridge, UK. It is also available on CD from NOAAs National Geophysical Data Center in Boulder, Colorado as part of their Global Ecosystem Database Project. http://www.ngdc.noaa.gov/Store/.
Bailey has also drawn a more detailed map of the Ecoregions of North America. This uses the same system as the global map and defines 63 Provinces.
All maps are available in map form from the author: Robert G. Bailey, USDA
Forest Service, 3825 E. Mulberry St., Fort Collins, CO 80524 USA
(email: rbailey/[email protected]).
The map can be downloaded in digital form from the U.S. Forest Service Inventory & Monitoring Institute's web site, which is:
Milanova and Kushlin's map of Present Day Landscapes
Milanova, E.V. and Kushlin, A.V. 1993. World Map of Present-Day Landscapes. An Explanatory Note. Prepared by Moscow State University and the United Nations Environment Programme. 1:15,000,000 scale.
This was prepared using existing maps also authored by Moscow State University "Geographical belts and zonal types of landscapes of the world" and "Land use types of the world", as well as remote sensing imagery and sample field observations. The world is first broken into temperature-defined zonal belts and one intrazonal belt, thus: Polar, Subpolar, Temperate, Subtropical, Tropical, Subequatorial, Equatorial and Intrazonal (8 divisions). Within these are the Landscapes, which are primarily based on the natural land cover and its associated soil type. There are 39 of these, which are the most useful units on this map for the FRA ecological zoning exercise. Each polygon that represents one of these types is then given a letter indicating degree of alteration - whether it is virtually undisturbed ("Modal Landscape"), with moderate interference (e.g., secondary vegetation), with strong intereference (crop cultivation) or with extremely strong change (e.g., towns).
The map is available digitally and in paper copy from Moscow State University. Copies are also held in the WCMC, Cambridge.
Olson and Watts' map of Major Ecosystem Complexes (1982)
Olson, J.S. and J.A. Watts 1982. Major ecosystem complexes. Ranked by carbon in live vegtetation. Oak Ridge National Laboratory, Tennessee, USA.
Olson, J.S., J.A. Watts and L.J. Alliaon 1982. Carbon in live vegetation of major worlds ecosystems. ORNL-5862. Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37830, USA.
The purpose of this map was to attempt to quantify carbon in live vegetation. The primary division in the mapped classes includes a mixture of criteria: plant formations, edaphic factors (a Wetland class is distinguished) and areas altered by human activity. This map is not considered to be one of the principal sources of information contributing to the ecological zoning system of the FRA, because it maps actual land cover rather than potential.
It was originally printed at a scale of 1:30,000,000, and is available digitally from the WCMC, Cambridge.
Udvardy's map of the Biogeographical Provinces of the World
Udvardy, M.D.F. 1975. A classification of the biogeographical provinces of the world. Occasional Paper No. 18. IUCN, Morges, Switzerland.
This map was prepared by IUCN as a contribution tot he UNESCO MAB Programme. The main purpose of the work was to devise a satisfactory classification of the world's biotic areas for purposes of conservation. It is the fourth attempt in a series of revisions, updating the previous three works written by Dasmann.
The logic behind the system was that the plant and animal world occurs within the biosphere of the Earth in the form of an intertwined network of individuals, populations and interacting systems. To be able to view them in a systematic way, the biologist may use the following approaches:
Phylogenetic order (origins and history)
Biogeographic order - grouping the above entities on a geographic basis.
To define geographic units for conservation purposes the following were considered: (a) the distribution of species and (b) the distribution of ecosystem units. The result was a system serving both aims, a hierarchical system of geographical areas which would give a framework for conserving species as well as ecologic areas. These hierarchical Biogeographical entities were named Realms, Biomes and Provinces.
The first subdivision, the Realm, used the phylogenetic subdivisions of the world, unifying those for flora and fauna. It is a continent or sub-continent-sized area with unifying features of geography and flora/fauna/vegetation. Eight Realms were distinguished. The second division is the Biome. These were not the same as the major vegetation formations of the world (see UNESCO, 1973), but combine the features of a major vegetation type with climate. There are 14 of these. These were largely based on the work of Dasmann. The third, most detailed, subdivision was the Province, delimited on a faunal, floral and ecological basis. There are 186 of these.
The map is available digitally from WCMC, Cambridge. It is usable at a scale of 1:30,000,000.
FAO/LET maps of Ecofloristic Zones for the tropics
Lavenu, F., M.F. Bellan and C. Meste 1988. Carte ecofloristique de l’Amerique du Sud. FAO, Rome.
Sharma, M.K. 1986. Ecofloristic zone and vegetation maps of tropical continental Asia. FAO, Rome.
FAO. 1989. Classification and mapping of vegetation types in tropical Asia. FAO, Rome.
Sharma, M.K. 1988. Eco-floristic zone map of Africa. FAO, Rome.
These maps were prepared for the dual purpose of providing ecological categories for the FRA 1990 and also to map vegetation types of the world. These maps only cover the tropical regions and were produced separately, although they use the same systems. Their primary division , take non the whole, therefore, is geographical. There are three different regions mapped: Africa, Latin America, S and SE Asia.
Within each different map, 13 different "Ecological zones" were distinguished using climatic conditions, with an altitudinal element featuring prominently. Five of the classes are montane. Within these classes the Ecofloristic Zones are defined. These have a more detailed physiognomic descriptor and include the vegetation formation as well as a geographic criterion. These maps were used to distinguish ecological zone characteristics for the tropical area in the study by WCMC and CIFOR mentioned above (see the Holdridge section) and by WCMC in a previous exercise investigating protection of land by ecological zone (Green, M.J.B., M.G. Murray, G.C. Bunting and J.R. Paine (1997). Priorities for biodiversity conservation in the tropics. WCMC Biodiversity Bulletin 1. WCMC, Cambridge, UK).
The maps are available form the Laboratoire d’Ecologie Terrestre (LET), Toulouse, or in digital form from FAO. They operate at a scale of about 1:5,000,000.
The WWF-US Terrestrial Ecoregions of the World
Dinerstein, E., Olson, D.M., Graham, D.J., Webster, A.L., Primm, S.A., Bookbinder, M.P. and Ledec, G. 1995. A Conservation Assessment of the Terrestrial Ecoregions of Latin America and the Caribbean. Published in association with The World Wildlife Fund. The World Bank, Washington, DC.
Olson, D.M., E. Dinerstein, E. Wikramanayake, J. Morrison, T. Ricketts, E. Underwood, L. Itoua, Y. Kura, H.E. Strand, C. Loucks, T. Allnutt, W.Wettengel and P. Hurley. (in prep.). Terrestrial ecoregions of the world for conservation planning. WWF-US.
The purpose of this study was primarily to make a tool for the identification of geographic priorities for biodiversity conservation. The result is a system of regional-scale biogeographic units called ecoregions. These are described as relatively large units of land or water containing a geographically distinct assemblage of natural communities sharing a large majority of their species, dynamics and environmental conditions.
The global coverage was drawn up on a continental basis, and not all parts of the world are currently available. The rationale behind this was so that the major split in the global map would be by biogeographic realm. However, the splits were made on political bases, not phylogenetic. Despite this the authors found the division practical for the conservation analyses for which the maps were intended. The methodology for making the maps included collaboration with regional experts as well as the use of a great number of previously published national and regional maps, including some from of Holdridge and McKinnon's Indomalayan Realm study. Udvardy's map was apparently not used. The examples below are taken from the Latin America study.
The primary subdivision, within each geographical region (continent) was into six mainly formation-based categories called Major Ecosystem Types, which were then subdivided into 14 Major Habitat Types, which are comparable to the concept of Biome, as used by Udvardy. These were further classified according to a "Bioregion", of which, for example, there were nine in Latin America. In total there were 91 of the final class, Ecoregion, in Latin America.
For copies of these maps, in paper or in digital form, please contact WWF-US Conservation Science Program,World Wildlife Fund, 1250 24th Street, NW, Washington DC, 20037-1175, USA.
McKinnon's Original Habitat Types of the Indomalayan Realm
MacKinnon, J. 1996. Protected Areas Systems Review of the Indomalayan Realm. Asia Bureau for Conservation, UK.
The purpose of this map was to aid an evaluation of the coverage and conservation importance of the existing protected areas system of the Realm, and to identify sites of global priority for conservation. The map of Original Habitat Types shows both habitat types and biogeographical units. Udvardy identified 27 units in the Indomalayan Realm in 1975. These were further subdivided, and this map shows a total of 90 subunits.
The habitat types were derived from a number of vegetation map sources, often more than one per country, which are listed in the report. There are 62 of these. They are not gathered into a hierarchical system. The map is digital, and may be used at a scale of 1:5,000,000. The report is available from the Asian Bureau for Conservation, 88 Wincheap, Canterbury CT1 3RS, UK, and the digital map is available from WCMC, Cambridge.
Maps of the natural vegetation of different regions/continents of the globe
Bohn, U. and Katenina, G.D. 1994. Map of Natural Vegetation. Komarov Botanical Institute, St Petersburg. Scale 1:2,500,000. Note: this has recently been used a as a base map for the delimitations of European Ecoregions in the WWF-US system of Ecoregion classifcation.
Carnahan, J.A. 1989. Australia - Natural Vegetation. Australian Surveying and Land Information Group, Department of Administrative Services. 1:5,000,000 scale.
Hueck, K. 1972. Mapa de la vegetación de America del Sur. Gustav Fischler Verlag, Stuttgart. 1:8,000,000 scale.
UNESCO. 1980. Vegetation map of South America. UNESCO, Paris.
White, F. 1983. The vegetation of Africa. UNESCO, Paris.