Biogeoclimatic Ecosystem Classification Assigned Reading: Chapter 2: Concepts in Ecosystems of British Columbia Vegetation, soil, climate
The Two Components of BEC Site Level Climate Level
The Third Component: Time Climatic Climax Shrub-herb (Pioneer) Pole-sapling (Young Seral) Young Forest (Mature Seral) Mature forest (Y. Climax) Old growth (M. Climax) Fireweed - Red raspberry Pl - Thimbleberry Pl - Western hemlock CwHw - Oak fern Seral Stage Seral plant association (common name) Site association Subhygric site in CWH zone
Ecoregion and Biogeoclimatic Ecosystem Classifications REGIONAL CLASSIFICATION ZONAL CLASSIFICATION SITE CLASSIFICATION Ecodomain Ecodivision Ecoprovince Ecoregion Ecosection Biogeoclimatic Zone Biogeoclimatic Subzone Biogeoclimatic Variant Site Association Site Series Site Type 4 Koppen climate 3 Ecozones 9 Ecoprovinces 30 Ecoregions Many Ecosections
Climate level Ecodomain uses Koppen’s classification of climate (4 climatic regions based on temperature and precipitation) Ecodivisions uses Canadian ecozones (3 divisions based on climate and physiography) Ecoprovince (10 provinces based on physiography) Ecoregion (approx. 43, equivalent to BEC zones, but more physiographically located) Biogeoclimatic zones (13 zones based on climate and vegetation)
Ecodomain: Köppen Climate Classification (Temperature, Precipitation) E=Polar T=Tropical D=Humid microthermal (rainy, snowy, cold interior) BS=Dry semi-arid microthermal (dry interior) C=humid mesothermal (coast)
Ecodivisions: Canada’s Ecozones (biomes) Based on climate and physiography
Ecoprovinces and Ecoregions: Regional Physiography Ecoprovinces in BC Coast Mountains and Islands Fraser Delta Southern Interior Plateau Central Plateau North-Central Plateau Northern Plateau Northern Plains Central Plains Columbia Mountains Columbia Highlands Ecoregion http://www.env.gov.bc.ca/ecology/ecoregions/
Ecoregion and Biogeoclimatic Ecosystem Classifications REGIONAL CLASSIFICATION ZONAL CLASSIFICATION SITE CLASSIFICATION Ecodomain Ecodivision Ecoprovince Ecoregion Ecosection Biogeoclimatic Zone Biogeoclimatic Subzone Biogeoclimatic Variant Site Association Site Series Site Type 4 Koppen climate 3 Ecozones 9 Ecoprovinces 43 Ecoregions 114 Ecosections
Biogeoclimatic Zone Definition A large geographic area with a broadly homogenous macroclimate Characterized by one or more climax tree species Named after major climax tree species http://www.for.gov.bc.ca/hre/becweb/ 7.7
Coastal Western Hemlock Mountain Hemlock Coastal Douglas-fir Alpine Tundra Bunchgrass Ponderosa Pine Interior Douglas-fir Montane Spruce Interior Cedar-Hemlock Engelmann spruce-subalpine fir Sub-boreal pine-spruce Sub-boreal Spruce Spruce-Willow-Birch Boreal White & Black Spruce
Climate Level Hierarchy Climate Classification Biogeoclimatic zone Biogeoclimatic subzone Biogeoclimatic variant Biogeoclimatic phase 7.6
Biogeoclimatic Subzone Definition A geographic area with a uniform regional climate Characterized by the same distinct climax vegetation on midslope (zonal) sites Relatively uniform mean temperature and precipitation Working level of climatic classification 7.8
Biogeoclimatic Variant Areas that are slightly drier, wetter, snowier, warmer or colder within a subzone Variants are assigned numbers Also named based on geographic area 7.9
Climate Level ‘Relief’ Diagram ESSFx ESSFx ICHx ICHx Regional Level
Biogeoclimatic Phase Accounts for variation in regional climate from local relief Helpful for management interpretations E.g., cold air ponding, calcareous soils, grasslands 7.9
Naming of Biogeoclimatic Units ZONE yz y z SUBZONE Interior Zones Coastal Zones Precipitation regime Temperature regime Continentality x = very dry (xeric) h = hot h = hypermaritime d = dry w = warm m = maritime m = moist m = mild s = submaritime w = wet k = cool v = very wet c = cold v = very cold 7.11
Landscape Profile 6.1
Zonal Site The site that best reflects the regional climate Characteristics flat to moderate slopes middle slope positions that neither shed nor receive an excess of water and nutrients (inputs balance outputs) medium soil texture (loam) medium nutrient regime moderately well-drained soils no root restricting layers 5.2
Relationship Between a Zonal Site and the Climate Level of BEC Climate Classification Biogeoclimatic zone Biogeoclimatic subzone Zonal Site Biogeoclimatic variant Biogeoclimatic phase
The effect of regional climate & relief on BEC variants Kamloops Forest Region S N aspect
Identifying BEC variants using key Kamloops Forest Region
Differentiated table for lower elevation coastal subzones and variants
Hw Hw-flat moss CWHdm/01 (medium, zonal) Coniferous forest Coastal coniferous forest Coastal Western Hemlock forest Dry Maritime CWH forest Hw Hw-flat moss CWHdm/01 (medium, zonal)
Site Level Hierarchy Site Classification Site association Site series Site phase 7.15
Site Series Definition All sites capable of producing the same mature or climax plant communities within a biogeoclimatic subzone or variant Most commonly used category for field use 7.16
Edatopic Grid 6.8
Edatopic Grid Relative soil moisture regime classes 6.8
Edatopic Grid Relationship between site properties and soil nutrient regime classes
Site Series CWHdm=subzone=plant association CHHdm/01=site series=plant subassociation
Naming of Site Units ICHmw2 /01 Biogeoclimatic unit Site series HwCw - Falsebox - Feathermoss
Site Level Hierarchy Site Classification Site association Site series Site phase
Site Association Definition All sites capable of producing similar near climax vegetation in one or more biogeoclimatic units More variable that site series; therefore less predictable for management application eg. HwCw - Falsebox - Feathermoss
Site Association, example Pl=lodgepole pine Fd=Douglas-fir Hw=western hemlock Cw=western redcedar Ss=Sitka spruce Yc=Alaska yellow cedar Site Association, example Subzone: annual precipitation CHWdm CWHmm CHWwh Xeric Fd, Pl Hw, Fd Hw, Cw Mesic Ss, Hw, Cw Hygric Cw, Yc Site: absolute soil moisture regime
Site Phase Definition Subdivides site series based on criteria which might be important for management interpretations, such as coarse and fine textured soils, etc.