Ecoregions of North America-Level II (CEC)

Published: April 15, 2008, 7:19 pm

Topics:

Ecology (main) Geography (main)

The 52 level II ecological regions that have been delineated are intended to provide a more detailed description of the large ecological areas nested within the Level I regions (Ecoregions of North America-Level II (CEC)). For example, the Tropical Humid Forests of level I is the region covering coastal portions of the United States and Mexico, and is composed of six level II regions. Level II ecological regions are useful for national and subcontinental overviews of physiography, wildlife, and land use.

Three level I regions (Hudson Plains, Marine West Coast Forests and Mediterranean California) have no level II delineations. The Great Plains, Tropical Dry Forests and Tropical Humid Forests level I regions, on the other hand, each have six level II subdivisions. The table below provides a synopsis of the major physical and biological attributes along with human activities associated with each of the level II ecological regions.

Level II ecoregions are characterized as follows:

• number of ecological regions: 52
• scale of presentation: 1:30 million
• nested within level I regions
• national/regional perspectives
• determination of the areas composing the regions through satellite imagery and appropriate natural resource source maps at broad scales (approximately 1:20 million – 1:30 million)

ECOLOGICAL REGIONS OF NORTH AMERICA
Level I	Landforms; Water Bodies	Surface materials; Soils	Climate (mean annual temperature; mean annual precipitation)	Vegetation	Wildlife	Human activities
Level II Surface (km2)
1 ARCTIC CORDILLERA 218,225
1.1 Arctic Cordillera 218,225	mountains, glaciers and icefields	largely ice and bedrock; some frozen soils	-20°C to –6°C 200-600 mm	soma Arctic tundra in valleys and at sea level	wide occurrence of ice fields restricts wildlife habitat and species diversity	sparsely settled area; some recreational use and subsistence hunting
2 TUNDRA 2,856,850
2.1 Northern Arctic 1,495,255	hills and plains; some lakes	moraines and some bedrock; frozen soils, continuous permafrost	-17°C to –11°C 100-200 mm	discontinuous Arctic tundra, e.g., ground-hugging shrubs, herbs and lichens	Peary caribou, polar bear, musk ox, snow geese	very low intensity hunting and trapping; oil and gas activities and isolated mining
2.2 Alaska Tundra 390,490	coastal plain and some hills; some lakes and small ponds	moraines, bogs and fens, marine deposits; frozen soils and permafrost	-13°C to –7°C 100-300 mm	continuous Arctic tundra, low shrubs	Grant's caribou, Richardson's ground squirrel	oil and gas; low intensity subsistence hunting and trapping
2.3 Brooks Range Tundra 162,835	mountains and some valleys	colluvium, bedrock and moraines; frozen soils and permafrost	-13°C to –7°C 150-300 mm	discontinuous alpine tundra	barren ground caribou	low intensity hunting and trapping
2.4 Southern Arctic 808,270	rolling hills and plains; numerous lakes	moraines and some exposed bedrock: frozen soils and permafrost	-11°C to –7°C 200-500 mm	Arctic low to medium shrubs	barren ground caribou, Arctic fox, Arctic ground squirrel, ptarmigan	hunting and trapping; mineral exploration
3 TAIGA 2,799,230
3.1 Alaska Boreal Interior 459,780	plains and some hills	moraines, bogs and fens; frozen soils and permafrost, some forest soils	-9°C to –1°C 200-500 mm	medium to high Arctic shrubs, open coniferous forest	caribou, moose, black bear, wolf	low intensity hunting and trapping: some tourism; locally commercial forestry
3.2 Taiga Cordillera 223,870	mountains and narrow valleys	colluvium, moraines, and rock; primarily frozen soils and some weakly-developed acidic forest soils	-10°C to –5°C 300-700 mm	medium to high alpine shrubs, open coniferous forests	Dall sheep, caribou, black and grizzly bear, wolf, gyrfalcon	low intensity hunting and trapping; tourism; some mineral exploration
3.3 Taiga Plains 701,625	plains; some lakes	moraines, bogs, lacustrine and some alluvium; primarily frozen soils with some wet soils and organics	-10°C to –1°C 200-500 mm	Arctic tundra meadow and wetland associations, open conifer stands	moose, caribou, black bear, wolf	low intensity hunting, trapping and fishing; oil and gas extraction; some tourism
3.4 Taiga Shield 1,413,955	hills and some plains; numerous small lakes	bedrock and moraines; primarily some nutrient-poor acidic forest soils	-8°C to –1°C 200-800 mm	open shrubs and sedge meadows, open conifer forest	moose, caribou, black bear, wolf, snowshoe hare, waterfowl (black ducks)	low intensity hunting, trapping and fishing; mineral exploration; some tourism
4 HUDSON PLAINS 334,530
4.1 Hudson Plains 334,530	coastal plains and wetlands	marine deposits, bogs and fens; frozen organic soils and nutrient-poor acidic forest soils	-4°C to –2°C 400-800 mm	Arctic tundra and boreal forest transition	some moose, caribou, black bear and polar bear, well known for waterfowl habitat	low intensity subsistence hunting, trapping and fishing; limited sport tourism
5 NORTHERN FORESTS 2,363l,825
5.1 Softwood Shield 1,427,115	hills with some plains; numerous lakes	bedrock interspersed with moraines and some fluvium; nutrient-poor forest soils	-2°C to –6°C 550-1,500 mm	primarily conifers (white and black spruce, balsam fir, jack pine), lichens and shrubs	woodland caribou, white-failed deer, moose, beaver, black bear, lynx, great horned owl	forestry, hydropower, mining; tourism subsistence and commercial hunting, trapping and fishing
5.2 Mixedwood Shield 569,245	Plains with some hills; numerous lakes and wetlands	bedrock interspersed with moraines and some fluvium and lacustrine; nutrient-poor, leached forest soils with pockets of fine textured soils	1°C to 9°C 500-1,200 mm	mixedwoods: conifers (white and black spruce, balsam fir, jack pine), balsarn poplar, oak, sugar maple and beech	white-tailed deer, racoon, skunk, wolf	forestry; local mining; tourism
5.3 Atlantic Highlands 367,465	hills and some plains	soma bedrock interspersed with moraines and marine deposits; nutrient-poor, leached forest soils with pockets of fine- textured soils	4°C to 9°C 900-1,500 mm	wide range of mixedwoods, including hemlock, balsam air, red and white pine, sugar maple, red spruce	white-tailed deer, moose, black bear, skunk, eastern gray squirrel, eastern bluebird	forestry; local agriculture; local mining; Borne fishing; major tourism
6 NORTHWESTERN FORESTED MOUNTAINS 1,788,950
6.1 Boreal Cordillera 647,830	high mountains and some wide valleys	mountains and some colluviurn; nutrient-pour forest soils	-10°C to -5°C 300-700 mm	boreal forest (black and white spruce, lodgepole pine) and some alpine vegetation	woodland caribou, Dall sheep and small furbearers	mining, forestry; commercial trapping; local tourism
6.2 Western Cordillera 1,141,120	high mountains and some wide valleys	bedrock, colluvium and moraines; nutrient-poor forest soils	1°C to 10°C 700-3,000 mm	alpine to conifer forest (subalpine fir, Douglas fir, ponderosa pine) to semi-arid shrubs and grassland	mule deer, elk, black bear, bighorn sheep, cougar, Steller's jay	forestry; grazing; tourism
7 MARINE WEST COAST FORESTS 2,548,435
7.1 Marine West Coast Forests 692,970	high and low mountains with some hills and valleys	bedrock, colluvium and moraines; nutrient-poor forest soils	5°C to 12°C 600- 6,000 mm	alpine to temperate rainforests (western red cedar, western hemlock, Sitka spruce, Douglas fir, redwood)	grizzly bear, black bear, elk, black-tailed deer, shrew mole, golden eagle, blue heron. blue jay, salmon	intensive forestry; tourism; fishing; local urbanization and agriculture
8 EASTERN TEMPERATE FORESTS 2,578,435
8.1 Mixedwood Plains 490,590	mainly plains, some hills, many small lakes	moraines and lacustrine; forest soils, fine textured soils	4°C to 10°C 720-1,200 mm	oak, hickory, maple, beech. and some pine and basswood	white-tailed deer, moose, gray squirrel	major urban areas; agriculture (dairy, fruit); some forestry and tourism
8.2 Central USA Plains 253,665	smooth plains	moraines with some lacustrine; calcium-enriched prairie soils, forest soils on moraine	7°C to 13°C 760-1,100 mm	formerly oak, hickory, elm, ash, beech, maple with more prairie to the west	white-tailed deer cottontail rabbit, gray squirrel	agriculture (major corn and soybean area), locally important dairy area; major urban areas
8.3 Southeastern USA Plains 946,770	irregular plains, low hills	residuum and some loess; weakly developed soils	13°C to 19°C 1,000-1,600 mm	oak, hickory, loblolly and shortleaf pine	white-tailed deer, gray squirrel, armadillo, wild turkey, northern cardinal, mockingbird	forestry; agriculture (tobacco, hogs, cotton); urban areas
8.4 Ozark and Ouachita- Appalachian Forests 518,690	hills and low mountains, some wild valleys	residuum and colluvium; weakly developed soils	17°C to 18°C 1,000-2,000 mm	mixed oaks with hickory, also white pine, birch, beech, maple, hemlock	black bear, white-tailed deer, chipmunk, wild turkey	forestry; coal mining; some local agriculture; tourism
8.5 Mississippi Alluvial and soutbeastern Coastal Plains 368,720	flat plains; many wetlands	alluvium and coastal marine deposits; fine-to medium-textured forest soils, organics	13°C to 27°C 1,100-1,800 mm	bottomland [[forest]s] (ash, oak, tupelo, baldcypress); southern mixed forests (beech, sweet gum, magnolias, oaks, pine, saw palmetto)	white-tailed deer, opossum, armadillo, American alligator, mockingbird, egret	forestry and agriculture (citrus, soybeans, cotton); tourism; fishing
9 GREAT PLAINS 3,543,875
9.1 Boreal Plains 644,560	plains	moraines and lacustrine; nutrient-poor acidic soils	-2°C to 2°C 300-625 mm	trembling aspen with black arid white spruce, balsam fir	woodland caribou, beaver, wolf, coyote, red fox	forestry and agriculture with some oil and gas industry; hunting and recreation
9.2 Temperate Prairies 785,400	mainly irregular plains, flatter to the northwest; numerous small lakes and wetlands	moraines with some loess in the south, some lacustrine; mainly calcareous soils	2°C to 13°C 400-1,000 mm	formerly tall grass/aspen parkland, currently cropland	white-tailed deer, waterfowl, pheasant, meadowlark	agriculture (cereal grain, livestock, feedlots)
9.3 West-Central Semi-Arid Prairies 911,425	irregular plains, table- lands and low hills	moraines and lacustrine in the north; residuum, alluvium, and eolian; sand deposits in the south, prairie soils	2°C to 8°C 250-650 mm	formerly native short grass prairie (wheat grass, porcupine grass), currently cropland	pronghorn antelope, jackrabbit, black-tailed prairie dog, mule deer, sage grouse, magpie	agriculture (cattle and sheep grazing, wheat, barley, hay)
9.4 South-Central Semi-Add Prairies 1,003,375	smooth and irregular plains, and tablelands	alluvium, loess and residuum; calcareous soils	7°C to 21°C 250-750 mm	short grass prairie in the north and grasslands with mesquite, juniper, and oak in the south	jackrabbit, white-tailed deer, armadillo, mourning dove, magpie, vulture	agriculture (sorghum. wheat, cattle feedlots, goats, sheep
9.5 Texas-Louisiana [[Coast]al] Plain 64,615	flat plains arid some barrier islands	alluvium and wetlands; calcareous soils, some rich in organics	18°C to 25°C 750-1,300 mm	southern cord grass/bluestern grass area; much of this is currently in agriculture	alligator, armadillo, rattlesnakes, ducks, pelican, plover, sandpiper	petrochemical industry; agriculture (rice, sorghum, cattle pasture); fishing; tourism
9.6 Tamaulipas-Texas Semi-Arid Plain 134,500	plains end low hills	alluvium; saline, fine-textured soils	22°C to 26°C 300-400 mm	thorn shrubs as lotebrush, granjeno, mesquite, gavia, cenizo, halophilous vegetation near the coast	black bear, cougar, Texas white-tailed deer, collared peccary, beaver, eastern mole, Berlandier's tortoise, rock rattlesnake, Mexican duck, blue-winged teal, white-winged dove	agriculture (corn, cartamus, sunflower, beans, sorghum), grazing; manufacturing; tourism
10 NORTH AMERICAN DESERTS 2,027,460
10.1 Western Interior Basins and Ranges 1,014,840	plains with low and high mountains and some tablelands	colluvium, alluvium, bedrock, some loess; dry calcareous soils	2°C to 16°C 150-1,200 mm	sagebrush, shadscale, greasewood, juniper, Mexican piñon, invasive cheatgrass and several other tufted grasses	mule deer in mountains, pronghorn antelope, sage grouse, magpie	some agriculture in the north, grazing; local mining; tourism
10.2 Sonoran and Mohave Deserts 398,120	plains with low mountains	alluvium and bedrock; shallow, saline soils	13°C to 24°C 50-250 mm	creosote bush, burro sage, paloverde, ocotillo, saguaro, joshua tree	Sonora, pronghorn antelope, mule deer, bighorn sheep, antelope jackrabbit, desert tortoise, horned rattlesnake, Gila monster, bald eagle, Mexican falcon, greater roadrunner, Gambel's quail, scaled quail	local agriculture (vegetables, dates, citrus fruits) under irrigation; urban areas; industry, mining
10.3 Baja Californian Desert 103,935	plains with low hills and mountains	bedrock and colluvium; shallow, saline soils	10°C to 20°C <300 mm	many endemic species: cirio, copalquín, elephant tree, cardón, Adam tree, agaves, cholla, and abundant tufted lichens	Peninsular pronghorn antelope, bighorn sheep, ring-tailed cat, Baja California rock squirrel, red diamondback rattlesnake, Baja California rattlesnake, golden eagle, osprey, California quail	agriculture under irrigation. grazing; salt mining; tourism national parks, protected areas
10.4 Chihuahuan Desert 5l0,565	plains with low mountains, some high mountains	colluvium and some bedrock- saline desert soils	10°C to 18°C 100-600 mm	tarbush, creosote, yucca, lechuguilla, prickly pear, tobosa end grama grasses	mule deer, bighorn sheep, coyote, black-tailed jackrabbit, Mexican prairie dog, bolson tortoise, desert tortoise, Mexican alligator lizard, rattlesnakes, scaled quail, burrowing owl	low intensely land use overall, local vegetable and cotton, grazing; mining, industry; urban areas
11 MEDITERRANEAN CALIFORNIA 198,975
11.1 Mediterranean California 198,975	flat plains, plains with low mountains, some high mountains	colluviurn and alluvium; bedrock; calcareous soils to weakly developed, neutral forest soils	7°C to 25°C 250-1,000 mm	central valley was formerly grasslands; oak woodlands, chaparral, chamiso, coastal sagebrush, pine forest	mule deer, black-tailed deer, coyote kit fox, jackrabbit, southern sea otter, Lewis woodpecker	Mediterranean-type agriculture (fruits/ vegetables/dairy); urban areas: oil and gas, industry; recreation and tourism
12 SOUTHERN SEMI-ARID HIGHLANDS 270,340
12.1 Western Sierra Madre Piedmont 194,945	piedmont, hills and plains	colluvium and bedrock; calcareous, weakly developed neutral soils	10°C to 18°C 600-1,000 mm	shrub and grasses to Mexican piñon and ponderosa pine, oak, juniper	coyote, badger, (striped) skunk, white- sided jackrabbit, spotted ground squirrel, bullsnake, northern harrier, white-winged dove, band-tailed pigeon	range grazing and agriculture
12.2 Mexican High Plateau 75,395	high elevation plains and hills	colluvium and alluvium; coarse and clayey soils	10°C to 18°C 300-600 mm	mesquite, dryland shrubs and grasses	kit fox, white-sided jackrabbit, spotted ground squirrel, red-tailed hawk	agriculture and range grazing; industry; tourism
13 TEMPERATE SIERRAS 630,045
13.1 Upper Gila Mountains 105,255	low and high mountains	colluvium end bedrock; calcareous, weakly developed soils	0°C to 13°C 400-850 mm	ponderosa pine/white fir forest at higher elevations; lower elevations have Oak, juniper, Mexican piñon and chaparral	mule deer, porcupine, red squirrel, red-faced warbler, yellow-eyed junco, Steller's jay, red-tailed hawk	some forestry at upper elevations; recreation; grazing
13.2 Western Sierra Madre 203,625	volcanic mountains	colluvium and alluvium; coarse and clayey soils	10°C to 18°C 600-1,500 mm	conifer and oak [[forest]s] (pine, piñon, fir, spruce, oaks, madrone)	cougar, timber wolf, white-tailed deer, gray fox, coati, Arizona ridge-nosed rattlesnake, golden eagle, wild turkey, thick-billed parrot. eared trogon	forestry; extensive grazing (cattle and sheep)
13.3 Eastern Sierra Madre 58,105	sedimentary mountains	colluvium; shallow soils	10°C to 18°C 600-3.000 mm	conifer and oak forests, cloud forests, red pine, sweet gum, oak, alder, walnut	black bear, bobcat, white-tailed deer, cottontail rabbit, arboreal alligator lizard, peregrine falcon, maroon-fronted parrot, wild turkey	forestry; agriculture, coffee plantations
13.4 Transversal Neovolcanic System 118,795	volcanic mountains arid plains	alluvium and colluvium: volcanic and clayey soils	10°C to 18°C 1,000-2,000 mm	conifer and oak forests (pine, fit, white cedar, oak, madrone black cherry, Mexican hawthorn)	badger, long-tailed weasel, volcano rabbit, Mexican alligator lizard, axolotl, black-tailed rattlesnake, Mexican pygmy rattlesnake. black-crowned night-heron, long-tailed wood partridge	forestry; agriculture, extensive grazing (cattle and sheep); main industrial area; nearly 40% of Mexican population lives here
13.5 Southern Sierra Madre 118,025	geologically complex mountains	colluvium and alluvium; shallow soils and clayey soils	10°C to 26°C 1,000-3,000 mm	conifer end oak forests; cloud forests, pin, oak, fir, árbol de las manitas	West Mexican chachalaca, neotropical otter, Mexican woodnymph	forestry; agriculture (plantations and traditional); tourism
13.6 Central American Sierra Madre and Chiapas Highlands 26,240	granitic and sedimentary mountains	residuum and colluvium; deep clayey soils	18°C to 22°C 2,000-4,000 mm	conifer and oak [[forest]s]; cloud forests (pine, oak, sweet gum)	red-lipped alligator lizard, horned guan, quetzal, white-breasted haw)	forestry; tourism; coffee plantations
14 TROPICAL DRY FORESTS 246,260
14.1 Gulf of Mexico Dry [[Coast]al] Plains end Hills 33,885	plains and hills	colluviumn and alluvium; clayey and calcareous soils	24°C to 26°C 600-800 mm	deciduous and thorn forests (Texas ebony, cerón, copal rnesquite)	jaguar, chachalaca, wild turkey, green parakeet, red-crowned parrot	extensive grazing, agriculture
14.2 Northwestern Plain of the Yucatán Peninsula 14,165	Karst plain, wetlands	colluvium and alluvium; calcareous soils	24°C to 28°C 600-800 mm	deciduous forests (gummo-limbo, cordia/canalete, tepeguaje, angelica tree)	paca, hog-nosed Skunk, black-throated bobwhite, lesser roadrunner	henequén plantations; tourism
14.3 Western Coastal Plain, Hills and Canyons 84,225	plains, canyons and hills	alluvium and colluvium; clayey and calcareous soils	24°C to 26°C 500-600 mm	deciduous forest (gum bumelia, camachile, tepeguaje, copale, ceiba)	neotropical otter, green iguana, bald eagle, northern goshawk, San Blas jay, military macaw	traditional and commercial agriculture, grazing
14.4 lnterior Depressions 64,900	depression	alluvium and bedrock; shallow soils	24°C to 28°C 400-800 mm	deciduous and thorn forests (copale, cuajiote, leadtree, tepeguaje. lemonwood); xeric shrubland	tropical ground squirrel, ring-tailed cat, black iguana, beaded lizard, balsas screech owl	commercial agriculture (irrigation) ,traditional agriculture, grazing
14.5 Southern Pacific Coastal Plain and Hills 39,915	plains and hills	alluvium and bedrock; shallow soils	22°C to 26°C 600-1,000 mm	deciduous forest (copale, ceiba, bonete, amole, cordia, camachile)	ring-tailed ground squirrel, green iguana, American crocodile, boa, ornate cantil, West Mexican chachalaca	commercial agriculture plantations; tourism
14.6 Sierra and Plains of El Cabo 9,170	hills and plains	alluvium; shallow, weakly developed soils	22°C to 24°C 600-1,000 mm	deciduous forest (mesquite, huisache, elephant tree, hog plum, palo de arco) oak/pine forest on summits	mule deer, cape shrew, San Lucan gecko, Pacific water snake. Baja California whiptail, cape pygmy owl	tourism
15 TROPICAL HUMID FORESTS 311,120
15.1 Gulf of Mexico Humid Coastal Plains and Hills 141,390	coastal plains and hills, wetlands	alluvium and colluvium; poorly-drained and clayey soils	22°C to 24°C 2,000-4,000 mm	tall and medium-height evergreen forests (paque, allspice tree, palms, sombrerete, breadnut, copai-yé wood, mahogany, mangrove, forbes)	tapir, white-lipped peccary, spider monkey, vampire bat, Morelet's crocodile, green iguana, fer de lance, Muscovy duck, scarlet macaw, happy eagle, keel-billed toucan	extensive grazing, agricultural plantations; petroleum industry; tourism

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Citation

Cooperation, C. (2008). Ecoregions of North America-Level II (CEC). Retrieved from http://editors.eol.org/eoearth/wiki/Ecoregions_of_North_America-Level_II_(CEC)