73a

73d

73j

73h

73d

73d

73d

73d

73j

73h

35c35b

35c

35a

73i

73i

73i73i

73i

73i

35c

35c

35c

35a

35g

35g

35a

35a35b

73h

35c

73a

35e

73d

73j

35b

35a

73d

73d

35c

35c

35e

35c

35c

35c

35a

35b

35c

73i

35c35c

73k

73k

73k

73k

73k

73m

73m

35c

73m

35c

35e

73m

73l

73l

35c

35c

35b

65p

65f

73m

74a

73m

34c

34c

73m

74c

73k

35f

73m

73m

73m73m

73m

75a

74d

34a

34j

75i

35b

73n

73n

73o

73o

73o73o

34a

34g

34g73n

73n

73n

73n

73n

73n73o

73n

73o

73o

73o

73o

7335

35

73

73

65

74

75

75k

34

35

73m

35b

35b

35f

35b

65p

65

73i

73k

BatonRouge

Jackson

Abbeville

Alexandria

Amite

Bastrop

Bay Saint Louis

Cameron

Canton

Covington

Crowley

DeRidder

Morgan City

Gulfport

Hattiesburg

Houma

Jasper

Jennings LafayetteLake Charles

Lake Providence

Laurel

Leesville

Hammond

McComb

Mansfield

Marksville

Minden

Monroe

Natchez

Natchitoches

New Iberia New Orleans

New Roads

Opelousas

Beaumont

Philadelphia

Plaquemine

Port Allen

Ruston

Saint Francisville

Shreveport

Tallulah

Thibodaux

Vicksburg

VillePlatte

Winnfield

Winnsboro

Yazoo City

Eunice

Bogalusa

Biloxi

Slidell

Grand Isle

Crossett

Port Arthur

Oakdale

G U L F O F M E X I C O

LakePontchartrain

LakeMaurepas

LakeBorgne

White Lake

Grand LakeC

alca

sieu

Lak

e

SabineLake

CHANDELEUR SOUND

BRETON SOUND

MISSISSIPPI SOUND

Pearl Riv

er

LakeSalvador

Mississi pp i River

ATCHAFALAYA BAY

VERMILIONBAY WEST COTE

BLANCHE BAY

CocodrieLake

Catahoula Lake

Red Ri ver

Bayou D’Arbonne Lake

Atch

a falaya R

iver

Ya

zo o

Ri

ver

Miss

i s

sip

piRi

ver

Sabi

ne

Riv

er

Red River

Toledo BendReservoir

CrossLake

CaddoLake

LakeBistineau

LakeClaiborne

Lake Iatt

VernonLake

Calcasie

u

River

Bogue Chitto

Am

ite R

iver

River

Dugdemona

Little River

Castor Creek

Ouachita

B ayou

Bartholomew

Re d R iver

Bla

ck River

T e nsas

Riv

er

Boe

uf

River

Ba

you

Dor

ch

eat

Bodcau B

ayou

Bla

ck Lake B

ayou

Sa

l ine Bayou

Houston River

B i g

Bla c k Ri v

er

EAST COTE

BLANCHE BAY

TERREBONNEBAY

TIMBALIERBAY

BARATARIABAY

Lafourche

Ba you

Bayou

Teche

Tangipahoa

River

Ri ver

Co

mite

Merm

enta

u R.

Bay

ouN

ezp

ique

Bayou Plaq

uem

ine B

r ule

Bayo

u de

s Canne

s

Bayou A

nacoc

o

LakeJack Lee

River

Caney CreekReservoir

Ouachita River

Bay

ou M

acon

Lac desAllemands

CAILLOU BAY

MARSH ISLAND

POINTAU FERISLAND

ISLES DERNIERES

C

HA

ND

EL

EU

R

I S

LA

ND

S

ARKANSAS

TE

XA

S

TEX

AS

MISSISSIPPI

94˚ 93˚ 92˚ 91˚ 90˚ 89˚

94˚ 93˚ 92˚ 91˚ 90˚ 89˚

29˚

30˚

31˚

32˚

33˚

29˚

30˚

31˚

32˚

33˚

SCALE 1:1 000 000

Albers Equal Area ProjectionStandard Parallels 30˚ N and 32˚ N

15 30 mi0

30 60 km0

51015

102030

Level III ecoregionLevel IV ecoregionParish boundaryState boundary

34 Western Gulf Coastal Plain34a Northern Humid Gulf Coastal Prairies34c Floodplains and Low Terraces34g Texas-Louisiana Coastal Marshes34j Lafayette Loess Plains

35 South Central Plains35a Tertiary Uplands35b Floodplains and Low Terraces35c Pleistocene Fluvial Terraces35e Southern Tertiary Uplands35f Flatwoods35g Red River Bottomlands

65 Southeastern Plains65f Southern Pine Plains and Hills65p Southeastern Floodplains and Low Terraces

73 Mississippi Alluvial Plain73a Northern Holocene Meander Belts73d Northern Backswamps73h Arkansas/Ouachita River Holocene Meander Belts73i Arkansas/Ouachita River Backswamps73j Macon Ridge73k Southern Holocene Meander Belts73l Southern Pleistocene Valley Trains73mSouthern Backswamps73n Inland Swamps73o Deltaic Coastal Marshes and Barrier Islands

74 Mississippi Valley Loess Plains74a Bluff Hills74c Southern Rolling Plains74d Baton Rouge Terrace

75 Southern Coastal Plain75a Gulf Coast Flatwoods75i Floodplains and Low Terraces 75k Gulf Barrier Islands and Coastal Marshes

PRINCIPAL AUTHORS: Jerry J. Daigle (NRCS), Glenn E. Griffith (Dynamac Corporation), James M. Omernik (USGS), Patricia L. Faulkner (LNHP-LDWF), Richard P. McCulloh (LGS), Lawrence R. Handley (USGS-National Wetlands Research Center [NWRC]), Latimore M. Smith (The Nature Conservancy), and Shannen S. Chapman (Dynamac Corporation).

COLLABORATORS AND CONTRIBUTORS: Bradley Spicer (LDAF), Sue Smith (LDEQ), Paul Heinrich (LGS), John Novosad (USFS), Bill Vermillion (USFWS), Charles Demas (USGS), Dennis Demcheck (USGS), C. Edward Proffitt (USGS-NWRC), Philip Crocker (USEPA), Barbara Kleiss (USACE, ERDC-Waterways Experiment Station), Jan Boydston (LDEQ), Alan Woods (Oregon State University), Pat O'Neil (USGS), Brian Moran (Indus Corporation), John Hutchinson (Science Applications International Corporation), Jack Wittmann (USGS), and Tom Loveland (USGS).

REVIEWERS: Martin Floyd (NRCS), Anthony Lewis (Louisiana State University), and Chris Reid (LNHP-LDWF).

CITING THIS MAP: Daigle, J.J., Griffith, G.E., Omernik, J.M., Faulkner, P.L., McCulloh, R.P., Handley, L.R., Smith, L.M., and Chapman, S.S., 2006, Ecoregions of Louisiana (color poster with map, descriptive text, summary tables, and photographs): Reston, Virginia, U.S. Geological Survey (map scale 1:1,000,000).

Electronic versions of ecoregion maps and posters as well as other ecoregion resources are available at http://www.epa.gov/wed/pages/ecoregions.htm.

Ecoregions denote areas of general similarity in ecosystems and in the type, quality, and quantity of environmental resources. They are designed to serve as a spatial framework for the research, assessment, management, and monitoring of ecosystems and ecosystem components. By recognizing the spatial differences in the capacities and potentials of ecosystems, ecoregions stratify the environment by its probable response to disturbance.

Ecoregions are general purpose regions that are critical for structuring and implementing ecosystem management strategies across federal agencies, state agencies, and nongovernment organizations responsible for different types of resources in the same geographical areas. The approach used to compile the ecoregion map of Louisiana is based on the premise that ecological regions can be identified through the analysis of the spatial patterns and the composition of biotic and abiotic characteristics that affect or reflect differences in ecosystem quality and integrity. These characteristics include geology, physiography, vegetation, climate, soils, land use, wildlife, and hydrology. The relative importance of each characteristic varies from one ecological region to another regardless of ecoregion hierarchical level.

Louisiana contains barrier islands and coastal lowlands, large river floodplains, rolling and hilly coastal plains with evergreen and deciduous forests, and a variety of aquatic habitats. There are 6 level III ecoregions and 28 level IV ecoregions, and most of these continue into ecologically similar parts of adjacent states.

This ecoregion map was compiled at a scale of 1:250,000, and depicts revisions and subdivisions of earlier level III ecoregions that were originally compiled at a smaller scale. It is part of a collaborative project primarily between USEPA–National Health and Environmental Effects Research Laboratory (Corvallis, Oregon), U.S. Geological Survey (USGS), U.S. Department of Agriculture–Natural Resources Conservation Service (NRCS), Louisiana Natural Heritage Program (LNHP) within the Louisiana Department of Wildlife and Fisheries (LDWF), Louisiana Geological Survey (LGS), and Louisiana Department of Environmental Quality (LDEQ). Collaboration and consultation also occurred with the Louisiana Department of Agriculture and Forestry (LDAF), Louisiana Department of Natural Resources, U.S. Department of Agriculture–Forest Service (USFS), U.S. Army Corps of Engineers (USACE), U.S. Fish and Wildlife Service (USFWS), and USGS–Center for Earth Resources Observation and Science. This project is associated with an interagency effort to develop a common framework of ecological regions. Reaching that objective requires recognition of the differences in the conceptual approaches and mapping methodologies applied to develop the most common ecoregion-type frameworks, including those developed by the USFS, the USEPA, and the NRCS. As each of these frameworks is further refined, their differences are becoming less discernible. Each collaborative ecoregion project, such as this one in Louisiana, is a step toward attaining consensus and consistency in ecoregion frameworks for the entire nation.

E c o r e g i o n s o f L o u i s i a n a

LA_eco_06fnl.ai 06/12/06