73a 73d 73j 73h 73d 73d 73d 73d 73j 73h 35c 35b 35c 35a 73i 73i 73i 73i 73i 73i 35c 35c 35c 35a 35g 35g 35a 35a 35b 73h 35c 73a 35e 73d 73j 35b 35a 73d 73d 35c 35c 35e 35c 35c 35c 35a 35b 35c 73i 35c 35c 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 73m 73m 73m 75a 74d 34a 34j 75i 35b 73n 73n 73o 73o 73o 73o 34a 34g 34g 73n 73n 73n 73n 73n 73n 73o 73n 73o 73o 73o 73o 73 35 35 73 73 65 74 75 75k 34 35 73m 35b 35b 35f 35b 65p 65 73i 73k Baton Rouge Jackson Abbeville Alexandria Amite Bastrop Bay Saint Louis Cameron Canton Covington Crowley DeRidder Morgan City Gulfport Hattiesburg Houma Jasper Jennings Lafayette Lake 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 Ville Platte 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 Lake Pontchartrain Lake Maurepas Lake Borgne White Lake Grand Lake Calcasieu Lake Sabine Lake CHANDELEUR SOUND BRETON SOUND M I S SISSIPPI S O U N D P e a r l R i v e r Lake Salvador M i s s i s s i p p i R i v e r ATCHAFALAYA BAY VERMILION BAY WEST COTE BLANCHE BAY Cocodrie Lake Catahoula Lake R e d R i v e r Bayou D’Arbonne Lake A tc h a f a l a ya R i v er Y a z o o R i v e r M i s s i s s i p p i R i v e r S a b i n e R i v e r R e d R iv e r Toledo Bend Reservoir Cross Lake Caddo Lake Lake Bistineau Lake Claiborne Lake Iatt Vernon Lake C a l c a s i e u R iv e r B o g u e C h i tto A m i t e R i v e r R i v e r D u g d e m on a L i t t l e R i v e r Castor C r e e k O u a c h i t a B a y o u B a rth o l o m e w Re d R i v e r B l a c k R i v e r T e n s as R i v e r B o e u f Ri v e r B a y ou D o r c h e a t B o d c a u B a y o u B l a c k L a k e B a y o u S a l i n e B a yo u H o u s t o n R i v e r B i g B l a c k R i v e r EAST COTE BLANCHE BAY TERREBONNE BAY TIMBALIER BAY BARATARIA BAY La f o u r c h e B a y o u B a y o u Te c h e T a n g ip a h o a R i v e r R i v er C o m it e M e r m e n t au R . B a y o u N e z p i q u e B a y o u P l a q u e m i n e B r u l e B a y o u d e s C a n n e s B a y o u A n a c o c o Lake Jack Lee R i v e r Caney Creek Reservoir O u a c h i t a R i v e r B a y o u M a c o n Lac des Allemands CAILLOU BAY MARSH ISLAND POINT AU FER ISLAND I S L E S D E R NI E R E S C H A N D E L E U R I S L A N D S ARKANSAS TEXAS TEXAS 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 Projection Standard Parallels 30˚ N and 32˚ N 15 30 mi 0 30 60 km 0 5 10 15 10 20 30 Level III ecoregion Level IV ecoregion Parish boundary State boundary 34 Western Gulf Coastal Plain 34a Northern Humid Gulf Coastal Prairies 34c Floodplains and Low Terraces 34g Texas-Louisiana Coastal Marshes 34j Lafayette Loess Plains 35 South Central Plains 35a Tertiary Uplands 35b Floodplains and Low Terraces 35c Pleistocene Fluvial Terraces 35e Southern Tertiary Uplands 35f Flatwoods 35g Red River Bottomlands 65 Southeastern Plains 65f Southern Pine Plains and Hills 65p Southeastern Floodplains and Low Terraces 73 Mississippi Alluvial Plain 73a Northern Holocene Meander Belts 73d Northern Backswamps 73h Arkansas/Ouachita River Holocene Meander Belts 73i Arkansas/Ouachita River Backswamps 73j Macon Ridge 73k Southern Holocene Meander Belts 73l Southern Pleistocene Valley Trains 73m Southern Backswamps 73n Inland Swamps 73o Deltaic Coastal Marshes and Barrier Islands 74 Mississippi Valley Loess Plains 74a Bluff Hills 74c Southern Rolling Plains 74d Baton Rouge Terrace 75 Southern Coastal Plain 75a Gulf Coast Flatwoods 75i 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. Ecoregions of Louisiana LA_eco_06fnl.ai 06/12/06