Louisiana: The History of an American State Chapter 2 Louisiana’s Geography: Rivers and Regions Study Presentation ©2005 Clairmont Press

Louisiana: The History of an American State Section 1: Louisiana’s Location Section 2: Louisiana’s Waterways Section 3: Louisiana’s Natural Regions Section 4: Louisiana’s Climate Section 5: People and the Environment

Section 1: Louisiana’s Location ESSENTIAL QUESTION: What are the differences between absolute and relative location, and what are Louisiana’s boundaries?

Section 1: Louisiana’s Location What words do I need to know? absolute location relative location latitude longitude prime meridian cartographer

Section 1: Louisiana’s Location Louisiana in the United States Boundaries

Louisiana in the United States Louisiana: between 28° 55 ́ & 33° north (N) latitude & between 89° & 92° west (W) longitude North Africa, the Middle East, & the Indian subcontinent (approximate same latitude) 24 states east of Louisiana 25 states westernmost of Louisiana 31st rank order in physical size Total area (land & water): 49,651 sq. miles Alaska: capable of holding 12 Louisianas Louisiana: capable of holding 48 Rhode Islands

Boundaries One between Mississippi and Louisiana near the 31st parallel north (31° N latitude) Another between Arkansas & Louisiana near the 33rd parallel north (33° N latitude) Louisiana & Texas separated by 94th meridian west (94° W latitude) Upper boundary shaped by Mississippi River Lower boundary formed by Pearl River Southern boundary marked by the Gulf of Mexico Click here to return to Main Menu.

Section 2: Louisiana’s Waterways ESSENTIAL QUESTION: What are Louisiana’s major rivers and lakes?

Section 2: Louisiana’s Waterways What words do I need to know? navigable bayou terrain brackish cutoff lakes raft lakes marsh lakes

Louisiana’s Waterways Rivers Lakes Bayous

Rivers Names and meanings designated for the Mississippi River: Algonquin Indians: Messipe (meaning the “great river”) Spanish: Rio del Espiritu Santo (the river of the Holy Spirit) The “Nile of America” Area Mississippi River covers (1,245,000 square miles) Red River (2nd largest river drainage area) Other rivers: the Ouachita, Little, Tensas, Black, Atchafalaya, Pearl, Calcasieu, & Sabine

Lakes Manmade Lakes: Toledo Bend, Lake D’Arbonne, Lake Claiborne, Sibley Lake, & Lake Chicot Natural Lakes: Lake Pontchartrain (Louisiana’s largest – 625 square miles) & Lake Maurepas (lagoonal lake) Cutoff Lakes: False River, Lake Bruin, & Larto Lake Raft Lakes: Caddo Lake & Lake Bistineau Marsh Lakes: White Lake, Grand Lake, & Calcasieu Lake

Bayous Name most connected with Louisiana waterways Popular slogan “Louisiana, The Bayou State” Name derived from the Choctaw Indian language, meaning “creek” Designated as “the sleeping water” by early French culture Well-known bayous: Bayou Lafourche and Bayou Teche Click here to return to Main Menu.

Section 3: Louisiana’s Natural Regions ESSENTIAL QUESTION: What are the five major natural regions of Louisiana?

Section 3: Louisiana’s Natural Regions What words do I need to know? elevation 8. salt dome relief 9. geologist alluvial 10. delta swamp 11. floodplain estuary 12. loess topography 13. uplift marsh 14. wolds

Louisiana’s Five Major Natural Regions Mississippi Floodplain Region Terraces Region Marsh Region Red River Valley Region Hills Region

Mississippi Floodplain Region Floodplain – the level along a river that is likely to flood Mississippi floodplain region – a parallel to Mississippi River in the eastern part of the state Soil – deposited by the river (alluvial) Fertile soil – producer of abundant natural vegetation & valuable agricultural crops Floodplain region – divided into three parts: The Natural Levee, the Swamp, & the Passes

The Natural Levee Natural riverbanks – built up over time by silt deposits from flooding Natural Levees – Lie within 100 feet of the river & cover area of about 5 miles wide Rise 10 to 15 feet high: do not keep river from flooding Possessed a canebrake of switch cane in early times Batture – contains trees that survive flooding

The Swamp Lowest part of the river basin One definition: “a seasonally flooded forest” Much of New Orleans was built in the drained swamp of the Mississippi floodplain Cypress & tupelo gum trees abundant in swamp Spanish moss not harmful to trees - moss nutrients absorbed from the air

The Passes Routes the Mississippi River takes to merge with the Gulf of Mexico Area called a delta (mouth of river triangle-shaped like the Greek letter delta) Sometimes called the “birdsfoot delta” (looks like the foot of a monster-sized bird from the air)

Terraces Region Contains the old Mississippi floodplains Changed its course after every ice age Once natural levees & low swamps Three divisions in the Terraces Region The Blufflands The Prairies The Flatwoods

The Blufflands The old natural levees Highest part of the Terraces region Loess (wind-deposited soil) – causing increased heights of old levees Fine silt eroding easily – Result: vertical slopes on the high bluffs (good example: West Feliciana Parish) State Flower – the magnolia showcased by beautiful forests (blooms in summer) Other trees abundant: dogwood, holly, ash, & oak Ferns, green mosses, & wildflowers on forest floor

The Prairies Formed by old river channels Flat as a giant table top (hard clay just below topsoil – few trees) Similar to Midwestern United States 2,000,000 acres once grasses & wildflower: some common plants – broom & bluestem sedge, water & switch grass Resemblance of tall grass to rippling water – hence, occurrence of names like “points,” “islands,” & “coves”

The Flatwoods Covered with a forest Better soil drainage than Prairies, allowing trees to grow Covered with pine & hardwoods along with wire grass & palmetto Region called “piney woods” by early settlers

Marsh Region Located along Louisiana’s Gulf Coast More than 2.5 million acres of marsh People habitation along the chenier ridges French meaning of Chenier – “places of the oak” Sandy soil of chenier ridges (composed of shells and sand) Marsh grass in the fertile muck & peat soil Abundant rainfall & a long growing season Plant life & habitat for 180+ bird species

Salt Domes Found in the salt marsh Layers of rock that have folded upward Hold sulphur, petroleum, & salt Main domes between New Iberia & Morgan City called the Five Islands: Avery, Weeks, Jefferson, Cote, and Bell Islands Foods & petroleum products produced

Red River Valley Region Borders the Red River from the northwestern corner to central Louisiana Resembles small version of Mississippi Floodplain Single stream with natural levees & low-lying areas (fertile red soil found) Forests created by trees that survived flooding Contains some swamp forest

Hills Region Covers much of North Louisiana Highest region with roughest terrain Major part – Sabine Uplift (also called Dolet Hills) Included in Hills Region: Nacogdoches Wold & Kisatchie Wold (contains Louisiana’s highest point) Contains old (not fertile) soil – usually red due to iron content Much of region planted in tree farms Pine forest (part of vegetation in Hills) Click here to return to Main Menu.

Section 4: Louisiana’s Climate ESSENTIAL QUESTION: What is the difference between weather and climate and its effect on the people and the physical environment?

Section 4: Louisiana’s Climate What words do I need to know? weather climate precipitation hurricane (& hurricane eye) tornado growing season humid subtropical

Section 4: Louisiana’s Climate Weather & Climate Weather measures the current conditions of the atmosphere: temperature, precipitation, & wind Climate Climate is the average weather of an area over a long period of time, i.e., 25-30 years

Section 4: Louisiana’s Climate Affected by the Gulf of Mexico, distance, and position on North American continent Two climate regions: North Louisiana and South Louisiana Louisiana noted as humid subtropical Result of high pressure systems from Florida (carry large moisture amounts) Influenced by continental air masses

Section 4: Louisiana’s Climate Temperature Precipitation Wind Climate and Agriculture

Temperature North Louisiana – highest temperatures in the state South Louisiana – benefits from the cooling effects of the Gulf of Mexico Record state temperatures Highest: 114° August 10, 1936 Lowest: -16° February 15, 1899 Northwest Louisiana – greatest temperature range

Precipitation Water – liquid or solid – that falls from the atmosphere & reaches the ground Rain – most frequent precipitation Occasional summer hail storms Winter – sleet more common than rare snowfall Most rainfall – southeast Least rainfall – northwest Some areas annual rainfall, 48 inches 1899 – rare snowfall for all of Louisiana

Wind Causes worst weather Two kinds of windstorms Hurricanes Tornadoes

Tornadoes Give little warning Can develop in 5–10 minutes In clouds of a thunderstorm When cool air meets a layer of warm air Spotted by radar & computer technology Usually 50 mph, perhaps 100 yards wide Winds circling (up to 300 mph) inside funnel cloud Most damage caused by extreme low pressure (called the eye)

Hurricanes Begin over tropical ocean waters 74 mph minimal wind speed Rotation of hurricane winds around calm center or eye Energy created from warm, moist air Attacks coastline with high winds & high water (10-20 feet, possible) Can cause major flooding Greatest risk in September, although season from June 1 to November 30

Hurricanes More than 60 hurricanes have hit Louisiana in past 150 years Recent hurricanes include: Audrey (1957), Betsy (1965), Andrew (1992), Katrina (2005) 2005: Hurricanes Katrina & Rita – flooded New Orleans. More than 1000 died; damage over $25 billion

Climate and Agriculture Effect of climate & weather on natural environment important Growing season 210 days in north-central Louisiana 290 days near the Passes Occurrence of severe freeze – once every 7 years at mouth of Mississippi Important crops: citrus trees, strawberries, sugar cane & cotton Click here to return to Main Menu.

Section 5: People and the Environment ESSENTIAL QUESTION: What are the factors that have affected Louisiana’s coastline and the ways in which people have affected the environment?

Section 5: People and the Environment What words do I need to know? wetlands subsidence barrier island time zones nutria Asian carp

Descriptions of the Mississippi River Conflicting relationships indicated between people & the river Names assigned to Mississippi: “father of waters” “great artery of the continent” “unruly neighbor of the farmers” “raging killer of small towns”

Flood Control 1719 – Flood warnings ignored by French king, first levees soon built 1927 – Great flood driving ½ million people from homes, leading to new system: U.S. Army Corps of Engineers responsible for controlling flooding Bonnet Carre Spillway built 1935 Old River Structure completed 1963 Plan to protect people & property disastrous for Louisiana’s wetlands

Vanishing Coastline Louisiana in a crisis State having 30% of U.S. coastline; experiencing 90% land loss Since 1950 land loss comparable to area size of Delaware Once dry lands now covered by water

Causes Sustenance of marsh dependent on rivers, water runoff, & silt Causes of coastline’s sinking: Flood-control efforts reducing the amount of silt Underground faults resulting in shifting and sinking of land

Impact of the Land Loss Louisiana ports vital to U.S. economy Handles 20% of all U.S. imports Supplies more than ⅓ of U.S. oil & gas needs Coastal marshes Provides 75% of Gulf of Mexico’s seafood industry Generates annual billion $ income Impacts habitat of migratory birds & waterfowl Barrier islands affected by coastal changes Lessens effectiveness of islands & marshes to protect from hurricane storm surge Brings about possible losses: Buildings, railroads, highways Humans, wildlife, & natural environment Coastal erosion

Response Early damage to the marsh unnoticed Billions needed to correct problems 1990 Senator John Breaux responsible for U.S. Congressional bill to save wetlands: CWPPRA (the Coastal Wetlands Planning, Protection & Restoration Act) Federal funds for wetlands projects Hopeful to create a new manmade river channel to re-direct Mississippi River Scientists studying flood control options in light of hurricane Katrina

Other Environmental Problems Efforts to save Louisiana’s coast: Environmental groups The Nature Conservancy Unintended negative impacts: water hyacinth nutria Asian carp Click here to return to Main Menu.

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