What Is An Ecoregion?What Is An Ecoregion?

• Ecoregion - a major ecosystem with distinctive geography, characteristic plants and animals, ecosystems, and receiving uniform solar radiation and moisture – Sometimes called an ecological region or

bioregion– Smaller than a biome

Focus

Which feature on the list can be found and observed in Texas?

a. Deserts b. Canyons c. Mountains d. Beaches e. Meadows of wildflowers f. Swamps g. Pine forests

Yes, we have them all in Texas!

• a. Deserts — Chihuahuan Desert • b. Canyons— Palo Duro Canyon • c. Mountains— Guadalupe Mountains • d. Beaches— Galveston Beach • e. Meadows of wildflowers—

Hill Country/Central Texas • f. Swamps—Daisetta Swamp, Liberty County • g. Pine forests— Big Thicket National Preserve

Palo Duro Canyon

Galveston Beach

Guadalupe Mountains

Chihuahuan Desert

Hill Country

Daisetta Swamp

Big Thicket National Preserve

Region 1Region 1Piney Woods

• Climate: average annual rainfall of 36 to 50 inches is fairly uniformly distributed throughout the year, and humidity and temperatures are typically high

• Soil: generally acidic and mostly pale to dark gray sands or sandy loams

• Elevation: ranges from 200 to 500 feet above sea level• Geography: rolling terrain• Vegetation: pine and oak tall hardwood forests with

scattered areas of cropland, planted pastures, native pastures, and rich bottomlands

Plants, animals

Weathering, erosion, deposition

• The Piney Woods is the wettest region of the state. This allows for a high rate of plant decay to occur resulting in healthy, nutrient-rich soils.

• The topography is gently rolling to near flat throughout the region. Soils are somewhat poorly drained and streams are slow-moving.

The majority of economic activities involve the lumber industry and unless an area has been clear-cut of vegetation, the amount of trees and plants can prevent erosion.

Region 2Oak Woods & Prairies

•Climate: Average annual rainfall averages 28 to 40 inches per year•Soil: Upland soils are light colored, acidic sandy loam or sands. Bottomland soils may be light brown to dark gray and acidic with textures ranging from sandy loams to clays•Elevation: ranges from 300 to 800 feet above sea level•Geography: gently rolling to hilly terrain•Vegetation: oak savannah, where patches of oak woodland alternate with grassland

Region 3

Blackland Prairies•Climate: average annual rainfall ranges from 28 to 40 inches. May is the peak rainfall month for the northern end of the region; however, the south-central part has a fairly uniform rainfall throughout the year. •Soil: soils are uniformly dark-colored alkaline clays interspersed with some gray acidic sandy loams.•Elevation: ranges from 300 to 800 feet above sea level•Geography: gently rolling to nearly level terrain•Vegetation: food and forage crops

Region 4Gulf Coast Prairies and Marshes

•Climate: annual rainfall varies from 30 to 50 inches per year, high humidity and warm temperatures •Soil: acidic sands and sandy loams, with clays occurring in the river bottoms•Elevation: nearly level, less than 150 feet above sea level, cut by streams and rivers flowing into the Gulf of Mexico•Geography: barrier islands along the coast, marshes near bays and estuaries, and prairies•Vegetation: salt grass, tallgrass prairies, live oak woodlands, mesquite and acacias, oaks scattered along the coast, and tall woodlands in the river bottomlands

Region 5Coastal Sand Plains

•Climate: Average annual rainfall is 24 to 28 inches per year •Soil: primarily sands•Elevation: fairly level with elevations less than 150 feet above sea level•Geography: windblown sands and unstable dunes with grasslands, stands of oak, and salt marshes•Vegetation: tallgrass prairie with live oak woodlands, mesquite savannah, and salt marshes

Location

Aransas PassBeaumontCorpus ChristiGalvestonHoustonRefugioRockportSouth Padre IslandVictoria

Plants, animals

Weathering, erosion, deposition• Soil in the region is primarily sand-based.• If there isn’t enough vegetation to keep

the soil in place, rainfall received can cause severe erosion.

• Small wave deltas form between the barrier islands

Sand dunes are a result of wind deposition

• Catastrophic events such as tropical storms can increase wave erosion and deposition.

Region 6South Texas Brush Country

•Climate: average annual rainfall of 16 to 35 inches increases from west to east. Summer temperatures are high, with very high evaporation rates•Soil: alkaline to slightly acidic clays and clay loams and shallow caliche soils •Elevation: ranges from sea level to 1000 feet•Geography: flat plains to gently rolling terrain •Vegetation: thorny shrubs, trees, and cactus scattered with patches of palms and subtropical woodlands

Region 7

Edwards Plateau•Climate: average annual rainfall ranges from 15 to 34 inches•Soil: usually shallow with a variety of surface textures, underlain by limestone•Elevation: ranges from slightly less than 100 feet to over 3,000 feet above sea level•Geography: many springs, stony hills, and steep canyons and caves; several river systems dissect the surface, creating a rough and well-drained landscape•Vegetation: grasslands, juniper/oak woodlands, and plateau live oak or mesquite savannah

Region 8 Llano Uplift

•Climate: averages about 24 to 32 inches per year•Soil: coarse textured sands, produced from weathered granite over thousands of years•Elevation: ranges from 825 to 2,250 feet above sea level•Geography: some of the oldest rocks in Texas, the region contains unique minerals and rock formations and large granite domes; hilly to rolling landscape•Vegetation: oak-hickory or oak-juniper woodlands, mesquite-mixed brush savannah, and grasslands

Location

AustinSan Antonio

Plants, animals

• The shape of the hills in this region is rounded due to increased precipitation

and chemical weathering.

Weathering, erosion, deposition

•Erosion by streams and rivers above ground has left most of the region with very shallow soils (less than 10 inches).

• Central Texas' Flash Flood Alley is one of the most flood-prone areas nationwide. When rocks and soil can absorb no more rainfall, it gets carried off into a stream or at the bottom of a lake

Erosion below ground caused by water seeping through the porous limestone. It contribute to the recharge of the Edwards Aquifer

The Llano Basin gets its name from the granitic rock that is uncovered at the surface. There are several large thin sheets of rock that slough off. This is a form of mass movement (erosion)called exfoliation.

Region 9Rolling Plains

•Climate: average annual rainfall is 20 to 28 inches; dry summers with high temperatures and high evaporation rates•Soil: vary from coarse sands along outwash terraces by streams, to clays and shales•Elevation: ranges from 800 to 3,000 feet above sea level•Geography: gently rolling hills and broad flats are cut by several rivers and their tributaries •Vegetation: mesquite and shortgrass savannah; various hardwood species along streams, juniper on steep slopes along rivers

Region 10High Plains

•Climate: extended droughts have occurred several times this century•Soil: surface texture of soils ranges from clays in the north to sands in the south; Caliche underlies these surface soils at depths of two to five feet•Elevation: ranges from 3,000 to 4,500 feet above sea level•Geography: relatively level high plateau•Vegetation: mostly irrigated cropland; native vegetation includes mesquite and juniper

Location

AmarilloLubbock

Palo Duro Canyon

Plants, animals

Weathering, erosion, deposition

• Largest and most completely flat areas of it size in the world. It is subjected to high wind speeds.

• Higher elevation because the rocks don’t wear down easily.

Weathering, erosion, deposition

• Catastrophic events such as tornados can increase wind erosion

•Poor land management, drought, and high wind speeds contributed to the Dust Bowl in the 1930’s

Region 11Trans Pecos

Climate: 9-15 inches of rain; semi-arid, warm, dry winters

Soil: generally shallow, saline, and unproductive

Elevation: 2,000 feet to mountain ranges, highest peak is 8,751 feet above sea level

Geography: salt basins, sand hills, rugged plateaus, mountain slopes

Vegetation: desert grassland, desert scrub, coniferous and mixed hardwood forests at mountain peaks

Location

El PasoPresidio

Big Bend National Park

Plants, animals

Weathering, erosion, deposition

• The weathered bedrock in this area has high amounts of calcium

• As a result of erosion and deposition in the area, the soil has high amounts of calcium called caliche.

Weathering, erosion, deposition

• It is the hottest and most arid (driest) region of the state.

• Hot days, cool nights contribute to physical weathering of rock.

Alluvial fans of rubble, sand, and gravel build at the base of the mountains

Weathering, Erosion, Deposition

• This region also has salt flats, dunes and windblown sand.