The Rio Grande forms this region's southern border and New Mexico borders it to the north. There is also Big Bend National Park in this region.
The Basin and Range province, with its center in Nevada, surrounds the Colorado Plateau on the west and south and enters far West Texas from southern New Mexico on the east. It consists of broad interior drainage basins interspersed with scattered fault-block mountain ranges. Although this is the only part of Texas regarded as mountainous, these should not be confused with the Rocky Mountains. Broad basins and valleys bordered by sloping alluvial fans and terraces make up the dry lowlands of this region, punctuated by occasional mesas and mountain ranges.
In this arid region, riparian corridors provide important habitat for breeding, in-transit, and wintering birds. Other drainages end in closed basins and include few permanent streams. Arid grass and shrubland are the primary lowland vegetation types, often dominated by creosote. This grades uphill into oak-juniper woodlands and even coniferous forest in the highest reaches. The Madrean mountains mark its western edge, the Edwards Plateau its east, and the reduced shrubbiness of the shortgrass plains its north.
The inland boundary of this area ranges from 15 km to km from the coast, capturing a complex of marshes and upland grassland and a very small amount of forested habitat. Marsh vegetation is determined largely by the salt content of the water, with community types ranging from salt marsh to brackish to fresh water marsh. Nearly all grassland habitats have been converted to agricultural use, primarily pasture lands and rice farms.
Forested areas occur primarily along major riverine systems and on coastal cheniers ancient beachfront ridges , mottes and salt domes, and man-made levees and spoil banks. These are long narrow bands of woodlands dominated by hackberry and live oak that run parallel to the Gulf Coast and range in width from about 30 to m and in length from about 1 to 50 km. Bottomland hardwood forests along the major river systems that drain the Coastal Prairies range in composition from cypress-tupelo to hackberry-ash-elm to water oak-willow oak dominated forest.
The Edwards Plateau is entirely contained within Texas. This hilly area is clearly demarcated by the Balcones Fault escarpment to the east and south, but grades into the Chihuahuan Desert to the west and the Great Plains to the north. The plateau can be divided into four subregions. The central and western portions of the plateau are characterized by broad, relatively level uplands moderately dissected by gently sloping stream divides.
The deeply dissected portion adjacent to the escarpment, the Balcones Canyonlands, is popularly known as the Texas Hill Country. This region is highly dissected by fast-moving streams through steep-sided canyons. The northeast plateau, the Lampasas Cut Plains, is characterized by broad valleys. This area has a granitic substrate that clearly differentiates this area from surrounding areas. The Edwards Plateau was originally a grassy savannah with the most common trees being mesquite, juniper, and live oaks.
In the increasingly arid west, however, its forests become secondary in nature, consisting largely of post oaks and, farther west, prairies and brushlands. This geologic fault or shearing of underground strata extends eastward from a point on the Rio Grande near Del Rio. It extends to the northwestern part of Bexar County, where it turns northeastward and extends through Comal, Hays, and Travis counties, intersecting the Colorado River immediately north of Austin.
The fault line is a single, definite geologic feature, accompanied by a line of southward- and eastward-facing hills. The resemblance of the hills to balconies when viewed from the plain below accounts for the Spanish name for this area: balcones. North of Waco, features of the fault zone are sufficiently inconspicuous that the interior boundary of the Coastal Plain follows the traditional geologic contact between upper and lower Cretaceous rocks. This contact is along the eastern edge of the Eastern Cross Timbers.
This fault line is usually accepted as the boundary between lowland and upland Texas. Below the fault line, the surface is characteristically coastal plains. Above the Balcones Fault, the surface is characteristically interior rolling plains. From north to south, it extends from the Red River to within about 25 miles of the Gulf Coast.
Interspersed among the pines are hardwood timbers, usually in valleys of rivers and creeks. Cattle raising is widespread, along with the development of pastures planted to improved grasses.
Lumber production is the principal industry. There is a large iron-and-steel industry near Daingerfield in Morris County based on nearby iron deposits. Iron deposits are also worked in Rusk and one or two other counties. A great oil field discovered in Gregg, Rusk, and Smith counties in has done more than anything else to contribute to the economic growth of the area.
This area has a variety of clays, lignite, and other minerals as potentials for development. The principal industry is diversified farming and livestock raising. Throughout, it is spotty in character, with some insular areas of blackland soil and some that closely resemble those of the Pine Belt.
The Post Oak Belt has lignite, commercial clays, and some other minerals. The Blackland Belt stretches from the Rio Grande to the Red River, lying just below the line of the Balcones Fault and varying in width from 15 to 70 miles. It is narrowest below the segment of the Balcones Fault from the Rio Grande to Bexar County and gradually widens as it runs northeast to the Red River.
Its rolling prairie, easily turned by the plow, developed rapidly as a farming area until the s and was the principal cotton-producing area of Texas. Now, however, other Texas areas that are irrigated and mechanized lead in farming. Primarily because of this concentration of population, this belt has the most diversified manufacturing industry of the state.
The Texas Coastal Prairies extend westward along the coast from the Sabine River, reaching inland 30 to 60 miles. Between the Sabine and Galveston Bay, the line of demarcation between the prairies and the Pine Belt forests to the north is very distinct.
The eastern half is covered with a heavy growth of grass; the western half, which is more arid, is covered with short grass and, in some places, with small timber and brush.
The soil is heavy clay. Grass supports the densest cattle population in Texas, and cattle ranching is the principal agricultural industry. Ecosystem Diversity in Louisiana. Landforms Near Chicago. The Climate of the Edwards Plateau. Sierra Nevada Mountain Facts for Kids. About the Climate of Texas. Mountains of West Africa.
Landforms of Connecticut. Major Landforms in the Southwest Region. The western portion of the coast is primarily grasslands and prairies. The average rainfall is from 40 to 60 inches a year. The Texas Hill Country is located in the central portion of Texas.
Most of the land is a hilly grassland. It was formerly a plateau, which has evolved into a hilly terrain after millions of years. The land used to be full of multiple springs, but due to human interference, this amount has dwindled down. The San Marcos Springs are the most well known natural landform in the region. The total size of the Edwards Plateau in this region is 31, square miles. The average rainfall here is 15 to 34 inches a year. The panhandle plains are located in the northern region of Texas, named primarily due to the resemblance to the appearance of an upside-down pan.
Most of the area is flat and grassy with little to no trees. The eastern portion of the plains receives more rain than the western part.
The area of the Pandhandle Plains is 81, square miles overall. Piney Woods is in the eastern portion of the state.
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