Texas Ecoregions

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Texas Ecoregions

• Effects of Weathering, Erosion and Deposition

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What is an Ecoregion?

• an area defined by its environmental conditions,
  esp. climate, landforms, and soil characteristics.

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Factors Affecting Our Ecoregions

• Weathering chemical and physical break down of
  rocks into sediment
• Erosion the movement of sediment from one place
  to another
• Deposition the placement of sediment after
  being carried from place of origin

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Piney Woods

• It is the wettest region of the state.
• This allows for a high rate of decomposition to
• occur resulting in healthy, nutrient-rich
  soils.
• The topography is gently rolling to near flat
  through out the region.
• Pine trees, woody vines, and hardwood trees
  dominate the vegetation.
• Unless an area has been clear-cut of vegetation
  for construction, the amount of trees and plants
  can prevent erosion.
• Very little erosion takes place in these areas.

http//www.youtube.com/watch?v9o8lKGhJ5KIlistPL
6353227E5419A80D
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Oak Wood Prairies

• These areas have nutrient-rich soils and receive
  good amounts of rainfall through the year.
• If the land is clear-cut of natural vegetation
  for construction nutrients can easily be eroded
  by wind and water.

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Blackland Prairies

• Large herds of bison grazed on the grasses at one
  time.
• Blackland prairies in Texas, which are mostly
  composed of clays, are eroded primarily by water.
  Secondary causes include wind, and the action of
  burrowing animals (bio erosion).

http//www.youtube.com/watch?vlBl-FruPos0listPL
6353227E5419A80D
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Gulf Coast Prairies and Marshes

• A narrow band about 60 miles wide along the Texas
  coast from the Louisiana border to Brownsville
  roughly outlines the Gulf Coast Prairies and
  Marshes
• Near the gulf waters you can see marshes, barrier
  islands, estuaries (where salty sea water and
  fresh river water meet), and bays.
• Catastrophic events such as hurricanes can
  increase wave erosion.

http//www.youtube.com/watch?vmZdsyKaIAYElistPL
6353227E5419A80D
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Llano Uplift

• A basin in some places, it is 1000 feet below
  the level of the surrounding limestone
  escarpment.
• It gets its name from the granitic mass that is
  exposed in the basin, granite that has been dated
  at one billion years old.
• Upland soils are shallow, reddish brown, stony,
  sandy loams over granite, gneiss, and schist with
  deeper sandy loams in the valleys.

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South Texas Brush Country

• The area is known as Brush Country due to the
  shorter trees and many shrubs.
• Overgrazing of the land has allowed nutrient-rich
  topsoil to erode way by wind and water.
• Rocky, dry soil cannot support grasses, trees can
  thrive because of their deeper root system.

http//www.youtube.com/watch?vXyluCiAOdsolistPL
6353227E5419A80D
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Coastal Sand Plains

• Soil in the region is primarily sand-based.
• If there isnt enough vegetation to keep the soil
  in place, rainfall received can cause severe
  erosion.
• Catastrophic events such as hurricanes can
  increase wave erosion.

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Edwards Plateau

• This region is located between dry western plains
  and moist prairies and woods.
• Unfortunately, water erosion has left most of the
  region with very shallow soils (less than 10
  inches) lined with limestone rock layers.
• High amounts of rain in a short amount of time
  can. cause flash flooding

http//www.youtube.com/watch?vDY7ueukM1QQlistPL
6353227E5419A80D
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Rolling Plains

• This region is part of the Great Plains of the
  central United States.
• Soils in this area are most fertile and sought
  after for crop production.
• Periods of drought and then sudden increase in
  rainfall causes large amounts of erosion and
  deplete the soil of nutrients.

http//www.youtube.com/watch?v0UlDeYfJ1XUlistPL
6353227E5419A80D
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High Plains

• Texas Panhandle
• Largest and most completely flat areas of it size
  in the world!
• The High Plains ecoregion is one of the windiest
  regions in the United States.
• The climate is generally dry, and areas without
  vegetation experience wind erosion.
• The Palo Duro Canyon was formed by water erosion
  by a fork of the Red River. The canyon continues
  to become deeper as the water moves sediment
  downstream. Wind and water erosion gradually
  widen the canyon.

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Trans-Pecos

• Desert portion of Texas.
• The weathered bedrock in this area has high
  amounts of calcium.
• The Guadalupe Mountains and the Davis Mountains
  are located in this ecoregion, making it the most
  mountainous area of Texas.
• In general, soil in this region is eroded due
  to the decline of grasslands.
• Flash-flooding and rapid runoff are causes of
  erosion in the park.
• Erosion of the limestone cliffs takes place
  because of acid rain.
• http//www.youtube.com/watch?vb1FErNrxVZolistPL
  6353227E5419A80D

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Marine Environment

• This ecoregion has seagrasses, oyster reefs,
  barrier islands, muddy estaurine bottoms, reefs
  and open water.
• These areas provide plants and animals with their
  basic needs and support hundreds of species.
• Global warming has one of the most negative
  impacts in marine ecosystems.