TEXAS
ECOREGIONS
Effects of Weathering,
Erosion and Deposition
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
IN THE NATURAL WORLD, ENVIRONMENTS ARE
CHARACTERIZED BY:
Types
of soil
Precipitation
Temperature
Land features
Vegetation
Animal wildlife
FACTORS AFFECTING OUR ECOREGIONS:
1.
Weathering – chemical and physical break
down of rocks into sediment
2.
Erosion – the movement of sediment from one
place to another
3.
Deposition – the placement of sediment after
being carried from place of origin
1. PINEY WOODS
Due to abundant
precipitation and
abundant vegetation
that holds the soil in
place, there is very little
erosion.
 Thick vegetation near
rivers inhibits river
erosion.
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2. OAK WOOD & PRAIRIES
Has gently rolling hills
and lightly wooded
plains.
 This area generally
receives a moderate
amount of rainfall that
helps shape the land.
 Trees and grasses
prevent large amounts
of soil erosion due to
water and wind.
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3. BLACKLAND PRAIRIE
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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.
If the land is used for
farming and it is not
managed well, nutrients
will be quickly used up.
4. GULF COAST PRAIRIES
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Wave action, a cause of
weathering, erosion and
deposition, is constant
along the Texas Coastline.
Sediments are weathered
and eroded along beaches
and carried out into the
ocean to form sand bars
and islands.
When rivers, like the
Brazos enter the Gulf of
Mexico sediment being
carried by the river stop
moving and get deposited
causing a delta.
5. COASTAL SAND PLAIN
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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.
Catastrophic events
such as hurricanes can
increase wave erosion
and deposition.
6. SOUTH TEXAS BRUSH COUNTRY
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The area is known as
“Brush Country” due to
the shorter trees and
many shrubs.
Overgrazing of the land
has allowed nutrientrich topsoil to erode
way.
Rocky, dry soil cannot
support grasses, trees
can thrive because of
their deeper root
system.
7. EDWARDS PLATEAU
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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.
Rainwater mixes with
carbon dioxide in the
atmosphere and soils to
form carbonic acid, which
acts to dissolve away
limestone.
8. LLANO UPLIFT
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The soil is not as prone to
flooding because it allows water
to infiltrate very easily.
The region is described as rough,
hilly terrain.
Enchanted Rock-Exfoliation has
caused the rock to “peel” in sheets.
This was caused by contracting and
expanding during heating and
cooling in the temperature.
The weathering of sedimentary rock
has exposed the granite dome
underneath
Other types of mechanical
weathering present – plant roots
9. ROLLING PLAINS

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.
10. HIGH PLAINS
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“Texas Panhandle”-Largest
and most completely flat
areas of it size in the world!
The region extends to the
Palo Duro Canyon-the
nation’s 2nd largest canyon.
Palo Duro Canyon was
formed by water erosion
from the Prairie Dog Town
Fork of the Red River.
The water deepens the
canyon by moving sediment
downstream. Wind and water
erosion gradually widen the
canyon
11. TRANS PECOS
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Rain does not fall evenly over the
area. “Desert portion” of Texas.
The weathered bedrock in this area
have a large amount of calcium.
Erosion and deposition in the area
creates soil which has high
amounts of calcium called caliche.
Home of the tallest mountain in
Texas, Guadalupe Peak. Elevation
is 8,749 feet.
Pines and Oaks dominate the tree
species.
Soils are shallow and rocky.
Weathering continues to play a
role in developing soil and will for
thousands of years to come. Soils
in the canyon bottoms and valleys
are deeper as a result of
deposition.
12. MARINE ENVIRONMENT
Marine topography refers to the shape the land
along coastlines, but they occur also in significant
ways underwater.
 The effectiveness of marine habitats is partially
defined by these shapes, including the way they
interact with and shape ocean currents.
 Marine topographies include coastal and oceanic
landforms ranging from coastal estuaries and
shorelines to continental shelves and coral reefs.
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Our Next Step:
Analyzed the characteristics of the
ecoregions of Texas
Investigated processes that change
the surface of the Earth
Explored how the process of
weathering, erosion, and deposition
have affected the environments in
Texas ecoregion.