Let’s learn about nature's filter system and why it is important to southeast Texas. During this Earthcache you will visit three locations, learn a little about our region and then reflect on why this area is important.
The Coastal Prairie
The Coastal Prairie is located along the western Gulf Coast of the United States, in southwest Louisiana and southeast Texas, just inland from the coastal marsh. The Coastal Prairie is one of 21 different soils found in Texas. The Coastal Prairie was estimated that, in pre-settlement times, there were nine million acres of Coastal Prairie, with 2.5 million acres in Louisiana and 6.5 million acres in Texas.
As you turn to the west from GZ and walk around the park, you will notice developments here in western Harris County. This development within the Coastal Prairie means that less than one percent of the prairie remains. The top three reasons for the prairie loss are construction, cattle raising, and farming.
Freshwater Wetlands
Simply stated, wetlands are parts of our landscape that are defined by the presence of water. Wetlands provide flood protection, improve water quality and provide millions of dollars in economic benefits each year. There are three benefits of Wetlands are improving water quality, supporting the natural environment and providing habitat.
Improving water quality is one of the most important aspects that a wetland can do. Wetlands absorb and filter sediments, nutrients, and other natural and man-made pollutants that would otherwise damage rivers, lakes, and streams.
Types of Wetlands
There are many different types of wetlands, each determined by its hydrology, water chemistry, soils, and the plant species found there. Wetlands may be characterized as dominated by trees, shrubs, or herbaceous vegetation. They may be fed by precipitation, runoff, or groundwater, with water chemistry ranging from very acidic to alkaline.
There are four types of Wetlands: Pond, Marsh, Swamp, and Peat Bog.
A Pond is a well-defined basin that is filled with stagnant water and ringed by vegetation. It is fed mainly by rainstorms and snowmelt and loses most of its water through seepage and evaporation. In hot, dry months, parts of a Pond may dry out, exposing mudflats. In shallow Ponds, bottom rooted plants can reach the surface.
A Marsh is usually found near a river, lake or tidal waters. Marshes are subject to periodic flooding, and the water level can change drastically in a short amount of time. The boundaries of a marsh are not well defined, and in a drought, a marsh can completely dry up. Marshes are overgrown with coarse grasses, sedges, and rushes.
A Swamp is essentially a wooded marsh. Unlike Marshes, Swamps can support trees, tall shrubs, herbs, and mosses. Swamps are covered with still or gently flowing water during wet seasons.
A Peat bog is a poorly drained area that is covered by mats of moss, which slowly decompose in successive layers and eventually form a material called peat. There are 2 types of peat bogs; Bogs and Fens. The water of a Bog is much more acidic than that of a Fen, due to the larger quantities of sphagnum moss and the more advanced process of decomposition in a Bog.
Natures Filter
Wetlands trap oil, nitrogen, phosphorus, sewage and other pollutants. Because wetlands naturally help break down and absorb pollutants in the water, wetlands save cities and towns up to $1.6 billion a year in cleanup costs to water supplies. In addition, the wetlands, like the one before you can reduce flood damage. During a flood, the force of the water flowing through an area often causes more damage than rain and wind combined. Wetlands plants help stem the flow, reducing erosion and, over time, slowly releasing floodwater into rivers, streams, underground aquifers, and the atmosphere. Protecting wetlands saves up to $30 billion a year in flood-related repair costs in the United States alone.
The primary way that wetlands filter water is through their role in water flow. As sediment-containing water passes through wetlands, the water flow slows. Sediment will drop out of the water and become part of the ground layer. In this way, the water becomes clearer and sediment is removed which otherwise creates cloudy water conditions.
To log this Earthcache:
- Go to N 29 48.544 W 095 47.573
a. Describe the speed and color of the water entering the wetlands.
2. Go to N 29 48.559 W 095 47.154
- Describe the water level here. Is the water high or low? Look to the west and you will see a white water gauge.
- What color is the water passing underneath you? How is it different than wave point one?
- Describe what you think has happened to the water.
- Look to the west, what do you think are three ways that pollutants enter the wetland?
3. Go to N 29 48.774 W 095 47.339
a. Describe the water level here. What has happened to the ground to the south of you, describe what has happened?
b. Reflect on your walk around the wetland. What type of wetland have you been observing?
Optional: Post a picture of yourself at your favorite spot along the trail.
Harris County Precinct 3 Commissioner Mike McMahan approved this Earthcache
Follow all posted rules and regulations of Harris County Parks
References:
U.S. Fish and Wildlife Service. 1999. Paradise Lost? The Coastal Prairie of Louisiana and Texas. https://www.nwrc.usgs.gov/prairie/paradise_lost.pdf
The United States Environmental Protection Agency. 2018. Classification and Types of Wetlands. https://www.epa.gov/wetlands/classification-and-types-wetlands#marshes
Texas Parks and Wildlife. 2018. Texas Treasures: Wetlands. https://tpwd.texas.gov/publications/pwdpubs/media/pwd_bk_k0700_0908.pdf