Watershed Report
Arturo Delgado Jr. April 23, 2013 ESSM 301-‐507
RAINFALL, INFILTRATION, AND INFLUENCING FACTORS
Introduction In this study, a rainfall simulation was conducted in order to measure infiltration rates at the Low Stony Hill site in Gatesville, Texas. Rainfall simulations are important contributors to understanding infiltration and factors, which influence infiltration rate, such as bulk density, plant biomass and percent cover, and topography. The objective of this study is to utilize the rainfall simulation to examine and understand the interrelationships of the factors that influencing infiltration and how these factors directly influence infiltration. Site Description The study area is in Gatesville, Texas in Coryell County called the Low Stony Hill range site, which is located at 31° 23’ N and 97° 43’ W at an elevation of 231.6 m (NOAA 2005). The study area is primarily composed of live oak savannah with a tree canopy cover of less than 20 percent. Live oak mottes, elm (Ulmus spp.), and hackberry (Celtis occidentalis) can be found along water basins (GREER 2005). The vegetation in the Low Stony Hill site is composed of 85% herbaceous vegetation, 10% woody vegetation, and 5% forbs (Greer 2005). A few of the notable herbaceous species include little bluestem (Schizachyrium scoparium), sideoats grama (Bouteloua curtipendula), and big bluestem (Andropogon gerardi). The vegetation of Low Stony Hill is also composed a variety of species of forbs. The soils at this site include Eckrant cobbly silty clay (EcB) soils ranging from shallow to very shallow; however, the soil is well drained with moderately slow permeability and rapid surface runoff with 1-3 percent slopes. Methods Soil characteristics, which affect infiltration rates and are crucial to understanding infiltration, include bulk density, vegetation, and microtopography. To assess and calculate these characteristics, 32 microplots (0.35 m2) were used – 16 dominated by
RAINFALL, INFILTRATION, AND INFLUENCING FACTORS
Introduction In this study, a rainfall simulation was conducted in order to measure infiltration rates at the Low Stony Hill site in Gatesville, Texas. Rainfall simulations are important contributors to understanding infiltration and factors, which influence infiltration rate, such as bulk density, plant biomass and percent cover, and topography. The objective of this study is to utilize the rainfall simulation to examine and understand the interrelationships of the factors that influencing infiltration and how these factors directly influence infiltration. Site Description The study area is in Gatesville, Texas in Coryell County called the Low Stony Hill range site, which is located at 31° 23’ N and 97° 43’ W at an elevation of 231.6 m (NOAA 2005). The study area is primarily composed of live oak savannah with a tree canopy cover of less than 20 percent. Live oak mottes, elm (Ulmus spp.), and hackberry (Celtis occidentalis) can be found along water basins (GREER 2005). The vegetation in the Low Stony Hill site is composed of 85% herbaceous vegetation, 10% woody vegetation, and 5% forbs (Greer 2005). A few of the notable herbaceous species include little bluestem (Schizachyrium scoparium), sideoats grama (Bouteloua curtipendula), and big bluestem (Andropogon gerardi). The vegetation of Low Stony Hill is also composed a variety of species of forbs. The soils at this site include Eckrant cobbly silty clay (EcB) soils ranging from shallow to very shallow; however, the soil is well drained with moderately slow permeability and rapid surface runoff with 1-3 percent slopes. Methods Soil characteristics, which affect infiltration rates and are crucial to understanding infiltration, include bulk density, vegetation, and microtopography. To assess and calculate these characteristics, 32 microplots (0.35 m2) were used – 16 dominated by