Discipline: Ecology Environmental and Earth Sciences
Subcategory: Geosciences and Earth Sciences
Session: 2
Room: Park Tower 8206
Titilope Bukunmi-Omidiran - Texas Southern University
Co-Author(s): Maruthi Sridhar Balaji Bhaskar, Texas Southern University, Houston, TX
The Buffalo and Brays bayous run through the center of the Houston metropolis and these watersheds are home to about 1.5 million inhabitants of the 6.6 million population in the region. Both the Buffalo and Brays bayous run parallel to each other and are about 104.1km and 50.7km in length, respectively. A category 4, Hurricane Harvey has made landfall on South Texas resulting in heavy precipitation of about 33 inches rainfall from Aug 25 to 29 of 2017 in Houston. The rapid urbanization of Houston along with the intense rain events are resulting in significant changes in the soil and water quality of the surrounding watersheds, hence the goal of this research is to assess the differential impact of land use activities and high rainfall on the soil and water quality of the Buffalo and Brays bayou watersheds of Houston-Galveston Region. The specific objectives of the study are 1) To determine the nutrient and metal concentrations in the soil and water samples collected along the Buffalo and Brays bayou watersheds during the pre- and post-Harvey events and 2) To map and quantify the spatial distribution of the chemical concentrations along the bayous. A total of 21 water and 62 soil samples were collected from several locations along the Buffalo and Brays bayou during pre- and post-Harvey sampling. All the geographical coordinates of the sample locations were marked with a handheld GPS unit. The samples were immediately brought to the lab and prepared for chemical analysis. The water and soil samples were microwave digested with 600µl of HNO3 and 400µl of HCl and then further analyzed for elemental concentrations by using the Inductive Coupled Plasma Mass Spectrometer (ICP-MS). The soil and water samples were also analyzed for C and N concentrations using the total Carbon and Nitrogen (TCN) analyzer. The soil and water samples were analyzed for C, N, P, K, Ca, Mg, Al, Fe, Cd, As, Pb, Cu, and Cs amongst other elements. Spatial analysis of the data was conducted using the ESRI Arc GIS 10.3 software. The resultant data from the chemical analysis for soil showed higher concentrations of Cs in the post-Harvey samples collected in Fall 2017 across both Buffalo and Brays bayous. The As concentrations increased downstream and Cd concentrations increased at all sampling points in the soil samples of post-Harvey. In the water samples higher concentrations of Fe and Al were observed in the pre-Harvey samples compared to the post-Harvey samples. Our geospatial maps showed that the Pb concentration in the soil samples increased downstream along the Buffalo and Brays bayous in the post-Harvey samples, this can be attributed to the hurricane Harvey flood event which flushed water out many Pb coated pipes. This research is significant as it shows the impact of the natural and human activities on the Brays and Buffalo Bayous of Houston, Texas and the long-term consequences on the environmental health of the Houston metropolis which can be continuously monitored.
Funder Acknowledgement(s): This research was primarily supported by the National Science Foundation (NSF) through Texas Southern University (TSU) under the award numbers HRD-1400962 and HRD-1622993. I thank Naomi Walker, Akinsanya Adesope, Habibur Howlider in collecting the soil and water samples and Djene Keita for her help in processing the samples.
Faculty Advisor: Maruthi Sridhar Balaji Bhaskar, PhD, bhaskarm@tsu.edu
Role: Sample sorting, sample preparation for chemical analysis. Chemical analysis using the Total carbon nitrogen machine. Geo-spatial analysis of the data using ArcGIS. Data analysis and interpretation.