Semester of Graduation
Summer 2024
Degree
Master of Science (MS)
Department
School of Renewable Natural Resources
Document Type
Thesis
Abstract
Globally, woody plant encroachment into grassland and savanna ecosystems impacts the hydrological functions of grasslands and associated wetlands. In the coastal tallgrass prairie of Texas, encroachment of woody plants has altered vegetation structure, but the hydrological impacts are poorly understood. In this study, I evaluated and quantified how woody plant encroachment affects hydrological processes on the pimple mounds and inter-mound freshwater marsh, including precipitation partitioning, infiltration in the vadose zone, groundwater recharge, and water volume in the inter-mound marsh. I randomly selected three pimple mounds with woody plants and three pimple mounds with tallgrass w to quantify hydrologic processes. The canopy of woody plants intercepted 11% more precipitation than tallgrass during rainfall, but The difference in canopy interception between the two vegetation types increased when the leaf area of tallgrass was low during the nongrowing season. In the vadose zone, woody plants significantly reduced the soil moisture response during rainfall at the upper soil layer but enhanced infiltration to the subsoil layer. During the wet season, woody plants and tallgrass both reduced the water table elevation under the pimple mounds compared to surface water elevation in the inter-mound marsh. The water table elevation under woody plants was not consistently lower than tallgrass, and woody plants on some pimple mounds had more groundwater recharge from precipitation than tallgrass. However, during the wet season, woody plants on pimple mounds with potentially high transpiration reduced the water volume in the freshwater marsh on coastal tallgrass prairie. My results provide insights into the hydrological processes altered by woody plant encroachment. These results will guide the woody plant management practices because woody plant removal increased water volume in the inter-mound marsh, which is important for wintering waterbirds on the Texas coast.
Date
7-16-2024
Recommended Citation
Guo, Zhiwei, "THE HYDROLOGICAL IMPACTS OF WOODY PLANT ENCROACHMENT ON COASTAL TALLGRASS PRAIRIE OF TEXAS" (2024). LSU Master's Theses. 6010.
https://repository.lsu.edu/gradschool_theses/6010
Committee Chair
Sammy King
DOI
https://doi.org/10.31390/gradschool_theses.6010