Evaluation of Groundwater Sodium and Sodium Uptake in Taxodium and its Hybrids on Galveston Island, Texas

<p>In September 2008, Hurricane Ike swept through the Gulf of Mexico striking the Gulf Coast, claiming hundreds of lives and causing billions of dollars in damage. The hurricane left behind elevated sea salt concentrations in the soil and groundwater, preventing the unaided return of live oaks and other species to the island. To determine effective ways to ameliorate the elevated Na⁺ concentrations in the soil, eight treatments were applied to the soil and combinations of three species of plants, live oak (<em>Quercus virginiana</em>), hybrid bald cypress (<em>Taxodium</em> ‘<em>T406’</em>), and yellow hibiscus (<em>Hibiscus hamabo</em>) were planted in the plots. These plants were measured for growth in height and diameter over three growing seasons to evaluate the effectiveness of the applied treatments. The <em>Taxodium ‘T406’</em> specimens were then sampled in order to determine elemental concentrations in the foliage across applied treatments. In addition, foliage samples were taken from a series of <em>Taxodium</em> genotypes in order to compare Na⁺ tolerance among the genotypes. In order to evaluate the groundwater characteristics of the study area a three by three grid of piezometers, spaced 25 m apart north by south and 60 m apart east by west, was established and groundwater samples were collected from September 2018 to September 2019. Three Solinst Leveloggers were used in the easternmost piezometers in order to provide a continuous stream of data for each piezometer.</p> <p>Groundwater Na⁺ concentrations were compared with precipitation data to determine if precipitation has a significant impact on elemental concentrations.</p> <p>Plant diameter growth was not significant for diameter among species or treatments, and height growth was also not significant among treatments. <em>Taxodium distichum</em> displayed significantly greater height growth than the other species, possibly due to damage to the other species early in the study. Na⁺ concentrations did not differ significantly among treatments, although among the genotypes there was a significantly higher concentration of Na⁺ in the <em>Taxodium ‘T406’</em> compared to <em>Taxodium distichum</em>. A significant relationship could not be determined between groundwater Na⁺ concentrations and precipitation.</p>

Name thesis:degree_name

Master of Science - Environmental Sciences

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Environmental Science

Year dc:date.available

2020

Author dc:creator

• Morgan, Daniel

Contributors dc:contributor

• Dr. Kenneth Farrish
• Dr. David Creech
• Dr. Kevin Stafford

• Sodium
• Taxodium
• Groundwater
• Salinity
• Hydrology
• Other Environmental Sciences
• Plant Biology

Repository record dc:identifier

https://scholarworks.sfasu.edu/etds/340

OAI identifier oai:identifier

oai:scholarworks.sfasu.edu:etds-1364