MRI: Instrumentation for the Chemical and Biological Characterization of Factors Affecting the Distribution and Phytoremediation of Seagrasses in Coastal Bays and Estuaries

Texas A&M University Corpus Christi, Corpus Christi TX

Investigators

Abstract

A grant has been awarded to Dr. Patrick Larkin, Dr. Kirk Cammarata, Dr. Eugene Billiot, Dr. Feri Billiot, Dr. Patrick Louchouarn and Dr. Mark Morvant at Texas A&M University-Corpus Christi to Acquire instrumentation to study the environmental factors affecting the distribution of seagrasses along the south Texas Gulf coast. The instruments to be acquired include (1) a genetic analyzer for DNA sequencing and molecular marker analysis, (2) an ultracentrifuge for the preparation of subcellular fractions, organelle DNA, proteins and peptides (3) a capillary electrophoresis system for the analysis of environmental pollutants such as herbicides, organometallic compounds and inorganic ions and (4) a freeze dryer for the preparation of sediment and plant tissues for analysis. The goals and scope of this research will be to 1) assess the distribution, heterogeneity and flow of genes among seagrass meadows along the south Texas gulf coast; 2) advance our understanding of the significance of organic and metal pollutants in our unique environment; and 3) develop plant-based systems (or microcosms) which can specifically detoxify contaminants in soil or water. Studies will include the analysis of seagrass species (Halodule beaudetteii, Halophila engelmannii, Cymodocea filiformis, Thalassia testudinum, and Ruppia maritima) for genetic diversity and gene flow among populations highly impacted by agricultural, recreational and industrial activity. Analysis of genetic diversity will be undertaken by the development of molecular markers, direct DNA sequencing and statistical analysis. Seagrasses and associated aquatic plants will be studied to assess their ability for the bioaccumulation and/or detoxification of environmental contaminants. In particular, mechanistic studies will utilize capillary electrophoresis technology to characterize the occurrence of relevant chelators in study plants. Parameters to be identified and quantified include metal concentrations, organic acids, amino acids, phytochelatins, and transport proteins. We also wish to study how plants and seagrasses in particular, respond to/remove organic pollutants, since a number of such contaminants exist along the Texas gulf coast's unique environment. We would like to: 1) quantify hydrophobic organic carbons (HOC's) in aquatic/wetland plant tissues to determine partitioning and biological fate, and 2) compare HOCs in rhizosphere vs. non-rhizosphere sediments for various plants. Our research proposes to answer many questions concerning habitat requirements, potential mechanisms of pollutant phytoremediation and the importance of genetics for conservation, propagation and establishment of seagrass and associated aquatic plant beds.