Nowlin, Weston H.Abuzeineh, Alisa A.2011-12-092011-12-092011-12Abuzeineh, A. A. (2011). <i>Cross system Transport of organic matter and contaminants in semi-arid and arid lotic ecosystems</i> (Unpublished dissertation). Texas State University-San Marcos, San Marcos, Texas.https://hdl.handle.net/10877/2436Externally-derived resources are important for the dynamics and stability of the systems involved, especially for recipient systems. In addition, environmental scientists have expanded this concept of cross-ecosystem resource subsidies to include the transfer of bioaccumulating contaminants across ecosystem boundaries. The aim of my research was to examine the relative contribution of autochthonous and allochthonous OM sources to fish communities in the Rio Grande/Rio Bravo del Norte drainage in Texas. I additionally assessed patterns in the potential movement of Hg from streams to riparian consumers. My research focused on three main areas: (1) the cycling of organic matter and contaminants within and across aquatic-terrestrial interfaces, (2) landscape- and regional-level parameters that influence macroinvertebrate assemblages at local and landscape spatial scales, and (3) the effect of environmental processes on aquatic communities using stable isotope-derived ecometrics. The information gathered from these studies provides greater understanding of the movements of OM and contaminants across local and landscape level environmental gradients.Text181 pages1 file (.pdf)enAllochthonous subsidiesMercuryRio GrandeStable isotopesCommunity-wide metricsStream ecologyArid regions ecology--Rio Grande (Colo.-Mexico and Tex.)Arid regions--Research--Rio Grande (Colo.-Mexico and Tex.)Dissertation