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No-Net-Loss Not Met For Nutrient Function In Freshwater Marshes: Recommendations For Wetland Mitigation Policies, Katie Hossler, Virginie Bouchard, M. Siobhan Fennessy, Serita D. Frey, Evelyn Anemaet, Ellen Herbert Jul 2011

No-Net-Loss Not Met For Nutrient Function In Freshwater Marshes: Recommendations For Wetland Mitigation Policies, Katie Hossler, Virginie Bouchard, M. Siobhan Fennessy, Serita D. Frey, Evelyn Anemaet, Ellen Herbert

Faculty Publications

Wetlands provide many important services throughout the world, with an estimated economic value that, in comparison to other ecosystems, far exceeds their relatively small global extent. In recognition of their importance, both national and international regulations exist to protect the world's remaining wetlands. Of growing interest is the “no-net-loss” policy which permits unavoidable destruction of wetlands if compensated by restoration of degraded wetlands or creation of new wetlands. The fundamental assumption of no-net-loss is that wetlands can be created which function equivalently to natural wetlands. One integral function that wetlands perform is cycling of carbon, nitrogen and phosphorus. Here we …


Spring Hydrology Of Colorado Bend State Park, Central Texas, Kevin W. Stafford, Melinda G. Shaw-Faulkner, Jessica L. Deleon Apr 2011

Spring Hydrology Of Colorado Bend State Park, Central Texas, Kevin W. Stafford, Melinda G. Shaw-Faulkner, Jessica L. Deleon

Faculty Publications

Karst development in Ellenburger carbonates near Colorado Bend State Park in central Texas exhibits complex polygenetic origins, with porosity development dominated by an early hypogene phase that has subsequently been overprinted to varying degrees by epigene processes. Quarterly physicochemical and continuous thermal monitoring analyses of eight springs in the study area indicate that modern groundwater flow paths are highly variable. Springs exhibit patterns that range from shallow, distributed recharge into diffuse-flow dominated systems, to focused recharge into well-connected conduit systems, to deep-circulation systems that equilibrate with bedrock. All springs, except Sulphur Spring, exhibit physicochemical characteristics indicative of proximal epigenic groundwater …


Measurements And Three-Dimensional Modeling Of Nearshore Circulation On A South Carolina Beach, Nirnimesh Kumar, George Voulgaris, John C. Warner Apr 2011

Measurements And Three-Dimensional Modeling Of Nearshore Circulation On A South Carolina Beach, Nirnimesh Kumar, George Voulgaris, John C. Warner

Faculty Publications

A numerical modeling system for simulating nearshore surf zone conditions and tidal processes is presented and evaluated with in situ data. The modeling system is comprised of the Regional Ocean Modeling System (ROMS v 3.0), a three-dimensional numerical ocean model, coupled with Simulating Waves Nearshore (SWAN), a spectral wave propagation model. The system has been modified with a new vertical distribution of radiation stress terms for applications in very shallow waters. The model performance is evaluated by comparing simulations to hydrodynamic data (wave height, direction, longshore and cross-shore currents) collected in the surf zone in northern South Carolina, U.S. Model …


Two-Stepping Into The Icehouse: East Antarctic Weathering During Progressive Ice-Sheet Expansion At The Eocene–Oligocene Transition, Howie Scher, Steven M. Bohaty, James C. Zachos, Margaret L. Delaney Apr 2011

Two-Stepping Into The Icehouse: East Antarctic Weathering During Progressive Ice-Sheet Expansion At The Eocene–Oligocene Transition, Howie Scher, Steven M. Bohaty, James C. Zachos, Margaret L. Delaney

Faculty Publications

In conjunction with increasing benthic foraminiferal 18O values at the Eocene–Oligocenetransition (EOT; ca. 34 Ma), coarse-grained ice-rafted debris (IRD; >425 μm) appearsabruptly alongside fossil fi sh teeth with continentally derived neodymium (Nd) isotope ratios( Nd) in Kerguelen Plateau (Southern Ocean) sediments. Increased Antarctic weathering fl ux,as inferred from two steps to less radiogenic Nd values, coincides with two steps in benthicforaminiferal 18O values. These results indicate that two distinct surges of weathering weregenerated by East Antarctic ice growth during the EOT. Weathering by ice sheets during aprecursor glaciation at 33.9 Ma did not produce signifi cant IRD accumulation during the …


Detecting Toxic Diatom Blooms From Ocean Color And A Regional Ocean Model, Clarissa R. Anderson, Raphael M. Kudela, Claudia R. Benitez-Nelson, Emily Sekula-Wood, Christopher T. Burrell, Yi Chao, Gregg Langlois, Jo Goodman, David A. Siegel Feb 2011

Detecting Toxic Diatom Blooms From Ocean Color And A Regional Ocean Model, Clarissa R. Anderson, Raphael M. Kudela, Claudia R. Benitez-Nelson, Emily Sekula-Wood, Christopher T. Burrell, Yi Chao, Gregg Langlois, Jo Goodman, David A. Siegel

Faculty Publications

[1] An apparent link between upwelling‐related physical signatures, macronutrients, and toxic diatom blooms in the various “hotspots” throughout California has motivated attempts to forecast harmful algal blooms (HABs) as a function of select environmental variables. Empirical models for predicting toxic Pseudo‐nitzschia blooms in one such region, the Santa Barbara Channel (SBC), are tested in a nowcast mode using predictions based on merging data from MODIS ocean color geophysical products and the Regional Ocean Modeling System (ROMS) applied to the Southern California Bight. Thresholds for each model generate event forecasts. Spatially‐explicit, monthly HAB maps are compared to shipboard observations and California …


A Comparative Integrated Geophysical Study Of Horseshoe Chimney Cave, Colorado Bend State Park, Texas, Wesley A. Brown, Kevin W. Stafford, Melinda G. Shaw-Faulkner, Andy Grubbs Jan 2011

A Comparative Integrated Geophysical Study Of Horseshoe Chimney Cave, Colorado Bend State Park, Texas, Wesley A. Brown, Kevin W. Stafford, Melinda G. Shaw-Faulkner, Andy Grubbs

Faculty Publications

An integrated geophysical study was performed over a known cave in Colorado Bend State Park (CBSP), Texas, where shallow karst features are common within the Ellenberger Limestone. Geophysical survey such as microgravity, ground penetrating radar (GPR), direct current (DC) resistivity, capacitively coupled (CC) resistivity, induced polarization (IP) and ground conductivity (GC) measurements were performed in an effort to distinguish which geophysical method worked most effectively and efficiently in detecting the presence of subsurface voids, caves and collapsed features. Horseshoe Chimney Cave (HCC), which is part of a larger network of cave systems, provides a good control environment for this research. …