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Ecology Of Phragmites Australis And Responses To Tidal Restoration, Randolph Chambers, Laura A. Meyerson, Kimberly L. Dibble

Randolph Chambers

Tidal Marsh Restoration provides the scientific foundation and practical guidance necessary for coastal zone stewards to initiate salt marsh tidal restoration programs. The book compiles, synthesizes, and interprets the current state of knowledge on the science and practice of salt marsh restoration, bringing together leaders across a range of disciplines in the sciences (hydrology, soils, vegetation, zoology), engineering (hydraulics, modeling), and public policy, with coastal managers who offer an abundance of practical insight and guidance on the development of programs.

The book is an essential work for managers, planners, regulators, environmental and engineering consultants, and others engaged in planning, designing, …

Modeling The Effects Of Crab Potting And Road Traffic On A Population Of Diamondback Terrapins, Sarah Gilligand, Randolph Chambers

Randolph Chambers

No abstract provided.

The Influence Of Recreational Crabbing Regulations On Diamondback Terrapin By-Catch, Randolph Chambers

Randolph Chambers

Malaclemys terrapin terrapin (Northern Diamondback Terrapin) is susceptible to drowning in commercial-style pots used for the Callinectes sapidus (Blue Crab) fishery. Regulations to reduce by-catch mortality vary by state. We compared three different regulatory strategies with respect to crab catch and their relative effectiveness at reducing terrapin by-catch. To mimic their possible use by recreational crabbers, we grouped and fished together ten unbaited crab pots with no by-catch reduction devices (BRDs), ten with large BRDs, and ten with small BRDs in a tidal creek in southeastern Virginia. Over 24 sampling days, the total legal crab catch (crabs ≥ 12.7 cm) …

Use Of Esi-Fticr-Ms To Characterize Dissolved Organic Matter In Headwater Streams Draining Forest-Dominated And Pasture-Dominated Watersheds, Randolph Chambers

Randolph Chambers

Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS) has proven to be a powerful technique revealing complexity and diversity of natural DOM molecules, but its application to DOM analysis in grazing-impacted agricultural systems remains scarce. In the present study, we presented a case study of using ESI-FTICR-MS in analyzing DOM from four headwater streams draining forest- or pasture-dominated watersheds in Virginia, USA. In all samples, most formulas were CHO compounds (71.8–87.9%), with other molecular series (CHOS, CHON, CHONS, and CHOP (N, S)) accounting for only minor fractions. All samples were dominated by molecules falling in the lignin-like region …

Photochemical And Microbial Alteration Of Dissolved Organic Matter In Temperate Headwater Streams Associated With Different Land Use, Randolph Chambers

Randolph Chambers

Photochemical and microbial transformations of DOM were evaluated in headwater streams draining forested and human‐modified lands (pasture, cropland, and urban development) by laboratory incubations. Changes in DOC concentrations, DOC isotopic signatures, and DOM fluorescence properties were measured to assess the amounts, sources, ages, and properties of reactive and refractory DOM under the influence of photochemistry and/or bacteria. DOC in streams draining forest‐dominated watersheds was more photoreactive than in streams draining mostly human‐modified watersheds, possibly due to greater contributions of terrestrial plant‐derived DOC and lower amounts of prior light exposure in forested streams. Overall, the percentage of photoreactive DOC in stream …

Stormwater Runoff Drives Viral Community Composition Changes In Inland Freshwaters, Randolph Chambers

Randolph Chambers

Storm events impact freshwater microbial communities by transporting terrestrial viruses and other microbes to freshwater systems, and by potentially resuspending microbes from bottom sediments. The magnitude of these impacts on freshwater ecosystems is unknown and largely unexplored. Field studies carried out at two discrete sites in coastal Virginia (USA) were used to characterize the viral load carried by runoff and to test the hypothesis that terrestrial viruses introduced through stormwater runoff change the composition of freshwater microbial communities. Field data gathered from an agricultural watershed indicated that primary runoff can contain viral densities approximating those of receiving waters. Furthermore, viruses …

Integrated Carbon Budget Models For The Everglades Terrestrial-Coastal-Oceanic Gradient: Current Status And Needs For Inter-Site Comparisons., Randolph Chambers

Randolph Chambers

Recent studies suggest that coastal ecosystems can bury significantly more C than tropical forests, indicating that continued coastal development and exposure to sea level rise and storms will have global biogeochemical consequences. e Florida Coastal Everglades Long Term Ecological Research (FCE LTER) site provides an excellent subtropical system for examining carbon (C) balance because of its exposure to historical changes in freshwater distribution and sea level rise and its history of significant long-term carbon-cycling studies. FCE LTER scientists used net ecosystem C balance and net ecosystem exchange data to estimate C budgets

for riverine mangrove, freshwater marsh, and seagrass meadows, …

Occurrence And Distribution Of The Freshwater Amphipodsgammarus Pseudolimnaeus And Gammarus Fasciatus Insoutheastern Virginia, Randolph Chambers

Randolph Chambers

The freshwater amphipod, Gammarus fasciatus, and a population that keys to Gammarus pseudolimnaeusare broadly sympatric in southeastern Virginia. By documenting the successful formation of pre-copulatory mate-guarding pairs between individuals collected from Virginia and New York, we confirmed the occurrence of a G. pseudolimnaeus population strongly disjunct from the previously described range in the Mississippi and St. Lawrence River drainage basins. Gammarus pseudolimnaeus appears restricted to high-quality, spring-fed streams that occur at low density across an increasingly fragmented natural landscape in Virginia. Gammarus fasciatus, however, occurs in lakes and streams of developed landscapes that typically are more degraded, …

Selective Feeding On Nutrient-Rich Particles By Gizzard Shad Dorosoma Cepedianum Does Not Involve Mechanical Sorting, Paul D. Heideman, Jonathan Worth Holley, Randolph Chambers, Laurie Sanderson

Randolph Chambers

Previous field and laboratory studies have concluded that suspension-feeding detritivorous fish such as gizzard shad Dorosoma cepedianum selectively ingest nutrient-rich particles using either mechanical sorting within the oropharyngeal cavity or behavioral selectivity within the environment, but none have distinguished between these hypothesized selection mechanisms. To determine whether mechanical selectivity occurs within the oropharyngeal cavity, gizzard shad were fed particles of standardized size but different carbon and nitrogen content in homogeneous particle suspensions vs. non-homogeneous particle distributions. By comparing foregut and epibranchial organ contents with the particles available in a homogeneous suspension, we demonstrated that the fish did not use mechanical …

Hydrologic And Chemical Control Of Phragmites Growth In Tidal Marshes Of Sw Connecticut, Usa, Randolph Chambers

Randolph Chambers

We compared hydrology and porewater chemistry along transects in 3 tidal marshes vegetated by Spartina alterniflora and by the invasive species Phragmites australis. Relative to the Phragmites zone, the S. alterniflora zone occurred at lower tidal elevations in all 3 marshes and was characterized by greater depth of flooding and shorter periods of water-table drawdown below the soil surface. Penetration by Phragmites into the S. alterniflora zone appeared to be limited by extensive soil saturation at the leading edge of Phragmites growth. This mixed-species zone occurred at the intersection of the low-tide groundwater table with the soil surface and …

Characteristics Of Vesicomyid Clams And Their Environment At The Blake Ridge Cold Seep, South Carolina, Usa, Randolph Chambers

Randolph Chambers

Spatial distributions and patchiness of dominant megafaunal invertebrates in deep-sea seep environments may indicate heterogeneities in the flux of reduced chemical compounds. At the Blake Ridge seep off South Carolina, USA, the invertebrate assemblage includes dense populations of live vesicomyid clams (an undescribed species) as well as extensive clam shell beds (i.e. dead clams). In the present study, we characterized clam parameters (density, size-frequency distribution, reproductive condition) in relation to sulfur chemistry (sulfide and sulfate concentrations and isotopic compositions, pyrite and elemental sulfur concentrations) and other sedimentary metrics (grain size, organic content). For clams >5 mm, clam density was highest …

Homing Behavior Of Musk Turtles In A Virginia Lake, Randolph Chambers

Randolph Chambers

For nine weeks during the summer of 2002, a mark and recapture technique was used to study homing behavior of Musk Turtles (Sternotherus odoratus) living in Lake Matoaka, VA. During the first three weeks of the study, 119 turtles (83 male, 36 female) were captured using unbaited crabpots, then marked and displaced from the site of capture. Turtles were displaced 100 m across open water 4 m deep, 520 m along the same shore, or 550 m across open water. For the last six weeks of the study, 110 turtles (65 males, 45 females) were captured and released with no …

Dissolved And Particulate Organic Carbon Fluxes From An Agricultural Watershed During Consecutive Tropical Storms, Randolph Chambers

Randolph Chambers

Low‐frequency high‐magnitude hydrologic events mobilize a disproportionate amount of dissolved organic carbon (DOC) from watersheds, but few studies measure the role of extreme storms in exporting organic carbon from croplands. We use high‐resolution measurements of storm runoff to quantify DOC and particulate organic carbon (POC) fluxes from an agricultural field during consecutive tropical storms that delivered 41 cm of rainfall to the Virginia Coastal Plain. Over a 2 week period, we measured exports of 22 kg DOC ha−1 and 11.3 kg POC ha−1. Ultraviolet absorbance measurements indicate that the aromatic DOC fraction systematically increased as plant‐derived aliphatic carbon was depleted …