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J. T. Reel

Publications and source records attributed to J. T. Reel.

6 recordsLinked to original sources
USGS2007

Vegetative resistance to flow in South Florida: Summary of vegetation sampling in Taylor Slough, Everglades National Park, September 1997–July 1998

The U.S. Geological Survey is one of many agencies providing scientific support to the effort to restore the South Florida Everglades. In September and November 1997 and July 1998, vegetation was sampled at selected sites in the Everglades as part of a study to quantify vegetative resistance to flow. The objectives of the vegetation sampling are (1) to provide detailed information on species composition, vegetation characteristics, and biomass for quantification of the effect of vegetation on water flow, and (2) to use these data in the future to infer flow resistance from vegetation information. Forty-two vegetation quadrats were sampled in Taylor Slough to determine the number and width of stems and leaves and the biomass of live and dead standing sawgrass, rush, and other plants, and the biomass of dead litter and periphyton. The samples were grouped into ten vegetation classes based on species composition and total biomass minus periphyton biomass.

Florida↗
USGS2001

Investigations of the availability and survival of submersed aquatic vegetation propagules in the tidal Potomac River

The establishment of submersed aquatic vegetation (SAV) at unvegetated sites in the freshwater tidal Potomac River was limited primarily by factors other than propagule availability. For two years, traps were used to quantify the amount of plant material reaching three unvegetated sites over the growing season. The calculated flux values provided a gross estimate of the flux of propagules that could potentially survive if other site factors were suitable. The mean flux of Hydrilla verticillata and all other species (≥0.01 gdw m −2 d −1 ) appeared sufficient to favor the establishment of vegetation, particularly considering the high viability (70–100%) of whole plants and fragments under controlled conditions. However, median water clarity values (i.e., for light attenuation, Secchi depth, total suspended solids, and chlorophyll a ) were below SAV restoration goals at all unvegetated sites. Additionally, sediments from unvegetated sites showed a potential for nitrogen limitation of the growth of H. verticillata . Our findings support the hypothesis that in the tidal Potomac River, water clarity and nutrient (especially nitrogen) levels in sediment are key to plant community establishment.

Virginia↗
USGS1999

Chesapeake Bay habitat criteria scores and the distribution of submersed aquatic vegetation in the tidal Potomac River and Potomac Estuary, 1983-1997

The Chesapeake Bay Program has identified habitat requirements for the restoration of submersed aquatic vegetation (SAV) in the Chesapeake Bay estuary and tidal reaches of contributing river systems conditioned on the salinity regime of a specific location. The tidal Potomac River and Potomac Estuary is an important component of the Chesapeake Bay system to which these requirements can be applied. The SAV habitat requirements are formulated as threshold criteria that certain critical water-quality characteristics must satisfy during the SAV growing season. A multivariate scoring system based on these criteria was developed in order to synopsize water quality conditions during the 1983-1997 SAV growing seasons. Chesapeake Bay habitat criteria scores are displayed relative to annual SAV coverage for each Potomac River and Potomac Estuary segment. It is seen that although there is some correspondence in the inter-annual expansion or contraction of SAV coverage and compliance with Chesapeake Bay SAV habitat criteria, individual criteria provide neither necessary nor sufficient conditions to explain inter-annual dynamics of SAV coverage, especially in the Potomac Estuary.

Open-File Report↗
USGS1998

Correlations among seasonal water quality, discharge, weather, and coverage by submersed aquatic vegetation in the tidal Potomac River and Potomac Estuary, 1983-96

The U.S. Geological Survey has been cooperating with other scientists under the auspices of the Interstate Commission on the Potomac River Basin to utilize existing data from the tidal Potomac River and Estuary for investigating linkages among living resources (primary producers, consumers) and abiotic components of the environment. Because the distribution and abundance of submersed aquatic vegetation in the tidal Potomac River and Estuary are controlled largely by light availability, the first step in investigating linkages with submersed aquatic vegetation is to examine the correlations that exist among vegetative cover, discharge, water quality and weather, all of which can affect light availability directly or indirectly. Growing season (April-October), spring (April-June), and summer (July-August) correlations are presented along with figures demonstrating the significant relationships among variables.

Open-File Report↗