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Research about Tampa Bay, Florida

Source-linked reports with geographic coverage including Tampa Bay, Florida.

11 recordsLinked to original sources
USGS2012

An investigation of submarine groundwater—borne nutrient fluxes to the west Florida shelf and recurrent harmful algal blooms

A cross‐shelf, water‐column mass balance of radon‐222 ( 222 Rn) provided estimates of submarine groundwater discharge (SGD), which were then used to quantify benthic nutrient fluxes. Surface water and groundwater were collected along a shore‐normal transect that extended from Tampa Bay, Florida, across the Pinellas County peninsula, to the 10‐m isobath in the Gulf of Mexico. Samples were analyzed for 222 Rn and radium‐223,224,226 ( 223,224,226 Ra) activities as well as inorganic and organic nutrients. Cross‐shore gradients of 222 Rn and 223,224,226 Ra activities indicate a nearshore source for these isotopes, which mixes with water characterized by low activities offshore. Radon‐based SGD rates vary between 2.5 and 15 cm d −1 proximal to the shoreline and decrease offshore. The source of SGD is largely shallow exchange between surface and pore waters, although deeper groundwater cycling may also be important. Enrichment of total dissolved nitrogen and soluble reactive phosphorus in pore water combined with SGD rates results in specific nutrient fluxes comparable to or greater than estuarine fluxes from Tampa Bay. The significance of these fluxes to nearshore blooms of Karenia brevis is highlighted by comparison with prescribed nutrient demands for bloom maintenance and growth. Whereas our flux estimates do not indicate SGD and benthic fluxes as the dominant nutrient source to the harmful algal blooms, SGD‐derived loads do narrow the deficit between documented nutrient supplies and bloom demands.

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USGS2012

Digital recovery of 19th century surveys in Tampa Bay, Florida: Topographic charts and Public Land Surveys

Recovery of historic data to a digital setting adresses the need for data integration through time, bridging technical gaps and differences. The goal of this study was to evaluate a marsh-to-mangrove conversion spanning 125 years and the implications for present coastal-resource management (Yates and others, 2011; Raabe and others, 2012). The U.S. Geological Survey in St. Petersburg, Fla., georectified and digitized 1870s T-sheets at four Tampa Bay locations that still supported coastal wetlands in 2000 (table 1). Nineteenth century Public Land Surveys of Township and Range lines were also digitized for each site, as a secondary data source to verify historic landscape features (table 2).

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USGS2011

Integrating science and resource management in Tampa Bay, Florida

Tampa Bay is recognized internationally for its remarkable progress towards recovery since it was pronounced "dead" in the late 1970s. Due to significant efforts by local governments, industries and private citizens throughout the watershed, water clarity in Tampa Bay is now equal to what it was in 1950, when population in the watershed was less than one-quarter of what it is today. Seagrass extent has increased by more than 8,000 acres since the mid-1980s, and fish and wildlife populations are increasing. Central to this successful turn-around has been the Tampa Bay resource management community's long-term commitment to development and implementation of strong science-based management strategies. Research institutions and agencies, including Eckerd College, the Florida Wildlife Commission Fish and Wildlife Research Institute, Mote Marine Laboratory, National Oceanic and Atmospheric Administration, the Southwest Florida Water Management District, University of South Florida, U.S. Environmental Protection Agency, U.S. Geological Survey, local and State governments, and private companies contribute significantly to the scientific basis of our understanding of Tampa Bay's structure and ecological function. Resource management agencies, including the Tampa Bay Regional Planning Council's Agency on Bay Management, the Southwest Florida Water Management District's Surface Water Improvement and Management Program, and the Tampa Bay Estuary Program, depend upon this scientific basis to develop and implement regional adaptive management programs. The importance of integrating science with management has become fully recognized by scientists and managers throughout the region, State and Nation. Scientific studies conducted in Tampa Bay over the past 10–15 years are increasingly diverse and complex, and resource management programs reflect our increased knowledge of geology, hydrology and hydrodynamics, ecology and restoration techniques. However, a synthesis of this research and its integration into resource management has not been prepared for Tampa Bay since the mid-1980s. The need for an up-to-date synthesis of Tampa Bay science and management has resulted in the production of this document. The U.S. Geological Survey recently completed a 5-year Tampa Bay Integrated Science Study, and the Tampa Bay Estuary Program updated the Comprehensive Conservation and Management Plan for Tampa Bay in 2006. These efforts build upon results of the many research and management studies and programs summarized here.

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USGS2007

Sea level rise in Tampa Bay

Understanding relative sea level (RSL) rise during periods of rapid climatic change is critical for evaluating modern sea level rise given the vulnerability of Antarctic ice shelves to collapse [ Hodgson et al, 2006], the retreat of the world's glaciers [ Oerlemans, 2005], and mass balance trends of the Greenland ice sheet [ Rignot and Kanagaratnam, 2006]. The first-order pattern of global sea level rise following the Last Glacial Maximum (LGM, ∼21,000 years ago) is well established from coral [ Fairbanks, 1989], continental shelf [ Hanebuth et al, 2000], and other records [ Pirazzoli, 2000] and has been integrated into a global ICE-5G model of glacio-isostatic adjustment (GIA) [ Peltier, 2004]. However, uncertainty introduced by paleo water depth of sea level indicators, radiocarbon chronology (i.e., reservoir corrections for marine shell dates), postglacial isostatic adjustment, and other processes affecting vertical position of former shorelines produces scatter in RSL curves, limiting our knowledge of sea level rise during periods of rapid glacial decay. One example of this limitation is the Gulf of Mexico/Florida region where, despite decades of study, RSL curves produce two conflicting patterns: those showing progressive submergence with a decelerating rate during the past 5000 years [ Scholl et al, 1969] and those showing high sea level during the middle of the Holocene [ Blum et al, 2001; Balsillie and Donoghue, 2004], where the Holocene represents a geologic epoch that extends from about 10,000 years ago to present times. This discrepancy is emblematic of the uncertainty surrounding Holocene sea level and ice volume history in general.

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USGS2007

Tampa Bay as a model estuary for examining the impact of human activities on biogeochemical processes: an introduction

Tampa Bay is a shallow, Y-shaped coastal embayment that is located along the center of the Florida Platform – an expansive accumulation of Cretaceous–Tertiary shallow-water carbonates and evaporites that were periodically exposed during glacio–eustatic sea level fluctuations. As a consequence, extensive karstification likely had a controlling impact on the geologic evolution of Tampa Bay. Despite its large aerial size (∼ 1000 km 2 ), Tampa Bay is relatively shallow (mean depth = 4 m) and its watershed (6700 km 2 ) is among the smallest in the Gulf of Mexico. About 85% of all freshwater inflow (mean = 63 m 3 s -1 ) to the bay is carried by four principal tributaries (Orlando et al., 1993). Groundwater makes up an important component of baseflow of these coastal streams and may also be important in delivering nutrients and other constituents to the bay proper by submarine groundwater discharge.

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USGS2007

Effects of ghost shrimp on zinc and cadmium in sediments from Tampa Bay, FL

This study investigated the effects that ghost shrimp have on the distribution of metals in sediment. We measured levels of HNO 3 -extractable zinc and cadmium in surface sediment, in ghost shrimp burrow walls and in sediment ejected by the ghost shrimp from their burrows, at five sandy intertidal sites in Tampa Bay. Ghost shrimp densities and their rate of sediment ejection were also quantified, as were sediment organic content and silt + clay content. Densities of ghost shrimp ( Sergio trilobata and Lepidophthalmus louisianensis ) averaged 33/m 2 at our sites, and they ejected sediment at an average rate of 28 g/burrow/day. Levels of both Zn and Cd were significantly higher in burrow walls than in surface sediments. Sediment ejected by the shrimp from their burrows had elevated levels of Zn (relative to surface sediments) at one of the sites. Sediment organic content and silt + clay content were higher in burrow-wall sediments than in ejected sediment, which in turn tended to have values above those of surface sediments. Differences in levels of HNO 3 -extractable Zn and Cd among sediment types may be a consequence of these sediments differing in other physiochemical characteristics, though the differences in metal levels remained statistically significant for some sites after correcting for differences in organic content and silt + clay content. We conclude that the presence of ghost shrimp burrows contributes to spatial heterogeneity of sedimentary metal levels, while the ghost shrimp bioturbation results in a significant flux of metals to the sediment surface and is expected to decrease heterogeneity of metal levels in sedimentary depth profiles.

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USGS2004

Development, evaluation, and application of sediment quality targets for assessing and managing contaminated sediments in Tampa Bay, Florida

Tampa Bay is a large, urban estuary that is located in west central Florida. Although water quality conditions represent an important concern in this estuary, information from numerous sources indicates that sediment contamination also has the potential to adversely affect aquatic organisms, aquatic-dependent wildlife, and human health. As such, protecting relatively uncontaminated areas of the bay from contamination and reducing the amount of toxic chemicals in contaminated sediments have been identified as high-priority sediment management objectives for Tampa Bay. To address concerns related to sediment contamination in the bay, an ecosystem-based framework for assessing and managing sediment quality conditions was developed that included identification of sediment quality issues and concerns, development of ecosystem goals and objectives, selection of ecosystem health indicators, establishment of metrics and targets for key indicators, and incorporation of key indicators, metrics, and targets into watershed management plans and decision-making processes. This paper describes the process that was used to select and evaluate numerical sediment quality targets (SQTs) for assessing and managing contaminated sediments. These SQTs included measures of sediment chemistry, whole-sediment and pore-water toxicity, and benthic invertebrate community structure. In addition, the paper describes how the SQTs were used to develop site-specific concentration-response models that describe how the frequency of adverse biological effects changes with increasing concentrations of chemicals of potential concern. Finally, a key application of the SQTs for defining sediment management areas is discussed.

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USGS2001

Tampa Bay, Florida, March 22, 1991

This poster has been prepared for education purposes. Colors are near neutral. Water and swampy areas are blue-black. Healthy plant growth is green. Agricultural fields and areas with low plant growth are pink and beige. Highways, parking lots, and other black surfaces are purple. Beach sand, cleared land, and cement are white or light blue.

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USGS1983

Magnitude and frequency of flooding on small urban watersheds in the Tampa Bay area, west-central Florida

Hydrologic data collected on nine small urban watersheds in the Tampa Bay area of west-central Florida and a method for estimating peak discharges in the study area are described. The watersheds have mixed land use and range in size from 0.34 to 3.45 square miles. Watershed soils, land use, and storm-drainage system data are described. Urban development ranged from a sparsely populated area with open-ditch storm sewers and 19% impervious area to a completely sewered watershed with 61% impervious cover. The U.S. Geological Survey natural-basin and urban-watershed models were calibrated for the nine watersheds using 5-minute interval rainfall data from the Tampa, Florida, National Weather Service rain gage to simulate annual peak discharge for the period 1906-52. A log-Pearson Type III frequency analysis of the simulated annual maximum discharge was used to determine the 2-, 5-, 10-, 25-, 50-, and 100-year flood discharges for each watershed. Flood discharges were related in a multiple-linear regression to drainage area, channel slope, detention storage area, and an urban-development factor determined by the extent of curb and gutter street drainage and storm-sewer system. The average standard error for the regional relations ranged from + or - 32 to + or - 42%. (USGS)

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USGS1983

Assessment of the interconnection between Tampa Bay and the Floridan aquifer, Florida

Factors that control interflow between Tampa Bay and the Floridan aquifer are assessed, both qualitatively and quantitatively, with emphasis on the impact of harbor improvement. Hydrogeologic units underlying the 350-square-mile bay include the surficial-sand aquifer, upper sand and clay confining bed, and limestone of the Floridan aquifer. The surficial aquifer and upper confining bed have been eroded away in several areas along the northern coast of the bay to directly expose the Floridan aquifer to saltwater. There also, the top of the aquifer is, has been, or will be exposed to saltwater in numerous channels dredged in the bay. Saltwater-freshwater relations indicate that the degree of bay-aquifer interconnection decreases from north to south. Saltwater intrusion is occurring along the coast of Tampa Bay, as indicated by reduction or reversal of potentiometric-surface gradients and increasing chloride concentrations in coastal monitoring wells. A computer model of ground-water flow developed for a 97-square-mile area was interrogated under five options of channelization and pumping. Model results indicate that the total impact of channelization upon bay-aquifer interconnection are expected to be small and may be imperceptible when considered over the long term with other unknown changes in climate and development. (USGS)

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