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U.S. Geological Survey Science Support Strategy for Biscayne National Park and Surrounding Areas in Southeastern Florida

The U.S. Geological Survey conducts a wide range of research in and around the Biscayne National Park region of southern Florida. This research encompasses the biologic, ecologic, meteorologic, geologic, and hydrologic components of the system, including water-quality analyses, ground-water modeling, hydrogeologic-data collection, ecologic-habitat evaluations, wetlands characterizations, biogeochemistry of ecosystems, and paleo-ecologic analyses. Relevant information is provided herein for researchers and managers interested in the Biscayne Bay area and about current U.S. Geological Survey efforts that address important resource protection and management issues. Specifically, managers and scientists are provided with information on current and recently completed U.S. Geological Survey projects and a sample listing of potential U.S. Geological Survey research projects addressing relevant issues that face the study area.

Open-File Report↗

Aggradation and Degradation of the Palisades Gully Network, 1996 to 2005, with Emphasis on the November 2004 High-Flow Experiment, Grand Canyon National Park, Arizona

This study examines a large drainage network incised into alluvial terraces located along the Colorado River downstream of Palisades Creek in Grand Canyon National Park, Ariz. Gully erosion in the drainage affects archaeological sites found on the wide, relatively flat alluvial terraces. In 1996, 7-d release of 1,274 cubic meters per second of water from Glen Canyon Dam, known as a controlled flood, deposited fine-grained sediment - sand, silt, and clay - in the mouth of the network's largest gully, informally known as south gully. The deposit persisted for several years, but the drainage network steepened in the downstream reaches between 1999 and 2004. A high-flow experiment similar to the 1996 controlled flood was conducted in November 2004. The 2004 experiment was of a lower magnitude and shorter duration compared to the 1996 controlled flood. Topographic surveys were made in the field before, immediately after, and 6 months following the November 2004 experiment, and these measurements were compared to those made in 1996 and in other years. Similar to the response in 1996, fine-grained sediment was deposited in the mouth of the south gully and this mass was largely retained during the 6 months following the 2004 event. The magnitude of deposition in 2004 was nearly two times greater than that resulting from the 1996 controlled flood. We attribute this marked difference to increased accommodation space for deposition in the gully mouth, which was more deeply eroded in 2004 than it was in 1996. The second of the two primary gullies found within the Palisades gully network, the north gully, was largely unaffected by either high flow. Between 1996 and 2005, erosion was primarily confined to the lower reach of the south gully, while the upper reach remained relatively stable. The available data suggest that local base-level changes in the south gully mouth were not linked to the stability of the upstream gully reach. It could not be determined whether temporary base-level increases or maintenance of erosion-control structures were causal factors in limiting erosion in the upstream reaches of the drainage network.

Open-File Report↗

Avian Species Inventory at Manzanar National Historic Site, California - Final Report to the National Park Service

We conducted a baseline inventory for avian species at Manzanar National Historic Site, Inyo County, Calif., from 2002 to 2005. Under the guidelines of the Mojave Network Biological Inventory Program, the primary objectives for this study were to (1) inventory and document the occurrence of avian species at Manzanar, with the goal of documenting at least 90 percent of the species present; (2) provide a geographic information system (GIS)-referenced list of sensitive species occurring at Manzanar that are rare, on Federal or State lists, or otherwise worthy of special consideration; and (3) enter all species data into the National Park Service NPSpecies database. Survey methods included general area searches, variable circular plot point-count censusing, nocturnal surveys, and nest searching. During 13 year-round survey sessions, we documented the occurrence of 132 bird species at Manzanar and confirmed breeding by 19 of these. Based on our findings, as well as review of the literature and searches for records of species occurrence, we estimate inventory completeness for regularly occurring bird species at Manzanar to be near 90 percent. No sensitive species on Federal or State lists were found. The distribution and relative abundance of common bird species at this site is now well enough known to begin development of a monitoring protocol for this group.

Open-File Report↗

EAARL topography-Colonial National Historical Park

These Lidar-derived topography maps were produced as a collaborative effort between the U.S. Geological Survey (USGS) Coastal and Marine Geology Program, Florida Integrated Science Center (FISC) St. Petersburg, the National Park Service (NPS) Inventory and Monitoring Program, Northeast Coastal and Barrier Network, and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility. One objective of this research is to create techniques to survey coral reefs, barrier islands, and various nearshore coastal environments for the purposes of geomorphic change studies, habitat mapping, ecological monitoring, change detection, and event assessment. As part of this project, data from an innovative instrument under development at the NASA Wallops Flight Facility, the NASA Experimental Airborne Advanced Research Lidar (EAARL) are being used. This sensor has the potential to make significant contributions in this realm for measuring subaerial and submarine topography wthin cross-environment surveys. High spectral resolution, water-column correction, and low costs were found to be key factors in providing accurate and affordable imagery to coastal resource managers.

Virginia↗

Biological communities and geomorphology of patch reefs in Biscayne National Park, Florida, U.S.A.

Coral reef ecosystem management benefits from continual, quantitative assessment of the resources being managed, plus assessment of factors that affect distribution patterns of organisms in the ecosystem. In this study, we investigated the relationships among physical, benthic, and fish variables in effort to help explain the distribution patterns of ecologically and economically important species on twelve patch reefs within Biscayne National Park (BNP), Florida, U.S.A. We visited 196 randomly-located sampling stations across twelve shallow (< 10m) patch reefs, using SCUBA to conduct our surveys. We measured physical variables (e.g., substratum type), estimated the percent cover of benthic community members (e.g., coral, algae), and counted and estimated mean size for each fish species observed. We also used high-density bathymetric data collected remotely via airborne laser surveying (Experimental Advanced Airborne Research Lidar (EAARL)) to calculate rugosity (bumpiness) of the reef habitat. Here we present our findings visually by graphing our quantitative community and physical structure data simultaneously in a GIS map format. You will see that biological organisms arrange themselves on each patch reef in a non-random manner. For example, many species of fish prefer to locate themselves in areas of the reef where the rugosity index is high. Rugose parts of the reef provide them with good hiding places from predators. These maps (and the data used to create them) are permanent records of the status of reef resources found on these twelve patch reefs in BNP as of September, 2003. The survey data found in the shapefile located on this CD product includes benthic percent cover data for algae, coral, encrusting invertebrates, and substratum type, in addition to gorgonian abundance and volume, total fish abundance and species richness, and specific counts for Acanthurids (surgeonfish), Scarids (parrotfish), Lutjanids (snappers), Haemulids (grunts), Serranids (groupers), and Pomacentrids (damselfish).

Florida↗

Transient electromagnetic soundings near Great Sand Dunes National Park and Preserve, San Luis Valley, Colorado (2006 field season)

Time-domain electromagnetic (TEM) soundings were made near Great Sand Dunes National Park and Preserve in the San Luis Valley of southern Colorado to obtain subsurface information of use to hydrologic modeling. Seventeen soundings were made to the east and north of the sand dunes. Using a small loop TEM system, maximum exploration depths of about 75 to 150 m were obtained. In general, layered earth interpretations of the data found that resistivity decreases with depth. Comparison of soundings with geologic logs from nearby wells found that zones logged as having increased clay content usually corresponded with a significant resistivity decrease in the TEM determined model. This result supports the use of TEM soundings to map the location of the top of the clay unit deposited at the bottom of the ancient Lake Alamosa that filled the San Luis Valley from Pliocene to middle Pleistocene time.

Colorado↗

Petrified Forest National Park Invasive Plant Species Survey and Mapping; 2002-2005

We conducted a survey for invasive nonnative plant species at Petrified Forest National Park from 2002 through 2005. The survey employed a unique sampling design consisting of a grid of consecutive one-hectare cells as the sampling units. Our use of predetermined sampling units allowed all observations to be referenced to a fixed area with geographic coordinates that easily transferred to a geographic information system. Our field team surveyed 2,730 sampling units in three select areas for at least 1 year and 879 sampling units for 4 years. During this period we identified 40 different invasive plant species; more than half the invasive plants (22 species) were annual forbs and grasses. Four invasive plant species occurred in 25 percent or more of all sampling units observed in one or more years: Bromus tectorum, Erodium cicutarium, Salsola tragus, and Sisymbrium altissimum. Salsola tragus was the most abundant species in all years and occurred in more than 55 percent of all sampling units surveyed each year.

Open-File Report↗

Relations between environmental and water-quality variables and Escherichia coli in the Cuyahoga River with emphasis on turbidity as a predictor of recreational water quality, Cuyahoga Valley National Park, Ohio, 2008

During the recreational season of 2008 (May through August), a regression model relating turbidity to concentrations of Escherichia coli (E. coli) was used to predict recreational water quality in the Cuyahoga River at the historical community of Jaite, within the present city of Brecksville, Ohio, a site centrally located within Cuyahoga Valley National Park. Samples were collected three days per week at Jaite and at three other sites on the river. Concentrations of E. coli were determined and compared to environmental and water-quality measures and to concentrations predicted with a regression model. Linear relations between E. coli concentrations and turbidity, gage height, and rainfall were statistically significant for Jaite. Relations between E. col i concentrations and turbidity were statistically significant for the three additional sites, and relations between E. col i concentrations and gage height were significant at the two sites where gage-height data were available. The turbidity model correctly predicted concentrations of E. coli above or below Ohio’s single-sample standard for primary-contact recreation for 77 percent of samples collected at Jaite.

Ohio↗

Survey of ungulate abundance on Santa Rosa Island, Channel Islands National Park, California, March 2009

Reliable estimates of elk (Cervus elaphus) and deer (Odocoileus hemionus) abundance on Santa Rosa Island, Channel Islands National Park, California, are required to assess the success of management actions directed at these species. We conducted a double-observer aerial survey of elk on a large portion of Santa Rosa Island on March 19, 2009. All four persons on the helicopter were treated as observers. We used two analytical approaches: (1) with three capture occasions corresponding to three possible observers, pooling the observations from the two rear-seat observers, and (2) with four capture occasions treating each observer separately. Approach 1 resulted in an estimate of 483 elk in the survey zone with a 95-percent confidence interval of 479 to 524 elk. Approach 2 resulted in an estimate of 489 elk in the survey zone with a 95-percent confidence interval of 471 to 535 elk. Approximately 5 percent of the elk groups that were estimated to have been present in the survey area were not seen by any observer. Fog prevented us from collecting double-observer observations for deer as intended on March 20. However, we did count 434 deer during the double-observer counts of elk on March 19. Both the calculated number of elk and the observed number of deer are minimal estimates of numbers of each ungulate species on Santa Rosa Island as weather conditions precluded us from surveying the entire island.

California↗

Holocene core logs and site statistics for modern patch-reef cores: Biscayne National Park, Florida

The bedrock in Biscayne National Park (BNP), a 1,730-square kilometer (km2) region off southeast Florida, consists of Pleistocene (1.8 million years ago (Ma) to 10,000 years ago (ka)) and Holocene (10 ka to present) carbonate rocks (Enos and Perkins, 1977; Halley and others, 1997; Multer and others, 2002). Most of the surficial limestone in BNP, including the islands of the Florida Keys, was formed at ~125 ka during the highstand of marine oxygen-isotope substage 5e, when sea level was approximately 6 meters (m) higher than today (Chappell and Shackleton, 1986; Multer and others, 2002; Lidz and others, 2003; Siddall and others, 2003; Balsillie and Donoghue, 2004). During the substage-5e regression, the entire Florida Platform became exposed. Subaerial exposure lasted for approximately 115,000 years (kyr), which resulted in erosion and enhancement of karst-like features (Lidz and others, 2006). As the Holocene transgression began to flood the Florida shelf ~7 to 6 ka, the bedrock depression under Biscayne Bay began to flood, and Holocene coral and reef debris laid the foundation for the present reef system (Enos and Perkins, 1977; Lighty and others, 1982; Toscano and Macintyre, 2003; Lidz and others, 2006). More than 3,000 patch reefs exist within the BNP boundary. Most contain hermatypic corals of various species such as those belonging to Montastrea, Diploria, Siderastrea, Porites, Acropora, and Agaricia. Patch reefs within BNP have two morphologies: pinnacle and flat top. Experimental Advanced Airborne Research Lidar (EAARL) data collected along the offshore BNP coral reef tract show that these two morphologies are clearly defined both in the high-resolution bathymetry maps produced by the Lidar data and by statistical analyses of the Lidar dataset (Brock and others, 2008). Brock and others (2008) also show that the pinnacle patch reefs are deeper than the more shallow, broad, and flat patch reefs. The control for these two patch-reef morphologies is unclear; however, their shapes may be due to a slightly lowered sea level or a stillstand in the middle-Holocene around 4 ka that caused erosion of the shallower reefs and allowed the deeper reefs to remain unaffected. Lidz and others (2006) have suggested a stillstand around 4 ka that carved a 2.5-kilometer (km)-wide nearshore rock ledge into the seaward side of every island in the Florida Keys. The objectives of this study were to sample living corals to understand the more recent (<200 years) changes in climate and environmental conditions of the area and to investigate the Holocene (in this case, <8,000 years in the Florida Keys) depositional history at progressively deeper patch-reef sites. This report provides statistics for the cores and core sites and a basic lithologic description of these Holocene cores.

Florida↗

Analyses of gas, steam and water samples collected in and around Lassen Volcanic National Park, California, 1975–2002

This report contains physical and chemical data from gas, steam, and water samples collected between July 1975 and September 2002 from locations in and around Lassen Volcanic National Park, California. Data are compiled as tables in Excel spreadsheets and are organized by locale. Most data are keyed to 1 of 107 site codes that are shown on local- and regional-scale maps. Brief descriptions of terminology, sampling, and analytical methods are provided.

California↗

Preliminary Aeromagnetic Map of Joshua Tree National Park and Vicinity, Southern California

This aeromagnetic map of Joshua Tree National Park and vicinity is intended to promote further understanding of the geology and structure in the region by serving as a basis for geophysical interpretations and by supporting geological mapping, water-resource investigations, and various topical studies. Local spatial variations in the Earth's magnetic field (evident as anomalies on aeromagnetic maps) reflect the distribution of magnetic minerals, primarily magnetite, in the underlying rocks. In many cases the volume content of magnetic minerals can be related to rock type, and abrupt spatial changes in the amount of magnetic minerals commonly mark lithologic or structural boundaries. Bodies of mafic and ultramafic rocks tend to produce the most intense magnetic anomalies, but such generalizations must be applied with caution because rocks with more felsic compositions, or even some sedimentary units, also can cause measurable magnetic anomalies. The database includes two ASCII files containing new aeromagnetic data and two ASCII files with point locations of the local maximum horizontal gradient derived from the aeromagnetic data. This metadata file describes the horizontal gradient locations derived from new and existing aeromagnetic data. This aeromagnetic map identifies magnetic features as a basis for geophysical interpretations; the gradients help define the edges of magnetic sources. This database updates geophysical information originally presented in smaller-scale formats and includes detailed aeromagnetic data collected by EON Geosciences, Inc.

Open-File Report↗

Evidence of envronmental change in Rankin basin, Central Florida Bay, Everglades National Park

Analyses of core GLBW601 RL1 collected in Rankin Basin, Florida Bay, Everglades National Park, in June 2001 indicate that significant environmental changes occurred at the site over the last two centuries. The core was collected at a site of documented seagrass die-off in 1987-1988. The purpose of this study was to document the long-term sequences of events leading up to the die-off event. Analyses have been conducted to examine (1) faunal changes in the ostracodes and mollusks, (2) biochemistry of the ostracode shells, (3) floral changes in the pollen assemblages, and (4) geochemical and elemental changes in the sediment. The faunal assemblage analyses provide information on the salinity and benthic habitat at the site. The biochemical and geochemical data provide information about the water chemistry and sedimentation rates. The floral assemblage provides data about the nearby terrestrial environment and the first occurrence of pollen of the Australian pine, Casuarina equisetifolia , serves as a biostratigraphic marker for the beginning of the 20th century. These data provide clues to the cause and effect of the seagrass die-off and changes in salinity patterns and also illustrate decadal-scale patterns of change. The analyses of GLBW601 RL1 show two important results. First, prior to 1900, Rankin Basin tended to be oligohaline to mesohaline on the basis of faunal data showing the assemblage to be similar to that of the lowest portions of a core from Taylor Creek. Second, prior to the documented seagrass die-off, the faunal assemblages indicate an increase in the amplitude of salinity fluctuations; a significant increase occurs in the mollusks Brachidontes exustus and Anomalocardia auberiana , two species that tolerate fluctuations in salinity.

Florida↗

Kittlitz’s and Marbled Murrelets in Kenai Fjords National Park, south-central Alaska: At-sea distribution, abundance, and foraging habitat, 2006–08

Kittlitz’s murrelets ( Brachyramphus brevirostris ) and marbled murrelets ( B. marmoratus ) are small diving seabirds and are of management concern because of population declines in coastal Alaska. In 2006–08, we conducted a study in Kenai Fjords National Park, south-central Alaska, to estimate the recent population size of Brachyramphus murrelets, to evaluate productivity based on juvenile to adult ratios during the fledgling season, and to describe and compare their use of marine habitat. We also attempted a telemetry study to examine Kittlitz’s murrelet nesting habitat requirements and at-sea movements. We estimated that the Kittlitz’s murrelet population was 671 ± 144 birds, and the marbled murrelet population was 5,855 ± 1,163 birds. Kittlitz’s murrelets were limited to the heads of three fjords with tidewater glaciers, whereas marbled murrelets were more widely distributed. Population estimates for both species were lower in 2007 than in 2006 and 2008, possibly because of anomalous oceanographic conditions that may have delayed breeding phenology. During late season surveys, we observed few hatch-year marbled murrelets and only a single hatch-year Kittlitz’s murrelet over the course of the study. Using radio telemetry, we found a likely Kittlitz’s murrelet breeding site on a mountainside bordering one of the fjords. We never observed radio-tagged Kittlitz’s murrelets greater than 10 kilometer from their capture sites, suggesting that their foraging range during breeding is narrow. We observed differences in oceanography between fjords, reflecting differences in sill characteristics and orientation relative to oceanic influence. Acoustic biomass, a proxy for zooplankton and small schooling fish, generally decreased with distance from glaciers in Northwestern Lagoon, but was more variable in Aialik Bay where dense forage fish schools moved into glacial areas late in the summer. Pacific herring ( Clupea pallasii ), capelin ( Mallotus villosus ) and Pacific sand lance ( Ammodytes hexapterus ) were important forage species for murrelets in Kenai Fjords. Euphausiids also may have been an important forage resource for Kittlitz’s murrelets in turbid glacial outflows in shallow waters during daytime. Marbled murrelets generally were more tolerant to a wider range of foraging habitat conditions although they tended to avoid the ice-covered silty waters close to glaciers. In contrast, Kittlitz’s murrelets preferred areas where the influence of tidewater glaciers was the greatest and where their distribution was determined largely by prey availability. This work highlights an important link between interannual variability in murrelet counts at sea and mesoscale oceanographic conditions that influence marine productivity and prey distribution.

Open-File Report↗

Water-chemistry data for selected springs, geysers, and streams in Yellowstone National Park, Wyoming, 2006-2008

Water analyses are reported for 104 samples collected from numerous thermal and non-thermal features in Yellowstone National Park (YNP) during 2006-2008. Water samples were collected and analyzed for major and trace constituents from 10 areas of YNP including Apollinaris Spring and Nymphy Creek along the Norris-Mammoth corridor, Beryl Spring in Gibbon Canyon, Norris Geyser Basin, Lower Geyser Basin, Crater Hills, the Geyser Springs Group, Nez Perce Creek, Rabbit Creek, the Mud Volcano area, and Washburn Hot Springs. These water samples were collected and analyzed as part of research investigations in YNP on arsenic, antimony, iron, nitrogen, and sulfur redox species in hot springs and overflow drainages, and the occurrence and distribution of dissolved mercury. Most samples were analyzed for major cations and anions, trace metals, redox species of antimony, arsenic, iron, nitrogen, and sulfur, and isotopes of hydrogen and oxygen. Analyses were performed at the sampling site, in an on-site mobile laboratory vehicle, or later in a U.S. Geological Survey laboratory, depending on stability of the constituent and whether it could be preserved effectively. Water samples were filtered and preserved on-site. Water temperature, specific conductance, pH, emf (electromotive force or electrical potential), and dissolved hydrogen sulfide were measured on-site at the time of sampling. Dissolved hydrogen sulfide was measured a few to several hours after sample collection by ion-specific electrode on samples preserved on-site. Acidity was determined by titration, usually within a few days of sample collection. Alkalinity was determined by titration within 1 to 2 weeks of sample collection. Concentrations of thiosulfate and polythionate were determined as soon as possible (generally a few to several hours after sample collection) by ion chromatography in an on-site mobile laboratory vehicle. Total dissolved iron and ferrous iron concentrations often were measured on-site in the mobile laboratory vehicle. Concentrations of dissolved aluminum, arsenic, boron, barium, beryllium, calcium, cadmium, cobalt, chromium, copper, iron, potassium, lithium, magnesium, manganese, molybdenum, sodium, nickel, lead, selenium, silica, strontium, vanadium, and zinc were determined by inductively coupled plasma-optical emission spectrometry. Trace concentrations of dissolved antimony, cadmium, cobalt, chromium, copper, lead, and selenium were determined by Zeeman-corrected graphite-furnace atomic-absorption spectrometry. Dissolved concentrations of total arsenic, arsenite, total antimony, and antimonite were determined by hydride generation atomic-absorption spectrometry using a flow-injection analysis system. Dissolved concentrations of total mercury and methylmercury were determined by cold-vapor atomic fluorescence spectrometry. Concentrations of dissolved chloride, fluoride, nitrate, bromide, and sulfate were determined by ion chromatography. For many samples, concentrations of dissolved fluoride also were determined by ion-specific electrode. Concentrations of dissolved ferrous and total iron were determined by the FerroZine colorimetric method. Concentrations of dissolved ammonium were determined by ion chromatography, with reanalysis by colorimetry when separation of sodium and ammonia peaks was poor. Dissolved organic carbon concentrations were determined by the wet persulfate oxidation method. Hydrogen and oxygen isotope ratios were determined using the hydrogen and CO 2 equilibration techniques, respectively.

Wyoming↗

Probability and volume of potential postwildfire debris flows in the 2012 High Park Burn Area near Fort Collins, Colorado

This report presents a preliminary emergency assessment of the debris-flow hazards from drainage basins burned by the 2012 High Park fire near Fort Collins in Larimer County, Colorado. Empirical models derived from statistical evaluation of data collected from recently burned basins throughout the intermountain western United States were used to estimate the probability of debris-flow occurrence and volume of debris flows along the burned area drainage network and to estimate the same for 44 selected drainage basins along State Highway 14 and the perimeter of the burned area. Input data for the models included topographic parameters, soil characteristics, burn severity, and rainfall totals and intensities for a (1) 2-year-recurrence, 1-hour-duration rainfall (25 millimeters); (2) 10-year-recurrence, 1-hour-duration rainfall (43 millimeters); and (3) 25-year-recurrence, 1-hour-duration rainfall (51 millimeters). Estimated debris-flow probabilities along the drainage network and throughout the drainage basins of interest ranged from 1 to 84 percent in response to the 2-year-recurrence, 1-hour-duration rainfall; from 2 to 95 percent in response to the 10-year-recurrence, 1-hour-duration rainfall; and from 3 to 97 in response to the 25-year-recurrence, 1-hour-duration rainfall. Basins and drainage networks with the highest probabilities tended to be those on the eastern edge of the burn area where soils have relatively high clay contents and gradients are steep. Estimated debris-flow volumes range from a low of 1,600 cubic meters to a high of greater than 100,000 cubic meters. Estimated debris-flow volumes increase with basin size and distance along the drainage network, but some smaller drainages were also predicted to produce substantial volumes of material. The predicted probabilities and some of the volumes predicted for the modeled storms indicate a potential for substantial debris-flow impacts on structures, roads, bridges, and culverts located both within and immediately downstream from the burned area. Colorado State Highway 14 is also susceptible to impacts from debris flows.

Colorado↗

Nearshore morphology, benthic structure, hydrodynamics, and coastal groundwater discharge near Kahekili Beach Park, Maui, Hawaii

This report presents a brief summary of recent fieldwork conducted off Kahekili Beach Park, Maui, Hawaii, the site of the newly established U.S. Coral Reef Task Force priority study area at Kaanapali and the Hawaii Department of Land and Natural Resources, Division of Aquatic Resources, Kahekili Herbivore Fisheries Management Area (HFMA). The goals of this fieldwork are to provide new baseline information to help guide future studies and to provide first insights into rates and drivers of coastal groundwater discharge and associated constituent loadings into the priority study area's coastal waters. This study presents the first swath acoustic mapping information, in situ oceanographic instrument measurements, and coastal groundwater discharge estimates at this site based on the submarine groundwater discharge tracer radon-222 ( 222 Rn). Coastal groundwater discharge rates ranged from about 22 to 50 centimeters per day, depending on proximity of the sampling mooring to the primary discharge vent. The water chemistry of the discharging groundwater was at times dramatically different than ambient seawater. For example, at the primary vent site at Kahekili, the concentrations of total dissolved nitrogen (TDN), dissolved silicate (DSi), and total dissolved phosphorus (TDP) in the discharging groundwater were 43.75 micromolar (&mu;M), 583.49 &mu;M, and 12.04 &mu;M, respectively. These data extend our basic understanding of the morphology, benthic structure, and oceanographic setting of this vent site and provide a first estimate of the magnitude and physical forcings of submarine groundwater discharge and associated trace metals and nutrient loads here.

Hawai'i↗

Chronology from sediment cores collected in southwestern Everglades National Park, Florida

Age model data are presented for 10 cores from the southwestern coastal mangrove zone of Everglades National Park, Florida, collected in Common Era (CE) 2004 and 2005 and used for paleoecological analysis. Carbon-14 ( 14 C), lead-210 ( 210 Pb), cesium-137 ( 137 Cs), radium-226 ( 226 Ra), and pollen biostratigraphic information is included, and age models were generated for 6 of the 10 cores. Age reversals and sediment disturbance prevented construction of age models on the remaining four cores. Four cores present a continuous record of the last 50 to 100 years, making them useful for analyzing the impacts caused by changes in water management in south Florida. These cores are Harney River 2A and Harney River 1A, Shark River 2A, and Roberts River.

Florida↗