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1.
Am J Intellect Dev Disabil ; 127(4): 270-277, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-36122325

RESUMEN

The COVID-19 pandemic has been hard for everyone. For the estimated seven and a half million people in the United States who live with intellectual disability (Residential Information Systems Project, 2020), it has been very hard. Lives have been disrupted by lost jobs, lack of access to friends/family, and challenges finding enough staff to provide supports and needed healthcare. Studies have shown that people with IDD are at a much greater risk of getting COVID-19 and dying from it (Cuypers et al., 2020; Gleason et al., 2021; Kaye, 2021; Landes, Turk, & Ervin, 2020; Nygren & Lulinski, 2020). Without question, people with intellectual and developmental disabilities (IDD) struggled as the COVID-19 pandemic began and as it has continued. Too many were isolated from friends and family for far too long. Too many were lonely and bored. Too many have not received the support they have needed during the pandemic. Far too many were denied treatment and far too many have died. As a nation we must reflect on what has happened and listen to people with IDD and their families about their experiences. This commentary reflects on the implications of COVID-19 for research, policy, and practice through the lens of people with IDD.


Asunto(s)
COVID-19 , Discapacidad Intelectual , Niño , Discapacidades del Desarrollo/epidemiología , Humanos , Discapacidad Intelectual/epidemiología , Pandemias , Políticas , Estados Unidos/epidemiología
2.
J Thromb Haemost ; 19(1): 85-95, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33006808

RESUMEN

Essentials Liver diseases are associated with profound hemostatic changes proportional to severity of illness. Hemostatic changes in acute-on-chronic liver failure (ACLF) may in part reflect critical illness. Hemostatic changes in ACLF partly overlap with those in sepsis, with rebalanced hemostasis in both. Patients with sepsis had hyperfibrinogenemia, associated with a thrombogenic clot structure. ABSTRACT: Background Even the sickest patients with chronic liver disease (CLD), such as those with acute-on-chronic liver failure (ACLF) remain in hemostatic balance due to a concomitant decline in pro- and antihemostatic factors. Objectives We aimed to study whether the hemostatic status in ACLF is merely an exaggeration from the status in patients with compensated and acutely decompensated cirrhosis, or whether sepsis-associated hemostatic changes contribute. Methods We performed extensive hemostatic profiling in 31 adult patients with ACLF, 20 patients with sepsis without underlying CLD, and 40 healthy controls. Results We found similarly elevated plasma levels of the platelet adhesive protein von Willebrand factor (VWF) and decreased levels of the VWF-regulating protease ADAMTS13 in both groups compared to healthy controls. In vivo markers of activation of coagulation (thrombin-antithrombin III, D-dimer) were similarly elevated in both groups compared to controls, but ex vivo thrombin-generating capacity was similar between patients and controls, despite a much more profound international normalized ratio elevation in ACLF. Plasma fibrinogen levels were much higher in septics, which was accompanied by a decreased ex vivo clot permeability and an increase in ex vivo resistance to clot lysis. All hemostatic parameters were remarkably stable over the first 10 days after admission. Conclusions We have found hemostatic changes in ACLF to partially overlap with that of patients with sepsis, and evidence of preserved hemostatic capacity in both patient groups. The notable difference was a profound hyperfibrinogenemia, associated with a thrombogenic clot structure and a marked ex vivo resistance to fibrinolysis in patients with sepsis.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada , Hemostáticos , Insuficiencia Hepática Crónica Agudizada/diagnóstico , Adulto , Coagulación Sanguínea , Pruebas de Coagulación Sanguínea , Hemostasis , Humanos , Cirrosis Hepática
3.
Environ Toxicol Chem ; 39(12): 2437-2449, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32833245

RESUMEN

We examined the bioaccumulation of essential (Cu, Fe, Se, and Zn) and nonessential (As and Hg) trace elements in 2 aquatic invertebrate species (adult snails and mayfly nymphs) with different feeding habits at the site of a coal ash spill. Differences in food web pathway, exposure concentrations, and biological processing affected bioaccumulation patterns in these species. Mayflies had higher body burdens, but snails had higher retention of most elements studied. Environ Toxicol Chem 2020;39:2437-2449. © 2020 SETAC.


Asunto(s)
Bioacumulación , Ceniza del Carbón/análisis , Ephemeroptera/metabolismo , Caracoles/metabolismo , Oligoelementos/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , Arsénico/análisis , Arsénico/metabolismo , Monitoreo del Ambiente , Cadena Alimentaria , Metales Pesados/análisis , Metales Pesados/metabolismo , Ninfa/metabolismo , Ríos/química , Tennessee , Oligoelementos/análisis , Contaminantes Químicos del Agua/análisis
4.
Sci Total Environ ; 621: 1208-1223, 2018 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-29074249

RESUMEN

The reference condition paradigm has served as the standard for assessing the outcomes of restoration projects, particularly their success in meeting project objectives. One limitation of relying solely on the reference condition in designing and monitoring restoration projects is that reference conditions do not necessarily elucidate impairments to effective restoration, especially diagnosing the causal mechanisms behind unsuccessful outcomes. We provide a spatial framework to select both reference and non-reference streams to guide restoration planning and long-term monitoring through reliance on anthropogenically altered ecosystems to understand processes that govern ecosystem biophysical properties and ecosystem responses to restoration practices. We then applied the spatial framework to East Fork Poplar Creek (EFPC), Tennessee (USA), a system receiving 30years of remediation and pollution abatement actions from industrialization, pollution, and urbanization. Out of >13,000 stream reaches, we identified anywhere from 4 to 48 reaches, depending on the scenario, that could be used in restoration planning and monitoring for specific sites. Preliminary comparison of fish species composition at these sites compared to EFPC sites were used to identify potential mechanisms limiting the ecological recovery following remediation. We suggest that understanding the relative role of anthropogenic pressures in governing ecosystem responses is required to successful, process-driven restoration.

5.
Environ Toxicol Chem ; 35(5): 1159-71, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26387560

RESUMEN

A dike failure at the Tennessee Valley Authority Kingston Fossil Plant in East Tennessee, United States, in December 2008, released approximately 4.1 million m(3) of coal ash into the Emory River. From 2009 through 2012, samples of mayfly nymphs (Hexagenia bilineata) were collected each spring from sites in the Emory, Clinch, and Tennessee Rivers upstream and downstream of the spill. Samples were analyzed for 17 metals. Concentrations of metals were generally highest the first 2 miles downstream of the spill, and then decreased with increasing distance from the spill. Arsenic, B, Ba, Be, Mo, Sb, Se, Sr, and V appeared to have strong ash signatures, whereas Co, Cr, Cu, Ni, and Pb appeared to be associated with ash and other sources. However, the concentrations for most of these contaminants were modest and are unlikely to cause widespread negative ecological effects. Trends in Hg, Cd, and Zn suggested little (Hg) or no (Cd, Zn) association with ash. Temporal trends suggested that concentrations of ash-related contaminants began to subside after 2010, but because of the limited time period of that analysis (4 yr), further monitoring is needed to verify this trend. The present study provides important information on the magnitude of contaminant exposure to aquatic receptors from a major coal ash spill, as well as spatial and temporal trends for transport of the associated contaminants in a large open watershed.


Asunto(s)
Ceniza del Carbón/química , Fósiles , Insectos/química , Ninfa/química , Contaminantes Químicos del Agua/análisis , Animales , Metales/análisis , Ríos , Tennessee , Estados Unidos
6.
Chemosphere ; 138: 190-6, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26070084

RESUMEN

We assessed the impacts of an innovative Hg water treatment system on a small, industrially-contaminated stream in the southeastern United States. The treatment system, installed in 2007, removes Hg from wastewater using tin (Sn) (II) chloride followed by air stripping. Mercury concentrations in the receiving stream, Tims Branch, decreased from >100 to ∼10 ng/L in the four years following treatment, and Hg body burdens in redfin pickerel (Esox americanus) decreased by 70% at the most contaminated site. Tin concentrations in water and fish increased significantly in the tributary leading to Tims Branch, but concentrations remain below levels of concern for human health or ecological risks. While other studies have shown that Sn may be environmentally methylated and methyltin can transfer its methyl group to Hg, results from our field studies and sediment incubation experiments suggest that the added Sn to the Tims Branch watershed is not contributing to methylmercury (MeHg) production or bioaccumulation in this system. The stannous chloride treatment system installed at Tims Branch was effective at removing Hg inputs and reducing Hg bioaccumulation in the stream, but future studies are needed to assess longer term impacts of Sn on the environment.


Asunto(s)
Agua Dulce/química , Mercurio/análisis , Compuestos de Estaño/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Animales , Peces/metabolismo , Sedimentos Geológicos , Humanos , Mercurio/farmacocinética , Compuestos de Metilmercurio/análisis , Compuestos de Metilmercurio/farmacocinética , Estados Unidos , Contaminantes Químicos del Agua/farmacocinética
7.
PLoS Med ; 10(11): e1001548, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24265598

RESUMEN

Jeff Sloan and colleagues describe the development of the Patient-Reported Outcomes Quality of Life (PROQOL) instrument, which captures and stores patient-recorded outcomes in the medical record for patients with diabetes. Please see later in the article for the Editors' Summary.


Asunto(s)
Diabetes Mellitus/terapia , Atención al Paciente/normas , Mejoramiento de la Calidad , Calidad de Vida , Encuestas y Cuestionarios , Humanos
8.
Environ Manage ; 47(6): 1033-46, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21573910

RESUMEN

National Pollution Discharge Elimination Permit (NPDES)-driven effluent toxicity tests using Ceriodaphnia dubia and fathead minnows were conducted for more than 20 years to assess and monitor the effects of wastewaters at the United States (U.S.) Department of Energy Y-12 National Security Complex (Y-12 Complex) in Oak Ridge, Tennessee. Toxicity testing was also conducted on water samples from East Fork Poplar Creek (EFPC), the wastewater receiving stream, as part of a comprehensive biological monitoring and assessment program. In this paper, we evaluate the roles of this long-term toxicity assessment and monitoring program in the management and ecological recovery of EFPC. Effluent toxicity testing, associated toxicant evaluation studies, and ambient toxicity monitoring were instrumental in identifying toxicant sources at the Y-12 Complex, guiding modifications to wastewater treatment procedures, and assessing the success of various pollution-abatement actions. The elimination of untreated wastewater discharges, the dechlorination of remaining wastewater streams, and the implementation of flow management at the stream headwaters were the primary actions associated with significant reductions in the toxicity of stream water in the upper reaches of EFPC from the late 1980s through mid 1990s. Through time, as regulatory requirements changed and water quality improved, emphasis shifted from comprehensive toxicity assessments to more focused toxicity monitoring efforts. Ambient toxicity testing with C. dubia and fathead minnows was supplemented with less-standardized but more sensitive alternative laboratory toxicity tests and in situ bioassays. The Y-12 Complex biological monitoring experience demonstrates the value of toxicity studies to the management of a wastewater receiving stream.


Asunto(s)
Monitoreo del Ambiente/métodos , Ríos/química , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/estadística & datos numéricos , Animales , Cyprinidae , Daphnia , Tennessee , Pruebas de Toxicidad , Estados Unidos , United States Government Agencies , Contaminantes Químicos del Agua/toxicidad
9.
Environ Manage ; 47(6): 1010-20, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21384273

RESUMEN

In May 1985, a National Pollutant Discharge Elimination System permit was issued for the Department of Energy's Y-12 National Security Complex (Y-12 Complex) in Oak Ridge, Tennessee, USA, allowing discharge of effluents to East Fork Poplar Creek (EFPC). The effluents ranged from large volumes of chlorinated once-through cooling water and cooling tower blow-down to smaller discharges of treated and untreated process wastewaters, which contained a mixture of heavy metals, organics, and nutrients, especially nitrates. As a condition of the permit, a Biological Monitoring and Abatement Program (BMAP) was developed to meet two major objectives: demonstrate that the established effluent limitations were protecting the classified uses of EFPC, and document the ecological effects resulting from implementing a Water Pollution Control Program at the Y-12 Complex. The second objective is the primary focus of the other papers in this special series. This paper provides a history of pollution and the remedial actions that were implemented; describes the geographic setting of the study area; and characterizes the physicochemical attributes of the sampling sites, including changes in stream flow and temperature that occurred during implementation of the BMAP. Most of the actions taken under the Water Pollution Control Program were completed between 1986 and 1998, with as many as four years elapsing between some of the most significant actions. The Water Pollution Control Program included constructing nine new wastewater treatment facilities and implementation of several other pollution-reducing measures, such as a best management practices plan; area-source pollution control management; and various spill-prevention projects. Many of the major actions had readily discernable effects on the chemical and physical conditions of EFPC. As controls on effluents entering the stream were implemented, pollutant concentrations generally declined and, at least initially, the volume of water discharged from the Y-12 Complex declined. This reduction in discharge was of ecological concern and led to implementation of a flow management program for EFPC. Implementing flow management, in turn, led to substantial changes in chemical and physical conditions of the stream: stream discharge nearly doubled and stream temperatures decreased, becoming more similar to those in reference streams. While water quality clearly improved, meeting water quality standards alone does not guarantee protection of a waterbody's biological integrity. Results from studies on the ecological changes stemming from pollution-reduction actions, such as those presented in this series, also are needed to understand how best to restore or protect biological integrity and enhance ecological recovery in stream ecosystems. With a better knowledge of the ecological consequences of their decisions, environmental managers can better evaluate alternative actions and more accurately predict their effects.


Asunto(s)
Restauración y Remediación Ambiental/estadística & datos numéricos , Ríos/química , Contaminación Química del Agua/estadística & datos numéricos , Monitoreo del Ambiente , Concesión de Licencias , Estados Unidos , United States Government Agencies , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/normas , Contaminación Química del Agua/legislación & jurisprudencia
10.
Environ Manage ; 47(6): 1021-32, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21380789

RESUMEN

We review long-term changes that have occurred in factors affecting water quality in East Fork Poplar Creek (EFPC; in East Tennessee) over a nearly 25-year monitoring period. Historically, the stream has received wastewaters and pollutants from a major United States Department of Energy (DOE) facility on the headwaters of the stream. Early in the monitoring program, EFPC was perturbed chemically, especially within its headwaters; evidence of this perturbation extended downstream for many kilometers. The magnitude of this perturbation, and the concentrations of many biologically significant water-quality factors, has lessened substantially through time. The changes in water-quality factors resulted from a large number of operational changes and remedial actions implemented at the DOE facility. Chief among these were consolidation and elimination of many effluents, elimination of an unlined settling/flow equalization basin, reduction in amount of blow-down from cooling tower operations, dechlorination of effluents, and implementation of flow augmentation. Although many water-quality characteristics in upper EFPC have become more similar to those of reference streams, conditions remain far from pristine. Nutrient enrichment may be one of the more challenging problems remaining before further biological improvements occur.


Asunto(s)
Monitoreo del Ambiente , Ríos/química , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/estadística & datos numéricos , Organismos Acuáticos/efectos de los fármacos , Calcio/análisis , Conductividad Eléctrica , Nitratos/análisis , Sodio/análisis , Tennessee , Estados Unidos , United States Government Agencies , Contaminantes Químicos del Agua/toxicidad , Zinc/análisis
11.
Environ Manage ; 47(6): 1077-95, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21274531

RESUMEN

The benthic macroinvertebrate community of East Fork Poplar Creek (EFPC) in East Tennessee was monitored for 18 years to evaluate the effectiveness of a water pollution control program implemented at a major United States (U.S.) Department of Energy facility. Several actions were implemented to reduce and control releases of pollutants into the headwaters of the stream. Four of the most significant actions were implemented during different time periods, which allowed assessment of each action. Macroinvertebrate samples were collected annually in April from three locations in EFPC (EFK24, EFK23, and EFK14) and two nearby reference streams from 1986 through 2003. Significant improvements occurred in the macroinvertebrate community at the headwater sites (EFK24 and EFK23) after implementation of each action, while changes detected 9 km further downstream (EFK14) could not be clearly attributed to any of the actions. Because the stream was impacted at its origin, invertebrate recolonization was primarily limited to aerial immigration, thus, recovery has been slow. As recovery progressed, abundances of small pollution-tolerant taxa (e.g., Orthocladiinae chironomids) decreased and longer lived taxa colonized (e.g., hydropsychid caddisflies, riffle beetles, Baetis). While assessments lasting three to four years may be long enough to detect a response to new pollution controls at highly impacted locations, more time may be needed to understand the full effects. Studies on the effectiveness of pollution controls can be improved if impacted and reference sites are selected to maximize spatial and temporal trending, and if a multidisciplinary approach is used to broadly assess environmental responses (e.g., water quality trends, invertebrate and fish community assessments, toxicity testing, etc.).


Asunto(s)
Monitoreo del Ambiente/métodos , Restauración y Remediación Ambiental/métodos , Invertebrados/crecimiento & desarrollo , Contaminación Química del Agua/estadística & datos numéricos , Animales , Biodiversidad , Invertebrados/clasificación , Dinámica Poblacional , Tennessee , Estados Unidos , United States Government Agencies
12.
Ecology ; 91(2): 518-27, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20392016

RESUMEN

The light : nutrient hypothesis posits that herbivore growth is increasingly constrained by low food quality as the ratio of light to nutrients increases in aquatic ecosystems. We tested predictions of this hypothesis by examining the effects of large seasonal cycles in light and nutrients on the mineral content of periphyton and the growth rate of a dominant herbivore (the snail Elimia clavaeformis) in two oligotrophic streams. Streambed irradiances in White Oak Creek and Walker Branch (eastern Tennessee, USA) varied dramatically on a seasonal basis due to leaf phenology in the surrounding deciduous forests and seasonal changes in sun angle. Concentrations of dissolved nutrients varied inversely with light, causing light : nitrate and light : phosphate to range almost 100-fold over the course of any individual year. Periphyton nitrogen and phosphorus concentrations were much lower than the concentrations of these elements in snails, and they bottomed out in early spring when streambed irradiances were highest. Snail growth, however, peaked in early spring when light:nutrient ratios were highest and periphyton nutrient concentrations were lowest, Growth was linearly related to primary production (accounting for up to 85% of growth variance in individual years), which in turn was driven by seasonal variation in light. Conceptual models of herbivore growth indicate that growth should initially increase as increasing light levels stimulate primary production, but then level off, and then decrease as the negative effects of decreasing algal nutrient content override the positive effects of increased food production. Our results showed no evidence of an inflection point where increasing ratios of light to nutrients negatively affected growth. Snail growth in these intensively grazed streams is probably unaffected by periphyton nutrient content because exploitative competition for food reduces growth rates to levels where the demand for nitrogen and phosphorus is small enough to be satisfied by even low levels of these nutrients in periphyton. Competition for limited food resources in habitats where herbivore densities are uncontrolled by predation or other mortality factors should strongly influence the potential for herbivores to be limited by mineral deficits in their food.


Asunto(s)
Conducta Alimentaria/fisiología , Luz , Ríos , Caracoles/crecimiento & desarrollo , Caracoles/fisiología , Animales , Ecosistema , Factores de Tiempo
13.
Environ Manage ; 45(3): 563-76, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20108138

RESUMEN

The effects of pollutants on primary producers ramify through ecosystems because primary producers provide food and structure for higher trophic levels and they mediate the biogeochemical cycling of nutrients and contaminants. Periphyton (attached algae) were studied as part of a long-term biological monitoring program designed to guide remediation efforts by the Department of Energy's Y-12 National Security Complex on East Fork Poplar Creek (EFPC) in Oak Ridge, Tennessee. High concentrations of nutrients entering EFPC were responsible for elevated periphyton production and placed the stream in a state of eutrophy. High rates of primary production at upstream locations in EFPC were associated with alterations in both invertebrate and fish communities. Grazers represented >50% of the biomass of invertebrates and fish near the Y-12 Complex but <10% at downstream and reference sites. An index of epilithic periphyton production accounted for 95% of the site-to-site variation in biomass of grazing fish. Analyses of heavy metals in EFPC periphyton showed that concentrations of zinc, cadmium, copper and nickel in periphyton decreased exponentially with distance downstream from Y-12. Zinc uptake by periphyton was estimated to reduce the concentration of this metal in stream water approximately 60% over a 5-km reach of EFPC. Management options for mitigating eutrophy in EFPC include additional reductions in nutrient inputs and/or allowing streamside trees to grow and shade the stream. However, reducing periphyton growth may lead to greater downstream transport of contaminants while simultaneously causing higher concentrations of mercury and PCBs in fish at upstream sites.


Asunto(s)
Conservación de los Recursos Naturales/economía , Ecosistema , Eucariontes/metabolismo , Ríos , Contaminación Química del Agua/prevención & control , Animales , Biomasa , Conservación de los Recursos Naturales/métodos , Monitoreo del Ambiente , Eutrofización , Peces , Invertebrados , Metales/metabolismo , Metales/toxicidad , Nitrógeno/metabolismo , Nitrógeno/toxicidad , Fotosíntesis , Tennessee , Factores de Tiempo , Contaminantes Químicos del Agua/metabolismo
14.
J Environ Manage ; 88(4): 1452-70, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18022757

RESUMEN

Habitat valuation methods were implemented to support remedial decisions for aquatic and terrestrial contaminated sites at the East Tennessee Technology Park (ETTP) on the US Department of Energy (DOE) Oak Ridge Reservation in Oak Ridge, TN, USA. The habitat valuation was undertaken for six contaminated sites: Contractor's Spoil Area, K-901-N Disposal Area, K-770 Scrapyard, K-1007-P1 pond, K-901 pond, and the Mitchell Branch stream. Four of these sites are within the industrial use area of ETTP and two are in the Black Oak Ridge Conservation Easement. These sites represent terrestrial and aquatic habitat for vertebrates, terrestrial habitat for plants, and aquatic habitat for benthic invertebrates. Current and potential future, no-action (no remediation) scenarios were evaluated primarily using existing information. Valuation metrics and scoring criteria were developed in a companion paper, this volume. The habitat valuation consists of extensive narratives, as well as scores for aspects of site use value, site rarity, and use value added from spatial context. Metrics for habitat value were expressed with respect to different spatial scales, depending on data availability. There was significant variation in habitat value among the six sites, among measures for different taxa at a single site, between measures of use and rarity at a single site, and among measures for particular taxa at a single site with respect to different spatial scales. Most sites had aspects of low, medium, and high habitat value. Few high scores for current use value were given. These include: wetland plant communities at all aquatic sites, Lepomid sunfish and waterbirds at 1007-P1 pond, and Lepomid sunfish and amphibians at K-901 pond. Aquatic sites create a high-value ecological corridor for waterbirds, and the Contractor's Spoil Area and possibly the K-901-N Disposal Site have areas that are part of a strong terrestrial ecological corridor. The only example of recent observations of rare species at these sites is the gray bat observed at the K-1007-P1 pond. Some aspects of habitat value are expected to improve under no-action scenarios at a few of the sites. Methods are applicable to other contaminated sites where sufficient ecological data are available for the site and region.


Asunto(s)
Ecosistema , Contaminantes Ambientales , Restauración y Remediación Ambiental/métodos , Estados Unidos
15.
J Environ Manage ; 88(4): 1436-51, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17897773

RESUMEN

Habitat valuation methods are most often developed and used to prioritize candidate lands for conservation. In this study the intent of habitat valuation was to inform the decision-making process for remediation of chemical contaminants on specific lands or surface water bodies. Methods were developed to summarize dimensions of habitat value for six representative aquatic and terrestrial contaminated sites at the East Tennessee Technology Park (ETTP) on the US Department of Energy Oak Ridge Reservation in Oak Ridge, TN, USA. Several general valuation metrics were developed for three broad categories: site use by groups of organisms, site rarity, and use value added from spatial context. Examples of use value metrics are taxa richness, a direct measure of number of species that inhabit an area, complexity of habitat structure, an indirect measure of potential number of species that may use the area, and land use designation, a measure of the length of time that the area will be available for use. Measures of rarity included presence of rare species or communities. Examples of metrics for habitat use value added from spatial context included similarity or complementarity of neighboring habitat patches and presence of habitat corridors. More specific metrics were developed for groups of organisms in contaminated streams, ponds, and terrestrial ecosystems. For each of these metrics, cutoff values for high, medium, and low habitat value were suggested, based on available information on distributions of organisms and landscape features, as well as habitat use information. A companion paper describes the implementation of these habitat valuation metrics and scoring criteria in the remedial investigation for ETTP.


Asunto(s)
Ecosistema , Contaminantes Ambientales , Restauración y Remediación Ambiental/métodos
16.
Environ Manage ; 32(1): 77-92, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-14703914

RESUMEN

Recovery of the benthic macroinvertebrate community in a small east Tennessee stream impacted by fly ash discharges from a power plant was investigated over a period of 6.5 years. The rate of recovery was greatest in the first 2 years after an initial 75% reduction in coal use led to a similar reduction in ash discharges and associated contaminants; further recovery followed after all fly ash discharges ceased. Recovery of the stream progressed through two phases. In the first phase, which lasted for approximately the first 2 years, most density and richness metrics increased considerably. In the second phase of recovery, the increases in metric values were followed by declines before fluctuating in and out of the lower reference ranges for the metrics. Detrended correspondence analyses and indicator species analyses showed that changes in species composition and community structure were ongoing throughout the second phase. Thus, the first phase was characterized by species additions, while the second phase involved species replacements and shifts in community dominants. Further recovery of the macroinvertebrate community will probably depend on additional flushing of fly ash deposits from the streambed and flood plain, because their continued presence reduces habitat quality in the stream and serves as a potential source of contaminants. Further recovery also may be limited by the availability of vagile species in nearby watersheds.


Asunto(s)
Invertebrados , Eliminación de Residuos , Contaminación del Agua/prevención & control , Animales , Incineración , Dinámica Poblacional , Ríos , Movimientos del Agua
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