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1.
Br J Haematol ; 204(1): 74-85, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37964471

RESUMEN

No one doubts the significant variation in the practice of transfusion medicine. Common examples are the variability in transfusion thresholds and the use of tranexamic acid for surgery with likely high blood loss despite evidence-based standards. There is a long history of applying different strategies to address this variation, including education, clinical guidelines, audit and feedback, but the effectiveness and cost-effectiveness of these initiatives remains unclear. Advances in computerised decision support systems and the application of novel electronic capabilities offer alternative approaches to improving transfusion practice. In England, the National Institute for Health and Care Research funded a Blood and Transplant Research Unit (BTRU) programme focussing on 'A data-enabled programme of research to improve transfusion practices'. The overarching aim of the BTRU is to accelerate the development of data-driven methods to optimise the use of blood and transfusion alternatives, and to integrate them within routine practice to improve patient outcomes. One particular area of focus is implementation science to address variation in practice.


Asunto(s)
Transfusión Sanguínea , Humanos , Inglaterra
2.
J Environ Qual ; 45(4): 1329-43, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27380082

RESUMEN

Lowland waters in Northern Ireland experience elevated agricultural phosphorus (P) inputs, and in response a variety of control measures targeting farm nutrient management have been implemented. Their efficacy in lowering nitrogen (N) and P exports and improving water quality is examined in 40 headwater streams from 1990 to 2009, and to 2014 for 24 of these. Over this period manure production in the study catchments declined by 7%, but regional chemical fertilizer inputs declined by 37% for N and 79% for P, and the regional nutrient surplus was lowered by 18% for N and 49% for P. Diminished pollution by organic wastes meant that 85% of streams exhibited chemistry suitable for salmonids in 2009 compared to 40% in 1990. Flow-weighted mean concentrations (FWMCs) of nutrients declined between 1990 and 2009, and their correlations with catchment stocking rates became stronger over time. For catchments with manure inputs <16.6 kg P ha, total P and nitrate FWMCs declined from 123 ± 19 µg P L and 1.92 ± 0.5 mg N L in 1990 at rates of 2.2 ± 0.5 and 30 ± 10 µg L yr, respectively. For catchments with higher manure inputs the respective rates of decline were greater at 5.8 ± 1.0 µg P L yr and 160 ± 20 µg N L yr from 1990 concentrations of 270 ± 25 µg P L and 5.99 ± 0.4 mg N L. Although now lower, P concentrations in the more highly stocked catchments still exceed regional nutrient standards so that the identification of further factors impinging on nutrient losses is critical if such standards are to be achieved.


Asunto(s)
Agricultura , Nitrógeno/análisis , Fósforo/análisis , Contaminantes del Agua/análisis , Monitoreo del Ambiente , Ríos
3.
Poult Sci ; 93(11): 2718-23, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25260527

RESUMEN

Microbial phytases increase the bioavailability of phytate P in poultry diets, and a survey was undertaken to determine if their use had lowered the P composition of broiler litter in Northern Ireland compared with standard values of litter composition listed in the current United Kingdom fertilizer recommendations. Litter samples were collected from a total of 20 units across Northern Ireland in 2010 and analyzed for DM, N, phosphate (P2O5), potash (K2O), magnesium oxide (MgO), water-soluble P (WSP), ammonium N (NH4N), and uric acid N. Dry matter of litter was positively correlated (P < 0.001) with N (r(2) = 0.65), P2O5 (r(2) = 0.63), K2O (r(2) = 0.56), and MgO (r(2) = 0.58). Negative correlations were observed between litter DM and WSP (r(2) = 0.45, P < 0.001) and NH4N (r(2) = 0.22, P = 0.038) contents. A standardized litter composition with a 60% DM gave a phosphate content of 13.7 kg/t that was 45% lower than the fertilizer book value (RB209), but there were only slight differences (<3%) between book values and DM standardized values for N and potash contents. Uric acid and NH4 contents were similar to published values. Mean N:P ratio (by weight) of litter increased from 3.7 in 2004 to 5.0 in 2010, lowering the risk of oversupply of P if land applications are targeted to meet N supply. Using the standard RB209 values to plan land applications of broiler litter to meet crop P demands risks undersupplying P, and there is a need for the regulatory values to be modified in light of the changing composition of broiler litter.


Asunto(s)
6-Fitasa/metabolismo , Pollos/metabolismo , Estiércol/análisis , Fósforo/análisis , Alimentación Animal/análisis , Animales , Dieta/veterinaria , Irlanda del Norte
4.
J Fish Biol ; 80(5): 1508-45, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22497395

RESUMEN

Stable-isotope ratios of nitrogen (δ¹5N) and lipid-normalized carbon (δ¹³C') were used to examine geographic and ontogenetic variability in the trophic ecology of a high latitude benthopelagic elasmobranch, the Pacific sleeper shark Somniosus pacificus. Mean muscle tissue δ¹³C' values of S. pacificus differed significantly among geographic regions of the eastern North Pacific Ocean. Linear models identified significant ontogenetic and geographic variability in muscle tissue δ¹5N values of S. pacificus. The trophic position of S. pacificus in the eastern North Pacific Ocean estimated here from previously published stomach-content data (4·3) was within the range of S. pacificus trophic position predicted from a linear model of S. pacificus muscle tissue δ¹5N (3·3-5·7) for fish of the same mean total length (L(T) ; 201·5 cm), but uncertainty in predicted trophic position was very high (95% prediction intervals ranged from 2·9 to 6·4). The relative trophic position of S. pacificus determined here from a literature review of δ¹5N by taxa in the eastern North Pacific Ocean was also lower than would be expected based on stomach-content data alone when compared to fishes, squid and filter feeding whales. Stable-isotope analysis revealed wider variability in the feeding ecology of S. pacificus in the eastern North Pacific Ocean than shown by diet data alone, and expanded previous conclusions drawn from analyses of stomach-content data to regional and temporal scales meaningful for fisheries management.


Asunto(s)
Dieta , Cadena Alimentaria , Tiburones/fisiología , Animales , Isótopos de Carbono/análisis , Contenido Digestivo , Modelos Lineales , Músculos/química , Isótopos de Nitrógeno/análisis , Océano Pacífico
5.
J Environ Manage ; 93(1): 225-34, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22054589

RESUMEN

The Water Framework Directive (WFD) has initiated a shift towards a targeted approach to implementation through its focus on river basin districts as management units and the natural ecological characteristics of waterbodies. Due to its role in eutrophication, phosphorus (P) has received considerable attention, resulting in a significant body of research, which now forms the evidence base for the programme of measures (POMs) adopted in WFD River Basin Management Plans (RBMP). Targeting POMs at critical sources areas (CSAs) of P could significantly improve environmental efficiency and cost effectiveness of proposed mitigation strategies. This paper summarises the progress made towards targeting mitigation measures at CSAs in Irish catchments. A review of current research highlights that knowledge related to P export at field scale is relatively comprehensive however; the availability of site-specific data and tools limits widespread identification of CSA at this scale. Increasing complexity of hydrological processes at larger scales limits accurate identification of CSA at catchment scale. Implementation of a tiered approach, using catchment scale tools in conjunction with field-by-field surveys could decrease uncertainty and provide a more practical and cost effective method of delineating CSA in a range of catchments. Despite scientific and practical uncertainties, development of a tiered CSA-based approach to assist in the development of supplementary measures would provide a means of developing catchment-specific and cost-effective programmes of measures for diffuse P. The paper presents a conceptual framework for such an approach, which would have particular relevance for the development of supplementary measures in High Status Waterbodies (HSW). The cost and resources necessary for implementation are justified based on HSWs' value as undisturbed reference condition ecosystems.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Monitoreo del Ambiente/métodos , Política Ambiental , Fósforo , Contaminantes Químicos del Agua , Contaminación Química del Agua/prevención & control , Calidad del Agua , Agricultura/métodos , Conservación de los Recursos Naturales/economía , Conservación de los Recursos Naturales/legislación & jurisprudencia , Análisis Costo-Beneficio , Monitoreo del Ambiente/economía , Monitoreo del Ambiente/legislación & jurisprudencia , Unión Europea , Eutrofización , Agua Dulce , Irlanda , Fósforo/análisis , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/análisis
6.
Implement Sci Commun ; 3(1): 32, 2022 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-35313992

RESUMEN

BACKGROUND: Audit and feedback is widely used in healthcare improvement, with evidence of modest yet potentially important effects upon professional practice. There are approximately 60 national clinical audit programmes in the UK. These programmes often develop and adapt new ways of delivering feedback to optimise impacts on clinical practice. Two such programmes, the National Diabetes Audit (NDA) and the Trauma Audit Research Network (TARN), recently introduced changes to their delivery of feedback. We assessed the extent to which the design of these audit programmes and their recent changes were consistent with best practice according to the Clinical Performance Feedback Intervention Theory (CP-FIT). This comprehensive framework specifies how variables related to the feedback itself, the recipient, and the context operate via explanatory mechanisms to influence feedback success. METHODS: We interviewed 19 individuals with interests in audit and feedback, including researchers, audit managers, healthcare staff, and patient and public representatives. This range of expert perspectives enabled a detailed exploration of feedback from the audit programmes. We structured interviews around the CP-FIT feedback cycle and its component processes (e.g. Data collection and analysis, Interaction). Our rapid analytic approach explored the extent to which both audits applied features consistent with CP-FIT. RESULTS: Changes introduced by the audit programmes were consistent with CP-FIT. Specifically, the NDA's increased frequency of feedback augmented existing strengths, such as automated processes (CP-FIT component: Data collection and analysis) and being a credible source of feedback (Acceptance). TARN's new analytic tool allowed greater interactivity, enabling recipients to interrogate their data (Verification; Acceptance). We also identified scope for improvement in feedback cycles, such as targeting of feedback recipients (Interaction) and feedback complexity (Perception) for the NDA and specifying recommendations (Intention) and demonstrating impact (Clinical performance improvement) for TARN. CONCLUSIONS: The changes made by the two audit programmes appear consistent with suggested best practice, making clinical improvement more likely. However, observed weaknesses in the feedback cycle may limit the benefits of these changes. Applying CP-FIT via a rapid analysis approach helps identify strengths and remediable weaknesses in the design of audit programmes that can be shared with them in a timely manner.

7.
Water Sci Technol ; 64(1): 22-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22053453

RESUMEN

Constructed wetlands (CWs) have been used to treat agricultural effluents with varying success especially with respect to their operational efficiency in winter and ability to retain phosphorus. Dirty water (DW) from dairy farms is a mixture of manure contaminated runoff and milk parlour washings with a highly polluting biochemical oxygen demand (BOD) < or =3000 mg/L. The initial performance a CW of a 1.2 ha horizontal flow CW consisting of five ponds in series designed to treat DW from a dairy unit was assessed over four years. Ponds were earth-lined and shallow (0.3 m) with a water residence time of 100 days and planted with five species of emergent macrophytes. In comparison to CW inflow, annual reductions were as follows: BOD 99%, P 95% and N 92.8%. Coliforms were reduced by a 10(-5) factor to natural levels. From May to October there was little CW discharge due to evaporative losses. Final effluent quality was poorest in February but remained within a regulatory effluent standard for BOD of 40 mg/L. If the CW had only four ponds (25% less surface area) effluent would have failed the BOD standard in three years.


Asunto(s)
Industria Lechera , Eliminación de Residuos Líquidos/métodos , Contaminación Química del Agua/análisis , Análisis de la Demanda Biológica de Oxígeno/normas , Enterobacteriaceae/aislamiento & purificación , Irlanda del Norte , Fósforo/análisis , Estanques/microbiología , Compuestos de Amonio Cuaternario/análisis , Estaciones del Año , Humedales
8.
J Environ Qual ; 39(6): 2138-46, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21284312

RESUMEN

The increasing use of concentrate feedstuffs within Northern Ireland dairy systems has resulted in significant farm gate phosphorus (P) surpluses, and these have contributed to increased soil P levels and risk of P loss to overland flow. However, the P content of feed concentrates can be lowered without compromising animal performance. This study focuses on P losses from grassland and evaluates how adjusting the P content of manure impacts on the P composition and concentration in overland flow. Dairy cows were offered diets containing 5.3 to 3.0 g P kg(-1) dry matter (DM) and produced manures with a range of P contents. Manure was applied at a rate of 50 m3 ha(-1) to 0.5-m2 grassland plots, and simulated rainfall (40 mm h(-1)) was applied repeatedly 2, 9, 28, and 49 d after during the summer, winter, and spring. Decreasing the P content in the diet, from the highest to the lowest P treatment (43%), produced a proportionately greater reduction in manure TP content (63%), but reductions were not exclusively in the water-soluble fraction. Following surface applications of manure, P concentrations in overland flow increased in all seasons (P < or = 0.001), while the greatest impact of varying the manure P content was most evident during the first simulated overland flow event. When diet P content was reduced from 5.4 to 3.0 g P kg(-1) DM, a statistically significant reduction in runoff P concentration was observed in all seasons. Elevated P concentrations in overland flow were observed for 28 d in spring and 9 d in summer and winter. The large drop in P concentrations between simulated rainfall events on Day 2 and Day 9 suggests that increasing the time interval between manure application and the generation of overland flow has a greater impact on P losses than does varying the dietary P content.


Asunto(s)
Alimentación Animal/análisis , Bovinos , Industria Lechera , Dieta/veterinaria , Estiércol , Fósforo/química , Animales , Femenino , Lluvia , Estaciones del Año , Factores de Tiempo , Movimientos del Agua , Contaminantes Químicos del Agua/química
9.
J Radiol Prot ; 29(4): 483-90, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19923639

RESUMEN

The use of mobile head computed tomography (CT) equipment in intensive care is of benefit to unstable patients with brain injury. However, ionising radiation in a ward environment presents difficulties due to the necessity to restrict the exposure to staff and members of the public according to regulation 8(1-2) of the Ionising Radiation Regulations 1999. The methodology for enabling the use of a mobile head CT unit in an open ward area is discussed and a practical solution given. This required the reduction in scatter doses through the installation of extra internal and external shielding, and a further reduction in annual scatter dose by restricting the use of the equipment based on a simulation of the annual ward workload.


Asunto(s)
Cuidados Críticos/legislación & jurisprudencia , Cuidados Críticos/normas , Adhesión a Directriz/legislación & jurisprudencia , Guías de Práctica Clínica como Asunto , Protección Radiológica/legislación & jurisprudencia , Tomografía Computarizada por Rayos X/instrumentación , Tomografía Computarizada por Rayos X/normas , Adhesión a Directriz/normas , Protección Radiológica/normas , Reino Unido
10.
BMC Health Serv Res ; 5: 50, 2005 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-16011811

RESUMEN

BACKGROUND: Improving the quality of health care requires a range of evidence-based activities. Audit and feedback is commonly used as a quality improvement tool in the UK National Health Service [NHS]. We set out to assess whether current guidance and systematic review evidence can sufficiently inform practical decisions about how to use audit and feedback to improve quality of care. METHODS: We selected an important chronic disease encountered in primary care: diabetes mellitus. We identified recommendations from National Institute for Clinical Excellence (NICE) guidance on conducting audit and generated questions which would be relevant to any attempt to operationalise audit and feedback in a healthcare service setting. We explored the extent to which a systematic review of audit and feedback could provide practical guidance about whether audit and feedback should be used to improve quality of diabetes care and, if so, how audit and feedback could be optimised. RESULTS: National guidance suggests the importance of securing the right organisational conditions and processes. Review evidence suggests that audit and feedback can be effective in changing healthcare professional practice. However, the available evidence says relatively little about the detail of how to use audit and feedback most efficiently. CONCLUSION: Audit and feedback will continue to be an unreliable approach to quality improvement until we learn how and when it works best. Conceptualising audit and feedback within a theoretical framework offers a way forward.


Asunto(s)
Diabetes Mellitus , Medicina Basada en la Evidencia , Retroalimentación , Auditoría Médica , Guías de Práctica Clínica como Asunto , Atención Primaria de Salud , Garantía de la Calidad de Atención de Salud , Humanos , Diabetes Mellitus/prevención & control , Diabetes Mellitus/terapia , Educación del Paciente como Asunto , Atención Primaria de Salud/normas , Garantía de la Calidad de Atención de Salud/métodos , Medicina Estatal/normas , Reino Unido , Revisiones Sistemáticas como Asunto
11.
Qual Saf Health Care ; 12(3): 205-9, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12792011

RESUMEN

Clinical guidelines often make recommendations on the use of diagnostic tests. Compared with sensitivity and specificity, the use of pre- and post-test probabilities allows a more explicit and rational selection and interpretation of diagnostic tests. Ideally, clinical guidelines relating to diagnosis should routinely incorporate this information to enhance individualised decision making. We report our experience of incorporating pre- and post-test probabilities into a guideline on the investigation of women with postmenopausal bleeding developed by the Scottish Intercollegiate Guidelines Network. Issues relating to their application are highlighted, including the limitations of available evidence on diagnostic tests and prevalence of disease, acceptability to guideline users, and the uncertain impact on actual clinical decision making. Despite these potential difficulties, the incorporation of data on pre- and post-test probabilities into the development and presentation of guideline recommendations may offer an important opportunity to make clinical decision making more transparent for both clinicians and patients.


Asunto(s)
Técnicas de Diagnóstico Obstétrico y Ginecológico/estadística & datos numéricos , Guías de Práctica Clínica como Asunto , Hemorragia Uterina/diagnóstico , Toma de Decisiones , Femenino , Humanos , Persona de Mediana Edad , Posmenopausia/fisiología , Pautas de la Práctica en Medicina , Prevalencia , Probabilidad , Escocia , Sensibilidad y Especificidad , Hemorragia Uterina/epidemiología
12.
J Epidemiol Community Health ; 52(5): 305-9, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9764281

RESUMEN

STUDY OBJECTIVE: To assess the role of testing for Helicobacter pylori in the management of dyspeptic patients in primary care. DESIGN: Selective review of literature frequently quoted to support use of H pylori testing. MAIN RESULTS: Testing for H pylori and referral of only positive cases for endoscopy aims to reduce the number of "unnecessary" endoscopies. Patients with negative results may receive short-term reassurance and subsequently place fewer demands on health services. However, studies to date have only assessed this practice in secondary care settings. Given the relatively high prevalence of both dyspepsia and H pylori infection, the transfer of this practice to primary care may lead to a paradoxical increase in endoscopy referrals. Identification of H pylori and prescribing of eradication treatment also aims to reduce endoscopy referrals. No primary care trials have yet assessed this approach. Given that fewer than one in four of dyspeptic patients have peptic ulceration, a high proportion may fail to respond to eradication treatment and subsequently require referral for endoscopy. The longer term clinical and psychosocial sequelae of treating or labelling patients with an infection associated with gastric cancer remain unknown. CONCLUSIONS: Given uncertainty concerning the possible adverse effects of H pylori testing in primary care, we suggest a moratorium on its use in this setting until results from relevant clinical trials become available.


Asunto(s)
Dispepsia/microbiología , Infecciones por Helicobacter/diagnóstico , Helicobacter pylori/aislamiento & purificación , Anciano , Pruebas Respiratorias , Dispepsia/terapia , Medicina Familiar y Comunitaria , Femenino , Infecciones por Helicobacter/terapia , Helicobacter pylori/inmunología , Humanos , Masculino , Persona de Mediana Edad , Selección de Paciente , Úlcera Péptica/microbiología , Úlcera Péptica/terapia , Derivación y Consulta , Sensibilidad y Especificidad , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/terapia
13.
Life Sci ; 49(4): 299-308, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-2072818

RESUMEN

This study was designed to assess the effects of cocaine on coronary arterial smooth muscle and to determine whether previously reported cocaine-induced coronary vasospasm is mediated by substances released from the endothelium or by increased adrenergic receptor stimulation. Concentration-response relationships for cocaine (0.1-300 microM) and norepinephrine (0.1-300 microM) were studied in vitro using 2 mm segments of bovine proximal left anterior descending coronary artery. Each segmental ring was mounted in a 70 ml tissue bath for the measurement of isometric tension. Cocaine (3-300 microM) caused significant, concentration-dependent, increases in developed tension (p less than 0.05). Removal of the endothelium or pretreatment with prazosin (0.1 microM) or propranolol (1 microM) did not significantly alter this action of cocaine. In contrast to cocaine, norepinephrine (10-300 microM) caused significant decreases in developed tension (p less than 0.01). These findings suggest that cocaine-induced contraction of bovine coronary vascular smooth muscle is not mediated by endothelium derived contracting substances or norepinephrine.


Asunto(s)
Cocaína/farmacología , Vasos Coronarios/efectos de los fármacos , Contracción Muscular/efectos de los fármacos , Músculo Liso Vascular/efectos de los fármacos , Norepinefrina/farmacología , Animales , Arterias/efectos de los fármacos , Arterias/fisiología , Bovinos , Vasos Coronarios/fisiología , Endotelio Vascular/fisiología , Técnicas In Vitro , Músculo Liso Vascular/fisiología , Prazosina/farmacología , Propranolol/farmacología
14.
Br J Gen Pract ; 47(418): 311-2, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9219410

RESUMEN

The availability of non-invasive tests for the detection of Helicobactor pylori infection in primary care is increasing. However, the World Health Organization (WHO) has recently labelled H. pylori as a Class 1 carcinogen. We describe how frequently general practitioners (GPs) inform patients of this association prior to offering an H. pylori serology test, and discuss the possible consequences of withholding this information.


Asunto(s)
Infecciones por Helicobacter/complicaciones , Helicobacter pylori , Educación del Paciente como Asunto , Neoplasias Gástricas/microbiología , Medicina Familiar y Comunitaria/métodos , Infecciones por Helicobacter/diagnóstico , Humanos
15.
Br J Gen Pract ; 49(439): 127-8, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10326267

RESUMEN

This pilot study suggests that changes in prescribing policy for nicotine replacement patches should be made only when evidence of cost-effectiveness can be adduced from a randomized controlled trial.


Asunto(s)
Nicotina/economía , Cese del Hábito de Fumar/economía , Administración Cutánea , Adulto , Análisis Costo-Beneficio , Costos de los Medicamentos , Medicina Familiar y Comunitaria , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nicotina/administración & dosificación , Proyectos Piloto
16.
Water Res ; 35(12): 3004-12, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11471701

RESUMEN

Water quality was measured in 42 streams in the Colebrooke and Upper Bann catchments in Northern Ireland over the period 1990-1998. Despite ongoing pollution control measures, biological water quality, as determined by the invertebrate average score per taxon (ASPT) index, did not improve and there was no appreciable decline in recorded farm pollution incidents. However, the lack of decline in pollution incidents could reflect changes in detection policy, as a greater proportion of incidents were recorded from less polluting discharges such as farm-yard runoff. In contrast, there was an improvement during 1997 and 1998 in annual chemical water quality classification based on exceedence values (90th percentiles) for dissolved oxygen, ammonium and BOD concentrations. In 1998, 11.9% of streams were severely polluted compared to 26.2% in 1990, while the proportion classed as of salmonid water quality, increased from 40.5% in 1990 to 59.6% in 1998. Although water quality in 1996 did not improve relative to 1990 values, there was a notable increasing trend from 1990 in the numbers of samples taken during the summer which had good water quality with low ammonium (<0.6mgN l(-1)) and high dissolved oxygen (> 70% sat). The trend for samples with low BOD (<4 mgl(-1)) was more erratic, but an improvement was apparent from 1994. These improvements in chemical water quality suggest that point-source farm pollution declined after 1990. The fact that this was not reflected in stream biology may reflect the limited time scale for biological recovery. An important factor preventing biological recovery may be the high pollution capacity of manures and silage effluent, so that even reduced numbers of farm pollution incidents can severely perturb stream ecosystems. The intractable nature of farm pollution suggests that there is a need to consider an interactive approach to problem resolution involving both farmers and regulators.


Asunto(s)
Agroquímicos , Monitoreo del Ambiente , Contaminación del Agua/prevención & control , Agricultura , Animales , Cyprinidae/crecimiento & desarrollo , Ecosistema , Monitoreo del Ambiente/normas , Monitoreo del Ambiente/estadística & datos numéricos , Agua Dulce/química , Invertebrados/crecimiento & desarrollo , Irlanda , Oxígeno/metabolismo , Consumo de Oxígeno , Compuestos de Amonio Cuaternario/metabolismo , Salmonidae/crecimiento & desarrollo , Movimientos del Agua , Contaminantes Químicos del Agua/análisis , Contaminación del Agua/análisis , Contaminación Química del Agua/análisis , Contaminación Química del Agua/prevención & control , Abastecimiento de Agua/análisis , Abastecimiento de Agua/normas , Abastecimiento de Agua/estadística & datos numéricos
17.
Sci Total Environ ; 310(1-3): 87-99, 2003 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-12812733

RESUMEN

The scale and chronology of the phosphorus (P) enrichment of Lough Neagh, a large hypertrophic lake, was assessed using, as enrichment proxies, published palaeocological studies on diatoms and chironomid head capsules preserved in the lake sediments and, from 1974, monitoring data from the lake and its inflowing rivers. Enrichment commenced in 1880, and the scale and chronology of the diatom and chironomid records were similar up to 1960, but in the 1960s, chironomid accumulation rates increased dramatically, whereas diatom rates remained unchanged. From subsequent lake monitoring, the absence of a diatom response after 1960 was attributed to silica limitation so that P could be considered as the driver of increased diatom production only up to 1960. Using a coefficient for the demand for P by diatoms of 4 microg P mg SiO(2)(-1), it was calculated that the increased diatom production between 1881 and 1961 required an increase in lake P of 26 microg P l(-1). This value is close to the predicted increase of 22.5 microg P l(-1) in the lake caused by inputs of P from sewage treatment works and septic tanks. There was no evidence that diffuse source P contributed to enrichment over this period. Enrichment up to 1960 appears modest in comparison to subsequent years. From 1961 to 1974, lake P was estimated to have increased by 62 microg P l(-1), but only 25 microg P l(-1) of this increase was attributable to greater loadings of P from urban and septic tank sources. The enrichment response of chironomids at this time was also much greater than expected from a regression-derived relationship between urban P inputs and chironomid accumulation rates suggesting additional sources of P. The larger than expected increase in lake P was attributed to the onset of a significant internal loading of P and the commencement of an increase in diffuse source loadings of P. River monitoring has shown that diffuse P has increased steadily since 1974, more than counterbalancing a 40% reduction in urban P loadings that has taken place since 1980. By the end of the 20th century urban sources contributed only 19.7% of inflow P to Lough Neagh but lake P was 145 microg P l(-1) compared to an estimated concentration of 20 microg P l(-1) in 1881. Failure to control diffuse P sources has therefore been instrumental in the continued increase of lake P in Lough Neagh.


Asunto(s)
Chironomidae , Diatomeas , Eutrofización , Fósforo/análisis , Animales , Ciudades , Ecología , Irlanda , Dinámica Poblacional , Análisis de Regresión , Aguas del Alcantarillado
18.
Chemosphere ; 42(2): 215-20, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11237301

RESUMEN

Total phosphorus (P) river inputs and lake concentrations for the Neagh system in Northern Ireland are compared from the period 1974-1997. The main routes of P transfer between the lake water and the sediment are settlement of abiotic particles and planktonic diatoms, summer sediment release and re-sedimentation in the last months of the year. The annual river loading to the lake varied between 0.7 and 1.8 g P m(-2), and sediment release can be as much as 1.4 g P m(-2). A simple model evaluated the effect of sediment-water exchanges on the phosphorus available for spring phytoplankton growth. It showed that re-sedimentation of released P and washout over the winter greatly mitigated its effect. Correlation analysis demonstrated that the very large summer releases of sediment P were not related directly to the spring inputs from diatom settlement. No long-term trends in P release were seen.


Asunto(s)
Agua Dulce , Fósforo , Agua Dulce/química , Sedimentos Geológicos , Irlanda del Norte , Fósforo/análisis , Estaciones del Año
19.
Bioresour Technol ; 102(8): 5024-31, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21367602

RESUMEN

The aim of this study was to develop an input/output mass balance to predict phosphorus retention in a five pond constructed wetland system (CWS) at Greenmount Farm, County Antrim, Northern Ireland. The mass balance was created using 14-months of flow data collected at inflow and outflow points on a weekly basis. Balance outputs were correlated with meteorological parameters, such as daily air temperature and hydrological flow, recorded daily onsite. The mass balance showed that phosphorus retention within the system exceeded phosphorus release, illustrating the success of this CWS to remove nutrients from agricultural effluent from a dairy farm. The last pond, pond 5, showed the greatest relative retention of 86%. Comparison of retention and mean air temperature highlighted a striking difference in trends between up-gradient and down-gradient ponds, with up-gradient ponds 1 and 2 displaying a positive quadratic relationship and down-gradient ponds 3 through 5 displaying a negative quadratic relationship.


Asunto(s)
Industria Lechera , Restauración y Remediación Ambiental/métodos , Residuos Industriales , Fósforo/aislamiento & purificación , Humedales , Modelos Teóricos , Movimientos del Agua
20.
Sci Total Environ ; 409(11): 2211-21, 2011 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-21429559

RESUMEN

Functional relationships between phosphorus (P) discharge and concentration mechanisms were explored using a load apportionment model (LAM) developed for use in a freshwater catchment in Ireland with fourteen years of data (1995-2008). The aim of model conceptualisation was to infer changes in point and diffuse sources from catchment P loading during P mitigation, based upon a dataset comprising geospatial and water quality data from a 256km(2) lake catchment in an intensively farmed drumlin region of the midlands of Ireland. The model was calibrated using river total P (TP), molybdate reactive P (MRP) and runoff data from seven subcatchments. Temporal and spatial heterogeneity of P sources existed within and between subcatchments; these were attributed to differences in agricultural intensity, soil type and anthropogenically-sourced effluent P loading. Catchment rivers were sensitive to flow regime, which can result in eutrophication of rivers during summer and lake enrichment from frequent flood events. For one sewage impacted river, the LAM estimated that point sourced P contributed up to of 90% of annual MRP load delivered during a hydrological year and in this river point P sources dominated flows up to 92% of days. In the other rivers, despite diffuse P forming a majority of the annual P exports, point sources of P dominated flows for up to 64% of a hydrological year. The calibrated model demonstrated that lower P export rates followed specific P mitigation measures. The LAM estimated up to 80% decreases in point MRP load after enhanced P removal at waste water treatments plants in urban subcatchments and the implementation of septic tank and agricultural bye-laws in rural subcatchments. The LAM approach provides a way to assess the long-term effectiveness of further measures to reduce P loadings in EU (International) River Basin Districts and subcatchments.


Asunto(s)
Restauración y Remediación Ambiental/métodos , Modelos Químicos , Fósforo/análisis , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/prevención & control , Abastecimiento de Agua/estadística & datos numéricos , Monitoreo del Ambiente , Agua Dulce/química , Contaminación Química del Agua/estadística & datos numéricos , Abastecimiento de Agua/análisis
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