RESUMEN
This study presents an important long-term historical analysis of water quality in an internationally crucial waterway (the Solent, Hampshire, UK), in the context of increasing adoption of open-loop Exhaust Gas Cleaning Systems by shipping. The pollutants studied were acidification (pH), zinc, and benzo [a] pyrene, alongside temperature. We compared baseline sites to locations likely to be impacted by pollution. The Solent's average water temperature is slightly increasing, with temperatures at wastewater sites significantly higher. Acidification suggests a complex story, with a highly significant small overall increase in pH during the study period but significantly different values at wastewater and port sites. Zn concentrations have significantly reduced but increased in enclosed waters such as marinas. BaP showed no long-term trend with values at marinas significantly and consistently higher. The findings provide valuable long-term background data and insights that can feed into the upcoming review of the European Union's Marine Strategy Framework Directive and ongoing discussions about the regulation of, and future monitoring and management strategies for coastal/marine waterways.
Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Calidad del Agua , Monitoreo del Ambiente , Aguas Residuales , Contaminantes Ambientales/análisis , Emisiones de Vehículos/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
A long-term historical analysis of the impacts of recreational boating on marine surface water quality during a regatta (Cowes Week) in an internationally crucial waterway, the Solent Strait (Hampshire, UK) is presented. Water quality indicators studied included nitrogen concentration, bacterial indicators, and oxygen saturation, at three sampling sites at/near Cowes during 2001-2019. Findings include that sewage discharge from recreational boats is the key contributor to localised faecal contamination of marine surface waters, putting bathers and shellfisheries at risk. Bathing water quality monitoring and pollution warning systems should be strengthened prior to and during this type of regatta and access to bathing water areas may need to be restricted. These findings have implications for the regulation, future monitoring and management strategies for discharges from recreational boats during extended regattas. Adequate and affordable local facilities for recovering sewage wastewater from recreational boats should be provided alongside appropriate mechanisms for communication to sailors.
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Calidad del Agua , Deportes Acuáticos , Aguas del Alcantarillado/microbiología , Recreación , Bacterias , Microbiología del Agua , Monitoreo del AmbienteRESUMEN
The Manila clam (Ruditapes philippinarum), an invasive species in Northern Europe, can be used as a bioindicator of metal pollution. Seasonal effects on metallothionein (MT) production have not been considered in this species at the northernmost extent of its European distribution. This study assesses the annual seasonal effects on MT and metal concentrations in R. philippinarum from Poole Harbour, UK. R. philippinarum were collected in winter, spring, summer, and autumn throughout 2015, and MT and metal concentrations, as well as biotic and abiotic variables, were quantified. During winter, linear regression analysis showed significant positive relationships between tissue metal and MT concentrations. However, during spring and summer, these relationships were mostly insignificant. MT concentrations during spring had significant positive relationships with tissue and whole weight. Significant positive relationships were also observed between MT and condition index, during summer. During spring and summer, biotic factors seem to override the role of MT as a detoxification mechanism for metal exposure in this species. This is probably due to an increase in MT concentration in spring caused by gametogenesis, associated with increased tissue weight as the gonads expand. A depletion of energy resources, or physical stressors such as heat, may be attributed to the reduced MT production in clams of poor body condition in summer. The evidence from this study suggests that MT may only be a useful biomarker of metal pollution during winter in R. philippinarum in the UK. This verifies the natural variability of MT in this species at high latitudes, and highlights the potential and limits to a widely available bioindicator of metal pollution.
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Bivalvos/metabolismo , Metalotioneína/metabolismo , Metales/química , Estaciones del Año , Contaminantes Químicos del Agua/química , Animales , Monitoreo del Ambiente , Estuarios , Europa (Continente)RESUMEN
Metallothionein (MT) is established as a potentially useful biomarker for monitoring aquatic pollution. This paper addresses widespread inconsistencies in storage conditions, tissue type selection and pre-treatment of samples before MT and metal analysis in biomarker studies. This variation hampers comparability and so the widespread implementation of this monitoring approach. Actively sampled Mytilus edulis in Southampton Water, UK were exposed to different storage temperatures, a variety of tissue types were analysed, and various pre-treatments of transportation on ice, transportation in seawater, depuration, and rapid dissection in the field were examined. Storage temperatures of -20 °C were found to be adequate for periods of at least ten weeks, as MT was not reduced by protein degradation compared with samples kept at -80 °C. Whole tissue and digestive gland concentrations of MT and metals were significantly positively correlated and directly relatable. MT in the digestive gland appeared to be more responsive to metals than in whole tissue, where it may be diluted, masking MT responses. However, longer study periods may suffer the effects of mass changes to the digestive gland, which alters MT concentration, and it may therefore be advisable to measure whole tissue. Depuration and transportation in seawater reduced both MT and metal concentrations in the digestive gland, and few correlations between MT and metals were identified for these treatments. It is therefore recommended that: i) samples are transported to the laboratory on ice and dissected as soon as possible thereafter, ii) depuration should not be used when examining MT response to metal exposure until further research clarifying its utility is reported, iii) either whole tissue or the digestive gland can be used to measure MT, though whole tissue may be preferable on long-term studies, and iv) organisms can be stored at -20 °C before analysis for up to ten weeks. These practices can be applied to future biomonitoring studies and will improve the comparability and repeatability of using MT as a biomarker.
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Monitoreo del Ambiente/métodos , Metalotioneína/metabolismo , Metales/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , Organismos Acuáticos , Biomarcadores/metabolismo , Mytilus edulis , Agua de MarRESUMEN
Achieving food security in a 'perfect storm' scenario is a grand challenge for society. Climate change and an expanding global population act in concert to make global food security even more complex and demanding. As achieving food security and the millennium development goal (MDG) to eradicate hunger influences the attainment of other MDGs, it is imperative that we offer solutions which are complementary and do not oppose one another. Sustainable intensification of agriculture has been proposed as a way to address hunger while also minimizing further environmental impact. However, the desire to raise productivity and yields has historically led to a degraded environment, reduced biodiversity and a reduction in ecosystem services (ES), with the greatest impacts affecting the poor. This paper proposes that the ES framework coupled with a policy response framework, for example Driver-Pressure-State-Impact-Response (DPSIR), can allow food security to be delivered alongside healthy ecosystems, which provide many other valuable services to humankind. Too often, agro-ecosystems have been considered as separate from other natural ecosystems and insufficient attention has been paid to the way in which services can flow to and from the agro-ecosystem to surrounding ecosystems. Highlighting recent research in a large multi-disciplinary project (ASSETS), we illustrate the ES approach to food security using a case study from the Zomba district of Malawi.
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Agricultura/métodos , Cambio Climático , Conservación de los Recursos Naturales/métodos , Ecosistema , Abastecimiento de Alimentos/métodos , Crecimiento Demográfico , Agricultura/tendencias , Conservación de los Recursos Naturales/tendencias , MalauiRESUMEN
Poole Harbour is typical of many heavily anthropologically impacted semi-enclosed estuarine coastal areas under pressure from metal pollution across the world. This study examined the physiological significance of metal burdens within that sensitive area, and assessed the potential use of metallothionein (MT) concentrations in two organisms: the common cockle (Cerastoderma edule) and the Mermaid's glove sponge (Haliclona oculata) for mapping the spatial extent of the biological response to metal contamination. A spectrophotometric method was applied for detection of MT in the bivalve, and for the first time to detect MT in sponges. The results show that while some metal concentrations in cockle and sponge tissues and in their surrounding environment (water and sediment) could be related to sources of metal contamination, MT values in the soft tissue of cockles and whole tissue of sponges are not. No relation could be found between MT in both cockles and sponges, and any of the tested metals (As, Cd, Cr, Cu, Pb, Hg, Ni, Ag, Sn, Zn). Furthermore, some of the lowest MT concentrations were detected in heavily polluted areas, indicating that MT concentrations in tested organisms are not exclusively associated with metal concentrations, as other environmental factors could affect induction of this protein. Organisms probably have a high tolerance to metal contamination and chronic exposure to a high level of contamination resulted in developing a variety of detoxification mechanisms. Results indicate that further study of metal stress in this type of ecosystem may need to examine other indicator species and/or apply a different biomonitoring technique.
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Cardiidae/metabolismo , Monitoreo del Ambiente/métodos , Haliclona/metabolismo , Metalotioneína/metabolismo , Metales/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , Biomarcadores/metabolismo , EcosistemaRESUMEN
Data from 158 predominantly Angus fall-calving beef cows were used in 4 consecutive years to determine the effects of weaning date and cow age class on cow and calf performance. Treatments were arranged in a 2 x 2 factorial with 2 weaning dates and 2 age classes (young cows
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Bovinos/crecimiento & desarrollo , Preñez/fisiología , Destete , Animales , Peso al Nacer , Peso Corporal/fisiología , Bovinos/fisiología , Femenino , Lactancia/fisiología , Leche/química , Leche/metabolismo , Oklahoma , Embarazo , Reproducción/fisiología , Estaciones del Año , Factores de TiempoRESUMEN
Three experiments were conducted to evaluate the efficacy of supplemental energy and extruded-expelled cottonseed meal (ECSM; 30.6% CP; 44% NDF, 10.2% fat; DM basis) as a protein supplement (SUP) to spring-calving beef cows (n = 96; 535 kg initial BW; 5.4 initial BCS) consuming low-quality forage during late gestation and early lactation. Supplementation of ECSM was compared with 2 traditional cottonseed meal-based SUP. For all experiments, SUP provided equal CP. On a DM basis, SUP included 1) a blend of 76% wheat middlings and 18% solvent-extracted cottonseed meal (WMCSM); 2) solvent-extracted cottonseed meal (CSM); and 3) delinted, extruded-expelled cottonseed meal (ECSM). In Exp. 1, cows were individually fed SUP 3 d/wk until calving and 4 d/wk during lactation; total SUP period was 95 d. Tall-grass prairie hay (4.4% CP; 74% NDF; DM basis) was provided during the SUP period. Changes in cow BW during gestation (P = 0.23), over the SUP period (P = 0.27), and over the 301-d experiment (P = 0.56) were similar. Changes in BCS were similar during gestation (P = 0.78), over the SUP period (P = 0.95) and over the 301-d experiment (P = 0.37). Calf birth weights (P = 0.21) and BW at weaning (P = 0.76) were not different. Percentage of cows exhibiting luteal activity at the beginning of breeding season (P = 0.59), AI conception rate (P = 0.71), and pregnancy rate at weaning (P = 0.88) were not different. In Exp. 2, 18 cows in early lactation from Exp. 1 were used to determine the effect of SUP on hay intake and digestion. Hay intake tended (P = 0.10) to be greater for CSM than ECSM. Intake of OM and DM was greater for WMCSM (P
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Alimentación Animal/normas , Bovinos/fisiología , Aceite de Semillas de Algodón/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Suplementos Dietéticos , Ingestión de Energía/fisiología , Animales , Peso al Nacer/fisiología , Constitución Corporal/fisiología , Peso Corporal/fisiología , Bovinos/crecimiento & desarrollo , Bovinos/metabolismo , Digestión/fisiología , Ingestión de Alimentos/fisiología , Femenino , Lactancia/fisiología , Leche/química , Leche/metabolismo , Embarazo , Distribución Aleatoria , Reproducción/fisiología , Estaciones del AñoRESUMEN
The noncollagenous hexamer (NC1) domain of type IV collagen from Engelbreth-Holm-Swarm (EHS) sarcoma matrix was subjected to electrophoretic, amino-terminal amino acid sequence, and immunochemical analysis to determine which of the five known kinds of alpha(IV) chains are present. Electrophoretic analysis, whether by one-dimensional or two-dimensional electrophoresis, showed that nonlathyritic and lathyritic hexamer gave nearly identical patterns. Amino-terminal amino acid sequence analysis of hexamer subunits, transblotted from two-dimensional gels, revealed that the hexamer subunits were derived exclusively from the alpha 1 and alpha 2 chains. Western blots of hexamer subunits confirmed the sequence results, as the subunits. identified as alpha 1(IV) and alpha 2(IV) NC1 domains reacted with antibodies directed specifically against those subunits. Conversely, no reactivity of NC1 hexamer subunits was seen with Goodpasture serum, or with antibodies directed specifically against the alpha 3, alpha 4, and alpha 5 NC1 domains, confirming the lack of alpha 3, alpha 4, and alpha 5 chains. These results revealed that the type IV collagen component of the EHS sarcoma matrix is comprised exclusively of alpha 1 and alpha 2 chains. Its relative homogeneity simplifies, but restricts, interpretation of studies that employ it as a model type IV collagen because the studies would be based only on alpha 1 and alpha 2 chains.