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1.
Sci Total Environ ; 927: 171958, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38547970

RESUMEN

There is a need to understand what makes certain targeted measures for in-river phosphorus load reduction more effective than others. Therefore, this paper investigates multiple development scenarios in a small lowland polluted river draining an urban area (The Cut, Bracknell, UK), using an advection-dispersion model (ADModel-P). A comparative analysis is presented whereby changes in concentrations and fluxes of soluble reactive phosphorus (SRP) and organic phosphorus (OP) have been attributed to specific transformations (mineralization, sedimentation, resuspension, adsorption-desorption, and algal uptake) and correlated to controlling factors. Under present day conditions the river stretch is a net source of SRP (10.4 % increase in mean concentration) implying a release of previously accumulated material. Scenarios with the greatest impact are those based on managed reduction of phosphorus load in sources (e.g., 20 % increase in afforestation causes an in-river SRP and OP reduction of 1.3 % to 12.6 %) followed by scenarios involving changes in water temperature (e.g., 1 °C decrease leads to in-river SRP reduction around 3.1 %). Measures involving increased river residence time show the lowest effects (e.g., 16 % decrease in velocity results in under 0.02 % in-river SRP and OP reduction). For better understanding downstream persistence of phosphorus pollution and the effectiveness of mitigation measures the research demonstrates the importance of establishing when and where reaches are net adsorbers or desorbers, and whether sedimentation or resuspension is important.

2.
Sci Total Environ ; 921: 171148, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38401726

RESUMEN

Nature-based solutions have gained recognition for their potential to address urban environmental challenges, particularly in rapidly urbanising countries such as China. However, financial and spatial constraints hinder their widespread adoption. Here we explore urban residents' preferences for nature-based solutions targeting stormwater management, urban heat island reduction, and biodiversity support through monetary, time, and space contributions. We carried out three choice experiment surveys with 1536 Chinese respondents, employing three payment vehicles: willingness to pay (WTP), willingness to contribute time (WTCT), and a novel metric, willingness to contribute space (WTCS). The WTCS metric assesses individuals' willingness to voluntarily convert sealed surfaces on private land into greenspace. We found strong preferences for temperature and flooding reduction across all payment vehicles, reflecting substantial challenges of urban heat islands and flooding in China. Additionally, we reveal a preference for moderate greenspace management intensity, highlighting the potential for biodiversity benefits through reduced management intensities. The introduction of the WTCS payment vehicle expands the methodological toolkit for choice experiments and offers a novel approach to assess citizen support for nature-based solutions. These findings have practical implications for designing effective nature-based solutions programs to address urban environmental challenges and meet the preferences of urban residents in China and beyond.


Asunto(s)
Biodiversidad , Calor , Humanos , Ciudades , Encuestas y Cuestionarios , China , Ecosistema
3.
J Environ Manage ; 351: 119950, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38150927

RESUMEN

Amongst a spectrum of benefits, Nature-based Solutions (NBS) are increasingly being advocated as improving the quality of aquatic environments in urban areas. Of these, a widely adopted measure is tree planting. Yet, because of the local complexities and spatial variability of urban hydrological response, it is difficult to predict to what extent improvements in water quality will arise. To overcome this barrier, a standardised approach to process-based model simulation of urban river quality is described (QUESTOR-YARDSTICK (QUESTOR-YS)). The approach eliminates the influence of point sources of pollution and harmonises the way in which river hydrodynamics and contributory catchment size are represented. Thereby, it focuses on differences in water quality between cities due solely to climate, river discharge and urban diffuse nutrient pollution factors. The relative sensitivity to NBS establishment between urban water bodies in different cities anywhere across the world can also potentially be quantified. The method can be readily extended to include wastewater effluents. The validity of the approach is demonstrated for a small river in Birmingham, UK; and thence demonstrated for the case of 10 km of riparian tree planting in Birmingham, Oslo (Norway) and Aarhus (Denmark). Modelling suggests that riparian tree planting can substantially improve water quality in each example city for three key indicators of water quality in sensitive summer conditions (water temperature, chlorophyll-a and dissolved oxygen). Results show the level of benefit achievable in response to a fixed amount of planting will depend on the existing level of riparian tree occupancy.


Asunto(s)
Árboles , Calidad del Agua , Ciudades , Aguas Residuales , Temperatura , Ríos , Monitoreo del Ambiente
4.
Water Res ; 247: 120815, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37931359

RESUMEN

Riparian tree canopies are key components of river systems, and influence the provision of many essential ecosystem services. Their management provides the potential for substantial control of the downstream persistence of pollutants. The recent advent of new advances in mass spectrometry to detect a large suite of emerging contaminants, high-frequency observations of water quality and gas exchange (e.g., aquatic eddy covariance), and improved spatial resolution in remote sensing (e.g., hyperspectral measurements and high-resolution imagery), presents new opportunities to understand and more comprehensively quantify the role of riparian canopies as Nature-based Solutions. The paper outlines how we may now couple these advances in observational technologies with developments in water quality modelling to integrate simulation of eutrophication impacts with organic matter dynamics and fate of synthetic toxic compounds. In particular regarding solar radiation drivers, this enables us to scale-up new knowledge of canopy-mediated photodegradation processes at a basin level, and integrate it with ongoing improvements in understanding of thermal control, eutrophication, and ecosystem metabolism.


Asunto(s)
Ecosistema , Monitoreo del Ambiente , Monitoreo del Ambiente/métodos , Estuarios , Ciudades , Calidad del Agua
5.
Sci Total Environ ; 668: 470-484, 2019 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-30852223

RESUMEN

There are infinite possible future scenarios reflecting the impacts of anthropogenic multiple stress on our planet. These impacts include changes in climate and land cover, to which aquatic ecosystems are especially vulnerable. To assess plausible developments of the future state of European surface waters, we considered two climate scenarios and three storylines describing land use, management and anthropogenic development ('Consensus', 'Techno' and 'Fragmented', which in terms of environmental protection represent best-, intermediate- and worst-case, respectively). Three lake and four river basins were selected, representing a spectrum of European conditions through a range of different human impacts and climatic, geographical and biological characteristics. Using process-based and empirical models, freshwater total nitrogen, total phosphorus and chlorophyll-a concentrations were projected for 2030 and 2060. Under current conditions, the water bodies mostly fail good ecological status. In future predictions for the Techno and Fragmented World, concentrations further increased, while concentrations generally declined for the Consensus World. Furthermore, impacts were more severe for rivers than for lakes. Main pressures identified were nutrient inputs from agriculture, land use change, inadequately managed water abstractions and climate change effects. While the basins in the Continental and Atlantic regions were primarily affected by land use changes, in the Mediterranean/Anatolian the main driver was climate change. The Boreal basins showed combined impacts of land use and climate change and clearly reflected the climate-induced future trend of agricultural activities shifting northward. The storylines showed positive effects on ecological status by classical mitigation measures in the Consensus World (e.g. riparian shading), technical improvements in the Techno World (e.g. increasing wastewater treatment efficiency) and agricultural extensification in the Fragmented World. Results emphasize the need for implementing targeted measures to reduce anthropogenic impacts and the importance of having differing levels of ambition for improving the future status of water bodies depending on the societal future to be expected.

6.
J Mol Microbiol Biotechnol ; 28(3): 128-136, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30428476

RESUMEN

The efficiency and reproducibility of two-dimensional difference gel electrophoresis (2D DIGE) depends on several crucial steps: (i) adequate number of replicate gels, (ii) accurate image acquisition, and (iii) statistically confident protein abundance analysis. The latter is inherently determined by the image analysis system. Available software solutions apply different strategies for consecutive image alignment and protein spot detection. While DeCyderTM performs spot detection on single gels prior to the alignment of spot maps, SameSpotsTM completes image alignment in advance of spot detection. In this study, the performances of DeCyderTM and SameSpotsTM were compared considering all protein spots detected in 2D DIGE resolved proteomes of three different environmental bacteria with minimal user interference. Proteome map-based analysis by SameSpotsTM allows for fast and reproducible abundance change determination, avoiding time-consuming, manual spot matching. The different raw spot volumes, determined by the two software solutions, did not affect calculated abundance changes. Due to a slight factorial difference, minor abundance changes were very similar, while larger differences in the case of major abundance changes did not impact biological interpretation in the studied cases. Overall, affordable fluorescent dyes in combination with fast CCD camera-based image acquisition and user-friendly image analysis still qualify 2D DIGE as a valuable tool for quantitative proteomics.


Asunto(s)
Validación de Programas de Computación , Programas Informáticos , Electroforesis Bidimensional Diferencial en Gel/instrumentación , Electroforesis Bidimensional Diferencial en Gel/métodos , Procesamiento de Imagen Asistido por Computador/instrumentación , Procesamiento de Imagen Asistido por Computador/métodos , Proteoma , Proteómica/métodos , Reproducibilidad de los Resultados , Alineación de Secuencia , Flujo de Trabajo
7.
Zoo Biol ; 37(5): 360-368, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30182447

RESUMEN

As threats to migratory birds in the Western Hemisphere, including North America, intensify and bird populations decline, there is a growing interest among zoo biologists in the conservation and management of these taxa. The purpose of this article is to explore the role that Association of Zoos and Aquariums (AZA)-accredited zoos and aquariums either are playing or could play in the conservation and management of migratory birds. Topics explored include: (1) Public education and advocacy; (2) Captive breeding and reintroduction; (3) In situ conservation; (4) Tracking and monitoring; (5) Research/technology development; and (6) Sustainability/green practices; and (7) Partnerships. Zoos and aquariums could play an important role in increasing the public's access to understanding migratory birds and the threats they face, ultimately helping to protect these remarkable species.


Asunto(s)
Animales de Zoológico , Aves/clasificación , Conservación de los Recursos Naturales , Crianza de Animales Domésticos , Migración Animal , Animales , Aves/fisiología , Factores de Tiempo
8.
Sci Total Environ ; 613-614: 1510-1526, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-28886914

RESUMEN

Climate change is expected to increase eutrophication risk in rivers yet few studies identify the timescale or spatial extent of such impacts. Phosphorus concentration, considered the primary driver of eutrophication risk in English rivers, may increase through reduced dilution particularly if river flows are lower in summer. Detailed models can indicate change in catchment phosphorus concentrations but targeted support for mitigation measures requires a national scale evaluation of risk. In this study, a load apportionment model is used to describe the current relationship between flow and total reactive phosphorus (TRP) at 115 river sites across England. These relationships are used to estimate TRP concentrations for the 2050s under 11 climate change driven scenarios of future river flows and under scenarios of both current and higher levels of sewage treatment. National maps of change indicate a small but inconsistent increase in annual average TRP concentrations with a greater change in summer. Reducing the TRP concentration of final sewage effluent to 0.5mg/L P for all upstream sewage treatment works was inadequate to meet existing P standards required through the EU Water Framework Directive, indicating that more needs to be done, including efforts to reduce diffuse pollution.

9.
J Environ Manage ; 181: 172-184, 2016 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-27343434

RESUMEN

We present an integrated model of the direct consequences of climate change on land use, and the indirect effects of induced land use change upon the natural environment. The model predicts climate-driven shifts in the profitability of alternative uses of agricultural land. Both the direct impact of climate change and the induced shift in land use patterns will cause secondary effects on the water environment, for which agriculture is the major source of diffuse pollution. We model the impact of changes in such pollution on riverine ecosystems showing that these will be spatially heterogeneous. Moreover, we consider further knock-on effects upon the recreational benefits derived from water environments, which we assess using revealed preference methods. This analysis permits a multi-layered examination of the economic consequences of climate change, assessing the sequence of impacts from climate change through farm gross margins, land use, water quality and recreation, both at the individual and catchment scale.


Asunto(s)
Agricultura/economía , Cambio Climático , Ecosistema , Contaminación Ambiental , Modelos Teóricos , Clima , Ambiente , Recreación , Ríos/química , Reino Unido , Calidad del Agua
12.
Zoo Biol ; 32(1): 1-12, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22549966

RESUMEN

The global aquatic pet trade encompasses a wide diversity of freshwater and marine organisms. While relying on a continual supply of healthy, vibrant aquatic animals, few sustainability initiatives exist within this sector. Public aquariums overlap this industry by acquiring many of the same species through the same sources. End users are also similar, as many aquarium visitors are home aquarists. Here we posit that this overlap with the pet trade gives aquariums significant opportunity to increase the sustainability of the trade in aquarium fishes and invertebrates. Improving the sustainability ethos and practices of the aquatic pet trade can carry a conservation benefit in terms of less waste, and protection of intact functioning ecosystems, at the same time as maintaining its economic and educational benefits and impacts. The relationship would also move forward the goal of public aquariums to advance aquatic conservation in a broad sense. For example, many public aquariums in North America have been instrumental in working with the seafood industry to enact positive change toward increased sustainability. The actions include being good consumers themselves, providing technical knowledge, and providing educational and outreach opportunities. These same opportunities exist for public aquariums to partner with the ornamental fish trade, which will serve to improve business, create new, more ethical and more dependable sources of aquatic animals for public aquariums, and perhaps most important, possibly transform the home aquarium industry from a threat, into a positive force for aquatic conservation.


Asunto(s)
Acuicultura/métodos , Organismos Acuáticos , Comercio/economía , Conservación de los Recursos Naturales/métodos , Peces , Mascotas/economía , Animales , Conservación de los Recursos Naturales/economía , Árboles de Decisión , Especificidad de la Especie
13.
J Environ Manage ; 109: 19-26, 2012 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-22659646

RESUMEN

Observations of river flow, river quality and solar radiation were collated to assess the degree to which light and nutrients may be limiting phytoplankton growth at seven sites in the River Ouse catchment in NE England under average conditions. Hydraulic information derived from river network model applications was then used to determine where river water has sufficient residence time above the tidal limit to facilitate bloom development. A nitrate model (NALTRACES) was developed to estimate the impact of land management change on mean river nitrate concentrations. Applications of this model showed that although agricultural activity contributes substantially to nitrate loads in the Ouse it is likely to have little impact on phytoplankton growth, which could still occur extensively in its absence given favourable sunny and dry conditions. As an example of a means of controlling light availability, establishing full riparian tree cover would appear to be a considerably more effective management scenario than suppressing inputs to the river of nitrate or phosphorus. Any actions should be prioritised in headwater areas such as the upper reaches of the Swale and Ure tributaries. These conclusions are in broad agreement with those arising from more detailed simulations at daily resolution using the QUESTOR river quality model. The combination of simple modelling approaches applied here allows an initial identification of suitable spatially-targeted options for mitigating against phytoplankton blooms which can be applied more widely at a regional or national level.


Asunto(s)
Nitratos/química , Ríos , Contaminantes Químicos del Agua/química , Monitoreo del Ambiente , Contaminación Ambiental/prevención & control , Contaminación del Agua/prevención & control , Calidad del Agua
14.
J Biomed Opt ; 14(3): 030501, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19566285

RESUMEN

Tomographic imaging of a glioma tumor with endogenous fluorescence is demonstrated using a noncontact single-photon counting fan-beam acquisition system interfaced with microCT imaging. The fluorescence from protoporphyrin IX (PpIX) was found to be detectable, and allowed imaging of the tumor from within the cranium, even though the tumor presence was not visible in the microCT image. The combination of single-photon counting detection and normalized fluorescence to transmission detection at each channel allowed robust imaging of the signal. This demonstrated use of endogenous fluorescence stimulation from aminolevulinic acid (ALA) and provides the first in vivo demonstration of deep tissue tomographic imaging with protoporphyrin IX.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Fluorescencia , Glioma/diagnóstico por imagen , Microtomografía por Rayos X/métodos , Ácido Aminolevulínico , Animales , Humanos , Fármacos Fotosensibilizantes , Protoporfirinas , Ratas , Trasplante Heterólogo
15.
Rev Sci Instrum ; 80(4): 043701, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19405660

RESUMEN

A prototype small animal imaging system was created for coupling fluorescence tomography (FT) with x-ray microcomputed tomography (microCT). The FT system has the potential to provide synergistic information content resultant from using microCT images as prior spatial information and then allows overlay of the FT image onto the original microCT image. The FT system was designed to use single photon counting to provide maximal sensitivity measurements in a noncontact geometry. Five parallel detector locations are used, each allowing simultaneous sampling of the fluorescence and transmitted excitation signals through the tissue. The calibration and linearity range performance of the system are outlined in a series of basic performance tests and phantom studies. The ability to image protoporphyrin IX in mouse phantoms was assessed and the system is ready for in vivo use to study biological production of this endogenous marker of tumors. This multimodality imaging system will have a wide range of applications in preclinical cancer research ranging from studies of the tumor microenvironment and treatment efficacy for emerging cancer therapeutics.


Asunto(s)
Fluorescencia , Microtomografía por Rayos X/instrumentación , Animales , Calibración , Diseño de Equipo , Humanos , Procesamiento de Imagen Asistido por Computador , Modelos Lineales , Ratones , Fantasmas de Imagen , Reproducibilidad de los Resultados , Factores de Tiempo
16.
Conserv Biol ; 22(4): 815-6; author reply 816-8, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18637914
17.
Zoo Biol ; 27(6): 488-97, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19360642

RESUMEN

Scientific study within contemporary zoos and aquariums has developed ad hoc as an extremely broad, academically oriented mixture of basic and applied research spanning a wide array of concepts and disciplines. Several papers have considered prioritization of present or future research efforts within disciplines, but only a few have touched on prioritization across institutions, disciplines, and species. This lack of prioritization across institutions and disciplines is surprising given the growing interdependence of zoos and aquariums to maintain populations through exchange of animals, standardization of animal care procedures, and maintenance of self-sustaining populations. The purpose of this paper is to explore prioritization of scientific research, and support of that prioritized research, within and among the professionally managed zoo and aquarium members of the Association of Zoos and Aquariums (AZA). Zoo Biol 27:488-497, 2008. (c) 2008 Wiley-Liss, Inc.

18.
Bioorg Med Chem ; 14(9): 3002-10, 2006 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-16403639

RESUMEN

In vivo, 2-keto-3-deoxy-6-phosphogluconate (KDPG) aldolase catalyzes the reversible, stereospecific retro-aldol cleavage of KDPG to pyruvate and D-glyceraldehyde-3-phosphate. The enzyme is a lysine-dependent (Class I) aldolase that functions through the intermediacy of a Schiff base. Here, we propose a mechanism for this enzyme based on crystallographic studies of wild-type and mutant aldolases. The three dimensional structure of KDPG aldolase from the thermophile Thermotoga maritima was determined to 1.9A. The structure is the standard alpha/beta barrel observed for all Class I aldolases. At the active site Lys we observe clear density for a pyruvate Schiff base. Density for a sulfate ion bound in a conserved cluster of residues close to the Schiff base is also observed. We have also determined the structure of a mutant of Escherichia coli KDPG aldolase in which the proposed general acid/base catalyst has been removed (E45N). One subunit of the trimer contains density suggesting a trapped pyruvate carbinolamine intermediate. All three subunits contain a phosphate ion bound in a location effectively identical to that of the sulfate ion bound in the T. maritima enzyme. The sulfate and phosphate ions experimentally locate the putative phosphate binding site of the aldolase and, together with the position of the bound pyruvate, facilitate construction of a model for the full-length KDPG substrate complex. The model requires only minimal positional adjustments of the experimentally determined covalent intermediate and bound anion to accommodate full-length substrate. The model identifies the key catalytic residues of the protein and suggests important roles for two observable water molecules. The first water molecule remains bound to the enzyme during the entire catalytic cycle, shuttling protons between the catalytic glutamate and the substrate. The second water molecule arises from dehydration of the carbinolamine and serves as the nucleophilic water during hydrolysis of the enzyme-product Schiff base. The second water molecule may also mediate the base-catalyzed enolization required to form the carbon nucleophile, again bridging to the catalytic glutamate. Many aspects of this mechanism are observed in other Class I aldolases and suggest a mechanistically and, perhaps, evolutionarily related family of aldolases distinct from the N-acetylneuraminate lyase (NAL) family.


Asunto(s)
Aldehído-Liasas/química , Aldehído-Liasas/metabolismo , Aldehído-Liasas/clasificación , Aldehído-Liasas/genética , Sitios de Unión , Catálisis , Escherichia coli/enzimología , Escherichia coli/genética , Ácido Glutámico/genética , Ácido Glutámico/metabolismo , Modelos Moleculares , Estructura Cuaternaria de Proteína , Estructura Terciaria de Proteína , Especificidad por Sustrato , Thermotoga maritima/enzimología
20.
Conserv Biol ; 9(5): 1324-1326, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34261281
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