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1.
PLoS One ; 18(6): e0286679, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37279239

RESUMO

Attractive Targeted Sugar Baits (ATSB) have been demonstrated to result in significant reductions in malaria vector numbers in areas of scarce vegetation cover such as in Mali and Israel, but it is not clear whether such an effect can be replicated in environments where mosquitoes have a wide range of options for sugar resources. The current study evaluated the attractiveness of the predominant flowering plants of Asembo Siaya County, western Kenya in comparison to an ATSB developed by Westham Co. Sixteen of the most common flowering plants in the study area were selected and evaluated for relative attractiveness to malaria vectors in semi-field structures. Six of the most attractive flowers were compared to determine the most attractive to local Anopheles mosquitoes. The most attractive plant was then compared to different versions of ATSB. In total, 56,600 Anopheles mosquitoes were released in the semi-field structures. From these, 5150 mosquitoes (2621 males and 2529 females) of An. arabiensis, An. funestus and An. gambiae were recaptured on the attractancy traps. Mangifera indica was the most attractive sugar source for all three species while Hyptis suaveolens and Tephrosia vogelii were the least attractive plants to the mosquitoes. Overall, ATSB version 1.2 was significantly more attractive compared to both ATSB version 1.1 and Mangifera indica. Mosquitoes were differentially attracted to various natural plants in western Kenya and ATSB. The observation that ATSB v1.2 was more attractive to local Anopheles mosquitoes than the most attractive natural sugar source indicates that this product may be able to compete with natural sugar sources in western Kenya and suggests this product may have the potential to impact mosquito populations in the field.


Assuntos
Anopheles , Inseticidas , Magnoliopsida , Malária , Masculino , Animais , Feminino , Açúcares , Quênia , Controle de Mosquitos , Mosquitos Vetores , Carboidratos , Flores
3.
Sci Total Environ ; 825: 153955, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35189215

RESUMO

Adopting Regenerative Agriculture (RA) practices on temperate arable land can increase soil organic carbon (SOC) concentration without reducing crop yields. RA is therefore receiving much attention as a climate change mitigation strategy. However, estimating the potential change in national soil carbon stocks following adoption of RA practices is required to determine its suitability for this. Here, we use a well-validated model of soil carbon turnover (RothC) to simulate adoption of three regenerative practices (cover cropping, reduced tillage intensity and incorporation of a grass-based ley phase into arable rotations) across arable land in Great Britain (GB). We develop a modelling framework which calibrates RothC using studies of these measures from a recent systematic review, estimating the proportional increase in carbon inputs to the soil compared to conventional practice, before simulating adoption across GB. We find that cover cropping would on average increase SOC stocks by 10 t·ha-1 within 30 years of adoption across GB, potentially sequestering 6.5 megatonnes of carbon dioxide per year (MtCO2·y-1). Ley-arable systems could increase SOC stocks by 3 or 16 t·ha-1, potentially providing 2.2 or 10.6 MtCO2·y-1 of sequestration over 30 years, depending on the length of the ley-phase (one and four years, respectively, in these scenarios). In contrast, our modelling approach finds little change in soil carbon stocks when practising reduced tillage intensity. Our results indicate that adopting RA practices could make a meaningful contribution to GB agriculture reaching net zero greenhouse gas emissions despite practical constraints to their uptake.


Assuntos
Gases de Efeito Estufa , Solo , Agricultura/métodos , Carbono , Sequestro de Carbono , Mudança Climática
5.
Chemosphere ; 153: 294-306, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27023117

RESUMO

Historic mine sites are a major source of contamination to terrestrial and river environments. To demonstrate the importance of determining the significance of point and diffuse metal contamination and the related bioavailability of the metals present from abandoned mines a case study has been carried out. The study provides a quantitative assessment of a historic mine site, Wheal Betsy, southwest England, and its contribution to non-compliance with Water Framework Directive (WFD) Environmental Quality Standards (EQS) for Cd, Cu, Pb and Zn. Surface water and sediment samples showed significant negative environmental impacts even taking account of the bioavailability of the metal present, with lead concentration in the stream sediment up to 76 times higher than the Canadian sediment guidelines 'Probable Effect Level'. Benthic invertebrates showed a decline in species richness adjacent to the mine site with lead and cadmium the main cause. The main mine drainage adit was the single most significant source of metal (typically 50% of metal load from the area, but 88% for Ni) but the mine spoil tips north and south of the adit input added together discharged roughly an equivalent loading of metal with the exception of Ni. The bioavailability of metal in the spoil tips exhibited differing spatial patterns owing to varying ambient soil physico-chemistry. The data collected is essential to provide a clear understanding of the contamination present as well as its mobility and bioavailability, in order to direct the decision making process regarding remediation options and their likely effectiveness.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/análise , Mineração , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , Poluição Química da Água/análise , Cádmio/análise , Canadá , Cobre/análise , Inglaterra , Recuperação e Remediação Ambiental , Sedimentos Geológicos/química , Chumbo/análise , Rios , Água/química , Zinco/análise
6.
Nature ; 531(7593): 229-32, 2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26886790

RESUMO

The identification of properties that contribute to the persistence and resilience of ecosystems despite climate change constitutes a research priority of global relevance. Here we present a novel, empirical approach to assess the relative sensitivity of ecosystems to climate variability, one property of resilience that builds on theoretical modelling work recognizing that systems closer to critical thresholds respond more sensitively to external perturbations. We develop a new metric, the vegetation sensitivity index, that identifies areas sensitive to climate variability over the past 14 years. The metric uses time series data derived from the moderate-resolution imaging spectroradiometer (MODIS) enhanced vegetation index, and three climatic variables that drive vegetation productivity (air temperature, water availability and cloud cover). Underlying the analysis is an autoregressive modelling approach used to identify climate drivers of vegetation productivity on monthly timescales, in addition to regions with memory effects and reduced response rates to external forcing. We find ecologically sensitive regions with amplified responses to climate variability in the Arctic tundra, parts of the boreal forest belt, the tropical rainforest, alpine regions worldwide, steppe and prairie regions of central Asia and North and South America, the Caatinga deciduous forest in eastern South America, and eastern areas of Australia. Our study provides a quantitative methodology for assessing the relative response rate of ecosystems--be they natural or with a strong anthropogenic signature--to environmental variability, which is the first step towards addressing why some regions appear to be more sensitive than others, and what impact this has on the resilience of ecosystem service provision and human well-being.


Assuntos
Aclimatação , Mudança Climática , Ecossistema , Mapeamento Geográfico , Fenômenos Fisiológicos Vegetais , América , Regiões Árticas , Ásia , Austrália , Monitoramento Ambiental , Atividades Humanas , Modelos Teóricos , Floresta Úmida , Temperatura , Fatores de Tempo , Árvores , Água/análise
7.
Ecol Evol ; 5(21): 5057-74, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26640682

RESUMO

Population-level studies of how tit species (Parus spp.) track the changing phenology of their caterpillar food source have provided a model system allowing inference into how populations can adjust to changing climates, but are often limited because they implicitly assume all individuals experience similar environments. Ecologists are increasingly using satellite-derived data to quantify aspects of animals' environments, but so far studies examining phenology have generally done so at large spatial scales. Considering the scale at which individuals experience their environment is likely to be key if we are to understand the ecological and evolutionary processes acting on reproductive phenology within populations. Here, we use time series of satellite images, with a resolution of 240 m, to quantify spatial variation in vegetation green-up for a 385-ha mixed-deciduous woodland. Using data spanning 13 years, we demonstrate that annual population-level measures of the timing of peak abundance of winter moth larvae (Operophtera brumata) and the timing of egg laying in great tits (Parus major) and blue tits (Cyanistes caeruleus) is related to satellite-derived spring vegetation phenology. We go on to show that timing of local vegetation green-up significantly explained individual differences in tit reproductive phenology within the population, and that the degree of synchrony between bird and vegetation phenology showed marked spatial variation across the woodland. Areas of high oak tree (Quercus robur) and hazel (Corylus avellana) density showed the strongest match between remote-sensed vegetation phenology and reproductive phenology in both species. Marked within-population variation in the extent to which phenology of different trophic levels match suggests that more attention should be given to small-scale processes when exploring the causes and consequences of phenological matching. We discuss how use of remotely sensed data to study within-population variation could broaden the scale and scope of studies exploring phenological synchrony between organisms and their environment.

8.
Ecol Appl ; 25(5): 1290-302, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26485956

RESUMO

The local ecological footprinting tool (LEFT) uses globally available databases, modeling, and algorithms to, remotely assess locally important ecological features across landscapes based on five criteria: biodiversity (beta-diversity), vulnerability (threatened species), fragmentation, connectivity, and resilience. This approach can be applied to terrestrial landscapes at a 300-m resolution within a given target area. Input is minimal (latitude and longitude) and output is a computer-generated report and series of maps that both individually and synthetically depict the relative value of each ecological criteria. A key question for any such tool, however, is how representative is the remotely obtained output compared to what is on the ground. Here, we present the results from comparing remotely- vs. field-generated outputs from the LEFT tool on two distinct study areas for beta-diversity and distribution of threatened species (vulnerability), the two fields computed by LEFT for which such an approach is feasible. The comparison method consists of a multivariate measure of similarity between two fields based on discrete wavelet transforms, and reveals consistent agreement across a wide range of spatial scales. These results suggest that remote assessment tools such as LEFT hold great potential for determining key ecological features across landscapes and for being utilized in preplanning biodiversity assessment tools.


Assuntos
Biodiversidade , Astronave , Cidades , Bases de Dados Factuais , Monitoramento Ambiental , Incerteza
9.
Health Aff (Millwood) ; 33(11): 2003-11, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25367996

RESUMO

Implementation of the Affordable Care Act is unleashing historic new efforts aimed at reforming the US health system. Many important incremental improvements are under way, yet there is a growing recognition that more transformative changes are necessary if the health care system is to do a better job of optimizing population health. While the concept of the Triple Aim-dedicated to improving the experience of care, the health of populations, and lowering per capita costs of care-has been used to help health care providers and health care systems focus their efforts on costs, quality, and outcomes, it does not provide a roadmap for a new system. In this article we describe the 3.0 Transformation Framework we developed to stimulate thinking and support the planning and development of the new roadmap for the next generation of the US health care system. With a focus on optimizing population health over the life span, the framework suggests how a system designed to better manage chronic disease care could evolve into a system designed to enhance population health. We describe how the 3.0 Transformation Framework has been used and applied in national, state, and local settings, and we suggest potential next steps for its wider application and use.


Assuntos
Atenção à Saúde/tendências , Difusão de Inovações , Reforma dos Serviços de Saúde , Planejamento em Saúde , Melhoria de Qualidade , Humanos , Patient Protection and Affordable Care Act , Estados Unidos
10.
J Health Polit Policy Law ; 38(4): 841-5, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23922362

RESUMO

At a November 2012 workshop, state health policy officials, other Medicaid and insurance exchange practitioners, and health policy researchers discussed issues surrounding the implementation and sustainability of Medicaid expansion and insurance exchange coordination under the Patient Protection and Affordable Care Act (PPACA). Foremost were concerns about (1) intergovernmental relations (states experiencing uncertain information, lack of coordination among federal agencies, and limited resources to take on new responsibilities under the PPACA), and (2) policy design (new issues such as Medicaid exchange coordination on top of preexisting Medicaid challenges). JHPPL has proposed the creation of a research network to develop policy options and share strategies and best practices.


Assuntos
Política de Saúde , Medicaid/organização & administração , Patient Protection and Affordable Care Act/organização & administração , Política , Reforma dos Serviços de Saúde , Humanos , Medicaid/economia , Medicaid/legislação & jurisprudência , Patient Protection and Affordable Care Act/economia , Patient Protection and Affordable Care Act/legislação & jurisprudência , Estados Unidos
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