17 research outputs found

    The Relative Impact of Climate Change on the Extinction Risk of Tree Species in the Montane Tropical Andes.

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    There are widespread concerns that anthropogenic climate change will become a major cause of global biodiversity loss. However, the potential impact of climate change on the extinction risk of species remains poorly understood, particularly in comparison to other current threats. The objective of this research was to examine the relative impact of climate change on extinction risk of upper montane tree species in the tropical Andes, an area of high biodiversity value that is particularly vulnerable to climate change impacts. The extinction risk of 129 tree species endemic to the region was evaluated according to the IUCN Red List criteria, both with and without the potential impacts of climate change. Evaluations were supported by development of species distribution models, using three methods (generalized additive models, recursive partitioning, and support vector machines), all of which produced similarly high AUC values when averaged across all species evaluated (0.82, 0.86, and 0.88, respectively). Inclusion of climate change increased the risk of extinction of 18-20% of the tree species evaluated, depending on the climate scenario. The relative impact of climate change was further illustrated by calculating the Red List Index, an indicator that shows changes in the overall extinction risk of sets of species over time. A 15% decline in the Red List Index was obtained when climate change was included in this evaluation. While these results suggest that climate change represents a significant threat to tree species in the tropical Andes, they contradict previous suggestions that climate change will become the most important cause of biodiversity loss in coming decades. Conservation strategies should therefore focus on addressing the multiple threatening processes currently affecting biodiversity, rather than focusing primarily on potential climate change impacts

    Geographical distribution of fertility rates in 70 low-income, lower-middle-income, and upper-middle-income countries, 2010–16: a subnational analysis of cross-sectional surveys

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    Background Understanding subnational variation in age-specific fertility rates (ASFRs) and total fertility rates (TFRs), and geographical clustering of high fertility and its determinants in low-income and middle-income countries, is increasingly needed for geographical targeting and prioritising of policy. We aimed to identify variation in fertility rates, to describe patterns of key selected fertility determinants in areas of high fertility. Methods We did a subnational analysis of ASFRs and TFRs from the most recent publicly available and nationally representative cross-sectional Demographic and Health Surveys and Multiple Indicator Cluster Surveys collected between 2010 and 2016 for 70 low-income, lower-middle-income, and upper-middle-income countries, across 932 administrative units. We assessed the degree of global spatial autocorrelation by using Moran's I statistic and did a spatial cluster analysis using the Getis-Ord Gi* local statistic to examine the geographical clustering of fertility and key selected fertility determinants. Descriptive analysis was used to investigate the distribution of ASFRs and of selected determinants in each cluster. Findings TFR varied from below replacement (2·1 children per women) in 36 of the 932 subnational regions (mainly located in India, Myanmar, Colombia, and Armenia), to rates of 8 and higher in 14 subnational regions, located in sub-Saharan Africa and Afghanistan. Areas with high-fertility clusters were mostly associated with areas of low prevalence of women with secondary or higher education, low use of contraception, and high unmet needs for family planning, although exceptions existed. Interpretation Substantial within-country variation in the distribution of fertility rates highlights the need for tailored programmes and strategies in high-fertility cluster areas to increase the use of contraception and access to secondary education, and to reduce unmet need for family planning. Funding Wellcome Trust, the UK Foreign, Commonwealth and Development Office, and the Bill & Melinda Gates Foundation

    A review of geospatial methods for population estimation and their use in constructing reproductive, maternal, newborn, child and adolescent health service indicators

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    Background Household survey data are frequently used to measure reproductive, maternal, newborn, child and adolescent health (RMNCAH) service utilisation in low and middle income countries. However, these surveys are typically only undertaken every 5 years and tend to be representative of larger geographical administrative units. Investments in district health management information systems (DHMIS) have increased the capability of countries to collect continuous information on the provision of RMNCAH services at health facilities. However, reliable and recent data on population distributions and demographics at subnational levels necessary to construct RMNCAH coverage indicators are often missing. One solution is to use spatially disaggregated gridded datasets containing modelled estimates of population counts. Here, we provide an overview of various approaches to the production of gridded demographic datasets and outline their potential and their limitations. Further, we show how gridded population estimates can be used as alternative denominators to produce RMNCAH coverage metrics in combination with data from DHMIS, using childhood vaccination as examples. Methods We constructed indicators on the percentage of children one year old for diphtheria, pertussis and tetanus vaccine dose 3 (DTP3) and measles vaccine dose (MCV1) in Zambia and Nigeria at district levels. For the numerators, information on vaccines doses was obtained from each country’s respective DHMIS. For the denominators, the number of children was obtained from 3 different sources including national population projections and aggregated gridded estimates derived using top-down and bottom-up geospatial methods. Results In Zambia, vaccination estimates utilising the bottom-up approach to population estimation substantially reduced the number of districts with > 100% coverage of DTP3 and MCV1 compared to estimates using population projection and the top-down method. In Nigeria, results were mixed with bottom-up estimates having a higher number of districts > 100% and estimates using population projections performing better particularly in the South. Conclusions Gridded demographic data utilising traditional and novel data sources obtained from remote sensing offer new potential in the absence of up to date census information in the estimation of RMNCAH indicators. However, the usefulness of gridded demographic data is dependent on several factors including the availability and detail of input data

    Measuring the availability and geographical accessibility of maternal health services across sub-Saharan Africa

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    BACKGROUND: With universal health coverage a key component of the 2030 Sustainable Development Goals, targeted monitoring is crucial for reducing inequalities in the provision of services. However, monitoring largely occurs at the national level, masking sub-national variation. Here, we estimate indicators for measuring the availability and geographical accessibility of services, at national and sub-national levels across sub-Saharan Africa, to show how data at varying spatial scales and input data can considerably impact monitoring outcomes. METHODS: Availability was estimated using the World Health Organization guidelines for monitoring emergency obstetric care, defined as the number of hospitals per 500,000 population. Geographical accessibility was estimated using the Lancet Commission on Global Surgery, defined as the proportion of pregnancies within 2 h of the nearest hospital. These were calculated using geo-located hospital data for sub-Saharan Africa, with their associated travel times, along with small area estimates of population and pregnancies. The results of the availability analysis were then compared to the results of the accessibility analysis, to highlight differences between the availability and geographical accessibility of services. RESULTS: Despite most countries meeting the targets at the national level, we identified substantial sub-national variation, with 58% of the countries having at least one administrative unit not meeting the availability target at province level and 95% at district level. Similarly, 56% of the countries were found to have at least one province not meeting the accessibility target, increasing to 74% at the district level. When comparing both availability and accessibility within countries, most countries were found to meet both targets; however sub-nationally, many countries fail to meet one or the other. CONCLUSION: While many of the countries met the targets at the national level, we found large within-country variation. Monitoring under the current guidelines, using national averages, can mask these areas of need, with potential consequences for vulnerable women and children. It is imperative therefore that indicators for monitoring the availability and geographical accessibility of health care reflect this need, if targets for universal health coverage are to be met by 2030

    A zero-dose vulnerability index for equity assessment and spatial prioritization in low- and middle-income countries

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    Many low- and middle-income countries (LMICs) continue to experience substantial inequities in vaccination coverage despite recent efforts to reach missed communities and reduce zero-dose prevalence. Geographic inequities in vaccination coverage are often characterized by a multiplicity of risk factors which should be operationalized through data integration to inform more effective and equitable vaccination policies and programmes. Here, we explore approaches for integrating information from multiple risk factors to create a zero-dose vulnerability index to improve the identification and prioritization of vulnerable communities and understanding of inequities in vaccination coverage. We assembled geolocated data on vaccination coverage and associated risk factors in six LMICs, focusing on the coverage of DTP1, DTP3 and MCV1 vaccines as indicators of zero dose and under-vaccination. Using geospatial modelling techniques built on a suite of geospatial covariate information, we produced 1 × 1 km and district level maps of the previously unmapped risk factors and vaccination coverage. We then integrated data from the maps of the risk factors using different approaches to construct a zero-dose vulnerability index to classify districts within the countries into different vulnerability groups, ranging from the least vulnerable (1) to the most vulnerable (5) areas. Through integration with population data, we estimated numbers of children aged under 1 living within the different vulnerability classes. Our results show substantial variation in the spatial distribution of the index, revealing the most vulnerable areas despite little variation in coverage in some cases. We found that the most distinguishing characteristics of the most vulnerable areas cut across the different subdomains (health, socioeconomic, demographic and geographic) of the risk factors included in our study. We also demonstrated that the index can be robustly estimated with fewer risk factors and without linkage to information on vaccination coverage. The index constitutes a practical and effective tool to guide targeted vaccination strategies in LMICs.</p

    Spatiotemporal incidence of Zika and associated environmental drivers for the 2015-2016 epidemic in Colombia.

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    Despite a long history of mosquito-borne virus epidemics in the Americas, the impact of the Zika virus (ZIKV) epidemic of 2015–2016 was unexpected. The need for scientifically informed decision-making is driving research to understand the emergence and spread of ZIKV. To support that research, we assembled a data set of key covariates for modeling ZIKV transmission dynamics in Colombia, where ZIKV transmission was widespread and the government made incidence data publically available. On a weekly basis between January 1, 2014 and October 1, 2016 at three administrative levels, we collated spatiotemporal Zika incidence data, nine environmental variables, and demographic data into a single downloadable database. These new datasets and those we identified, processed, and assembled at comparable spatial and temporal resolutions will save future researchers considerable time and effort in performing these data processing steps, enabling them to focus instead on extracting epidemiological insights from this important data set. Similar approaches could prove useful for filling data gaps to enable epidemiological analyses of future disease emergence events

    Evaluación del estado de conservación de los bosques montanos en los Andes tropicales

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    The tropical Andes is a unique region with high habitat diversity, resulting from complex climatic and spatial gradients. Andean montane forests are currently a major global conservation priority owing to their high species richness and high level of endemism. Nonetheless they are considered one of the least known ecosystems in the tropics, but the breath of ecosystem services that these forests provide, including the regulation of regional climate and the capture and storage of carbon, is widely recognised. This article presents an overview of the conservation status of tropical Andean montane forests and the challenges it entails. It also provides information on threats, including the identification of those that are most likely to be responsible for increasing the extinction risk for many species. It highlights the need for acquiring more information on the conservation status of species as to identify future priorities for conservation in the region. The recent initiative "Red List and conservation planning for montane tree species of the Tropical Andes," made of delegates from several countries in the region, will provide a solid basis for developing policies and managing responses aimed at reducing deforestation and species loss in these forests, including actions to promote the creation of protected areas, forest restoration and sustainable forest management.</p

    Evaluation of the conservation status of montane forest in the tropical Andes

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    Los Andes tropicales constituyen una región única con una alta diversidad de hábitats, producto de complejos gradientes espaciales y ambientales. Los bosques montanos de esta región son considerados como una prioridad global de conservación, debido principalmente a su elevada riqueza biológica y de endemismos. Sin embargo su biodiversidad es de las menos conocidas de toda la región tropical, aunque se reconoce la amplia gama de servicios ambientales que prestan, incluyendo la regulación del clima regional y la captura y almacenamiento de carbono. Este artículo ofrece una perspectiva general del estado de conservación de los bosques montanos tropicales andinos y de los retos que esta implica. Asimismo, proporciona información sobre sus amenazas, identificando aquéllas que con mayor probabilidad sean responsables de aumentar el riesgo de extinción de especies. Se resalta la necesidad de disponer de más información sobre el estado de conservación de las especies para identificar las futuras prioridades de conservación en la región. La reciente iniciativa de la "Lista Roja y planeación para la conservación de especies de árboles montanos de los Andes Tropicales", formada por delegados de varios países de la región, constituirá una sólida base para el desarrollo y enfoque de políticas y respuestas de manejo dirigidas a la reducción de la deforestación y pérdida de especies en estos bosques, incluyendo acciones para promover la creación de áreas protegidas, restauración forestal y manejo forestal sostenible.The tropical Andes is a unique region with high habitat diversity, resulting from complex climatic and spatial gradients. Andean montane forests are currently a major global conservation priority owing to their high species richness and high level of endemism. Nonetheless they are considered one of the least known ecosystems in the tropics, but the breath of ecosystem services that these forests provide, including the regulation of regional climate and the capture and storage of carbon, is widely recognised. This article presents an overview of the conservation status of tropical Andean montane forests and the challenges it entails. It also provides information on threats, including the identification of those that are most likely to be responsible for increasing the extinction risk for many species. It highlights the need for acquiring more information on the conservation status of species as to identify future priorities for conservation in the region. The recent initiative "Red List and conservation planning for montane tree species of the Tropical Andes," made of delegates from several countries in the region, will provide a solid basis for developing policies and managing responses aimed at reducing deforestation and species loss in these forests, including actions to promote the creation of protected areas, forest restoration and sustainable forest management.Fil: Tejedor Garavito, N. Bournemouth University; Reino UnidoFil: Álvarez, E.. Instituto de Investigación de Recursos Biológicos Alexander von Humboldt; Colombia. Jardín Botánico de Medellín; ColombiaFil: Arango Caro, S.. Missouri Botanical Garden; Estados UnidosFil: Araujo Murakami, A.. Universidad Autónoma Gabriel Rene Moreno; BoliviaFil: Blundo, Cecilia Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Fundación Pro Yungas. Tucumán; ArgentinaFil: Boza Espinoza, T. E.. Missouri Botanical Garden; Estados UnidosFil: La Torre Cuadros, M. A.. Universidad Nacional Agraria La Molina; Perú. World Agroforestry Centre; PerúFil: Gavira, J.. Universidad de los Andes; VenezuelaFil: Gutiérrez, N.. Universidad de los Andes; VenezuelaFil: Jørgensen, P. M.. Missouri Botanical Garden; Estados UnidosFil: León, B.. University of Texas at Austin; Estados Unidos. Universidad Nacional Mayor de San Marcos; PerúFil: López Camacho, R.. Universidad Distrital Francisco José de Caldas; ColombiaFil: Malizia, Lucio Ricardo. Universidad Nacional de Jujuy. Facultad de Ciencias Agrarias; Argentina. Fundación ProYungas; ArgentinaFil: Millán, B.. Universidad Nacional Mayor de San Marcos,; BoliviaFil: Moraes, M.. Universidad Mayor de San Andrés; BoliviaFil: Pacheco, S.. Fundación ProYungas; ArgentinaFil: Rey Benayas, J. M.. Universidad de Alcalá; EspañaFil: Reynel, C.. Universidad Nacional Agraria La Molina; PerúFil: Timaná de la Flor, M.. Pontificia Universidad Católica de Perú; PerúFil: Ulloa Ulloa, C.. Missouri Botanical Garden; Estados UnidosFil: Vacas Cruz, O.. Pontificia Universidad Católica del Ecuador; EcuadorFil: Newton, A. C.. Bournemouth University; Reino Unid
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