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1.
Environ Res ; 233: 116510, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37385415

RESUMO

Fire regimes in mountain landscapes of southern Europe have been shifting from their baselines due to rural abandonment and fire exclusion policies. Understanding the effects of fire on biodiversity is paramount to implement adequate management. Herein, we evaluated the relative role of burn severity and heterogeneity on bird abundance in an abandoned mountain range located in the biogeographic transition between the Eurosiberian and Mediterranean region (the Natural Park 'Baixa Limia-Serra do Xurés'). We surveyed the bird community in 206 census plots distributed across the Natural Park, both inside and outside areas affected by wildfires over the last 11 years (from 2010 to 2020). We used satellite images of Sentinel 2 and Landsat missions to quantify the burn severity and heterogeneity of each fire within each surveyed plot. We also accounted for the past land use (forestry or agropastoral use) by using a land cover information for year 2010 derived from satellite image classification. We recorded 1735 contacts from 28 bird species. Our models, fitted by using GLMs with Poisson error distribution (pseudo-R2-average of 0.22 ± 0.13), showed that up to 71% of the modeled species were linearly correlated with at least one attribute of the fire regime. The spatiotemporal variation in burnt area and severity were relevant factors for explaining the local abundance of our target species (39% of the species; Akaike weights >0.75). We also found a quadratic effect of at least one fire regime attribute on bird abundance for 60% of the modeled species. The past land use, and its legacy after 10 years, was critical to understand the role of fire (Akaike weights >0.75). Our findings confirm the importance of incorporating remotely sensed indicators of burn severity into the toolkit of decision makers to accurately anticipate the response of birds to fire management.


Assuntos
Queimaduras , Incêndios , Incêndios Florestais , Animais , Florestas , Aves/fisiologia , Ecossistema
2.
Animals (Basel) ; 11(7)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34359148

RESUMO

Despite the mounting evidence supporting positive relationships between species abundance and habitat suitability, the capacity of ecological niche models (ENMs) to capture variations in population abundance remains largely unexplored. This study focuses on sympatric populations of hen harrier (Circus cyaneus) and Montagu's harrier (Circus pygargus), surveyed in 1997 and 2017 in an upland moor area in northwestern Spain. The ENMs performed very well for both species (with area under the ROC curve and true skill statistic values of up to 0.9 and 0.75). The presence of both species was mainly correlated with heathlands, although the normalized difference water index derived from Landsat images was the most important for hen harrier, indicating a greater preference of this species for wet heaths and peat bogs. The findings showed that ENM-derived habitat suitability was significantly correlated with the species abundance, thus reinforcing the use of ENMs as a proxy for species abundance. However, the temporal variation in species abundance was not significantly explained by changes in habitat suitability predicted by the ENMs, indicating the need for caution when using these types of models to infer changes in population abundance.

3.
PLoS One ; 12(7): e0181769, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28738072

RESUMO

Monitoring protected areas (PAs) is essential for systematic evaluation of their effectiveness in terms of habitat protection, preservation and representativeness. This study illustrates how the use of species distribution models that combine remote sensing data and information about biodiversity surrogates can contribute to develop a systematic protocol for monitoring PAs. In particular, we assessed the effectiveness of the Natura 2000 (N2000) network, for conserving and preserving the representativeness of seven raptor species in a highly-dynamic landscape in northwest Spain between 2001 and 2014. We also evaluated the cost-effectiveness of the N2000 network by using the total area under protection as a proxy for conservation costs. Overall, the N2000 network was found to poorly represent the habitats of the raptor species. Despite the low representativeness, this network showed a high degree of effectiveness due to increased overall habitat availability for generalist and forest specialist species between 2001 and 2014. Nevertheless, additional protected areas should be established in the near future to increase their representativeness, and thus ensure the protection of open-habitat specialist species and their priority habitats. In addition, proactive conservation measures in natural and semi-natural ecosystems (in particular, montane heathlands) will be essential for long-term protection of Montagu's harrier (species listed in the Annex I of the Bird Directive), and thus complying with the current European Environmental Legislation. This study sheds light on how the development and application of new protected area indices based on the combined use of freely-available satellite data and species distribution models may contribute substantially to the cost-efficiency of the PA monitoring systems, and to the 'Fitness Check' process of EU Nature Directives.


Assuntos
Conservação dos Recursos Naturais/métodos , Aves Predatórias/fisiologia , Animais , Biodiversidade , Ecossistema , Espanha
4.
P R Health Sci J ; 36(1): 17-23, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28266695

RESUMO

OBJECTIVE: The reported cesarean delivery (CD) rate for 2012 in Puerto Rico was higher than that of the United States (48.5% and 32.8%, respectively). Multiple reasons for and consequences of the high rates of CD exist. The decision to perform a CD is based on multiple factors, some of which are not obstetrical. In order to better understand those factors, the pilot study described in this manuscript analyzed data collected from obstetricians themselves. METHODS: During 2011, convenience sampling was used to collect data from active obstetric practitioners attending the Caribe Gyn 2011 conference in Ponce, Puerto Rico. A self-administered survey was piloted and analyzed using formative content analysis. Obstetricians were asked to name factors that contribute to their decision to perform a CD and factors they felt influence other obstetricians to make that decision. RESULTS: In general, common maternal and fetal causes for choosing CD were noted. Hypertensive disorders (60%) and abnormal intrapartum fetal tracing (83%) were highly rated, as were non-obstetrical factors, including physician convenience (52%) and concern for medical liability for vaginal delivery (50%). CONCLUSION: According to the participating obstetricians, many factors associated with the standard practice of obstetrics influence the decision to perform a CD. However, non-obstetrical reasons were also found. Future studies using a larger sample of Puerto Rican obstetricians are required to fully understand these factors in order to both address them through educational interventions for patients, physicians, administrators, and insurers, and inform public policy.


Assuntos
Cesárea/estatística & dados numéricos , Tomada de Decisões , Obstetrícia/estatística & dados numéricos , Médicos/estatística & dados numéricos , Adulto , Idoso , Atitude do Pessoal de Saúde , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Gravidez , Complicações na Gravidez/epidemiologia , Porto Rico
5.
Bioresour Technol ; 142: 115-20, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23743423

RESUMO

The aim of this paper was to study the evolution of DOM during 1 year of observation in simulated landfill, of aerobically treated vs. untreated organic fraction of MSW. Results obtained indicated that aerobic treatment of organic fraction of MSW permitted getting good biological stability so that, successive incubation under anaerobic condition in landfill allowed biological process to continue getting a strong reduction of soluble organic matter (DOM) that showed, also, an aromatic character. Incubation of untreated waste gave similar trend, but in this case DOM decreasing was only apparent as inhibition of biological process in landfill did not allow replacing degraded/leached DOM with new material coming from hydrolysis of fresh OM.


Assuntos
Compostos Orgânicos/química , Instalações de Eliminação de Resíduos , Aerobiose , Biodegradação Ambiental , Análise Espectral/métodos
6.
Bioresour Technol ; 143: 131-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23792663

RESUMO

The aim of this work was to evaluate the effects of full scale MBT process (28 d) in removing inhibition condition for successive biogas (ABP) production in landfill and in reducing total waste impact. For this purpose the organic fraction of MSW was treated in a full-scale MBT plant and successively incubated vs. untreated waste, in simulated landfills for one year. Results showed that untreated landfilled-waste gave a total ABP reduction that was null. On the contrary MBT process reduced ABP of 44%, but successive incubation for one year in landfill gave a total ABP reduction of 86%. This ABP reduction corresponded to a MBT process of 22 weeks length, according to the predictive regression developed for ABP reduction vs. MBT-time. Therefore short MBT allowed reducing landfill impact, preserving energy content (ABP) to be produced successively by bioreactor technology since pre-treatment avoided process inhibition because of partial waste biostabilization.


Assuntos
Eliminação de Resíduos , Instalações de Eliminação de Resíduos , Anaerobiose , Reatores Biológicos
7.
Bioresour Technol ; 128: 351-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23201514

RESUMO

The aim of this work was to evaluate the effects of short full scale MBT process (28 d) getting a biological stability of DRI < 1000 mg O(2) kg VS(-1) h(-1), on the impact of leachate produced in simulated landfill. As consequence of that, waste was processed by full scale MBT and both untreated and treated waste were successively incubated in simulated landfills for 1 year. Leachates were collected at different incubation times and characterized. Results obtained indicated that MBT allowed waste-organic matter (OM) reduction favoring, also, optimal condition for successive OM degradation in the simulated landfill. Final results indicated a total reduction of leachate impact for the treated waste (DRI of 978 mg O(2)kg VS(-1) h(-1)) with respect to the untreated waste of: -54%, -69%, -77%, -70%, -81% and -16% for NTK, NH(3), TOC, COD, BOD(5) and total heavy metal contents, respectively.


Assuntos
Análise da Demanda Biológica de Oxigênio/métodos , Meio Ambiente , Eliminação de Resíduos/métodos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Estresse Mecânico
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