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1.
Sci Rep ; 11(1): 20641, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34667199

RESUMO

The Iberian hare (Lepus granatensis) is an important small game species endemic to the Iberian Peninsula for which the incidence of roadkill is unknown. We surveyed Iberian hare-vehicle accidents on road networks in southern Spain, focusing on roads that mainly run through favorable habitats for this species: Mediterranean landscapes with plots of arable crops, olive groves, and vineyards. We recorded roadkills over a 5-month period, estimated hare accident densities on roads, and compared these numbers to hare hunting yields in adjoining hunting estates. We also analyzed the spatial patterns of and potential factors influencing hare roadkills. We detected the existence of black spots for hare roadkills in areas with high landscape heterogeneity that also included embankments and nearby crossroads and had high traffic intensity. Hare roadkill levels ranged from 5 to 25% of the annual harvest of hares killed on neighboring hunting estates. We suggest that road collisions should be considered in Iberian hare conservation in addition to hunting, since they may represent an additive source of mortality. Game managers should address the issue of hare roadkill in harvest planning to compensate for hare accidents, adjusting hunting quotas to account for this unnatural source of mortality. Our results suggest future directions for applied research in road ecology, including further work on demographic compensation and roadkill mitigation.

2.
Sci Rep ; 10(1): 791, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964998

RESUMO

Linear infrastructure intrusions into natural ecosystems, such as motorways and high-speed railways, causes direct loss of habitat but also impacts fauna through collisions. Wildlife road mortality is well documented and extensive conservation legislation exists in many countries to minimise the negative impact of these infrastructures. However, although these measures are implemented because of legislation, these structures are often not adequately maintained. Here we present data on the functionality of perimeter fences along two motorways in Malaga province (southern Spain) erected to prevent collisions with the common chameleon (Chamaeleo chamaeleon). We sampled the fences along the 14 km of the two motorways included in the 17 1 × 1 km squares of the study area. Our results show that the reptile fence is permeable throughout at those points where the metal sheeting was absent and where the vegetation had overgrown around the fence, hence allowing chameleons to cross. Given our results, we conclude that this situation is likely to be similar in other regions of Spain and in other countries. This is because construction/concessionary companies do not consider the environmental impact of construction projects in the medium and long term, and environmental authorities do not ensure that companies comply with the legislation.


Assuntos
Conservação dos Recursos Naturais/métodos , Lagartos , Animais , Ecossistema , Espécies em Perigo de Extinção , Espanha
3.
Sci Rep ; 7(1): 14291, 2017 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-29085050

RESUMO

Ebola virus disease (EVD) is a contagious, severe and often lethal form of hemorrhagic fever in humans. The association of EVD outbreaks with forest clearance has been suggested previously but many aspects remained uncharacterized. We used remote sensing techniques to investigate the association between deforestation in time and space, with EVD outbreaks in Central and West Africa. Favorability modeling, centered on 27 EVD outbreak sites and 280 comparable control sites, revealed that outbreaks located along the limits of the rainforest biome were significantly associated with forest losses within the previous 2 years. This association was strongest for closed forests (>83%), both intact and disturbed, of a range of tree heights (5->19 m). Our results suggest that the increased probability of an EVD outbreak occurring in a site is linked to recent deforestation events, and that preventing the loss of forests could reduce the likelihood of future outbreaks.


Assuntos
Conservação dos Recursos Naturais/estatística & dados numéricos , Surtos de Doenças/estatística & dados numéricos , Doença pelo Vírus Ebola/epidemiologia , Tecnologia de Sensoriamento Remoto , África Central/epidemiologia , África Ocidental/epidemiologia , Surtos de Doenças/prevenção & controle , Ebolavirus/isolamento & purificação , Doença pelo Vírus Ebola/prevenção & controle , Doença pelo Vírus Ebola/virologia , Atividades Humanas , Humanos , Floresta Úmida , Análise Espaço-Temporal , Árvores/fisiologia
4.
Rev. biol. trop ; 64(4): 1661-1682, oct.-dic. 2016. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-958242

RESUMO

Abstract:Remote sensing and traditional ecological knowledge (TEK) can be combined to advance conservation of remote tropical regions, e.g. Amazonia, where intensive in situ surveys are often not possible. Integrating TEK into monitoring and management of these areas allows for community participation, as well as for offering novel insights into sustainable resource use. In this study, we developed a 250 m resolution land-cover map of the Western Guyana Shield (Venezuela) based on remote sensing, and used TEK to validate its relevance for indigenous livelihoods and land uses. We first employed a hyper-temporal remotely sensed vegetation index to derive a land classification system. During a 1 300 km, eight day fluvial expedition in roadless areas in the Amazonas State (Venezuela), we visited six indigenous communities who provided geo-referenced data on hunting, fishing and farming activities. We overlaid these TEK data onto the land classification map, to link land classes with indigenous use. We characterized land classes using patterns of greenness temporal change and topo-hydrological information, and proposed 12 land-cover types, grouped into five main landscapes: 1) water bodies; 2) open lands/forest edges; 3) evergreen forests; 4) submontane semideciduous forests, and 5) cloud forests. Each land cover class was identified with a pulsating profile describing temporal changes in greenness, hence we labelled our map as "The Forest Pulse". These greenness profiles showed a slightly increasing trend, for the period 2000 to 2009, in the land classes representing grassland and scrubland, and a slightly decreasing trend in the classes representing forests. This finding is consistent with a gain in carbon in grassland as a consequence of climate warming, and also with some loss of vegetation in the forests. Thus, our classification shows potential to assess future effects of climate change on landscape. Several classes were significantly connected with agriculture, fishing, overall hunting, and more specifically the hunting of primates, Mazama americana, Dasyprocta fuliginosa, and Tayassu pecari. Our results showed that TEK-based approaches can serve as a basis for validating the livelihood relevance of landscapes in high-value conservation areas, which can form the basis for furthering the management of natural resources in these regions. Rev. Biol. Trop. 64 (4): 1661-1682. Epub 2016 December 01.


Resumen:La teledetección y el conocimiento ecológico tradicional (CET) se pueden combinar para avanzar en la conservación de regiones tropicales remotas como la Amazonía, donde la toma de datos intensiva in situ a menudo es imposible. Integrar el CET en el seguimiento y el manejo de estas áreas permite la participación de la comunidad, y ofrece nuevos puntos de vista sobre el uso sostenible de los recursos naturales. En este estudio se desarrolla un mapa de cobertura del suelo del Escudo Guayanés (Venezuela), con una resolución espacial de 250 m, basado en datos de teledetección, y se utiliza el CET para validar su relevancia en relación con la subsistencia de los pueblos indígenas y el uso que éstos hacen del territorio. En primer lugar se ha empleado un índice de vegetación basado en teledetección hiper-temporal para realizar una clasificación del territorio. Durante una expedición fluvial de 8 días, a lo largo de 1 300 km por áreas sin carreteras en el Estado Amazonas (Venezuela), se han visitado seis comunidades que han proporcionado datos geo-referenciados sobre sus actividades cinegéticas, pesqueras y agrícolas. Estos datos de CET se han superpuesto al mapa de clasificación, con el fin de relacionar las clases de coberturas con los usos indígenas. Se han caracterizado las clases de cobertura en función de patrones de cambio temporal del verdor y la topo-hidrografía, y se han propuesto 12 tipos de cobertura del suelo, agrupadas en cinco tipos principales de paisaje: 1) masas de agua; 2) campo abierto/ márgenes del bosque; 3) bosques siempre-verdes; 4) bosques semi-caducifolios submontanos; y 5) bosques nublados. Cada clase de cobertura del suelo se ha identificado con un perfil pulsátil que describe cambios temporales en el verdor, de ahí que el mapa haya sido titulado "El Pulso del Bosque". Estos perfiles de verdor han mostrado una tendencia ligeramente ascendente, durante el periodo 2000 a 2009, en las clases que representan pastizales y zonas de matorral, así como una tendencia ligeramente decreciente en las clases que representan bosques. Este hallazgo es compatible con la ganancia de carbono en los pastizales como consecuencia del calentamiento del clima, y también con una cierta pérdida de vegetación en los bosques. De este modo, nuestra clasificación muestra potencial para la evaluación de efectos futuros del cambio climático sobre el paisaje. Algunas clases han resultado estar significativamente relacionadas con la agricultura, la pesca, la caza como práctica general, y más concretamente con la caza de primates, de Mazama Americana, Dasyprocta fuliginosa, y Tayassu pecari. Los resultados demuestran la utilidad de las aproximaciones basadas en CET como base para validar la importancia del paisaje, en áreas con alto valor de conservación, para la supervivencia de las personas, lo que proporciona una base para avanzar en el manejo de los recursos naturales en estas regiones.


Assuntos
Humanos , Indígenas Sul-Americanos/etnologia , Florestas , Tecnologia de Sensoriamento Remoto/métodos , Mapeamento Geográfico , Análise Espaço-Temporal , Monitorização de Parâmetros Ecológicos/métodos , Valores de Referência , Venezuela/etnologia , Modelos Logísticos , Reprodutibilidade dos Testes , Conservação dos Recursos Naturais , Pradaria , Rios , Agricultura/estatística & dados numéricos
5.
PLoS One ; 11(1): e0144499, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26735953

RESUMO

Pygmy populations occupy a vast territory extending west-to-east along the central African belt from the Congo Basin to Lake Victoria. However, their numbers and actual distribution is not known precisely. Here, we undertake this task by using locational data and population sizes for an unprecedented number of known Pygmy camps and settlements (n = 654) in five of the nine countries where currently distributed. With these data we develop spatial distribution models based on the favourability function, which distinguish areas with favourable environmental conditions from those less suitable for Pygmy presence. Highly favourable areas were significantly explained by presence of tropical forests, and by lower human pressure variables. For documented Pygmy settlements, we use the relationship between observed population sizes and predicted favourability values to estimate the total Pygmy population throughout Central Africa. We estimate that around 920,000 Pygmies (over 60% in DRC) is possible within favourable forest areas in Central Africa. We argue that fragmentation of the existing Pygmy populations, alongside pressure from extractive industries and sometimes conflict with conservation areas, endanger their future. There is an urgent need to inform policies that can mitigate against future external threats to these indigenous peoples' culture and lifestyles.


Assuntos
Densidade Demográfica , África Central , Florestas , Migração Humana , Humanos , Modelos Teóricos
6.
Rev Biol Trop ; 64(4): 1661-82, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29465944

RESUMO

Remote sensing and traditional ecological knowledge (TEK) can be combined to advance conservation of remote tropical regions, e.g. Amazonia, where intensive in situ surveys are often not possible. Integrating TEK into monitoring and management of these areas allows for community participation, as well as for offering novel insights into sustainable resource use. In this study, we developed a 250 m resolution land-cover map of the Western Guyana Shield (Venezuela) based on remote sensing, and used TEK to validate its relevance for indigenous livelihoods and land uses. We first employed a hyper-temporal remotely sensed vegetation index to derive a land classification system. During a 1 300 km, eight day fluvial expedition in roadless areas in the Amazonas State (Venezuela), we visited six indigenous communities who provided geo-referenced data on hunting, fishing and farming activities. We overlaid these TEK data onto the land classification map, to link land classes with indigenous use. We characterized land classes using patterns of greenness temporal change and topo-hydrological information, and proposed 12 land-cover types, grouped into five main landscapes: 1) water bodies; 2) open lands/forest edges; 3) evergreen forests; 4) submontane semideciduous forests, and 5) cloud forests. Each land cover class was identified with a pulsating profile describing temporal changes in greenness, hence we labelled our map as "The Forest Pulse". These greenness profiles showed a slightly increasing trend, for the period 2000 to 2009, in the land classes representing grassland and scrubland, and a slightly decreasing trend in the classes representing forests. This finding is consistent with a gain in carbon in grassland as a consequence of climate warming, and also with some loss of vegetation in the forests. Thus, our classification shows potential to assess future effects of climate change on landscape. Several classes were significantly connected with agriculture, fishing, overall hunting, and more specifically the hunting of primates, Mazama americana, Dasyprocta fuliginosa, and Tayassu pecari. Our results showed that TEK-based approaches can serve as a basis for validating the livelihood relevance of landscapes in high-value conservation areas, which can form the basis for furthering the management of natural resources in these regions.


Assuntos
Monitorização de Parâmetros Ecológicos/métodos , Florestas , Mapeamento Geográfico , Indígenas Sul-Americanos/etnologia , Tecnologia de Sensoriamento Remoto/métodos , Análise Espaço-Temporal , Agricultura/estatística & dados numéricos , Conservação dos Recursos Naturais , Pradaria , Humanos , Modelos Logísticos , Valores de Referência , Reprodutibilidade dos Testes , Rios , Venezuela/etnologia
7.
Sci Rep ; 5: 8168, 2015 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-25639588

RESUMO

We studied links between human malnutrition and wild meat availability within the Rainforest Biotic Zone in central Africa. We distinguished two distinct hunted mammalian diversity distributions, one in the rainforest areas (Deep Rainforest Diversity, DRD) containing taxa of lower hunting sustainability, the other in the northern rainforest-savanna mosaic, with species of greater hunting potential (Marginal Rainforest Diversity, MRD). Wild meat availability, assessed by standing crop mammalian biomass, was greater in MRD than in DRD areas. Predicted bushmeat extraction was also higher in MRD areas. Despite this, stunting of children, a measure of human malnutrition, was greater in MRD areas. Structural equation modeling identified that, in MRD areas, mammal diversity fell away from urban areas, but proximity to these positively influenced higher stunting incidence. In DRD areas, remoteness and distance from dense human settlements and infrastructures explained lower stunting levels. Moreover, stunting was higher away from protected areas. Our results suggest that in MRD areas, forest wildlife rational use for better human nutrition is possible. By contrast, the relatively low human populations in DRD areas currently offer abundant opportunities for the continued protection of more vulnerable mammals and allow dietary needs of local populations to be met.


Assuntos
Ingestão de Alimentos , Carne , África Central , Animais , Animais Selvagens , Conservação dos Recursos Naturais , Humanos , Modelos Biológicos , Fenômenos Fisiológicos da Nutrição , Dinâmica Populacional
8.
Conserv Biol ; 29(3): 805-15, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25580729

RESUMO

We used data on number of carcasses of wildlife species sold in 79 bushmeat markets in a region of Nigeria and Cameroon to assess whether species composition of a market could be explained by anthropogenic pressures and environmental variables around each market. More than 45 mammal species from 9 orders were traded across all markets; mostly ungulates and rodents. For each market, we determined median body mass, species diversity (game diversity), and taxa that were principal contributors to the total number of carcasses for sale (game dominance). Human population density in surrounding areas was significantly and negatively related to the percentage ungulates and primates sold in markets and significantly and positively related to the proportion of rodents. The proportion of carnivores sold was higher in markets with high human population densities. Proportion of small-bodied mammals (<1 kg) sold in markets increased as human population density increased, but proportion of large-bodied mammals (>10 kg) decreased as human population density increased. We calculated an index of game depletion (GDI) for each market from the sum of the total number of carcasses traded per annum and species, weighted by the intrinsic rate of natural increase (rmax ) of each species, divided by individuals traded in a market. The GDI of a market increased as the proportion of fast-reproducing species (highest rmax ) increased and as the representation of species with lowest rmax (slow-reproducing) decreased. The best explanatory factor for a market's GDI was anthropogenic pressure-road density, human settlements with >3000 inhabitants, and nonforest vegetation. High and low GDI were significantly differentiated by human density and human settlements with >3000 inhabitants. Our results provided empirical evidence that human activity is correlated with more depleted bushmeat faunas and can be used as a proxy to determine areas in need of conservation action.


Assuntos
Conservação dos Recursos Naturais , Mamíferos , Carne , Densidade Demográfica , Animais , Camarões , Comércio , Conservação dos Recursos Naturais/economia , Humanos , Carne/economia , Nigéria
9.
Arch Orthop Trauma Surg ; 135(3): 351-6, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25556660

RESUMO

INTRODUCTION: Osteopetrosis is caused by general increase in bone density and obliteration of the medullary canal. Fractures are a frequent complication and their management is considered a challenge due to increased resistance to reaming and screw positioning; reduction maneuvers have to be done more carefully to avoid intraoperative fractures, and there is an increased risk of drill breakage. There is also a higher risk of infection and malunion, which increases the incidence of surgical revisions in this population. CASE REPORT: 55-year-old male with osteopetrosis and a history of two previous proximal femur fractures, who sustained an oblique supracondylar fracture of the left humerus and a simple, intra-articular, rotated fragment with capitelum involvement, as well as a fracture in the base of the coronoid process was admitted in our hospital. We performed an open reduction and internal fixation (ORIF) and 12 months after surgery, the patient's bone has healed and he recovered flexion (110˚) and extension (-10˚) without complications. DISCUSSION: During ORIF, two drill bits were broken and screw fixation was challenging due to the strength required. Bone overheating was also present during drilling, evidenced by smoke production and increased temperature of both bone and drill bits. Recommendations to avoid these problems include continuous cold saline irrigation, frequent drill bit changing, and spaced cycles with low-speed drilling. Additionally, high-resistance and high-speed electric drill bits can also be effective. Finally, patients should be closely followed postoperatively due to the high incidence of refracture, infection and malunion. CONCLUSIONS: Fracture fixation in patients with osteopetrosis requires strategies to overcome the technical difficulties found during the procedure. Preoperative planning must include the availability of multiple metal drill bits, electric drills, and bone substitutes, having in mind drilling techniques, drilling speed, and temperature control. Patients should be closely followed to evidence any complications such as infections and malunions.


Assuntos
Articulação do Cotovelo/cirurgia , Fixação Interna de Fraturas/métodos , Fraturas do Úmero/cirurgia , Osteopetrose/complicações , Fixação Interna de Fraturas/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Lesões no Cotovelo
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