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1.
PLoS One ; 19(6): e0296751, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38923961

RESUMO

Forests play a key role in the mitigation of global warming and provide many other vital ecosystem goods and services. However, as forest continues to vanish at an alarming rate from the surface of the planet, the world desperately needs knowledge on what contributes to forest preservation and restoration. Migration, a hallmark of globalization, is widely recognized as a main driver of forest recovery and poverty alleviation. Here, we show that remittance from migrants reinforces forest recovery that would otherwise be unlikely with mere migration, realizing the additionality of payments for ecosystem services for China's largest reforestation policy, the Conversion of Cropland to Forest Program (CCFP). Guided by the framework that integrates telecoupling and coupled natural and human systems, we investigate forest-livelihood dynamics under the CCFP through the lens of rural out-migration and remittance using both satellite remote sensing imagery and household survey data in two representative sites of rural China. Results show that payments from the CCFP significantly increases the probability of sending remittance by out-migrants to their origin households. We observe substantial forest regeneration and greening surrounding households receiving remittance but forest decline and browning in proximity to households with migrants but not receiving remittance, as measured by forest coverage and the Enhanced Vegetation Index derived from space-borne remotely sensed data. The primary mechanism is that remittance reduces the reliance of households on natural capital from forests, particularly fuelwood, allowing forests near the households to recover. The shares of the estimated ecological and economic additionality induced by remittance are 2.0% (1.4%∼3.8%) and 9.7% (5.0%∼15.2%), respectively, to the baseline of the reforested areas enrolled in CCFP and the payments received by the participating households. Remittance-facilitated forest regeneration amounts to 12.7% (6.0%∼18.0%) of the total new forest gained during the 2003-2013 in China. Our results demonstrate that remittance constitutes a telecoupling mechanism between rural areas and cities over long distances, influencing the local social-ecological gains that the forest policy intended to stimulate. Thus, supporting remittance-sending migrants in cities can be an effective global warming mitigation strategy.


Assuntos
Conservação dos Recursos Naturais , Florestas , Migrantes , China , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/economia , Migrantes/estatística & dados numéricos , Humanos , Agricultura Florestal/economia , Agricultura Florestal/métodos , Ecossistema
2.
J Ecol Anthropol ; 22(1): 1-19, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34650337

RESUMO

Sahelian West Africa is a region that suffers from high population densities, frequent severe droughts, and enormous pressure on natural resources. Because of these challenges, it is the place where the term "desertification" was originally coined. Recently, however, experts have identified large zones of "greening" where the amount of vegetation exceeds what one would expect based on rainfall alone. This pattern is well documented, but its mechanisms remain poorly understood. This research employs participatory mapping linked with high-resolution satellite imagery to better understand the human role behind regional vegetation trends. Through a case study of three communities in northern Burkina Faso, this paper presents a pilot methodology for explicitly mapping perceived areas of both land degradation and rehabilitation. Combining participatory mapping exercises with standard image classification techniques allows areas of land degradation and rehabilitation to be precisely located and their extents measured for individual communities and their surrounding terroirs. Results of the spatial analysis show that the relative proportion of greening and browning varies among communities. In the case of Sakou, nearly 60 percent of its terroir is degraded. While in another, Kouka, this is 48 percent. This method also elicits perspectives of Burkinabè agro-pastoralists on the local land-use practices driving these twin environmental processes. Altogether, this case study demonstrates the analytical power of integrating ethnography and high-resolution satellite imagery to provide a bottom-up perspective on social-ecological dynamics.

3.
Ambio ; 48(3): 264-279, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30003512

RESUMO

The fast-paced conflicts in the Middle East can disrupt management and supply of water, particularly on dams and barrages along the Tigris and Euphrates rivers that have experienced threats or changes in sovereignty. Water supply is also under pressure from upstream water management, drought, and structural decline. In this research, we used a satellite-based algorithm, the normalized difference water index (NDWI), to monitor changes in the extent of surface reservoirs (1985-present). We compared the timeline of reservoir fluctuations with the timeline of events related to conflicts, droughts, and dam management. Our results show that the most sudden changes in water supply occurred during events related to conflict, but conflict was not often a cause of the greatest absolute changes to reservoir area. Though not as precise as on-the-ground information, satellite data can give insights to water supply when conflict has disrupted the flow of information or restricted on-the-ground data collection.


Assuntos
Secas , Rios , Oriente Médio , Abastecimento de Água
5.
Am Fam Physician ; 97(8): 510-516, 2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29671490

RESUMO

Running is a common form of exercise but predisposes athletes to several running-related injuries. Most running injuries are due to overuse and respond to conservative treatment. Tendinopathies in the patellar, Achilles, and hamstring tendons are common, and are primarily treated with eccentric exercise. Iliotibial band syndrome and patellofemoral pain syndrome are less common than patellar tendinopathy and are treated by strengthening exercises for the core and legs in addition to flexibility exercises. Acute hamstring strains and medial tibial stress syndrome require a period of relative rest, followed by stretching and graded return to activity. Tibial stress fractures require an extended period of relative rest, followed by a more gradual return to activity. Early mobilization improves recovery from ankle sprains, and exercise therapy and functional bracing while running for six to 12 months prevents reinjury. Plantar fasciopathy (plantar fasciitis) can be significantly improved with stretching, heel raises, and orthoses that provide arch support.


Assuntos
Traumatismos em Atletas , Terapia por Exercício/métodos , Doenças Musculares , Administração dos Cuidados ao Paciente/métodos , Corrida , Tendinopatia , Traumatismos em Atletas/epidemiologia , Traumatismos em Atletas/terapia , Transtornos Traumáticos Cumulativos/epidemiologia , Transtornos Traumáticos Cumulativos/terapia , Humanos , Doenças Musculares/classificação , Doenças Musculares/diagnóstico , Doenças Musculares/etiologia , Doenças Musculares/terapia , Aparelhos Ortopédicos , Prevalência , Avaliação de Sintomas/métodos , Tendinopatia/classificação , Tendinopatia/diagnóstico , Tendinopatia/etiologia , Tendinopatia/terapia , Resultado do Tratamento
6.
Hum Ecol Interdiscip J ; 45(1): 89-101, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31371846

RESUMO

Historically, the Sahel of West Africa has been considered synonymous with desertification. In recent decades, however, satellite images reveal patterns of enhanced vegetation termed the "greening of the Sahel." This greening is well-documented but its mechanisms remain poorly understood. The Sahel is also a region emerging from a thirty-year period of reduced rainfall in which several severe droughts occurred. As a response to droughts and land degradation, farmers have rehabilitated thousands of hectares of degraded soils by constructing low barriers of rock through widespread soil and water conservation (SWC) development projects. Remote sensing analyses suggest that these extensive soil conservation projects may explain greening in northern Burkina Faso. This study combines ethnographic fieldwork with the analysis of Geographic Information System (GIS) and remote sensing (RS) data to test whether SWC investments contribute to greening. Ethnographic data reveals a tension between the perceptions of rural producers who feel that their SWC efforts contribute to greening and those of state officials who contend that SWC has only local impacts and that the regional landscape continues to degrade. Our analysis of GIS and RS data suggest that both perspectives are valid but contingent on particular spatial and temporal scale used for analysis.

7.
Conserv Biol ; 28(6): 1584-93, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25115148

RESUMO

Conserving or restoring landscape connectivity between patches of breeding habitat is a common strategy to protect threatened species from habitat fragmentation. By managing connectivity for some species, usually charismatic vertebrates, it is often assumed that these species will serve as conservation umbrellas for other species. We tested this assumption by developing a quantitative method to measure overlap in dispersal habitat of 3 threatened species-a bird (the umbrella), a butterfly, and a frog-inhabiting the same fragmented landscape. Dispersal habitat was determined with Circuitscape, which was parameterized with movement data collected for each species. Despite differences in natural history and breeding habitat, we found substantial overlap in the spatial distributions of areas important for dispersal of this suite of taxa. However, the intuitive umbrella species (the bird) did not have the highest overlap with other species in terms of the areas that supported connectivity. Nevertheless, we contend that when there are no irreconcilable differences between the dispersal habitats of species that cohabitate on the landscape, managing for umbrella species can help conserve or restore connectivity simultaneously for multiple threatened species with different habitat requirements.


Assuntos
Distribuição Animal , Aves/fisiologia , Borboletas/fisiologia , Conservação dos Recursos Naturais/métodos , Ecossistema , Espécies em Perigo de Extinção , Ranidae/fisiologia , Animais , Florestas , Modelos Biológicos , North Carolina
8.
PLoS One ; 5(1): e8631, 2010 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-20072619

RESUMO

BACKGROUND: Vietnam is one of the countries most affected by outbreaks of H5N1 highly pathogenic avian influenza viruses. First identified in Vietnam in poultry in 2001 and in humans in 2004, the virus has since caused 111 cases and 56 deaths in humans. In 2003/2004 H5N1 outbreaks, nearly the entire poultry population of Vietnam was culled. Our earlier study (Wan et al., 2008, PLoS ONE, 3(10): e3462) demonstrated that there have been at least six independent H5N1 introductions into Vietnam and there were nine newly emerged reassortants from 2001 to 2007 in Vietnam. H5N1 viruses in Vietnam cluster distinctly around Hanoi and Ho Chi Minh City. However, the nature of the relationship between genetic divergence and geographic patterns is still unclear. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we hypothesized that genetic distances between H5N1 viruses in Vietnam are correlated with geographic distances, as the result of distinct population and environment patterns along Vietnam's long north to south longitudinal extent. Based on this hypothesis, we combined spatial statistical methods with genetic analytic techniques and explicitly used geographic space to explore genetic evolution of H5N1 highly pathogenic avian influenza viruses at the sub-national scale in Vietnam. Our dataset consisted of 125 influenza viruses (with whole genome sets) isolated in Vietnam from 2003 to 2007. Our results document the significant effect of space and time on genetic evolution and the rise of two regional centers of genetic mixing by 2007. These findings give insight into processes underlying viral evolution and suggest that genetic differentiation is associated with the distance between concentrations of human and poultry populations around Hanoi and Ho Chi Minh City. CONCLUSIONS/SIGNIFICANCE: The results show that genetic evolution of H5N1 viruses in Vietnamese domestic poultry is highly correlated with the location and spread of those viruses in geographic space. This correlation varies by scale, time, and gene, though a classic isolation by distance pattern is observed. This study is the first to characterize the geographic structure of influenza viral evolution at the sub-national scale in Vietnam and can shed light on how H5N1 HPAIVs evolve in certain geographic settings.


Assuntos
Evolução Molecular , Virus da Influenza A Subtipo H5N1/genética , Animais , Aves , Variação Genética , Geografia , Influenza Aviária/virologia , Vietnã
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