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1.
Ecol Appl ; 28(8): 1982-1997, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29791763

RESUMEN

Forest fragmentation can lead to habitat reduction, edge increase, and exposure to disturbances. A key emerging policy to protect forests is payments for ecosystem services (PES), which offers compensation to landowners for environmental stewardship. Mexico was one of the first countries to implement a broad-scale PES program, enrolling over 2.3 Mha by 2010. However, Mexico's PES did not completely eliminate deforestation in enrolled parcels and could have increased incentives to hide deforestation in ways that increased fragmentation. We studied whether Mexican forests enrolled in the PES program had less forest fragmentation than those not enrolled, and whether the PES effects varied among forest types, among socioeconomic zones, or compared to the protected areas system. We analyzed forest cover maps from 2000 to 2012 to calculate forest fragmentation. We summarized fragmentation for different forest types and in four socioeconomic zones. We then used matching analysis to investigate the possible causal impacts of the PES on forests across Mexico and compared the effects of the PES program with that of protected areas. We found that the area covered by forest in Mexico decreased by 3.4% from 2000 to 2012, but there was 9.3% less forest core area. Change in forest cover was highest in the southern part of Mexico, and high-stature evergreen tropical forest lost the most core areas (-17%), while oak forest lost the least (-2%). Our matching analysis found that the PES program reduced both forest cover loss and forest fragmentation. Low-PES areas increased twice as much of the number of forest patches, forest edge, forest islets, and largest area of forest lost compared to high-PES areas. Compared to the protected areas system in Mexico, high-PES areas performed similarly in preventing fragmentation, but not as well as biosphere reserve core zones. We conclude that the PES was successful in slowing forest fragmentation at the regional and country level. However, the program could be improved by targeting areas where forest changes are more frequent, especially in southern Mexico. Fragmentation analyses should be implemented in other areas to monitor the outcomes of protection programs such as REDD+ and PES.


Asunto(s)
Conservación de los Recursos Naturales/economía , Agricultura Forestal/economía , Bosques , Biodiversidad , Conservación de los Recursos Naturales/métodos , Agricultura Forestal/métodos , México
2.
Conserv Biol ; 28(5): 1151-9, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25039240

RESUMEN

Natural resource managers are often expected to achieve both environmental protection and economic development even when there are fundamental trade-offs between these goals. Adaptive management provides a theoretical structure for program administrators to balance social priorities in the presence of trade-offs and to improve conservation targeting. We used the case of Mexico's federal Payments for Hydrological Services program (PSAH) to illustrate the importance of adaptive management for improving program targeting. We documented adaptive elements of PSAH and corresponding changes in program eligibility and selection criteria. To evaluate whether these changes resulted in enrollment of lands of high environmental and social priority, we compared the environmental and social characteristics of the areas enrolled in the program with the characteristics of all forested areas in Mexico, all areas eligible for the program, and all areas submitted for application to the program. The program successfully enrolled areas of both high ecological and social priority, and over time, adaptive changes in the program's criteria for eligibility and selection led to increased enrollment of land scoring high on both dimensions. Three factors facilitated adaptive management in Mexico and are likely to be generally important for conservation managers: a supportive political environment, including financial backing and encouragement to experiment from the federal government; availability of relatively good social and environmental data; and active participation in the review process by stakeholders and outside evaluators.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Ciclo Hidrológico , Conservación de los Recursos Naturales/economía , México
3.
Sci Total Environ ; 665: 1053-1063, 2019 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-30893737

RESUMEN

The benefits nature provides to people, called ecosystem services, are increasingly recognized and accounted for in assessments of infrastructure development, agricultural management, conservation prioritization, and sustainable sourcing. These assessments are often limited by data, however, a gap with tremendous potential to be filled through Earth observations (EO), which produce a variety of data across spatial and temporal extents and resolutions. Despite widespread recognition of this potential, in practice few ecosystem service studies use EO. Here, we identify challenges and opportunities to using EO in ecosystem service modeling and assessment. Some challenges are technical, related to data awareness, processing, and access. These challenges require systematic investment in model platforms and data management. Other challenges are more conceptual but still systemic; they are byproducts of the structure of existing ecosystem service models and addressing them requires scientific investment in solutions and tools applicable to a wide range of models and approaches. We also highlight new ways in which EO can be leveraged for ecosystem service assessments, identifying promising new areas of research. More widespread use of EO for ecosystem service assessment will only be achieved if all of these types of challenges are addressed. This will require non-traditional funding and partnering opportunities from private and public agencies to promote data exploration, sharing, and archiving. Investing in this integration will be reflected in better and more accurate ecosystem service assessments worldwide.

4.
Rev. cuba. hig. epidemiol ; 50(2): 231-244, Mayo-ago. 2012.
Artículo en Español | LILACS | ID: lil-654519

RESUMEN

Objetivo: teniendo en cuenta el riesgo potencial que para Cuba constituye la presencia del agente trasmisor, los autores consideran importante la revisión del tema con vistas a una actualización de los especialistas y demás entidades del sistema de salud que puedan intervenir en la vigilancia y control epidemiológico de esta enfermedad. Desarrollo: se comenta la historia de la enfermedad, la microbiología, la epizootiología y la epidemiología, así como las manifestaciones clínicas en los principales animales domésticos. Conclusiones: la borreliosis de Lyme es una nueva enfermedad infecciosa; comparte como otras borrelias y espiroquetas su afinidad por el sistema nervioso central y el sistema nervioso periférico, y se convierte en un diagnóstico de exclusión optimista en Neurología. Conocer sus vectores, su distribución geográfica y algunas de las características biológicas específicas de esta nueva especie de borrelia es de suma importancia para el médico práctico de este nuevo siglo, donde la inmunología y la biología molecular iluminan el oscuro camino de viejas y nuevas interrogantes


Objective: bearing in mind the risk posed by the presence of the vector of Lyme disease in Cuba, the authors have considered it necessary to carry out a review of the disease with the purpose of contributing updated information to specialists and health institutions involved in its surveillance and epidemiological control. Content: a discussion is presented of the history, microbiology, epizootiology and epidemiology of Lyme disease, as well as its clinical manifestations in the main domestic animal hosts. Conclusions: Lyme borreliosis is a new infectious disease. Like other borrelias and spirochetes, it has an affinity for the central nervous system and the peripheral nervous system, thus becoming a diagnosis of optimistic exclusion in neurology. Knowledge about the vectors, geographic distribution and some specific biological characteristics of this new borrelia species is crucial for practitioners of the 21st century, a time when immunology and molecular biology shed new light on old and new questions alike


Asunto(s)
Ixodes/patogenicidad , Enfermedad de Lyme
5.
Arch. méd. Camaguey ; 16(2): 229-243, mar.-abr. 2012.
Artículo en Español | LILACS | ID: lil-628130

RESUMEN

Las miotonías no-distróficas son un grupo importante de canalopatías del músculo esquelético caracterizadas por excitabilidad alterada de la membrana celular. Hoy día se reconocen muchos fenotipos clínicos distintos con un rango de severidad que oscila desde la miotonía neonatal severa con compromiso respiratorio hasta el ataque miotónico ligero que producen las Parálisis Periódicas.Objetivo: analizar y discutir la fisiopatología, cuadro clínico y criterios diagnósticos de las miotonías no distróficas menos frecuentes de la práctica clínica.Desarrollo: las mutaciones genéticas específicas en los canales de voltaje del cloruro y de sodio son la causa en la mayoría de los pacientes. Estudios recientes han permitido las correlaciones más precisas entre el genotipo, patrón electrofisiológico y fenotipo clínico. Se comenta además el criterio diagnóstico de cada canalopatía en particular.Conclusiones: a pesar de los adelantos significativos en la clínica, genética molecular y fisiopatología de estos desórdenes existen problemas importantes no resueltos, tales como la utilidad de los estudios neurofisiológicos para identificar el posible genotipo, la ausencia de una historia natural de las canalopatías actualmente, aun cuando está disponible el estudio de genética molecular, la asociación de las miotonías congénitas con los cambios miopáticos, la relación de las miopatías congénitas con las miotonías congénitas y por último la posibilidad de un tratamiento más especifico y adecuado en ausencia de ensayos clínicos farmacológicos aleatorizados que permitan en el futuro tratar y prevenir el daño de los canales iónicos


Myotonia non-dystrophica is an important group of skeletal muscle channelopathies characterized by altered excitability of cell membrane. Nowadays are recognized many different clinical phenotypes with a severity level, ranging from severe neonatal myotonia with respiratory compromise to mild myotonic attack produced by periodical paralysis. Objective: to analyze and discuss the physiopathology, clinical picture and diagnostic criteria of myotonia non-dystrophica less frequent in clinical practice.Development: the specific genetic mutations in the chloride and sodium voltage channels are the cause in the majority of patients. Recent studies have allowed more precise correlations between genotype, electrophysiologic pattern and clinical phenotype. In addition each channelopathy diagnosis criterion is discussed.Conclusions: despite significant advances in the clinic, molecular genetics and physiopathology of these disorders, there are important unresolved issues, such as the usefulness of neurophysiologic studies to identify possible genotype, the absence of a natural history on channelopathy currently, even when is available the study of molecular genetics, the association of myotonia congenita with myopathic changes, the relationship of myotonia congenita with congenital myopathies and finally the possibility of a more specific and appropriate treatment in the absence of randomized pharmacologic clinical trials to enable in the future treating and preventing ionic channels damage


Asunto(s)
Humanos , Miotonía Congénita/diagnóstico , Miotonía Congénita/terapia
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