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1.
Sci Total Environ ; 902: 166268, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37595929

RESUMEN

Climate change has led to altered fire patterns in the Mediterranean basin due to rising temperatures and greenhouse gas emissions, diminishing the resilience of forest ecosystems. To address this threat, forest management increasingly employs preventive measures like controlled burns, aiming to mitigate wildfire damage. However, understanding the impact of prescribed burns on vegetation remains crucial. Our study focuses on assessing the ecological effects of early-season prescribed burns on Macrochloa tenacissima communities within Pinus halepensis Mill forests on the Iberian Peninsula. These forests, with southeast-facing slopes and arid soils, heavily rely on alpha grass for post-fire recovery, acting as a shield against runoff and erosion. Yet, the presence of highly flammable resprouting species can lead to rapid combustible material accumulation. We evaluated parameters like coverage, floral diversity (α-diversity), aboveground plant biomass, photosynthetic activity, and chemical leaf properties of alpha grass, a year after a low-intensity controlled burn. Comparing burnt and unburnt areas revealed significant changes in α-diversity and ecophysiology of Macrochloa tenacissima due to early-season prescribed burns. These short-term shifts underscore the need for further exploration of underlying mechanisms. Our analysis also showed distinct shifts in alpha grass leaf chemical composition between the two plot types, potentially impacting post-fire recovery strategies. Although prescribed burning might not be optimal for reducing fire risk in resprouting species-dominated forests, it conserves native plants and enhances ecosystem diversity, providing valuable ecological benefits. In conclusion, our research deepens our understanding of early-season burning's repercussions on flammable vegetation dynamics and combustible material availability in semi-arid landscapes. It contributes to standardized management protocols, aiding effective forest service administration and wildfire risk reduction.


Asunto(s)
Incendios , Pinus , Incendios Forestales , Ecosistema , Poaceae , Plantas
2.
J Environ Manage ; 316: 115212, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35550959

RESUMEN

Forest fires intensify sediment transport and aggravate local and off-site consequences of soil erosion. This study evaluates the influence of post-fire measures on structural and functional sediment connectivity (SC) in five fire-affected Mediterranean catchments, which include 929 sub-catchments, by using the "aggregated index of connectivity" (AIC) at two temporal scenarios: I) immediately after the fire and before implementing post-fire practices ('Pre-man'), and II) two years after the fire ('Post-man'). The latter includes all the emergency stabilization practices, that are hillslope barriers, check-dams and afforestation. The stream system was set as the target of the computation (STR), to be representative of intense rainfall-runoff events with effective sediment delivery outside the catchments. Output normalization (AICN) allows comparing the results of the five basins between them. The sedimentological analysis is based on specific sediment yield (SSY) -measured at the check-dams installed after the fire -, and this data is used for output evaluation. Stream density and slope variables were the most influential factors on AICN-STR results at the sub-catchment scale. Post-fire hillslope treatments (barriers when built in high densities and afforestation) significantly reduced AICN-STR in comparison with untreated areas in both structural and functional approaches. Despite the presence of hillslope treatments, the higher erosive rainfall conditions resulted in higher AICN-STR values in the Post-man scenario (functional approach). A positive and good correlation was found between the measured SSY and the AICN-STR changes due to the post-fire practices and vegetation recovery, showing the good correspondence of the computation results and the real sediment dynamics of the studied catchments. Overall, AICN demonstrated to be a useful and versatile tool for post-fire management, which needs further research to optimize its applicability.


Asunto(s)
Incendios , Ríos , Ecosistema , Bosques , Humanos , Suelo
3.
Salud Publica Mex ; 35(1): 85-93, 1993.
Artículo en Español | MEDLINE | ID: mdl-8470024

RESUMEN

We describe the academic characteristics of the Master of Epidemiology Program taught at the Instituto de Medicina Tropical "Pedro Kourí", in La Habana, Cuba. We provide a description of the structure of the course along with its didactical principles, the main objectives of the different academic modules and the number and background of graduates from seven Classes. We also discuss potential work areas for graduates and short-term perspectives for their continuing education.


Asunto(s)
Educación de Postgrado , Epidemiología/educación , Academias e Institutos , Cuba , Curriculum , Educación Continua
4.
Rev Cubana Med Trop ; 43(3): 167-71, 1991.
Artículo en Español | MEDLINE | ID: mdl-9768182

RESUMEN

1,100 internationalist workers were surveyed in order to assess the factors bearing upon the proper use of antimalarial chemoprophylaxis in endemic areas of Africa. We detected difficulties concerning advisin and its quality. Most subjects did not begin chemoprophylaxis before leaving Cuba, according to the advice. It was proved that one third of them do not observe regularly this prophylactic measure.


Asunto(s)
Antimaláricos/uso terapéutico , Enfermedades Endémicas/prevención & control , Malaria/prevención & control , Cooperación del Paciente , África , Cuba , Femenino , Humanos , Masculino , Viaje
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