RESUMEN
Abstract Forest fires are a natural element in many terrestrial ecosystems, in Mexico one of the main causes of loss of vegetation coverage is related to them. Nevertheless, no research has been carried out in the Tamaulipan thornscrub communities regarding post-fire regenerative strategies of plant species, therefore, is important to generate knowledge about the ecological role of fire in them. The aim of this study is to characterize the arboreal and shrub vegetation of a Tamaulipan thornscrub community in the Northeast of Mexico after a fire. To determine the composition, diversity and structure of the floral community consisting of trees and shrubs, 6 square-shaped sampling sites of 1,600 m2 were established 3 years after the fire. Margalef (DMg), Shannon-Weiner (H') and Pretzsch (A) indices were calculated to determine the richness, diversity and vertical stratification of species, respectively.23 species, 21 genera and 14 families of vascular plants were registered. The most species were Fabaceae (6) and Rhamnaceae (3) and Cordia boissieri was the specie with greater ecological weight (IVI = 20.3%). The indexes of richness and true diversity (DMg = 3.16; D = 16.44) showed high values, which suggests that the post-fire area has a good regeneration and a high species diversity. With these results we can conclude that the fire is an important agent of change in successional stages of Tamaulipan thornscrub with high values of regeneration after a surface fire.
Resumo Os incêndios florestais são um elemento natural em muitos ecossistemas terrestres, no México uma das principais causas de perda de cobertura vegetal está relacionada a eles, no entanto, nenhuma pesquisa foi realizada nas comunidades de espinheiros de Tamaulipan sobre as estratégias regenerativas pós-fogo de espécies de plantas, portanto, é importante gerar conhecimento sobre o papel ecológico do fogo neles. O objetivo deste estudo é caracterizar a vegetação arbórea e arbustiva de uma comunidade de plantas espinhosas no Tamaulipas, nordeste do México após um incêndio. Para determinar a composição, diversidade e estrutura da comunidade vegetal constituída por árvores e arbustos, seis locais de amostragem em forma de quadrado de 1.600 m2 cada um, foram estabelecidos três anos após o incêndio. Índices de Margalef (DMg), Shannon-Weiner (H') e Pretzsch (A) foram calculados para determinar a riqueza, diversidade e estratificação vertical das espécies, respectivamente. Foram registradas 23 espécies, 21 gêneros e 14 famílias de plantas vasculares. As mais ricas foram Fabaceae (6) e Rhamnaceae (3), Cordia boissieri foi a espécie com maior peso ecológico (IVI = 20,3%). Os índices de riqueza e diversidade verdadeira (DMg = 3,16; D = 16,44) apresentaram valores elevados, o que sugere que a área pós-fogo apresenta boa regeneração e alta diversidade Vegetal. Com estes resultados podemos concluir que o fogo é um importante agente de mudança nos estágios sucessionais do espinho de Tamaulipan com altos valores de regeneração após um incêndio na superfície.
Asunto(s)
Humanos , Ecosistema , Incendios , Plantas , Árboles , Biodiversidad , MéxicoRESUMEN
Forest fires are a natural element in many terrestrial ecosystems, in Mexico one of the main causes of loss of vegetation coverage is related to them. Nevertheless, no research has been carried out in the Tamaulipan thornscrub communities regarding post-fire regenerative strategies of plant species, therefore, is important to generate knowledge about the ecological role of fire in them. The aim of this study is to characterize the arboreal and shrub vegetation of a Tamaulipan thornscrub community in the Northeast of Mexico after a fire. To determine the composition, diversity and structure of the floral community consisting of trees and shrubs, 6 square-shaped sampling sites of 1,600 m2 were established 3 years after the fire. Margalef (DMg), Shannon-Weiner (H') and Pretzsch (A) indices were calculated to determine the richness, diversity and vertical stratification of species, respectively.23 species, 21 genera and 14 families of vascular plants were registered. The most species were Fabaceae (6) and Rhamnaceae (3) and Cordia boissieri was the specie with greater ecological weight (IVI = 20.3%). The indexes of richness and true diversity (DMg = 3.16; D = 16.44) showed high values, which suggests that the post-fire area has a good regeneration and a high species diversity. With these results we can conclude that the fire is an important agent of change in successional stages of Tamaulipan thornscrub with high values of regeneration after a surface fire.
Asunto(s)
Ecosistema , Incendios , Biodiversidad , Humanos , México , Plantas , ÁrbolesRESUMEN
Abstract Forest fires are a natural element in many terrestrial ecosystems, in Mexico one of the main causes of loss of vegetation coverage is related to them. Nevertheless, no research has been carried out in the Tamaulipan thornscrub communities regarding post-fire regenerative strategies of plant species, therefore, is important to generate knowledge about the ecological role of fire in them. The aim of this study is to characterize the arboreal and shrub vegetation of a Tamaulipan thornscrub community in the Northeast of Mexico after a fire. To determine the composition, diversity and structure of the floral community consisting of trees and shrubs, 6 square-shaped sampling sites of 1,600 m2 were established 3 years after the fire. Margalef (DMg), Shannon-Weiner (H) and Pretzsch (A) indices were calculated to determine the richness, diversity and vertical stratification of species, respectively.23 species, 21 genera and 14 families of vascular plants were registered. The most species were Fabaceae (6) and Rhamnaceae (3) and Cordia boissieri was the specie with greater ecological weight (IVI = 20.3%). The indexes of richness and true diversity (DMg = 3.16; D = 16.44) showed high values, which suggests that the post-fire area has a good regeneration and a high species diversity. With these results we can conclude that the fire is an important agent of change in successional stages of Tamaulipan thornscrub with high values of regeneration after a surface fire.
Resumo Os incêndios florestais são um elemento natural em muitos ecossistemas terrestres, no México uma das principais causas de perda de cobertura vegetal está relacionada a eles, no entanto, nenhuma pesquisa foi realizada nas comunidades de espinheiros de Tamaulipan sobre as estratégias regenerativas pós-fogo de espécies de plantas, portanto, é importante gerar conhecimento sobre o papel ecológico do fogo neles. O objetivo deste estudo é caracterizar a vegetação arbórea e arbustiva de uma comunidade de plantas espinhosas no Tamaulipas, nordeste do México após um incêndio. Para determinar a composição, diversidade e estrutura da comunidade vegetal constituída por árvores e arbustos, seis locais de amostragem em forma de quadrado de 1.600 m2 cada um, foram estabelecidos três anos após o incêndio. Índices de Margalef (DMg), Shannon-Weiner (H) e Pretzsch (A) foram calculados para determinar a riqueza, diversidade e estratificação vertical das espécies, respectivamente. Foram registradas 23 espécies, 21 gêneros e 14 famílias de plantas vasculares. As mais ricas foram Fabaceae (6) e Rhamnaceae (3), Cordia boissieri foi a espécie com maior peso ecológico (IVI = 20,3%). Os índices de riqueza e diversidade verdadeira (DMg = 3,16; D = 16,44) apresentaram valores elevados, o que sugere que a área pós-fogo apresenta boa regeneração e alta diversidade Vegetal. Com estes resultados podemos concluir que o fogo é um importante agente de mudança nos estágios sucessionais do espinho de Tamaulipan com altos valores de regeneração após um incêndio na superfície.
RESUMEN
Iron deficiency, often associated to anaemia, is the main cause of deferring women from blood donation: an incidence of 9.5% over a series of 1,437 women was found in our region. The strategy designed to face this problem was based upon precise diagnosis (erythrocyte protoporphyrin values) dietetic counselling, occasional iron therapy, and reduction of the frequency of blood donations. The results attained were encouraging, as the incidence of deferments was 13%; however, the percentage of women who quit blood donation was 86% of the first-time female donors.
Asunto(s)
Anemia Hipocrómica/prevención & control , Donantes de Sangre , Deficiencias de Hierro , Anemia/epidemiología , Anemia Hipocrómica/epidemiología , Anemia Hipocrómica/terapia , Donantes de Sangre/psicología , Estudios de Cohortes , Terapia Combinada , Femenino , Hemoglobinas/análisis , Humanos , Protoporfirinas/sangre , España/epidemiologíaRESUMEN
The incidence of anti-HCV antibodies found in 1,918 blood donors from Cantabria was 0.31%. Taking a level of 80 U/L ALT as a standpoint, 0.21% of samples with lower values correspond to anti-HCV positive cases, versus 6.25% of samples above that figure. Within those donors with ALT greater than 80 U/L, viral and non-viral profiles were established from biochemical criteria, their anti-VHC positivity frequencies being 22.22% and 0%, respectively. Non-viral profile donors represent 1% of the total number who might not be rejected.
Asunto(s)
Alanina Transaminasa/sangre , Biomarcadores/sangre , Donantes de Sangre , Anticuerpos Antihepatitis/análisis , Hepatitis C/epidemiología , Hepatitis Viral Humana/epidemiología , Estudios Transversales , Hepatitis C/inmunología , Hepatitis C/prevención & control , Hepatitis C/transmisión , Humanos , España/epidemiología , Reacción a la TransfusiónRESUMEN
Food consumption patterns have suffered important although not generalized changes in recent years. A series of factors favor these changes, such as variations in family income, rural-urban migration, increase of tertiary activities related to foods, and exposure to commercial propaganda. All of these factors, when compared among them, do not have the same impact or validity. Thus, while the first two induce changes in the food pattern, the last two guide the consumer to certain food products. Modernization of the food pattern in Latin America and the Caribbean has been inspired by the USA food pattern of the previous decade, which from the nutritional and economic points of view, does not prove to be desirable. The average USA diet is rich in both saturated and mono- and polyunsaturated fats, as well as in refined sugar and all types of additives. It is poor in carbohydrates, particular in those of the complex type; most of its protein is of animal origin. It may also be rich in salt and poor in fiber, as it is made up by well-diversified industrialized foods in their presentation, manufactured and marketed by a highly industrialized production-distribution capitalized structure. The adopted model is not in correspondence with out countries' natural resources; it produces a displacement of the consumption patterns based on autochthonous and/or traditional components, and induces an increase in food imports. Since Latin American countries are of poor economic resources, and the model renders expensive products, these are absorbed by the socioeconomic group able to pay for them and/or--intermittently--as a high-cost product by calorie delivered, by the poor groups who are most in need, a situation which would imply serious damage on the quality and quantity of their diet. Changes in food habits and in food consumption patterns are related to a certain socio-demographic process which cannot be stopped. Consequently, this process should be carefully analyzed and understood in order to contribute to channel it in the best possible manner and to protect the food and nutritional situation of the consumer. The expert in nutrition should therefore play an important role in those tasks of public benefit, fundamentally in the areas of regulation and normalization of the quality of new foods, as well as in the diffusion of information and education, at all levels, of the consumer.