RESUMO
La biodiversidad comprende la variabilidad de organismos y los sistemas ecológicos de los que forma parte, y constituye el sustento de la humanidad. Sin embargo, las actividades humanas han modificado a la biodiversidad en sus distintos niveles a un grado sin precedentes. Por lo cual, el objetivo de este trabajo fue analizar y describir el estado de la biodiversidad global y las cinco importantes causas de su declive: degradación y pérdida del hábitat, introducción de especies exóticas, sobreexplotación de recursos, contaminación y el cambio climático. La crisis actual se califica como la sexta extinción masiva, donde los anfibios y los corales formadores de arrecifes son los que presentan mayor riesgo de desaparecer. Debido a que para los próximos años el panorama no es el mejor, es urgente la toma acciones integrales para relentizar los procesos que dañan la integridad y funcionamiento de la diversidad biológica.
Biodiversity comprises the variability of organisms and the ecological systems of which it is part, and constitutes the livelihood of humanity. However, human activities have modified biodiversity at its various levels to an unprecedented level. Therefore, the aim of this work was to analyze and describe the state of global biodiversity and the five important causes of its decline: degradation and loss of habitat, introduction of exotic species, overexploitation of resources, pollution and climate change. The current crisis is classified as the sixth mass extinction, with amphibians and reef-building corals most at risk of disappearing. Because for the next few years the outlook is not the best, it is urgent to take concrete actions to slow down the processes that damage the integrity and functioning of biological diversity.
Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Extinção BiológicaRESUMO
Costa Ricas most populated area, the Central valley, has lost much of its natural habitat, and the little that remains has been altered to varying degrees. Yet few studies have been conducted to assess the need for conservation in this area. We present preliminary inventories of plants, butterflies, and day-flying moths of the Reserva Ecológica Leonelo Oviedo (RELO), a small Premontane Moist Forest preserve within the University of Costa Rica campus, located in the urbanized part of the valley. Butterflies are one of the best bio-indicators of a habitats health, because they are highly sensitive to environmental changes and are tightly linked to the local flora. A description of the RELOs physical features and its history is also presented with illustrations. Approximately 432 species of ca. 334 genera in 113 families of plants were identified. However, only 57 % of them represent species native to the Premontane Moist Forest of the region; the rest are either exotic or species introduced mostly from lowland. More than 200 species of butterflies in six families, including Hesperiidae, have been recorded. Rev. Biol. Trop. 57 (Suppl. 1): 31-67. Epub 2009 November 30.
Por ser el área más poblada del país, el valle Central de Costa Rica perdió su hábitat natural; lo poco que queda ha sido alterado en grados variados. Sin embargo, se han realizado algunos estudios para evaluar la necesidad de conservación en esta área. Se presentan inventarios preliminares de plantas, mariposas y polillas diurnas de la Reserva Ecológica Leonelo Oviedo (RELO); una pequeña reserva de bosque húmedo premontano en del campus de la Universidad de Costa Rica, ubicado en la parte urbanizada del valle. Las mariposas diurnas son uno de los mejores bio-indicadores de la salud del hábitat, porque son muy sensibles a los cambios del ambiente y están estrechamente ligadas a la flora local. Se presenta también una descripción de los caracteres físicos y la historia de la RELO, con ilustraciones. Se identificaron aproximadamente 432 especies de ca. 334 géneros en 113 familias de plantas. Sin embargo, solamente 57% de ellas son especies nativas del bosque húmedo premontano de la región; el resto son especies exóticas o introducidas en su mayoría desde tierras bajas. Se han registrado más de 200 especies de mariposas diurnas en seis familias, incluyendo Hesperiidae.
Assuntos
Plantas/classificação , Borboletas/classificação , Lepidópteros/classificação , Mariposas/classificação , Universidades , Costa Rica , Biodiversidade , Floresta Úmida , Controle Biológico por ConservaçãoRESUMO
We examined the association between geographic distribution, ecological traits, life history, genetic diversity, and risk of extinction in nonhuman primate species from Costa Rica. All of the current nonhuman primate species from Costa Rica are included in the study; spider monkeys (Ateles geoffroyi), howling monkeys (Alouatta palliata), capuchins (Cebus capucinus), and squirrel monkeys (Saimiri oerstedii). Geographic distribution was characterized accessing existing databases. Data on ecology and life history traits were obtained through a literature review. Genetic diversity was characterized using isozyme electrophoresis. Risk of extinction was assessed from the literature. We found that species differed in all these traits. Using these data, we conducted a Pearson correlation between risk of extinction and ecological and life history traits, and genetic variation, for widely distributed species. We found a negative association between risk of extinction and population birth and growth rates; indicating that slower reproducing species had a greater risk of extinction. We found a positive association between genetic variation and risk of extinction; i.e., species showing higher genetic variation had a greater risk of extinction. The relevance of these traits for conservation efforts is discussed.