Species diversity, structure and dynamics of two populations of an endangered species, Magnolia dealbata (Magnoliaceae)
subject: Diversidad, Diversity, Magnolia dealbata, México, POPULATION, bosque nuboso, cloud forest, endangered species, especie en peligro de extinción, infrutescences, infrutescencia, población
description: Little is known about the ecology and demography of the genus Magnolia. Magnolia dealbata Zucc. is an endangered species endemic to Mexico. Two contrasting populations of M. dealbata (one from the grasslands and other from a secondary cloud forest) were studied. We asked the following questions: (a) Are size structure (diameter at breast height, DBH) and infrutescence production significantly different between the two populations? (b) What are the populations’ growth rates (λ) based on an initial 1987 study? (c) Are the associated species diversity indices of these M. dealbata populations significantly different? The results show no significant differences between the population size structure (p=.094); the growth rates of the populations were 0.992 in grassland and 1.053 in secondary cloud forest. The number of infrutescences produced in year 2001 and DBH relationship were significantly linear (p.01) between their slopes. The diversity indices were not significantly different (p>.05), and only 54% of the species were common to both sites. Our study suggests that both populations are relatively stable and that the management history could impact more on the species composition than on the diversity indices. Rev. Biol. Trop. 54 (3): 997-1002. Epub 2006 Sept. 29.La ecología y demografía del género Magnolia han sido poco estudiadas. Magnolia dealbata Zucc. es una especie endémica de México y es considerada en peligro de extinción. Se estudiaron dos poblaciones contrastantes de M. dealbata (una dentro de un pastizal y la otra dentro de vegetación secundaria del bosque mesófilo de montaña -bosque de niebla-). Buscamos respuestas a las siguientes preguntas: (a) ¿La estructura de tamaños y la producción de frutos de ambas poblaciones son significativamente diferentes? (b) ¿Cuáles son las tasas de crecimiento poblacional (λ), tomando como población inicial un estudio de 1987? (c) ¿Son significativamente diferentes los valores de diversidad de especies de ambas poblaciones? …
creator: Lázaro R Sánchez-Velásquez, María del Rosario Pineda-López
source: Revista de Biología Tropical
publisher: Vicerractoría Investigación
date: 2006
relation: http://www.scielo.sa.cr/scielo.php?script=sci_arttext&pid=S0034-77442006000300033
coverage: Biology (General)