Article

Estructura, composición y diversidad de la selva baja caducifolia del Cerro Verde, Nizanda (Oaxaca), México

Boletín de la Sociedad Botánica de México (Impact Factor: 0.8). 01/2005; 76.
Source: DOAJ

ABSTRACT

En este estudio se describe la estructura, la composición florística y los patrones de diversidad de la selva baja caducifolia del Cerro Verde, localizado en Nizanda (Istmo de Tehuantepec, Oaxaca, México). En 30 parcelas de 100 m2 se censaron las plantas leñosas con DAP ≥ 1 cm (estrato alto), y en cinco subcuadros de 4 m2 dentro de cada una se censaron las plantas con DAP < 1 cm, pero con altura > 30 cm (estrato bajo). Se encontraron 194 especies distribuidas en 52 familias. La riqueza de especies fue idéntica en ambos estratos (145 especies), y cada uno aportó de manera exclusiva ca. 25% de la riqueza total registrada. Leguminosae fue la familia más rica en especies (27), seguida por Asteraceae (20) y Euphorbiaceae (18). Las especies más frecuentes fueron Bursera simaruba + B. aff. cinerea (no distinguidas en el campo), Euphorbia schlechtendalii, Pilosocereus collinsii y Capparis verrucosa. La riqueza específica promedio por cuadro fue de 30 especies. Los índices basados en la riqueza y la abundancia de las especies (Berger-Parker = 0.20; Simpson = 0.09; α de Fisher = 9.47; Shannon = 2.78; equitatividad = 0.82) indican una alta diversidad y una consecuente baja dominancia en esta selva. Los valores extrapolados mostraron una densidad total (estratos alto + bajo) de 23,950 ind. ha-1 (830 ind. ha-1 con DAP ≥ 10 cm), una cobertura de 446.7%, y un área basal de 53 m2 ha-1. La altura promedio del 10% de los árboles más altos fue 9.1 m. La estructura de la selva baja del Cerro Verde es semejante a la de otras comunidades vegetales del trópico seco de México y denota un buen estado de conservación. Este hecho, aunado a su particular composición florística, enfatiza la pertinencia de su conservación formal.

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Available from: Jorge A. Meave, Aug 01, 2014
    • "En Mena Nizanda se reconocen 7 tipos de vegetación, con predominio de selva baja caducifolia, selva mediana subperennifolia, bosque de galería y vegetación secundaria (Pérez-García et al., 2001). La temperatura media anual es de 25º C, la temporada seca va de noviembre a abril y la lluviosa de mayo a octubre (García, 1988; Pérez-García et al., 2001; Gallardo-Cruz et al., 2005). La captura de los ejemplares se realizó con 3 redes de niebla de 6 ×2.5 m que se colocaron al atardecer y se retiraron al amanecer o en ausencia total de actividad de murciélagos (i. "
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    • "Location of the study site in Oaxaca state, southern Mexico to the preparation of the regional floristic inventory, vegetation was sampled in 188 100-m 2 plots surveyed in different vegetation types; although minor sampling variants existed among them (Lebrija-Trejos 2001; Pérez-García and Meave 2004; Gallardo-Cruz et al. 2005; Sierra-Huelsz 2005), presence-absence data are comparable. For comparative purposes, we constructed a single database for all species recorded in the sampling. "
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    • "At the highest zones of Mt. Cerro Verde slopes are steep and soils very shallow, all of which considerably limits plant growth (Gallardo-Cruz et al. 2005). Moreover, wind turbulence typical of the upper reaches of the mountains (Huggett 1995; Beniston 2000), which on this mountain is particularly strong due to the high speed of the Trade Winds in this region (Romero-Centeno et al. 2003), may cause significant reductions in plant cover due to the shear force of the wind (Grace 1981). "
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