Aspectos ecológicos de dos cactáceas mexicanas amenazadas: implicaciones para su conservación

Abstract

Strombocactus disciformis and Turbinicarpus pseudomacrochele are two threatened species of cacti endemic to Mexico. In this study different ecological aspects of these species such as size structure, habitat occupancy, seed germination, and seedling survival were analyzed. Additionally, human activities that could affect the population persistence were also determined. Results showed that both species have size structures with low numbers of small individuals. These species grow in particular habitats and the germination of their seeds as well as seedling survival were low. They are affected by various human activities such as illegal trade of seeds and plants, cattle grazing, and extraction of materials for construction. Of these, illegal trade apparently is one of the most important threats to population persistence of these species.

The structure of nectaries in the genus Strombocactus (Cactaceae)

“…These species are distributed in a canyon system belonging to the states of Querétaro, Guanajuato, and Hidalgo (Hernández et al 2004, Sánchez-Martínez et al 2006. The species of Strombocactus have similar habitat: small rock crevices filled with fine soil, on steep slopes and vertical walls, and emerge in places with calcareous shales, preferably in areas devoid of vegetation or sparsely vegetated (Álvarez et al 2004, Arias & Sánchez-Martínez 2010.…”

Comunidades endémicas de Cactáceas en peligro de extinción. Una necesidad de conservación de los recursos naturales del distrito de Pacaycasa. Ayacucho-Perú

“…Valuable information for conducting more detailed ecological studies, or for making decisions related to these species. Such information can be used to conduct demographic studies or monitoring to quantify changes in populations over time 32 . The low growth rates of many cacti, as well as their low levels of recruitment, mean that populations usually recover demographically extremely slowly after a disturbance.…”