Nayely Martínez-Meléndez

The Vascular Epiphyte Flora of El Triunfo Biosphere Reserve, Chiapas, México

Abstract An analysis of the vascular epiphytes of El Triunfo Biosphere Reserve was made based on eight years of field work and herbarium data. Four hundred and sixty five species and infraspecies of vascular epiphytes from 131 genera and 31 families are listed. Approximately 9% were found to be true epiphytes, whereas 0.65% were accidental epiphytes. Orchidaceae was the most species-rich family, although the genera Peperomia, Tillandsia, and Polypodium were the most rich in epiphytes.

Structure and Floristic Composition in a Successional Gradient in a Cloud Forest in Chiapas, Southern Mexico

Southern Mexico is well known for its high biodiversity (CONABIO, 2008). This biodiversity is a result of several factors like its geographic position, geographic diversity, and physiographic richness (Ferrusquilla-Villafranca, 1998). In particular, Chiapas, Mexicos southernmost state holds seven physiographic zones, including valleys, mountain chains, plateaus, and coastal plains (Mullerried, 1957). Most of this biological richness is to be found in the eastern moist forest, northern mountains, central plateau, and Sierra Madre (Breedlove, 1981). The Sierra Madre mountain chain harbors some of the very last patches of Cloud Forest, which is one of the most endangered ecosystems both in Mexico and at a global scale (Challenger, 1998; Toledo-Aceves et al., 2010). Fortunately, three existing biosphere reserves namely El Triunfo, La Sepultura and Volcan Tacana, aim to protect and maintain this highly threatened ecosystem. As elsewhere, natural areas compete for land with human activities such as agriculture and cattle ranching, recently, climate change has added up to the list of threats. Only at El Triunfo reserve between 1983 and 1993 were lost 8,946 ha, including 5,084 ha of Cloud Forest (March & Flamenco, 1996). As a region, the Sierra Madre de Chiapas, was between 1998 and 2005, the region that suffered the greatest impact related to climate change in the form of massive landslides. For example, more than 15,000 ha of Cloud Forest were affected in Chiapas by Hurricane Isis (Richter, 2000), while this phenomenon has also occurred in other parts of the Americas (Restrepo & Alvarez, 2006). The loss of forest cover in the upper parts of the mountain chain generates a reduction of water retention and filtering capability which results in soil loss and consequently in river sedimentation. This also has occasioned an increment of water flow volume which augments flood risk. One way to help to reduce flood risk is through the ecological restoration of forest systems in the upper basin, and subsequent recovery of the ecological services associated to forest. Hence, information on the structure of natural plant communities, including structure and floristic composition, is central to establish sound ecological restoration strategies and policies. Our research objective, was thus, to evaluate and analyze the natural successional process in a cloud forest along a successional gradient

Nuevo registro de Bdallophytum oxylepis (Malvales: Cytinaceae) para Chiapas

Se registra por primera vez la planta parasita Bdallophytum oxylepis para el estado de Chiapas. Se trata de una especie endemica a Mexico y conocida de unas pocas localidades en los estados de Jalisco, Michoacan y Oaxaca. Este registro representa una ampliacion en su distribucion y se incrementa a dos el numero de especies de Bdallophytum en Chiapas y en la region del proyecto de Flora Mesoamericana.