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E. Tetetla-Rangel et al. 2010. Relationships among landscape structure, climate and rare woody species richness
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Relationships among landscape structure, climate and rare woody
species richness in the tropical forests of the Yucatan Peninsula,
Mexico
Erika Tetetla-Rangel * , J. Luis Hernández-Stefanoni & Juan Manuel Dupuy
Centro de Investigación Científica de Yucatán A.C. Unidad de Recursos Naturales,
Calle 43 # 130. Chuburná de Hidalgo. C.P. 97200, Mérida, Yucatán, México
Abstract
Two key concerns about the tropical forests of the Yucatan Peninsula are: the effects of land-use
and climate change on biodiversity, and the scant knowledge about rare plants species, which
are most vulnerable to these changes. We assessed the association of rare woody species
richness of tropical forests of the Yucatan Peninsula, classified in three levels of rarity (low,
medium and high), with landscape structure, climate and spatial dependence. We estimated the
number of rare species within 25km 2 landscape units, which were characterized using climate,
altitude and landscape configuration. Principal Neighbor Coordinate of Matrices (PCNM) and
regression analyses were performed to decompose variation of rare species richness into
environmental and spatial components. Space was the most important variable related to the
number of rare species in each of the three levels of rarity. These results suggest that dispersal
limitation or other environmental variables not considered drive richness of rare woody species.
Keywords: Landscape structure; rare woody plant species; spatial dependence; Tropical forest.
1. Introduction
Tropical forests of the Yucatan Peninsula have been converted to other land uses with unknown
effects on biodiversity. The floristic diversity of these ecosystems is mainly composed of rare
species –those having small populations, high habitat specificity and/or restricted distribution–
which are most vulnerable to extinction due to transformation and loss of habitat (Rabinowitz
1981).
To preserve rare plant species we need to know where they occur and what factors determine
their presence and abundance. Many factors affect the distribution of rare species, such as
historic events, climate, biotic interactions and spatial structure. Several studies have
demonstrated that environmental conditions (climatic, topographic and soil factors) constrain
the abundance or restrict the distribution range of these species. However, the factors that
determine species distribution vary depending on the way in which rarity is defined (Gaston
1994).
Several studies report a significant relationship between landscape configuration and plant
species diversity (Bascompte and Rodríguez 2001; Hernandez-Stefanoni, 2005). However, few
studies have related landscape structure and habitat heterogeneity to rare plant species, due to
difficulties involved in obtaining field information of this group of species (Luoto 2000).
* Corresponding author.
Email address: tetetla@cicy.mx
Forest Landscapes and Global Change-New Frontiers in Management, Conservation and Restoration. Proceedings of the IUFRO Landscape Ecology
Working Group International Conference, September 21-27, 2010, Bragança, Portugal. J.C. Azevedo, M. Feliciano, J. Castro & M.A. Pinto (eds.)
2010, Instituto Politécnico de Bragança, Bragança, Portugal.