ESTRUCTURA DE LA VEGETACIÓN EN MONTÍCULOS DE LA BAHÍA DE LA PAZ, BAJA CALIFORNIA SUR, MÉXICO

Abstract

Sarcocaulescent scrub is the dominant vegetation of the Baja California Peninsula. The
microtopography of the alluvial plains in
the lower sector of Bahia de La Paz area is
characterized by patches of soil mounds that
accommodate characteristic plant species,
the most dominant of which are shrubby,
such as Jatropha cuneata, J. cinerea, Stenocereus gummosus, Bursera microphylla,
Fouquieria diguetii, Caesalpinia placida,
and Larrea divaricata. We performed tests
of independence (χ2 chi-square) between
pairs of species to analyze relationships in
the grouping of the dominant plant species
on the soil mounds. Results show scarce
positive interactions that behave consistently between the species, suggesting random
clustering of the sampled species. Soil
analysis of the mounds and the neighboring
bare zones shows differences in salinity
and organic matter content, which implies
better nutrient conditions on the mounds.
The micro-environmental conditions of the
mounds identify them as resource islands
that participate actively in the structure and
dynamics of vegetation desert communities
as here refered.