The dry forest of southern Ecuador and northern Perú (called the Tumbesian region) is
known for its high diversity, endemism, and healthy conservation state. Nevertheless, the forest
is exposed to many threats linked with human activities. To understand the effects of these
threats, which have not been appropriately assessed, we pose two questions: (a) What are the
diversity and structural situations of the forest? (b) Are anthropogenic activities affecting the
composition and structure of the forest? The assessed factors were species richness, diversity,
species similarity, abundance, and density. Forest information was obtained from 72 plots (total
area 25.92 ha) randomly placed to cover a wide range of stand densities (from 200 to 1100 m a.s.l.).
After constructing linear mixed models and selecting the most influential one, we determined the
individual influences of 12 predictors. The human pressure index (HPI) was the most negative
predictor of forest health, and annual precipitation was the most important abiotic predictor of
good health conditions. Livestock grazing did not significantly change the diversity and structure
of mature forest. The mean annual temperature and stoniness influenced only the basal area and
number of individuals, respectively. The species composition in our study area was not affected by
the HPI, but was strongly predicted by annual precipitation.
«
The dry forest of southern Ecuador and northern Perú (called the Tumbesian region) is
known for its high diversity, endemism, and healthy conservation state. Nevertheless, the forest
is exposed to many threats linked with human activities. To understand the effects of these
threats, which have not been appropriately assessed, we pose two questions: (a) What are the
diversity and structural situations of the forest? (b) Are anthropogenic activities affecting the
composition and structure of...
»