Landscapes Forest and Global Change - ESA - Escola Superior ...

J.O. López-Martínez et al. 2010. Ecological factors influencing beta diversity at two spatial scales in a tropical dry forest
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Figure 2. Ordination analysis at the local scale. (a) Detrended correspondence analysis (DCA) of the IVI
of each species at each site. (b) Canonical correspondence analysis biplot for the first and second axes
showing stand age, space, environmental, and landscape structure variables.
Table 1. Variation partitioning of woody plant species composition at the local scale.
PREDICTOR
VARIABLE
MARGINAL
VARIATION
EXPLAINED
PERCENT
VARIATION
EXPLAINED
Soil Variables 0.49 41.56
Stand age 0.07 6.34
Structure Metrics 0.08 6.94
Space 0.50 43.10
Share 0.02 2.06
Total inertia explained 1.17 100
Unknowledge 7.23
Total Inertia 8.40
3.2 Landscape scale.
Detrended correspondence analysis showed a short length gradient (2 sd) of species
composition. We found no clear pattern of species composition in relation to fragmentation
class (Fig. 3a) (. Redundancy analysis showed that landscape structure variables explained a
greater amount of variation in species composition than space (16.5% and 13.8%, respectively;
Table 2). Fragmentation class 4 was positively associated with SHEI and negatively associated
with LPI, whereas fragmentation class 1 showed the opposite pattern (Fig. 3b).
Figure 3. Ordination analysis at the local scale. (a) Principal components analysis (PCA) ordination of the
IVI of each species in each site or landscape. (b) Redundancy analysis biplot for the first and third axes
showing Shannon´s Evenness Index (SHEI) and Large Patch Index variables.
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.