Homeier, J.; Breckle, S.W.; Günter, S.; Rollenbeck, R. & Leuschner, C. (2009): <b>Tree diversity, forest structure and productivity along altitudinal and topographical gradients in a species-rich Ecuadorian montane rainforest</b>. <i>Biotropica</i> <b>42</b>(2), 140-148.
Resource Description
Title:
Tree diversity, forest structure and productivity along altitudinal and topographical gradients in a species-rich Ecuadorian montane rainforest
FOR816dw ID:
682
Publication Date:
2009-08-03
License and Usage Rights:
Resource Owner(s):
Individual:
Jürgen Homeier
Contact:
email:
jhomeie <at> gwdg.de
Faculty of Resource Management
University of Applied Sciences and Arts (HAWK)
37077 Göttingen
Germany
Individual:
Siegmar Walter Breckle
Contact:
email:
webmaster <at> tropicalmountainforest.com
Individual:
Sven Günter
Contact:
email:
sven_gunter <at> yahoo.de
Dep. of Ecology and Ecosystem Management
Institute of Silviculture
Am Hochanger 13
Technische Universität München
85354 Freising
Germany
Individual:
Ruetger Rollenbeck
Contact:
email:
rollenbe <at> staff.uni-marburg.de
Laboratory for Climatology and Remote Sensing
Faculty of Geography
Philipps University of Marburg
Deutschhausstr. 10
35032 Marburg
Germany
We studied the spatial heterogeneity of tree diversity, and of forest structure and productivity in a highly diverse tropical mountain area in southern Ecuador with the aim of understanding the causes of the large variation in these parameters. Two major environmental gradients, elevation and topography, representing a broad range of climatic and edaphic site conditions, were analyzed. We found the highest species richness of trees in valleys <2100 m. Valleys showed highest values of basal area, leaf area index and tree basal area increment as well. Tree diversity also increased from ridges to valleys, while canopy openness decreased. Significant relationships existed between tree diversity and soil parameters (pH, total contents of Mg, K, Ca, N and P), and between diversity and the spatial variability of pH and Ca and Mg contents suggesting a dependence of tree diversity on both absolute levels and on the small-scale heterogeneity of soil nutrient availability. Tree diversity and basal area increment were positively correlated, partly because both are similarly affected by soil conditions. We conclude that the extraordinarily high tree species richness in the area is primarily caused by three factors: (1) the existence of steep altitudinal and topographic gradients in a rather limited area creating a small-scale mosaic of edaphically different habitats; (2) the intermingling of Amazonian lowland plant species, that reach their upper distribution limits, and of montane forest species; and (3) the geographical position of the study area between the humid eastern Andean slope and the dry interandean forests of South Ecuador.
Literature type specific fields:
ARTICLE
Journal:
Biotropica
Volume:
42
Issue:
2
Page Range:
140-148
Metadata Provider:
Individual:
Jürgen Homeier
Contact:
email:
jhomeie <at> gwdg.de
Faculty of Resource Management
University of Applied Sciences and Arts (HAWK)
37077 Göttingen
Germany
