Abstract:
The Luquillo Mountains of eastern Puerto Rico are used as a case study to evaluate possible single-or multiple-factor controls of productivity in montane forests. A review of published studies from the Luquillo Mountains revealed that canopy height, productivity, and species richness decline while stem density increases with elevation, as is typical of other montane forests. A mid-elevation floodplain palm stand with high levels of productivity provides a notable exception to this pattern. Previous basic and applied studies of productivity in the Luquillo Mountains have consistently considered the overall gradient in productivity to be important in understanding forest structure and function. Recent observational and experimental studies have determined that disturbance of all types is an important factor mediating productivity in both low-and high-elevation (cloud) forests, For example, low-elevation forest recovers more quickly :From hurricane disturbance and is more responsive to nutrient additions than is cloud forest. All of the factors proposed for limiting productivity are supported in one way or another by research in the Luquillo Mountains. What is critically lacking is both an appreciation for the way that these factors interact and experiments appropriate to evaluate multiple controls acting simultaneously.

Author Keywords:
altitudinal gradient, cloud forest, disturbance, fertilization, hurricane, Luquillo Mountains, Puerto Rico, USA, multiple controls, primary productivity, factors controlling, soil oxygen, transpiration, wind exposure

KeyWords Plus:
NUTRIENT LIMITATION, FOREST STRUCTURE, TROPICAL FOREST, CLOUD FOREST, RAIN-FORESTS, HURRICANE, DYNAMICS, TREE

Addresses:
Waide RB, Univ Puerto Rico, Inst Trop Ecosyst Studies, GPO Box 363682, San Juan, PR 00936 USA
Univ Puerto Rico, Inst Trop Ecosyst Studies, San Juan, PR 00936 USA
US Forest Serv, Int Inst Trop Forestry, USDA, Rio Piedras, PR 00928 USA

Publisher:
ECOLOGICAL SOC AMER, 2010 MASSACHUSETTS AVE, NW, STE 400, WASHINGTON, DC 20036 USA

IDS Number:
YR740

ISSN:
0012-9658