Forestry-410
Physiological Ecology of Tropical Forests

Course Description

Tropical forests represent some of the most varied terrestrial ecosystems on the planet and are typically found within the 20 degrees latitude North\South of the equator for both the continental land masses and oceanic islands. Tropical forests, both native and planted, are coming under steadily increasing pressure as the growing human population demands an ever increasing utilization of the natural resources found within these ecosystems. In many regards resource partitioning and distribution within tropical forests are unique because of the environmental conditions of the global regions that support tropical forest ecosystems. Warm temperatures, abundant rainfall often seasonally distributed, and high levels of solar radiation energy input found in equatorial regions combine to produce complex nutrient cycles that function year round. Belowground rhizosphere water and nutrient cycling is particularly important in sustaining tropical forest ecosystems. Physiological ecology is an integrated discipline that strives to understand how the basic biological mechanisms and processes that contribute to individual tree growth are affected by the surrounding abiotic environment and in turn effect the surrounding microenvironment for other species. Tremendous advancements in field instrumentation now allow direct measurements of many important plant physiological processes such as photosynthesis, respiration, transpiration, sapflow, and leaf spectral properties.

The class objective is to provide the student with an understanding of how tropical forests function by using state-of-the-art field instrumentation and equipment to quantify and analyze tropical forest tree ecophysiological processes. Students will understand the relationships between the physical and biotic environments and how ecophysiology can have practical applications for ecologically sound resource management. This information is then used as a basis for examining temporal changes in ecosystem structure and dynamics and the role that forest management and human influences can play in the changes. The class is the capstone course in the Tropical Forest Certificate program at UHHilo.

Required readings for the class are drawn from a series of textbooks such as:

• "Tropical Forest Plant Ecophysiology" (S.S. Mulkey et al., 1996, Chapman&Hall);
• "Applications of Physiological Ecology to Forest Management" (Landsberg and Gower, 1997, Academic Press);
• "The Ecology of Tropical Forest Tree Seedlings" (M.D. Swaine, 1996, Unesco and the Parthenon Publishing Group);
• "Plant Physiological Ecology: Field Methods and Instrumentation" (Pearcy et al., 1989, Chapman and Hall).

Class format is 2 lectures\week (50 min/lec) and one five-hour laboratory session every two weeks. Laboratory sessions are organized to emphasize field activities such as instrument use and data collection followed by analysis and interpretation in the lab. Sites visits often include the National Science Foundation funded Second-Rotation Project, the Umikoa forest restoration project, UH Hilo CAFNRM Farm's low-elevation hardwood plantation, and the Kohala Cloud Forest Research project.