A5057049419- Plant Water Relations and Carbon Dynamics
- Ecology and Vegetation Dynamics Studies
- Plant and animal studies
- Plant Diversity and Evolution
- Leaf Properties and Growth Measurement
- Plant responses to elevated CO2
- Sustainability in Higher Education
- Fern and Epiphyte Biology
- Remote Sensing in Agriculture
- Forest ecology and management
- Agroforestry and silvopastoral systems
- Environmental Education and Sustainability
- Interdisciplinary Research and Collaboration
- Plant responses to water stress
- Plant Parasitism and Resistance
- Light effects on plants
- Tree-ring climate responses
- Plant Physiology and Cultivation Studies
- Service-Learning and Community Engagement
- Ethnobotanical and Medicinal Plants Studies
- Engineering Education and Curriculum Development
- Bamboo properties and applications
- Climate Change and Environmental Impact
- Sustainability and Climate Change Governance
- Tree Root and Stability Studies
Unity College
2012-2017
University of Florida
1997-2007
Boston University
2003
Smithsonian Tropical Research Institute
2003
University of Missouri–St. Louis
1989-1999
University of Pennsylvania
1986
Recent global-scale analyses indicate that climate variability affects net carbon storage but regard temperature and precipitation to be the main contributors. Seasonal interannual variation in light availability may also limit CO 2 uptake. As an experimental test of limitation by cloud cover during tropical rainy seasons unusually heavy associated with La Niña, we installed high-intensity lamps above forest canopy augment for Luehea seemannii , a tree species, cloudy periods 1999–2000....
I: Resource acquisition Photosynthesis Photosynthetic responses of tropical forest plants to contrasting light environments-- R. Chazdon, Pearcy, D. Lee, N. Fetcher CAM and C4 in the humid tropics-- E. Medina Diel patterns CO2 exchange rainforest canopy plants-- G. Zotz, K. Winter Scaling up from leaves whole canopies for photosynthetic gas exchange-- F. Meizner, Goldstein On relationship plant geometry response-- T. Herbert characteristics trees along successional gradients -- S....
The effect of leaf aging on photosynthetic capacities was examined for upper canopy leaves five tropical tree species in a seasonally dry forest Panama. These varied mean longevity between 174 and 315 d, maximum life span 304 679 d. light-saturated CO2 exchange rates produced during the primary annual flush measured at 7-8 mo age were 33-65% 1-2 with < 1 yr. negative regression slopes capacity against steeper shorter longevity. In all species, less steep than predicted by assuming linear...
In a Neotropical moist forest at Barro Colorado Island, Panama, ° 1 3 C values of CO 2 in air and leaf tissue exhibit parallel patterns variation between the floor canopy. During daytime, from sampled m 0.5 were significantly less than that 25 m. Based on mass balance equations, up to 18% above is respiration. Respired responsible for 31 37% isotope composition leaves two species herbaceous bamboo grown well—ventilated sun treatment understory. accounts 45—70% difference understory canopy...
• Ferns have radiated into the same diverse environments as spermatophytes, and done so with an independent gametophyte that is not protected by parent plant. The degree extent of desiccation tolerance (DT) in gametophytes tropical fern species was assessed to understand mechanisms allowed ferns radiate a diversity habitats. Species from several functional groups were subjected series events, including varying degrees intensity multiple cycles. Measurements chlorophyll fluorescence used...
The effect of leaf age on photosynthetic capacity, a critical parameter in the theory optimal longevity, was studied for two tropical pioneer tree species, Cecropia longipes and Urera caracasana , seasonally dry forest Panama. These species continuously produce short‐lived leaves (74 93 d, respectively) during rainy season (May–December) orthotropic branches. However, they differ production rate, maximum number per branch, light environment experienced by leaves, mass unit area, nitrogen...
1. The effects of a sudden increase in irradiance and the high leaf temperatures characteristic canopy gap environment were studied with chlorophyll fluorescence gas-exchange measurements on shade- sun-acclimated leaves Alocasia macrorrhiza. 2. Photoinhibition occurred both sun shade during 2-h simulated treatment (1900 μmol photons m −2 s −1 ) which rose to 40°C. Dissipation excess energy was more efficient leaves, showed rapid quenching fluorescence. quantum yield photosystem II as...
Factors that influence the distribution of ferns are poorly understood and likely reflect ecology both sporophyte gametophyte generation. Little study has been done on generation, especially in regard to tropical species. The goal this was examine demography light disturbance gametophytes several epiphytic, hemiepiphytic, terrestrial fern Through a series observational experimental studies, we found increased density richness were related disturbance. By contrast, had no influence,...
Summary 13 C enrichment in emerging leaves and its effect on carbon isotopic composition (δ C) of mature were investigated the neotropical pioneer tree species, Cecropia longipes Urera caracasana , Panama. Leaves all ages analysed for δ C, gas exchange, nitrogen, leaf mass per area. Low intercellular to atmospheric dioxide (CO 2 ) partial pressure (p i : p a ); high CO air, intrinsic water‐use efficiency, internal resistance, carboxylation capacity discounted as causes enrichment. might...
ABSTRACT Using optical and photosynthetic assays from a canopy access crane, we examined the performance of tropical dry forest canopies during season in Parque Metropolitano, Panama City, Panama. Photosynthetic gas exchange, chlorophyll fluorescence, three indices derived spectral reflectance (the normalized difference vegetation index, simple ratio, photochemical index) were used as indicators structural physiological components activity. Considerable interspecific variation was evident...