To date, it is not clear which are the factors that most influence tropical forest recovery from hurricanes. Increased canopy openness and increased detritus (debris) deposition are two of the most likely factors, but due to their simultaneous occurrence during a hurricane, their relative effects cannot be separated without a manipulative experiment. Hence, in the Luquillo Experimental Forest (...

To detection of suitable sampling method to study tree canopy cover in the northern Zagros forest, Baneeh region forest, Kurdistan province, and west of Iran was selected. 40 square sample plots one hectare (100×100 m) were selected and perfect inventoried. In every sample plot the position of tree, kind of species and two diameter of crown (m) were recorded. To study of canopy cover different ...

Light is the key energy input for all vegetated systems. Forest light regimes are complex, with the vertical pattern of light within canopies influenced by forest structure. Human disturbances in tropical forests impact forest structure and hence may influence the light environment and thus competitiveness of different trees. In this study, we measured vertical diffuse light profiles along a gr...

A coupled Lagrangian random walk and atmospheric turbulence model was employed to investigate the magnitude of isoprene source distribution within a mixed deciduous forest canopy undergoing defoliation. Modeled source distributions were studied to understand how the flux footprint evolved as the total amount and vertical distribution of foliage changed during the leaf senescing and abscission p...

Leaf area and its spatial distribution are key canopy parameters needed to model the radiation regime within a forest and to compute the mass and energy exchange between a forest and the atmosphere. A much larger proportion of available net radiation is received at the forest floor in open-canopy forests than in closed-canopy forests. The proportion of ecosystem water vapor exchange (lambda E) ...

This study presents a methodology for derivation of fractional canopy cover, detection of main tree species, and extraction of forest stands using logistic regression, airborne remote sensing data and field samples. In a first step, canopy height models (CHMs) are generated using medium point density LiDAR DSM and DTM and a high-quality matching DSM. Then, fractional canopy covers are calculate...

Many processes that are fundamental to tropical rainforest maintenance and regeneration take place in the forest canopy. Recently developed access techniques afford biologists nondestructive means to document and quantify canopy biota and their accompanying activities and interactions. Results from studies involving within-canopy observations and measurements of nutrient cycling, epiphyte distr...

Remotely-sensed estimates of forest biomass are usually based on various measurements of canopy height, area, volume or texture, as derived from LiDAR, radar or fine spatial resolution imagery. These measurements are then calibrated to estimates of stand biomass that are primarily based on tree stem diameters. Although humid tropical forest seasonality can have low amplitudes compared with temp...

Field studies among diverse biomes demonstrate that mass-based nitrogen concentration at leaf and canopy scales is strongly related to carbon uptake and cycling. Combined field and airborne imaging spectrometry studies demonstrate the capacity for accurate empirical estimation of forest canopy N concentration and other biochemical constituents at scales from forest stands to small landscapes. I...

Identifying historical forest disturbances is difficult, especially in selectively logged areas. LiDAR is able to measure fine-scale variations in forest structure over multiple kilometers. We use LiDAR data from ca. 16 km2 of forest in Sierra Leone, West Africa, to discriminate areas of old-growth from areas recovering from selective logging for 23 years. We examined canopy height variation an...