We studied the ecological characteristics of 45–50-yr-old subtropical dry forest stands in Puerto Rico that were growing on sites that had been deforested and used intensively for up to 128 yr. The study took place in the Guánica Commonwealth Forest. Our objective was to assess the long-term effects of previous land use on this forest—i.e., its species composition, structure, and functioning. P...

In the current research, we present the results from a growth detection study in young forest and mature pine-dominated forest located on poor sites. Canopy height distributions were created from small-footprint airborne laser scanner data collected over 87 georeferenced field sample plots. The size of each plot was 300-400 m. The laser data were acquired in 1999 and 2001, and none of the plots...

Dead wood, in the form of coarse woody debris and standing dead wood, or snags, is an essential structural component of forest ecosystems. It plays a key role in nutrient cycling, ecosystem functions and provision of habitat for a wide variety of species. In order to manage dead wood in a temperate hardwood forest, an understanding of its availability and spatial distribution is important. This...

Leaf Area Index (leaf area per unit ground area, LAI) is a key driver of forest productivity but has never previously been measured directly at the landscape scale in tropical rain forest (TRF). We used a modular tower and stratified random sampling to harvest all foliage from forest floor to canopy top in 55 vertical transects (4.6 m(2)) across 500 ha of old growth in Costa Rica. Landscape LAI...

Photolysis of nitrous acid generates hydroxyl radicals—a key atmospheric oxidant—in the lower atmosphere. Significant concentrations of nitrous acid have been reported in the rural atmospheric boundary layer during the day, where photolysis of nitrous acid accounts for up to 42% of sunlight-induced radical production1–7. The observed concentrations of nitrous acid are thought to be sustained by...

Important Note! It is not the intention of this writer to teach researchers and others how to climb into the forest canopy. This article is intended as a means of acquainting those who may already be exploring the forest canopy with the idea that there are available techniques for climbing of which they may be unaware, or of which they may be aware but not utilizing. Those wishing to climb into...

Airborne light detection and ranging (LIDAR) measurements derived before and after Hurricanes Katrina and Wilma (2005) were used to quantify the impact of hurricanes and lightning strikes on the mangrove forest at two sites in Everglades National Park (ENP). Analysis of LIDAR measurements covering 61 and 68 ha areas of mangrove forest at the Shark River and Broad River sites showed that the pro...

M7e conipared bat activity levels in the Coaslal Plain of South Carolina atnong 5 habitat types: forested riparian areas, clearcuts, young pine plat~tations, mature pine plantations, and pine savannas. We used time-expansion I-adio-microphones and integrated detectors to simultaneously monitor bat activity at 3 heights (30, 10, 2 mj in each habitat type. Variation in vegetative clutter among sa...

The amount of conspicuous canopy dieback in all central Westland southern rata-kamahi forests east of the Alpine Fault, between 500 m altitude and treeline, was assessed and mapped from aerial photographs taken in 1984-85 and verified by aerial reconnaissance of selected areas in 1988. At least 20% of all canopy trees, predominantly southern rata (Metrosideros umbellata) and Hall's totara (Podo...