Treesearch

A field inventory of trees was conducted in March of 1997 in a logging concession at the Tapajos National Forest, south of Santarem, Para, Brazil. The inventory was conducted by the foresters and technicians of the Tropical Forest Foundation (FFT) and included all trees with diameter at breast height greater than or equal to 35 cm. Four blocks of approximately 100 ha each within the 3,200 ha concession were inventoried. Within each block, parallel trails 50 m apart were established, and the location of each tree measured was recorded to the nearest meter using an orthogonal coordinate...

Trace gas fluxes of carbon dioxide, methane, nitrous oxide, and nitric oxide were measured manually at undisturbed and logged forest sites in the Tapajos National Forest, near Santarem, Para, Brazil. Manual measurements were made approximately weekly at both the undisturbed and logged sites. Fluxes from clay and sand soils were completed at the undisturbed sites. Fluxes were measured at the deck (patio), skid trail, clearing and forest at the logged sites. Soil moisture is reported as daily average water-filled pore space (WFPS) for the undisturbed forest clay and sand soils. Data are...

In 1966 Eugene P. Odum delivered a speech before the Ecological Society of America that transformed the way ecologists looked at succession. His comparison of mature and successional systems lead ecologists to place secondary forests in an inferior position relative to mature ones to the point that today, prominent tropical biologists argue for and against the conservation value of secondary forests. Nevertheless, we live in the era of secondary forests that is rapidly giving way to a new era of novel tropical forests. Research in Puerto Rico documents the emergence of novel forests, which...

A plot established in 1943 in a subtropical wet forest at the Luquillo Experimental Forest of Puerto Rico has been assessed periodically for changes in species and size of all trees >4cm diameter. Forest dynamics on a 0.72ha plot (EV-3) at 400masl at El Verde show recovery principally from hurricanes of 1928 and 1932, timber stand improvement in 1958, and from Hurricanes Hugo and Georges in 1989 and 1998. Damage from Hurricane Hugo only temporarily slowed aboveground biomass accretion of the developing forest. Stand increases in basal area and biomass continue to be due principally to...

Environmental and past land use controls on tree species assemblages on the Commonwealth of Puerto Rico and the U.S. Virgin Islands were characterized to determine whether biophysical factors or land-use history has been more important in determining the species composition of secondary tropical forests after large-scale forest clearing for agriculture, widespread species introduction, and landscape-scale forest fragmentation. Post-deforestation, secondary forest assemblages are comprehensively described, both as broad general assemblages and island-specific variations by calculating...

Rapid deforestation in the Brazilian Amazon, caused by economic, social, and policy factors, has focused global and national attention on protecting this valuable forest resource. In response, Brazil reformed its federal forest laws in 2006, creating new regulatory, development, and incentive policy instruments and institutions. Federal forestry responsibilities are maintained within the ministry of the environment; its regulatory agency responsibilities are divided among three different branches of the agency; many powers are delegated to states and municipalities; and a new private...

Red- breasted Blackbird Sturnella militaris is extensively distributed through northern South America, Panama, Costa Rica and Trinidad6. Generally, it is considered ‘common’ throughout its range and, thus, is of Least Concern in terms of conservation and management needs3. The species is associated with open country, including moist grasslands and open agricultural areas, e.g., rice, row crops, and monocultures1, facilitating latitudinal, longitudinal1 and altitudinal expansion7.