Forest succession in the Upper Rio Negro of Colombia and Venezuela
Woody vegetation from 23 forest stands along the Upper Rio Negro of Venezuela and Colombia was sampled in 1982 to examine the hypothesis that the Amazon forest has been largely undisturbed since the Pleistocene, to quantify vegetation development during different stages of succession following agricultural development, and to determine the time required for a successional stand to become a mature forest. The ubiquitousness of charcoal in the tierra firme forest indicated the presence of fire associated with extreme dry periods and human disturbances. Changes in species composition, vegetation structure, and woody biomass were studied on 19 abandoned farms and four mature forest stands. Living and dead biomass for the tress and their components was determined by regression equations developed from measurements of harvested trees. The rate of recovery of floristic composition, structure, and biomass following disturbance is relatively slow. Aboveground dead biomass remained high 14 years after the forest was disturbed by the agricultural practices. The lowest dead biomass is reached 20 years after abandonment, and the largest values are found in mature forests. Data analysis of 80-year-old stands showed that the species composition approached that of a mature forest. Approximately 140 to 200 years was required for an abandoned farm to attain the basal area and biomass values comparable to those of a mature forest. The results of this study indicate that recovery is five to seven times longer in the Upper Rio Negro than it is in other tropical areas in South America.
- Research Organization:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- DOE Contract Number:
- AC05-84OR21400
- OSTI ID:
- 7109527
- Report Number(s):
- ORNL/TM-9712; ON: DE87002330
- Resource Relation:
- Other Information: Thesis. Portions of this document are illegible in microfiche products. Original copy available until stock is exhausted. Thesis. Submitted by J.G. Saldarriaga to Univ. of Tennessee, Knoxville
- Country of Publication:
- United States
- Language:
- English
Similar Records
Biogeochemical impacts of submerging forests through large dams in the Rio Negro, Uruguay
Carbon dynamics of mature and regrowth tropical forests derived from a pantropical database (
Related Subjects
COLOMBIA
FORESTS
FARMS
LAND RECLAMATION
ECOLOGICAL SUCCESSION
VENEZUELA
ABANDONED SITES
BIOMASS
CARBON 14
ISOTOPE DATING
SPECIES DIVERSITY
TERRESTRIAL ECOSYSTEMS
AGE ESTIMATION
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CARBON ISOTOPES
DEVELOPING COUNTRIES
ECOSYSTEMS
ENERGY SOURCES
EVEN-EVEN NUCLEI
ISOTOPES
LATIN AMERICA
LIGHT NUCLEI
NUCLEI
RADIOISOTOPES
RENEWABLE ENERGY SOURCES
SOUTH AMERICA
YEARS LIVING RADIOISOTOPES
510100* - Environment
Terrestrial- Basic Studies- (-1989)