Effects of bark beetle outbreaks on species composition, biomass, and nutrient distribution in a mixed deciduous forest
The increment of forest biomass and nutrient content on Walker Branch Watershed, Tennessee, from 1967 to 1983 was interrupted by two bark beetle outbreaks. An outbreak of the southern pine beetle in the early 1970s and an outbreak of the hickory borer in the late 1970s, early 1980s killed a number of shortleaf pine (Pinus echinata) and hickory (Carya spp.) respectively. Yellow-poplar (Liriodendron tulipifera) growth increased over this 16-year period, especially in response to the mortality of shortleaf pine. The net result of these events was little change in total biomass but a substantial shift in species composition (from pine to yellow-poplar) in the Pine forest type over this period. No species has yet responded to the mortality of hickory. Due to the shift in species composition in the Pine type, calcium and magnesium accumulation rates in biomass increased but foliage biomass decreased over the inventory period. There was little change in foliage biomass or nutrient content in other forest types. The beetle attacks, combined with apparently natural self-thinning, caused a large increase in standing dead biomass and in nutrient return via tree fall. This increased rate of return will substantially alter forest floor nutrient content and availability, especially with regard to calcium and nitrogen.
- Research Organization:
- Oak Ridge National Lab., TN (USA); Missouri Univ., Columbia (USA). School of Forestry, Fisheries and Wildlife; National Science Foundation, Washington, DC (USA)
- DOE Contract Number:
- AC05-84OR21400
- OSTI ID:
- 7190880
- Report Number(s):
- CONF-870201-1; ON: DE86007237
- Resource Relation:
- Conference: Central hardwood forest conference, Knoxville, TN, USA, 24 Feb 1987; Other Information: Portions of this document are illegible in microfiche products
- Country of Publication:
- United States
- Language:
- English
Similar Records
Twenty-year changes in biomass and nutrient distribution in forests of Walker Branch Watershed, Tennessee
Net production relations of three tree species at Oak Ridge, Tennessee. [Liriodendron tulipifera; Quercus alba; Pinus echinata]
Related Subjects
FORESTS
SPECIES DIVERSITY
INSECTS
ENVIRONMENTAL EFFECTS
BIOMASS
MINERAL CYCLING
MORTALITY
NUTRIENTS
OAK RIDGE RESERVATION
TREES
ANIMALS
ARTHROPODS
ENERGY SOURCES
INVERTEBRATES
NATIONAL ORGANIZATIONS
PLANTS
RENEWABLE ENERGY SOURCES
US DOE
US ERDA
US ORGANIZATIONS
510100* - Environment
Terrestrial- Basic Studies- (-1989)