Effects of bark beetle outbreaks on species composition, biomass, and nutrient distribution in a mixed deciduous forest

Conference · Thu Jan 01 04:00:00 EST 1987

OSTI ID:7190880

Johnson, D W; Henderson, G S; Harris, W F

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
• Country of Publication: United States
• Language: English

Related Subjects

510100* -- Environment
Terrestrial-- Basic Studies-- (-1989)
54 ENVIRONMENTAL SCIENCES
ANIMALS
ARTHROPODS
BIOMASS
ENERGY SOURCES
ENVIRONMENTAL EFFECTS
FORESTS
INSECTS
INVERTEBRATES
MINERAL CYCLING
MORTALITY
NATIONAL ORGANIZATIONS
NUTRIENTS
OAK RIDGE RESERVATION
PLANTS
RENEWABLE ENERGY SOURCES
SPECIES DIVERSITY
TREES
US DOE
US ERDA
US ORGANIZATIONS