Slash and burn impacts on a Costa Rican wet forest site

Journal Article · Mon Jun 01 00:00:00 EDT 1981 · Ecology; (United States)

DOI:https://doi.org/10.2307/1937748· OSTI ID:6456605

Ewel, J; Berish, C; Brown, B; Price, N; Raich, J

Impacts of felling, mulching, and burning on budgets of C, N, S, P, K, Ca, and Mg; rates of CO/sub 2/ evolution from the soil; soil seed storage; and plant growth were evaluated. The felled tropical evergreen forest was 8 to 9 yr old, interspersed with patches of 70-yr-old forest and had a leaf area index of 6 and aboveground biomass of 5.2 kg/m/sup 2/. Harvest of the largest trees removed 18% of the S, and >10% of all other elements except N. During the 11-wk mulching and drying period, 33% of the K and 13% of the P disappeared, but losses of other elements were <6%. Burn temperatures were >620/sup 0/C in surface fuels, but soil temperatures were seldom >100/sup 0/C at 1 cm or >50/sup 0/C at 2 cm. The burn volatilized 1600 g/m/sup 2/ C, 49 g/m/sup 2/ N, and 13 g/m/sup 2/ S. Postburn wind and water erosion of ash, plus leaching, removed 34 g/m/sup 2/ N, 20 g/m/sup 2/ K, 1 g/m/sup 2/ P, 39 g/m/sup 2/ Ca, and 7 g/m/sup 2/ Mg, but insignificant amounts of C and S. After the burn and onset of the rains, 57% of the initial amount of N and 39% of the initial C still remained because of conservation of the organic-rich upper 3 cm of soil. Soil CO/sub 2/ evolution was greater from beneath the 11-wk-old slash (3.6 gC.m/sup -2/.d/sup -1/) than from beneath the forest (2.5 gC.m/sup -2/.d/sup -1/), probably because the slash conserved soil moisture better than the actively transpiring forest. After the burn both the burned field and forest soil evolved CO/sub 2/ at approx. =4.5 gC.m/sup -2/.d/sup -1/. At this rate, 154 d of decomposition and respiration would release as much C into the atmosphere as did the burn.

• Research Organization: Univ. of Florida, Gainesville
• OSTI ID: 6456605
• Journal Information: Ecology; (United States), Vol. 62:3
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
FORESTS
ENVIRONMENTAL IMPACTS
REGIONAL ANALYSIS
NUTRIENTS
ECOLOGICAL CONCENTRATION
BIOMASS
CARBON DIOXIDE
COMPARATIVE EVALUATIONS
COSTA RICA
FIRES
LEACHING
PH VALUE
PLANT GROWTH
QUANTITATIVE CHEMICAL ANALYSIS
QUANTITY RATIO
SAMPLING
SEEDS
SOILS
TABLES
TEMPERATURE EFFECTS
TERRESTRIAL ECOSYSTEMS
WIND
CARBON COMPOUNDS
CARBON OXIDES
CENTRAL AMERICA
CHALCOGENIDES
CHEMICAL ANALYSIS
DEVELOPING COUNTRIES
DISSOLUTION
ECOSYSTEMS
ENERGY SOURCES
GROWTH
LATIN AMERICA
OXIDES
OXYGEN COMPOUNDS
RENEWABLE ENERGY SOURCES
SEPARATION PROCESSES
510100* - Environment
Terrestrial- Basic Studies- (-1989)