Comparative evaluation of the effects of acid precipitation, natural acid production, and harvesting on cation removal from forests

Conference · Sun Jan 01 04:00:00 EST 1984

OSTI ID:6171052

Johnson, D W

A comparison of the effects of acid deposition, natural leaching and harvesting on base cation export from forests in Maine, Tennessee, South Carolina, North Carolina, and Washington was made. Results showed that atmospheric deposition added at least 50-100% to natural leaching rates in study sites in the eastern United States, but only 1-2% in western Washington (the latter primarily due to high natural acid production). Sulfate flux accounted for 30-80% of total cation leaching in sites in the eastern United States, and only 3-12% of leaching in the Washington sites (the latter due to very high HCO/sub 3//sup -/ and NO/sub 3//sup -/ leaching rates). Nitrate leaching was negligible in all but a red alder site where net NO/sub 3//sup -/ leaching is caused by excess nitrogen fixation. Total base cation export by leaching exceeded Ca/sup 2 +/ + Mg/sup 2 +/ + K/sup +/ export due to whole-tree harvesting in all but one site (Camp Branch, Tennessee). (The export of Na/sup +/ via harvesting was assumed to be negligible compared to Ca/sup 2 +/, Mg/sup 2 +/, and K/sup +/.) Some sites showed a net Ca/sup 2 +/ or K/sup +/ accumulation from atmospheric deposition until they were subjected to whole-tree harvesting. Thus, leaching need not cause a net export of all nutrient cations even if total base cation export is accelerated by acid deposition. 4 references, 2 tables.

• Research Organization: Oak Ridge National Lab., TN (USA)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6171052
• Report Number(s): CONF-8411137-4; ON: DE85005254
• Country of Publication: United States
• Language: English

Related Subjects

500200* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
ACID RAIN
ALKALI METAL COMPOUNDS
ALKALINE EARTH METAL COMPOUNDS
ATMOSPHERIC PRECIPITATIONS
CALCIUM COMPOUNDS
CATIONS
CHARGED PARTICLES
CHEMISTRY
COMPARATIVE EVALUATIONS
DATA
DISSOLUTION
ENVIRONMENTAL EFFECTS
EXPERIMENTAL DATA
FORESTS
HARVESTING
INFORMATION
IONS
LEACHING
MAGNESIUM COMPOUNDS
NAPAP
NITRATES
NITROGEN COMPOUNDS
NUMERICAL DATA
OXYGEN COMPOUNDS
PH VALUE
POTASSIUM COMPOUNDS
RAIN
SEPARATION PROCESSES
SODIUM COMPOUNDS
SOIL CHEMISTRY
SULFATES
SULFUR COMPOUNDS