Effects of chronic warming and nutrient additions on ecosystem respiration and methane fluxes along a tundra moisture gradient

Conference · Wed Jun 01 04:00:00 EDT 1994 · Bulletin of the Ecological Society of America; (United States)

OSTI ID:7161892

Nadelhoffer, K; Murray, G; Giblin, A; Shaver, G; Laundre, J; Johnson, L; Stanley, A ^[1]; Schimel, J ^[2]

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1. Marine Biological Laboratory, Woods Hole, MA (United States)
2. Univ. of Alaska, Fairbanks, AK (United States)

We measured ecosystem respiration (ER: or CO[sub 2] flux), methane (CH[sub 4]) fluxes and net ecosystem production (NEP) near Toolik Lake, Alaska to compare effects of temperature, moisture and nutrients on tundra C balances. We measured fluxes using closed chambers in control, warmed and fertilized plots in wet, moist and dry tundra. ER rankings of tundra types differed between years. In 1992 ER was [approximately]70 g C m[sup [minus]2]y[sup [minus]1] in wet and moist tundra and was 50% lower in dry tundra. In 1993 ER was >150 g C m[sup [minus]2]y[sup [minus]1] in moist tundra and [approximately]55 g C m[sup [minus]2]y[sup [minus]1] in wet and dry tundra. CH[sub 4] emissions ranged from 3.5 to 7 g C m[sup [minus]2]y[sup [minus]1] in wet and from 0.6 to 2.8 g C m[sup [minus]2]y[sup [minus]1] in moist tundra. Dry tundra consumed about 0.1 g CH[sub 4]-C m[sup [minus]2]y[sup [minus]1]. In wet tundra ER increased slightly with warming but dramatically with fertilization. Wet tundra NEP increased with fertilization but not with warming. CH[sub 4] emissions from wet tundra increased with warming but decreased with fertilization. Warming and fertilization increased ER but neither treatment affected NEP in moist tundra. CH[sub 4] emissions from moist tundra responded similarly but less dramatically to treatments than did wet tundra CH[sub 4] fluxes. Warming did not affect ER or NEP in dry tundra, fertilization increased both process. Consumption of CH[sub 4] in dry tundra increased with warming but decreased with fertilization.

• OSTI ID: 7161892
• Report Number(s): CONF-940894--
• Conference Information: Journal Name: Bulletin of the Ecological Society of America; (United States) Journal Volume: 75:2
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540120 -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
560400* -- Other Environmental Pollutant Effects
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALKANES
BIOCHEMISTRY
BIOLOGICAL EFFECTS
CHEMISTRY
CLIMATIC CHANGE
EMISSION
GREENHOUSE EFFECT
HYDROCARBONS
METHANE
ORGANIC COMPOUNDS
TUNDRA