Elevated atmospheric CO[sub 2] and leaf litter chemistry: Changes in microbial respiration and net N mineralization

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

OSTI ID:7163393

Randlett, D L; Zak, D R; Pregitzer, K S ^[1]

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1. Univ. of Michigan, Ann Arbor, MI (United States)

Elevated atmospheric CO[sub 2] will likely influence rates of C and N cycling in terrestrial ecosystems by altering plant litter chemistry. Several studies suggest that leaf C:N increases in plants grown at twice-ambient CO[sub 2]. Because atmospheric CO[sub 2] and soil N availability can influence leaf chemistry, we reasoned that leaf litter from plants grown at elevated CO[sub 2] in N-deficient soil should slow rates of C and N cycling. To test that hypothesis, we grew Populus x euramericana cv. Eugenei with two treatments of soil N availability (low and moderate) and CO[sub 2] (350 and 700 umol mol[sup [minus]1]) in a randomized complete block design. Kinetics of microbial respiration and net N mineralization were measured for litter-amended soils during a 32-week lab incubation. Litter C:N ratio and microbial respiration were significantly affected by soil fertility, but not by CO[sub 2]. Although the addition of leaf litter caused a net immobilization of N, rates were not significantly affected by soil fertility, but not by CO[sub 2]. Although the addition of leaf litter caused a net immobilization of N, rates were not significantly different for leaves grown at ambient and elevated CO[sub 2]. As such, we found no evidence for the hypothesis that leaf litter produced at elevated atmospheric CO[sub 2] will dampen the rates of C and N cycling in soil.

• OSTI ID: 7163393
• 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
540220* -- Environment
Terrestrial-- Chemicals Monitoring & Transport-- (1990-)
560300 -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BIOCHEMISTRY
BIOLOGICAL EFFECTS
CARBON COMPOUNDS
CARBON CYCLE
CARBON DIOXIDE
CARBON OXIDES
CHALCOGENIDES
CHEMICAL REACTIONS
CHEMISTRY
DECOMPOSITION
ECOLOGICAL CONCENTRATION
ECOSYSTEMS
ENVIRONMENTAL EFFECTS
LEAVES
MATTER
MICROORGANISMS
NITROGEN CYCLE
ORGANIC MATTER
OXIDES
OXYGEN COMPOUNDS
SOILS
TERRESTRIAL ECOSYSTEMS