Effects of growth irradiance, nitrogen nutrition and watering regime on photosynthesis, leaf conductance and isoprene emission in leaves of Post Oak, Quercus stellata
- National Center for Atmospheric Research, Boulder, CO (United States) Texas A M Univ., College Station (United States)
Seedlings of Post Oak (Quercus stellata), the dominant woody species of oak savannas of east-central Texas, were grown outside in College Station, TX from April to November 1993. Plants were randomly placed in one cell of a 3 [times] 2 [times] 2 factorial experiment, employing 3 nitrogen fertilization (25, 100 and 225 ppm NH[sub 4]NO[sub 23]), 2 light levels (70% and 20% of full sun) and 2 watering regimes (to maintain 80-100% or 30-50% of field capacity). In November, net photosynthesis, leaf conductance and leaf isoprene emission rates at 30[degrees]C and PPFD=1000 [mu]mol m[sup [minus]2]s[sup [minus]1] were determined for two mature leaves on each of four plants from eight growth treatments and data were analyzed stastically. For plants grown under the lower watering regime, photosynthesis and isoprene emission increased with both increasing PPFD and nitrogen (effects significant at p<0.01). For plants grown at 70% full sun, effects of nitrogen treatment on photosynthesis, conductance and isoprene emission were significant (p<0.0001) while effects of watering treatment were not significant (p<0.2). Although watering treatment did not lead to significant differences between treatments, in a short-term drying experiment conducted on four plants, isoprene emissions increased through the drying period in previously well-watered plants, but decreased in previously droughted plants. Measurements were also made on two leaves to determine the effects of varying PPFD and temperature on rates of isoprene emission.
- OSTI ID:
- 7164001
- Report Number(s):
- CONF-940894-; CODEN: BECLAG
- Journal Information:
- Bulletin of the Ecological Society of America; (United States), Vol. 75:2; Conference: Annual Ecological Society of America (ESA) meeting: science and public policy, Knoxville, TN (United States), 7-11 Aug 1994; ISSN 0012-9623
- Country of Publication:
- United States
- Language:
- English
Similar Records
Water stress, temperature, and light effects on isoprene emission and photosynthesis of Kudzu leaves
Leaf surface traits and water storage retention affect photosynthetic responses to leaf surface wetness among wet tropical forest and semiarid savanna plants
Related Subjects
09 BIOMASS FUELS
ISOPRENE
EMISSION
NITROGEN
BIOLOGICAL EFFECTS
VARIATIONS
OAKS
PHOTOSYNTHESIS
SOLAR RADIATION
WATER
CHEMICAL REACTIONS
DIENES
ELEMENTS
HYDROCARBONS
HYDROGEN COMPOUNDS
MAGNOLIOPHYTA
MAGNOLIOPSIDA
NONMETALS
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
PLANTS
POLYENES
RADIATIONS
STELLAR RADIATION
SYNTHESIS
TREES
540120* - Environment
Atmospheric- Chemicals Monitoring & Transport- (1990-)
090800 - Biomass Fuels- Production- (1990-)