Covariance of oxygen and hydrogen isotopic composition in plant water: Species effects

Journal Article · Fri Dec 01 00:00:00 EST 1989 · Ecology; (United States)

DOI:https://doi.org/10.2307/1938095· OSTI ID:5742147

Cooper, L W; DeNiro, M J ^[1]

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1. Univ. of California, Los Angeles (United States)

Leaf water becomes enriched in the heavy isotopes of oxygen and hydrogen during evapotranspiration. The magnitude of the enrichment has been shown to be influenced by temperature and humidity, but the effects of species-specific factors on leaf water enrichment of D and {sup 18}O have not been studied for different plants growing together. To learn whether leaf water enrichment patterns and processes for D and {sup 18}O are different for individual species growing under the same environmental conditions the authors tested the proposal that leaf waters in plants with crassulacean acid metabolism (CAM) show high sloped (m in the leaf water equation {delta}D = m {delta}{sup 18}O + b) than in C{sub 3} plants. They determined the relationships between the stable hydrogen ({delta}D) and oxygen ({delta}{sup 18}O) isotope ratios of leaf waters collected during the diurnal cycle of evapotranspiration for Yucca schidigera, Ephedra aspera, Agave deserti, Prunus ilicifolia, Yucca whipplei, Heteromeles arbutifolia, Dyckia fosteriana, Simmondsia chinensis, and Encelia farinosa growing at two sites in southern California. The findings indicate that m in the aforementioned equation is related to the overall residence time for water in the leaf and proportions of water subjected to repeated evapotranspiration enrichments of heavy isotopes.

• OSTI ID: 5742147
• Journal Information: Ecology; (United States), Vol. 70:6; ISSN 0012-9658
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
PLANTS
ISOTOPE RATIO
ABUNDANCE
DAILY VARIATIONS
DESERTS
DEUTERIUM
EVAPORATION
GENETIC VARIABILITY
HUMIDITY
LEAVES
OXYGEN 18
STABLE ISOTOPES
TEMPERATURE DEPENDENCE
TRANSPIRATION
ARID LANDS
BIOLOGICAL VARIABILITY
EVEN-EVEN NUCLEI
HYDROGEN ISOTOPES
ISOTOPES
LIGHT NUCLEI
NUCLEI
ODD-ODD NUCLEI
OXYGEN ISOTOPES
PHASE TRANSFORMATIONS
VARIATIONS
551001* - Physiological Systems- Tracer Techniques