Canopy gradients in δ18O of organic matter as ecophysiological tool

被引:10
作者
Saurer, M [1 ]
Siegwolf, R [1 ]
Scheidegger, Y [1 ]
机构
[1] Paul Scherrer Inst, CH-5232 Villigen, Switzerland
关键词
canopy; Fagus sylvatica; grassland; natural variations; organic matter; oxygen; 18;
D O I
10.1080/10256010108033278
中图分类号
O61 [无机化学];
学科分类号
070301 ; 081704 ;
摘要
We determined vertical oxygen isotope gradients of leaf organic matter for a grassland in Switzerland and a mountain beech forest (Fagus sylvatica) in Northern Italy. A distinctly positive O-18/O-16 gradient with height above ground was found for the grassland (7.90/00 m (-) (1), p < 0.001), whereas the gradient was negative for the forest ( - 0.0770/00 m (- 1), p < 0.001). The results are consistent with microclimatic measurements, although large isotope variations between the species have to be taken into account for the grassland. A conceptual scheme is shown which relates the isotope enrichment to the canopy density, considering the effects of transpiration and canopy structure. We conclude that the analysis of the within canopy variation in delta O-18 of organic matter can be used to provide long-term. estimates of leaf water isotope composition, thus improving existing isotope methods to determine the gas-exchange between vegetation and atmosphere.
引用
收藏
页码:13 / 24
页数:12
相关论文
共 24 条
[1]   Relative humidity- and ABA-induced variation in carbon and oxygen isotope ratios of cotton leaves [J].
Barbour, MM ;
Farquhar, GD .
PLANT CELL AND ENVIRONMENT, 2000, 23 (05) :473-485
[2]   Evaluating kinetic fractionation factors used for ecologic and paleoclimatic reconstructions from oxygen and hydrogen isotope ratios in plant water and cellulose [J].
Buhay, WM ;
Edwards, TWD ;
Aravena, R .
GEOCHIMICA ET COSMOCHIMICA ACTA, 1996, 60 (12) :2209-2218
[3]  
CECATTI A, 1999, LAND USE CHANGES EUR, P260
[4]  
CERNUSCA A, 1999, LAND USE CHANGES EUR, P13
[5]   A three-dimensional synthesis study of delta O-18 in atmospheric CO2 .1. Surface fluxes [J].
Ciais, P ;
Denning, AS ;
Tans, PP ;
Berry, JA ;
Randall, DA ;
Collatz, GJ ;
Sellers, PJ ;
White, JWC ;
Trolier, M ;
Meijer, HAJ ;
Francey, RJ ;
Monfray, P ;
Heimann, M .
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 1997, 102 (D5) :5857-5872
[6]   ENRICHMENT OF H218O IN LEAVES OF TRANSPIRING PLANTS [J].
DONGMANN, G ;
NURNBERG, HW ;
FORSTEL, H ;
WAGENER, K .
RADIATION AND ENVIRONMENTAL BIOPHYSICS, 1974, 11 (01) :41-52
[7]  
Farquhar G. D., 1993, Stable isotopes and plant carbon-water relations., P47
[8]  
FARQUHAR GD, 1998, STABLE ISOTOPES INTE, P27
[9]   COMPARISON OF MODELED AND OBSERVED ENVIRONMENTAL-INFLUENCES ON THE STABLE OXYGEN AND HYDROGEN ISOTOPE COMPOSITION OF LEAF WATER IN PHASEOLUS-VULGARIS L [J].
FLANAGAN, LB ;
COMSTOCK, JP ;
EHLERINGER, JR .
PLANT PHYSIOLOGY, 1991, 96 (02) :588-596
[10]  
GEISSBUHLER P, THESIS U BERNE SWITZ