ISSN:
0931-1890
Keywords:
Key words Hydraulic architecture
;
Transpiration
;
Lower montane forest
;
Cloud forest
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Abstract Plant water relations of nine woody species were studied in a lower montane rain forest in Panama. These data provide a partial test of the hypothesis that hydraulic architecture of lower montane species might limit transpiration and thus leaf size or nutrient transport (as suggested by J. Cavelier and E. G. Leigh, respectively). Diurnal variation in leaf transpiration was closely correlated with changes in net radiation. Peak transpiration rates (7 × 10–5 kg s–1 m–2) were as high as peak transpiration rates from tropical lowland forests but mean daily water use [0.39 ± 0.08 (SEM) kg m–2 day–1] were mostly lower than comparable data from tropical lowland forests. Thus transpiration rates are sufficiently high for sufficiently long periods to make it unlikely that nutrient transport is limited by transpiration. Another objective of this study was a comparison of two different methods to measure hydraulic conductance (Kh = flow rate per unit pressure gradient) and leaf specific conductance of stem segments (KL = Kh/leaf area distal to the segment). The results obtained with the traditional conductivity apparatus and the high pressure flow meter method, yielded similar results in six out of seven cases.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s004680050155
