Abstract
THE valuable concept of water movement through plants as a catenary process1 explicitly assumes no change of plant moisture content. While this assumption is adequate for many purposes, the quantities of water within larger plants are considerable, and variation over a period of time may be important. From Ovington's2 results for plantations in southern England, the moisture content of the aerial parts of the trees (expressed as the equivalent depth of water) averaged 3.3 in., with a maximum value of about 7 in. (47-year-old Picea abies). The needles of young Pinus sylvestris in pots well supplied with water had a variation over a 24-h period in summer amounting to 5 per cent of the saturated moisture content3. If similar fluctuations occur in larger trees in the field, these would amount to 0.05 in. of water or 1 l./tree at 2,000 trees/ha. in a total water content of the canopy of 40,000 kg/ha. When the soil moisture tension in the experiment with potted pines exceeded an atmosphere, internal drying of the leaves occurred and the lost water was not replaced during the night. Should the moisture tension of soil of the rooting zone in a plantation reach the wilting point, perhaps as much as another 0.1 in. of the canopy moisture might be lost if the leaf water deficits were similar to those for the potted trees.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
van den Honert, T. H., Disc. Faraday Soc., 3, 146 (1948).
Ovington, J. D., New Phytol., 55, 289 (1956).
Rutter, A. J., and Sands, K., New Phytol., 57, 50 (1958).
Clark, J., and Gibbs, R. D., Canad. J. Bot., 35, 219 (1957).
McDermott, J. J., Amer. J. Bot., 28, 506 (1941).
Leyton, L., and Reynolds, E. R. C., Rep. For. Res. Lond., 1962, 112 (1963).
Skau, C. M., and Swanson, R. H., J. Geophys. Res., 68, 4743 (1963).
Penman, H. L., Proc. Roy. Soc., A, 193, 120 (1948).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
REYNOLDS, E. Transpiration as related to Internal Water Content. Nature 207, 1001–1002 (1965). https://doi.org/10.1038/2071001a0
Issue Date:
DOI: https://doi.org/10.1038/2071001a0
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.