Accession Number:

AD0614079

Title:

THE ROLE OF PHYSIOLOGY AND ENVIRONMENT IN THE DISTRIBUTION OF ARCTIC PLANTS,

Descriptive Note:

Corporate Author:

WISCONSIN UNIV MADISON DEPT OF METEOROLOGY

Personal Author(s):

Report Date:

1964-11-01

Pagination or Media Count:

74.0

Abstract:

Conclusions Physiology, environmental response, and the range of plant species in the arctic are all interrelated phenomena, no one of which can be described effectively without reference to the others. In general, the arctic environment supplies low amounts of precipitation, but correspondingly low evaporation rates are also the rule due to low temperatures. Both solar and thermal radiation supplies are low. Wind velocities are relatively high. The perennially frozen ground has an important effect, both in regard to temperature and to induced soil movement. Temperature influences are both important and complex. Conventional meteorloological data are misleading because plant temperatures and soil surface temperatures are often higher by several degrees, or even tens of degrees, than the air at the six foot level. The effects upon such physiological processes as mineral absorption, diffusion, transpiration, and so on, are significant to such an extent that arctic plants often can be shown to have developed special metabolic adaptations to low temperature. Notable among these special adaptations are the characteristics of protoplasm which renders it unusually frost hardy and permits continuation of growth or flowering in spring even after interruption of normal development by freezing. From available evidence, the respiration rate of arctic plants is higher than that of plants from warmer latitudes and environments when comparisons are made under identical temperatures and other environmental conditions. Author

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Distribution Statement:

APPROVED FOR PUBLIC RELEASE