Eco-physiological studies on desert plants
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Leptadenia pyrotechnica (Forsk.) Decne. is a leafless tree growing under, adverse arid conditions in the valleys of the Eastern Desert in Egypt.
The plant cover in areas inhabited by this species is very low and amounts to only 1% in some localities. In such an open vegetation competition between roots is lacking and each root system monopolizes a huge volume of soil.
The root system of a small Leptadenia bush penetrates to a depth of 11.5 m and has a lateral extension of 10 m. The root system exploits about 850 m3 of soil. The distribution of the roots and their branching is closely related to the availability of the soil moisture in the different strata.
The available soil moisture is not uniform throughout the whole profile. Depending on the average available soil moisture at the different depths, the total available moisture in the soil volume occupied by the root system of Leptadenia bush is found to be about 23000 kg.
The annual water output by the studied bush is found to be 5700 kg. This means that the available water in the soil occupied by the root system is sufficient to supply the plant for a period of four years without replenishment by rainfall.
The present study shows that the plant can live safely for several years under the severe conditions of the desert. The plant possesses some characteristics which help it to keep its water balance positive through increased absorption.
KeywordsSoil Moisture Root System Egypt Water Balance Plant Cover
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- Abdel Rahman, A.A., Batanouny, K.H.: Vegetation and root distribution in the different microhabitats in wadi Hof. Bull. Inst. du Désert d'Egypte 15, 55–66 (1964).Google Scholar
- Abdel Rahman, A.A., Batanouny, K.H.: The water output of the desert vegetation in the different microhabitats in wadi Hoff. J. Ecol. 53, 138–145 (1965).Google Scholar
- Addoms, R.M.: Enterance of water into suberized roots of trees. Plant. Physiol. 21, 109–111 (1946).Google Scholar
- Albertson, F.W.: Ecology of mixed Priarie in West Central Kansas. Ecol. Monog. 7, 481–547 (1937).Google Scholar
- Albertson, F.W., Weaver, J.E.: Injury and death on recovery of trees in Prairie climate. Ecol. Monog. 15, 393–433 (1945).Google Scholar
- Cannon, W.A.: The root habit of desert plants. Carnegie Inst. Washington Publ. 131, 1–96 (1911).Google Scholar
- Cook, C.W.: A study of the roots of Bromus inermis in relation to drought resistance. Ecol. 24, 169–181 (1943).Google Scholar
- Gardner, W.R.: Factors governing the pattern of water utilization in a plant root zone. Arid Zone Research No. 16. Water relationships in arid and semi-arid conditions. Proc. Madrid Symp. UNESCO, p. 93-97 (1962).Google Scholar
- Kassas, M., Zahran, M.A.: Studies on the ecology of the Red Sea coastal land. I. The district of Gebel Ataqa and El-Galala El-Bahariya. Bull. Soc. Géog. d'Egypte 35, 129–175 (1962).Google Scholar
- Kausch, W.: Saugkraft und Wassernachleitung im Boden als physiologische Faktoren unter besonderer Berücksichtigung des Tensiometers. Planta (Berl.) 45, 217–263 (1955).Google Scholar
- Kramer, P.J.: Absorption of water through suberized roots of trees. Plant. Physiol. 21, 37–41 (1946).Google Scholar
- Kramer, P.J.: Roots as absorbing organs. In: Encyclopedia of plant physiology, ed. by W. Ruhland, vol. III, p. 188–214. Berlin-Göttingen-Heidelberg: Springer 1956.Google Scholar
- Lemée, G.: L'économie de l'eau chez quelques Graminées vivaces du Sahara septentrional. Vegetation 5–6, 539–541 (1954).Google Scholar
- Migahid, A.M.: The drought resistance of Egyptian desert plants. Arid Zone Research No. 16. Plant-water relationships in arid and semi-arid conditions. Proc. Madrid Symp. UNESCO, p. 213–233 (1962).Google Scholar
- Migahid, A.M., Abdel Wahab, A.M., Batanouny, K.H.: Eco-physiological studies on desert plants. VII. Water relations of Leptadenia pyrotechnica (Forsk.) Decne. growing in the Egyptian desert. Oecologia (Berl.) 10, 79–91 (1972).Google Scholar
- Oppenheimer, H.R.: Adaptation to drought: Xerophytism. Arid Zone Research No. 15. Plant-water relationships in arid and semi-arid conditions. Review of Research. UNESCO, p. 105–138 (1960).Google Scholar
- Stocker, O.: Der Wasserhaushalt ägyptischer Wüsten- und Salz-Pflanzen, 200 p. Jena: Fischer 1928.Google Scholar
- Stocker, O., Kausch, W.: Bodenfeuchte und Tensiometermessung. Ber. dtsch. Wetter-Dienst. US-Zone 32, 15–18 (1952).Google Scholar
- Weaver, J.E.: The ecological relation of roots. Carnegie Inst. Washington Publ. 286 (1919).Google Scholar
- Weaver, J.E.: Classification of root system of forbs of grassland and consideration of their significance. Ecol. 39, 393–401 (1958).Google Scholar
- Zohary, M.: Plant life in Palestine, Israel and Jordan, 262 p. New York: The Roland Press Co. 1962.Google Scholar