Abstract
Two efforts by UN organizations to diagnose and map the distribution and trends of soil degradation in drylands are briefly described and compared.
Soil degradation by water is greatly accelerated under poor vegetation cover in the Tropics and Subtropics, probably for two major reasons: high rates of decomposition of organic matter and high intensities of rainfall. The consequences of soil losses and high water runoff can reach far downstream in the river basin, causing damage by sedimentation on floodplains and in reservoirs.
Damages by wind erosion and deposition are also much accelerated by overexploitation of the meagre vegetation cover of drylands. Overgrazing, overcultivation, firewood collection are the consequences of human and animal pressure, leading to more or less long-lasting desertification. The finer material, clay, silt, and organic matter, is blown by dust storms over long distances and can be deposited as dry or wet fallout in oceans or on land under the dust trajectories.
Salinization often affects highly productive soils under poor irrigation practices. It is therefore a form of dryland degradation which causes particularly high losses of potential crops.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Christiansson, C.: 1981, Soil Erosion and Sedimentation in Semi-arid Tanzania, Scandinavian Institute of African Studies, Uppsala, 208 pp.
Coudé-Gaussen, G., M.-N. Le Costumer, and P. Rognon: 1984, ‘Paléosols d'âge Pléistocene Supérieur dans le loess des Matmata (Sud Tunisien)’, Sci. Géol. Bull., 37, No. 4, 359–386.
Dregne, H. E.: 1983, Desertification of Arid Lands, Advances in Desert and Arid Land Technology and Development, Volume 4, Harwood Academic Publishers, New York, 242 pp.
Eriksson, K. G.: 1965, ‘The Sediment Core No. 210 from the Western Mediterranean Sea’, Report of the Swedish Deep Sea Expedition, 8, 395–594.
Eriksson, K. G.: 1979, ‘Saharan Dust Sedimentation in the Western Mediterranean Sea’, in Morales, G. (Ed.), SCOPE Report 14, 197–209
FAO: 1966, ‘Soil Map of Europe, 1:2.5 million’, Explanatory text by R. Dudal, R. Tavernier and D. Osmond, FAO, Rome.
FAO: 1979, ‘A provisional methodology for soil degradation assessment’, FAO, Rome, 84 pp.
FAO, UNEP and Unesco: 1980, ‘Provisional map of present degradation rates and present state of soil’, FAO, Rome.
Glawion, H.: 1939, ‘Staub und Staubfälle in Arosa’, Beitrage zur Physik der Freien Atmosphare, 25, 1–43.
Goudie, A. S.: 1978, ‘Dust storms and their geomorphological implications’, Journal of Arid Environments, 1, 291–311.
Grigoryiev, A. A. and Kondratyev, K. J.: 1980, 1981, ‘Atmospheric dust observed from space’, WMO Bulletin, 29, 4 and 30, 1.
Haeberli, W.: 1977, ‘Sahara dust in the Alps—A short review’, Zeitschrift für Gletscherkunde, 13, 206–208.
Helldén, U.: 1984, ‘Drought Impact Monitoring: A Remote Sensing Study of Desertification in Kordofan, Sudan’, Rapporter och Notiser, 61, Lund University, Geography Department, 57 pp.
Ibrahim, F. N.: 1979, Desertification, A World-Wide Problem, Hagemann Verlag, Düsseldorf, 30 pp.
Kovda, V. A.: 1983, ‘Loss of productive land due to salinization’, Ambio, 12, 121–123.
Kubiena, W.L.: 1950, Bestimmungsbuch und Systematik der Böden Europas, Ferdinand Enke, Stuttgart.
Lundholm, B.: 1975, ‘Environmental Monitoring Needs in Africa’, African Environment Special Report, International African Institute, London, 9–24.
Morales, C. (Ed.): 1979, Saharan Dust: Mobilization, Transport, Deposition, SCOPE, 14, J. Wiley and Sons, Chichester.
Morgan, R. P. C.: 1979, Topics in Applied Geography: Soil Erosion, Longman, London and New-York, 113 pp.
Olsson, L.: 1983, ‘Desertification or Climate?’, Lund Studies in Geography, Series A: 60, Gleerup, 36 pp.
Parmenter, C. and Folger, D.W.: 1974, ‘Eolian Biogenic Detritus in Deep Sea Sediments: A Possible Index of Equatorial Ice Age Aridity’, Science, 184, 695–697.
Péwé, T. L. (Ed.): 1981, Desert Dust: Origin, Characteristics and Effect on Man, Geological Society of America, Paper 186.
Prodi, F. and Fea, G.: 1978, ‘Transport and deposition of Saharan dust over the Alps’, Verhandlungen 15, International Tagung für Alpine Meteorologie, Schweiz. 1. 179–182.
Prodi, F. and Fea, G.: 1979, ‘A Case of Transport and Deposition of Saharan Dust over the Italian Peninsula and Southern Europe’, Journal of Geophysical Research, 84, 6951–6960.
Prospero, J. M. and Carlson, T. N.: 1972, ‘Vertical and Aerial Distribution of Saharan Dust over the Western Equatorial North Atlantic Ocean’, Journal of Geophysical Research, 77, 2255–2565.
Prospero, J. M. and Nees, R. T.: 1977, ‘Dust Concentration in the Atmosphere of the Equatorial North Atlantic: Possible Relationship to the Sahelian Drought’, Science, 196, 1196–1198.
Rapp A.: 1974, A review of Desertization in Africa—Water, Vegetation and Man, Secretariat for International Ecology (SIES), Sweden, Report 1, 77 pp.
Rapp, A.: 1983, ‘Are Terra Rossa Soils in Europe Eolian Deposits from Africa?’, Geolog. Fören., Stockholm Förhandl., (GFF) 105, 161–168.
Rapp, A., Berry, L. and Temple, P. H. (Ed.): 1972, ‘Studies of erosion and sedimentation in Tanzania’, Geograf. Annaler, 52, 3–4.
Rapp, A., Le Houérou, H. N. and Lundholm, B.: 1976, Can Desert Encroachment Be Stopped? A study with emphasis on Africa, Ecological Bulletin No. 24, Chapter 12.
Tomasi, C., Prodi, F. and Tampieri, F.: 1979, ‘Atmospheric Turbidity Variations Caused by Layers of Sahara Dust Particules’, Contributions to Atmospheric Physics, 52, 215–228.
UNCOD: 1977a, ‘Plan of action to combat desertification’, Chapter 1 in document A/Conf. 74/36, 2–63, UNEP, Nairobi.
UNCOD: 1977b, World map of desertification, UNCOD document A/Conf. 74/2, UNEP, Nairobi.
Yaalon, D. and Dan, J.: 1974, ‘Accumulation and Distribution of Loess Derived Deposits in Semi-Desert and Desert Fringe of Israel’, Zeitschrift für Geomorphologie, Supplement band, 20, 91–105.
Yaalon, D. and Ganor, E.: 1973, ‘The Influence of Dust on Soils During the Quaternary’, Soil Science, 116, 146–155.
Yaalon, D. and Ganor, E.: 1979, ‘East Mediterranean Trajectories of Dust Carrying Storms from the Sahara and Sinai’, in Morales, C., (Ed.), SCOPE, Report 14.
Yair, A.: 1984, ‘The Environmental Effects of Loess and Sand Penetration into the northern Negev Desert’, 25 th International Geographical Congress, Symposium S.Y.4, Strassbourg (Abstract, p. 66).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Rapp, A. Introduction to soil degradation processes in drylands. Climatic Change 9, 19–31 (1986). https://doi.org/10.1007/BF00140521
Issue Date:
DOI: https://doi.org/10.1007/BF00140521