Global extent, development and economic impact of acid soils
- 2.2k Downloads
Acid soils occupy approximately 30% or 3950 m ha of the world's ice free land area and occur mainly in two global belts where they have developed under udic or ustic moisture regimes. The northern belt (cold and temperate climate) is dominated by Spodosols, Alfisols, Inceptisols and Histosols and the southern tropical belt consists largely of Ultisols and Oxisols.
Sixty-seven percent of the acid soils support forests and woodlands and approximately 18% are covered by savanna, prairie and steppe vegetation. Only 4.5% (179 m ha) of the acid soil area is used for arable crops. A further 33 m ha is utilized for perennial tropical crops. The value of the annual production in these areas is approximately US$ 129 billion. Value of products from forests, woodlands and permanent pastures on acid soils is difficult to evaluate.
Forests of the tropics and wetlands have an invaluable role in global, regional and local ecosystem balance and a protective role for flora, fauna and water resources. While acid soils in the northern belt are increasingly protected and reafforested, the destructive exploitation of timber and abusive modern shifting cultivation have contributed to the loss of >250 million ha of tropical forest during the second half of this century leaving vast areas of anthropic savannas on heavily eroded and degraded acid soils.
The authors believe that attempts to develop acid soils for agriculture and agroforestry in the tropics should concentrate on these deforested and abandoned areas of degraded acid soils. However, this will be difficult without significant initial investment and adequate technology. A three step development approach is suggested, which could help prevent or halt the annual destruction of >5 mill. ha tropical forests by “untraditional shifting cultivators’. It would help to protect the fragile natural ecosystems on tropical acid soils now considered to be indispensable for the future life on earth.
Key wordsdeforestation savanna tree crops tropics
Unable to display preview. Download preview PDF.
- Abrol I P 1982 Reclamation of waste lands and world food prospects. In Wither Soil Research. pp 317–337. International Congress Soil Science, New Delhi, India.Google Scholar
- Alvim P T 1977 The balance between conservation and utilization in the humid tropics, with special reference to the Amazonia of Brazil. In Extinction is Forever. Eds. G T Prance and T S Elias. pp 347–352. New York Botanical Gardens, NY, USA.Google Scholar
- Bolan N S, White R E and Hedley M J 1990 A review of the use of phosphate rocks as fertilisers for direct application in Australia and New Zealand. Aust. J. Exp. Agric. 30, 297–313.Google Scholar
- Breburda J 1990 Development of agricultural yield levels and soil K-status in Eastern and Western Europe. In Development of K Fertilizer Recommendations. pp 17–35. International Potash Institute, Switzerland.Google Scholar
- Buringh P, van Haenst H D T and Staring Y J 1975 Computation of the absolute maximum food production of the world. Agriculture University, Wageningen, Netherlands.Google Scholar
- Coleman N T and Thomas W G 1967 The basic chemistry of soil acidity. Agron. Monogr. 12, 1–41.Google Scholar
- Craswell E T 1986 Soil management in Asia: research supported by the Australian Centre for International Agricultural Research. In Soil Management Under Humid Conditions in Asia. Ed. M Latham. pp 53–67. Asialand, IBSRAM Proceedings No. 5, Bangkok, Thailand.Google Scholar
- Dudal R 1988 Changing patterns in the utilization of upland soils in the tropics and subtropics. In Management and Fertilization of Upland Crops in the Tropics and Subtropics. pp 1–5. Nanjing Institute of Soil Science, Nanjing, PRC.Google Scholar
- FAO 1969 Provisional World Plan for Agricultural Development. Rome, Italy.Google Scholar
- FAO 1991a Production Yearbook, 1990. Vol 44. Rome, Italy.Google Scholar
- FAO 1991b World Soil Resources Report 66. Rome, Italy.Google Scholar
- FAO 1992 Production Yearbook, 1991. Vol 45. Rome, Italy.Google Scholar
- International Land Development Consultants (Eds.) 1981 Agricultural Compendium for Rural Development in the Tropics and Subtropics. Elsevier, Amsterdam, The Netherlands.Google Scholar
- Jackson W A 1967 Physiological effects of soil acidity. Agron. Monogr. 12, 3–124.Google Scholar
- Jackson T L and Reisenauer H M 1984 Crop response to lime in Western United States. In Soil Acidity and Liming. Ed. F Adams. pp 333–347. ASA, CSSA, SSSA, Madison, WI, USA.Google Scholar
- Mengel K and Steffens D 1985 Beziehung zwischen Kationen/Anionen-Aufnahme von Rotklee und Protonenausscheidung der Wurzeln. Z. Pflanzenernähr. Bodenkd. 145, 229–236.Google Scholar
- Ruhiyat D 1989 Die Entwicklung der standortlichen Nahrstoffvorrate bei naturnaher Waldbewirtschaftung und im Plantagenbetrieb, Ost-Kalimantan (Indonesien). Diss., Gottinger. Beitrage zur Land-und Forstwirtschaft in den Tropen und Subtropen, Heft 35, Gottingen, Germany.Google Scholar
- Rust R H 1983 Alfisols. In Pedogenesis and Soil Taxonomy. The Soil Orders. Eds. L P Wilding, N E Smeck and G F Hall. pp 253–281. Elsevier, Amsterdam, The Netherlands.Google Scholar
- Sanchez P A 1976 Properties and Management of Acid Soils in the Tropics. John Wiley and Sons, New York, USA. 618 p.Google Scholar
- Sanchez P A 1987 Management of acid soils in the humid tropics of Latin America. In Management of Acid Tropical Soils for Sustainable Agriculture. IBSRAM Proc No. 2. pp 63–107. Bangkok, Thailand.Google Scholar
- Sanchez P A and Benites J R 1987 Low-input cropping for acid soils of the humid tropics: a transition technology between shifting and continuous cultivation. In Africaland: Land Development and Management of Acid soils in Africa II. Eds. M Latham and P Ahn. IBSRAM Proceedings No. 7. pp 85–106. Bangkok, Thailand.Google Scholar
- Stangel P and von Uexküll H R 1990 Regional food security: demographic and geographic implications. In Phosphorus Requirements for Sustainable Agriculture in Asia and Oceania. Ed. IRRI. pp 21–43. IRRI, Los Baños, Philippines.Google Scholar
- Tamm C O and Andersson F 1989 Swedish forests in a changing environment. In Environmental Threats to Forest and Other Natural Ecosystems. Ed. I Szabolcs. pp 13–24. Budapest, Hungary.Google Scholar
- Tyler G 1989 Effects of soil acidification and nitrogen deposition on forest biota. In Ecological Impact of Acidification. Ed. I Szablocs. pp 61–66. Budapest, Hungary.Google Scholar
- US Report 1967 The World Food Problem. A report of the President's Science Advisory Committee. Vol II. Washington DC, USA.Google Scholar
- Van Breemen N 1980 Acidity of wetland soils, including Histosols, as a constraint to food production. In Priorities for Alleviating Soil-Related Constraints to Food Production in the Tropics. Ed. IRRI. pp 189–202. IRRI, Los Baños, Philippines.Google Scholar
- Van Wambeke A H, Eswaran H, Herbillon A J and Comerma J 1983 Oxisols. In Pedogenesis and Soil Taxonomy. II. The Soil Orders. Eds. L P Wilding, N E Smeck and G F Hall. pp 325–354. Elsevier, Amsterdam, The Netherlands.Google Scholar
- Von Uexküll H R and Bosshart R 1989 Management of acid upland soils in Asia. In Management of Acid Soils in the Humid Tropics of Asia. Eds. E T Craswell and E Pushparajah. ACIAR Monograph No. 13, pp 2–13. ACIAR, Canberra, Australia.Google Scholar
- Von Uexküll H R and Mutert E 1993 Rehabilitation of anthropic savanna. In Phosphorus Cycles in Terrestrial and Aquatic Ecosystems. Budapest, Hungary.Google Scholar
- Williams C H 1980 Soil acidification under clover pastures. Aust. J. Exp. Agric. Anim. Husb. 20, 561–567.Google Scholar
- Williams C H 1990 The management of problem soils in Australia. In Problem Soils of Asia and the Pacific. FAO. pp 68–103. Bangkok, Thailand.Google Scholar
- World Wildlife Fund (WWF) International 1989 Tropical Forest Conservation. Geneva, Switzerland.Google Scholar