Sri Lanka is a tropical Island in the Indian ocean at 790 39' to 810 53' E and 50 54' to 90 52' N consisting of a land area of 65,525 km2 with a population of 19 million. The country was under colonial rule from 1505 to 1948. The majority of the people in the past and present earn their living from activities based on land which indicates the important of the soil resource. The objective of this paper is to explore the landmarks of the history of Soil Science, specially the soil survey and mapping work, to highlight the achievements and failures, which is useful to enrich our present understanding of Sri Lankan soils.

The landmarks or the phases of the history can be divided to four phases, namely, the early analytical period which is prior to 1925, the genetic, soil profile and reconnaissance phase from 1930 to 1950, the Canada-Ceylon aerial resource survey phase from 1955 to 1960 and the modern era of Soil Survey and Classification since 1960. During the early period detailed analytical studies of coffee and tea soils were compiled, and these gave mainly information on up-country soils of the island and fertilizer recommendations for these two crops based on field trials. In addition rice and forest soils were also studied in less detail. During 1930 to 1950, the second period, soils of Sri Lanka were studied based on the genetic concepts of Russian workers as reflected in the soil profile. During this time many soil surveys of areas proposed for development under irrigation schemes were commenced. Based on these data and using the geological and meteorological maps, the first genetic classification of Sri Lanka soils and a provisional map showing distribution of 16 major soil series were published. During the third period of 1955-1960, valuable information on the land resource was collected by aerial resource surveys from a Canada-Ceylon Colombo plan aid project. This covered 18 major river basins and about 1/4th of the island, which resulted in producing an excellent soil map and information of the area called the Kelani Aruvi report... The modern era, since 1960 to present showed the highest period of development in Soil Science in Sri Lanka. In 1972, the updated soil map of Sri Lanka consisting of Great Soil Groups and Soil Taxonomic equivalents according to United States Department of Agriculture was published with the Handbook of Soils of Sri Lanka (Ceylon) by the Soil Science Society of Sri Lanka. Excellent work was also conducted by the Department of Agriculture and Irrigation, various research institutes such as Tea, Rubber, Coconut and Sugarcane Research Institute and the Universities. These included investigations on soil fertility, physical & chemical properties, nature of organic matter, macro and micro nutrient status, mineralogy and their distribution and classification. The Coconut Research Institute studied the coconut growing soil in detail and mapped them according to yield potential.

A major leap forward in Soil Survey, Classification and development of a soil data base was initiated in 1995 with the commencement of the “SRICANSOL” project which was a twining project between the Soil Science Societies of Sri Lanka and Canada. Phase I and II of this project is now completed with detail soil maps at a scale of 1:250,000 and 1:40,000 for the Wet and Intermediate Zones of Sri Lanka, respectively. The database consists of soil profile data and physical and chemical properties of a benchmark site for each series identified. The soils are classified according to current systems such as Soil Taxonomy and the FAO classification. The mapping and development of the database for the dry zone of Sri Lanka will be completed soon. These databases will be useful in land use planning, where environmental sustainable agriculture could be practiced in these soils.

This account of landmarks of the history of Soil Science in Sri Lanka shows the developments during the last century. The emphasis should now change in using the soil information to address the major environmental problems in the country which are soil erosion and pollution of ground water by agricultural activity. This will lead to better development of agri-environmental health in the country in the future.