Volume 55 No 2 April 2007 - New Zealand Society of Soil Science

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A history of soil survey and selected aspects of soil conservation in New Zealand Part one Dr P.J. Tonkin Senior Fellow Department of Geological Science University of Canterbury. Email The gardeners from the Pacific Maori migrated from tropical Oceania to temperate Aotearoa where their gardeners had to discover soils suited to growing kumara, taro, yam, and gourd. Some soils were modified to improve growing conditions. Northern areas had familiar reddish brown soils formed on weathered volcanic ash and scoria and volcanic rocks. Fertile and well-drained soils on flat to rolling country were of great importance. Elsden Best lists Maori names used to distinguish soils emphasizing soil colour and texture, soil fertility, ease of cultivation and drainage conditions. Examples are: Tuatara wawata (brown friable fertile, suitable for kumara), One paraumu (very dark fertile friable), One kura (reddish poor), Kerematua (stiff clay) and One kopuru (wet situations). The early colonial period Early European visitors to New Zealand, impressed by the lush forests, assumed erroneously they were growing on fertile soils. Dr Ernst Dieffenbach noted the geological origin of some soils in Chatham Islands and in New Zealand. Surveyors and missionaries recorded their impressions of soils under cultivation and by 1840 these observations were included in information for prospective colonists. The correlation of soil fertility with vegetation size, such as in the northern kauri forests, proved to be a fallacy leading to the adoption of specific plant indicators of soil fertility, such as puriri trees, said to be an indicator of fertile soils developed on basaltic tuffs in North Auckland. In the period 1840 to 1850, studies in United Kingdom and Europe of chemistry and plant nutrition, changed the approach to soil analysis. In New Zealand Europeans with geological knowledge made attempts to sample soils for analysis. These included Dr Ferdinand von Hochstetter when visiting Auckland Province in 1859. A geological survey, established in Otago by James Hector during the 1860s gold rush, had a laboratory staffed by C.S. Wood and subsequently by William Skey. Hector moved to Wellington in 1865, establishing the Colonial Museum and Laboratory with Skey as Government analyst. Skey continued as Government analyst when he transferred to the Mines Department in 1893. A chemical approach to soil fertility Skey offered free soil analyses, comparing results with standard works of the European chemist Justus von Liebig, and in 1868 reported analyses of 33 soils, giving texture, constituents soluble in water, and fairly complete analyses of hydrochloric acid extracts. This first was New Zealands first chemical ‘soil survey’ and formed part of a suitability assessment of lands for European settlement. In 1900 Bernard C. Aston was appointed to the new Chemistry Division of the Department of Agriculture located in Wellington. He modified soil analysis in the light of an 1899 study of soils on the Taupo Plains. He advocated a systematic soil survey of New Zealand, and between 1903 and 1906 initiated a reconnaissance ‘flying soil survey’ combined with pot tests of soils to examine nutrient deficiencies. His aim was to identify, but not map, the predominant soil types of a district from a consideration of climate and surface conditions, geological origin, physical and chemical characteristics, vegetation, and recognized economic adaptations. The soil in place, rather than in the laboratory, was Aston’s approach. Between 1908 and 1909, he modified the chemical methods for assessing plant available nutrients in the soil and with the co-operation of farmers, instituted a nation-wide series of soil fertility field experiments to a set design. The beginning of soil survey in New Zealand In 1899 the United States Department of Agriculture (USDA) established the National Cooperative Soil Survey, the first government funded programme in the world. Initially the emphasis was on the soils assumed geological origins and the surface soil horizon. The first soil maps in the United States 59
and England were published by 1911. In New Zealand Aston, Leonard J. Wild and Hartley T. Ferrar aware of these developments promoted the idea of establishing a soil survey. Ferrar, a geologist arrived in New Zealand in 1920 with experience of surveying arid soils in Egypt. Wild published a soil survey of the Wairau Plains in 1914, using symbols to the different the soils on his map but did not delineate the unit boundaries. In 1916 he proposed a soil survey of New Zealand in which subdivisions would be based initially on climate and geological structures, with soil analyses in 0-15 cm and 15-30 cm depth increments accompanied by a sketch of the soil profile. Investigations into bush sickness By 1911 Aston had published the first of a long list of studies on the chemistry of bush sickness, an illness affecting sheep and cattle on certain areas of the pumice country and adjacent areas of the central North Island. In 1912 an iron deficiency was thought to be the cause of bush sickness. This began a period of scientific investigation of metabolic diseases in plants and animals, by Aston’s group, and after 1920 by Theodore Rigg and others at the Cawthron Institute in Nelson. They highlighted the need for a systematic examination and mapping of soils. Wild and Aston separately, assessed the suitability of soils for pastures and crops by forming classes using particle size with supporting chemical analyses of selected surface and subsurface soil samples. Agrogeological surveys Ferrar undertook agrogeological surveys in Northland in 1922, Central Otago in 1926 to 1928 and in the King Country between 1928 and 1932. Norman H. Taylor was employed as a casual field assistant on the Central Otago survey and was subsequently appointed as an assistant geologist to Ferrar on the King County survey. In 1926 Ferrar wrote, “soils must be mapped, texture and parent material are key factors, climate is of primary concern but geology must be the basis”. His 1929 report on the soils of the irrigation areas in Central Otago, cites methods of soil survey developed in the United States and he adapts their method of soil classification: “which is based primarily upon the rock or rocks from which they are derived, and upon their mode of origin; and secondarily upon such properties as colour, content of organic matter, natural drainage &c.” Ferrar and Aston were the first to propose the adoption of the soil type as a soil mapping unit, where like soil types, distinguishable only on the basis of texture, could be grouped into soil series, and at the highest level into soil provinces, as was done by Dr Curtis F. Marbut in the National Cooperative soil survey in the United States. Renewing the call for a national soil survey Aston again promoted the idea of a national soil survey in 1923, suggesting soils should be identified by locality name and texture, and that different levels of detail be employed. He undertook further studies of the pumice soils in Rotorua County between 1926 and 1929, producing a soil map that emphasized soil texture, and recognized some of the contrasting volcanic ash deposits. Rigg, who in 1920 was appointed as an agriculturalist at the Cawthron Institute, brought experience of soil survey from university studies at Cambridge (UK), Cornell (USA) and elsewhere in the United States. He introduced a technique for field soil texturing and the use of the hand auger to examine the soil profile. Rigg and J.A. Bruce began the first systematic soil survey in New Zealand, mapping the soils of the Waimea County in the Nelson District. The original map, dated 1922, is held in the Cawthron Institute in Nelson and shows twenty-three soil series and forty-three texturally distinguishable soil types. Mapping the bush sick soils By the late 1920s there was an urgent need for a solution to the problem of bush sickness on the volcanic pumice and ash deposits of the central North Island. Leslie I. Grange, of the New Zealand Geological Survey, was mapping the geology of Rotorua County in the course of which he identified and mapped a number of volcanic ash deposits. Regrouping soils, previously described by Aston and Richard E. R. Grimmett, Grange confirmed the incidence of bush sickness on soils formed from the Taupo and Kaharoa ash showers (pumice and ash deposits). In the King Country Taylor was able to demonstrate a relationship between animal ill thrift and soils developed on the Mairoa ash shower in areas of high rainfall. Taylor’s Mairoa ash shower is now regarded as a composite of many thin volcanic ash layers. The recognition that animal ill thrift was restricted to the high rainfall areas indicated that the process of soil leaching was significant and resulted in induced ailments in animals. This ill thrift condition was subsequently shown to be the same as the bush sickness associated with the Taupo and Kaharoa ash deposits of the central North Island. The studies of Grange and Taylor 60
Page 1 and 2: Obituaries Ken Lee and Colin Vuceti
Page 3 and 4: ***Your contributions are required*
Page 5 and 6: The need for this knowledge is a cl
Page 7 and 8: Vince Neall - Massey University The
Page 9 and 10: Percy Sladen Expedition to the New
Page 11 and 12: articles Soil Biology: A Core New Z
Page 13: New Zealand Society of Soil Science
Page 17 and 18: Studying soil formation In 1933 Tay
Page 19 and 20: By the mid 1940s Taylor had formali
Page 21 and 22: processes, and facilitated the stud
Page 23 and 24: surveys of Christchurch, Dunedin, P
Page 25 and 26: Dr Clifford V. Fife started at Mass
Page 27 and 28: David Houlbrooke, Alison Rutherford
Page 29 and 30: Professor Gerold Wefer from the Uni
Page 31 and 32: Lincoln University We welcome Dr Ti
Page 33 and 34: The technical committee believes th
Page 35 and 36: Soil News Editor Iris Vogeler and I
Page 37 and 38: one of the organising committee mee
Page 39 and 40: Recording another soil, John Bruce
Page 41 and 42: Nitrous oxide (N2O) is a potent gre
Page 43 and 44: Upcoming Conferences SOIL - The liv
Page 45: Job vacancies Soil chemist position

Volume 55 No 2 April 2007 - New Zealand Society of Soil Science

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