Pereira, H Charles
Sir (Herbert) Charles PEREIRA 1913 (London, UK) - 2004 (Teston, Kent, UK)
Born in London, Pereira —who was always known as Perry to friends and colleagues— was taken, with his younger brother Ronald and sister Maudie, by his parents to Canada, initially to the prairies and later to a remote outpost of Cree Indians on Montreal Lake in northern Saskatchewan where his father, a schoolmaster sponsored by the Church of England Missionary Society, had been appointed ‘Government Agent’. As a schoolboy, Perry revelled in driving a covered wagon drawn by four horses across the muskeg in a delivery of mail and stores to their remote settlement. The nearest school was five wagon days away in Prince Albert, so the Pereira boys were taught at home before secondary education at the Collegiate Institute in Prince Albert. However, when Perry was 15 years old, the family returned to England to facilitate a less adventurous lifestyle and, for the children, a more conventional education in St Albans school. Perry’s university education was at Goldsmiths’ College, London, where he gained an upper-second-class honours degree in physics and math-matics (together with university colours for boxing as light-heavyweight). After a school visit to the Rothamsted Experimental Station, he was inspired to study soil physics for a London University internal PhD there. In the absence of research grants in these prewar days, he funded his research by taking a post as Assistant Bursar at Ottershaw College, where he set up a field experiment in the grounds of the school and studied at Rothamsted in the long school vacations.
In the footsteps of his father, H. J. Pereira, in World War I, Perry joined the Royal Engineers just before the outbreak of World War II. By then his PhD thesis was nearly complete; he was appointed a Company Commander and later, as Captain RE, he was given leave to attend his doctoral viva in London. Formal notification of the award of his degree was delivered by a motorcycle dispatch rider to the SS Cameronia, on which he was embarking for South Africa en route to Suez with a group of sapper reinforcements.
In postwar terminology, Perry had a ‘good’ war in that all his training and professional experience proved relevant and appropriate. In the Western Desert, in Egypt and Libya west of the Nile, he exploited his knowledge of soil physics to consolidate salt marshes as alternative airstrips when airfields were bombed. To start a series of intensive training courses for officer cadets, Perry was transferred to the School of Military Engineering. Then, to gather information relevant to a possible German advance through Turkey to Egypt and the Suez Canal, Perry was sent to reconnoitre potentially defensive positions through Palestine, Lebanon, Turkey, Syria, Iraq, Iran and Jordan. On his return to Cairo, he liaised between General Headquarters and Field Marshall Montgomery’s Eighth Army at El Alamein. Thereafter, as GSO 2 (General Service Officer), second in command to Major General H. B. W. Hughes he was involved in planning for the landings in Sicily and later in Italy, where the sappers’ speedy replacement of bridges destroyed by the enemy was critical in the advance to and beyond Monte Cassino. Unfortunately, Perry’s previously charmed life was interrupted by accurate fire from a German 88 mm battery; rescued from under his overturned staff car, he was invalided back to the UK to recover from a serious leg injury. Soon he was spending hours a day in the gymnasium and on the running track until he was fit for light duties; eventually he was posted to Rhine Army as GSO 2 to Brigadier S. Batten for the crossing of the Rhine. Perry was ‘Mentioned in Dispatches’.
During his wartime travels in the Middle East, Perry had noted challenges and therefore had opportunities for soil physical research in semi-arid countries. So, after the war, he decided on colonial service as a career. While still on release leave, he accepted a post in coffee research at Ruiru near Nairobi in Kenya. The post offered was that of a soil chemist; for this, his experience at Rothamsted and the application of the novel statistics recently developed there contributed valuable initiatives to studies of the effects of fertility, fertilizers and mulches on coffee. All these were written up and published in international journals of experimental agriculture and soil science. However, in East Africa, water is the principal requirement for growth of all crops; with adequate water, most crops prosper; without it, few survive. Although research in soil chemistry might well improve crop yields, Perry realized that research in soil water relations was much more likely to satisfy the UK Secretary of State’s declared ambition ‘to make two blades of grass grow where only one grew before’. Perry realized that enlightened management of the high-altitude, high-rainfall water catchment areas was crucial to improving agricultural productivity in the semi-arid farmlands and rangelands at lower altitudes downstream.
When the colonial administrations in Kenya, Uganda and Tanganyika established the East African High Commission to operate common services, such as railways, airways, postal services and tax collection, major centres were established for veterinary, fisheries and agricultural and forestry research, but water resources management was not included. Between the departments of water development and of forestry there was controversy over the optimal land use for vital high-altitude water catchment areas. In the meantime, Sir Bernard Keen FRS, then Director of the East African Agriculture and Forestry Research Organization (EAAFRO) at Muguga in Kenya, appointed Perry to found a laboratory of soil physics to study soil structure and tillage as well as soil moisture, radiation and evaporation. Subsequently, Perry published numerous papers on the development of techniques and their subsequent application to crop cultivation practices as well as on assessing the water requirements of a wide diversity of crops and natural vegetation. He was soon promoted to be Deputy Director of EAAFRO.
Thereafter he was appointed Director of the UK East Malling Research Station (1969–72) and then Deputy Secretary and Chief Scientist in the Ministry of Agriculture, Fisheries and Food (MAFF) (1972–77). He served on the Natural Environment Research Council (1971–77). In 1971, he participated in the establishment of the Consultative Group for International Agricultural Research (CGIAR) and was a founder member of its influential Technical Advisory Committee. He was made a Fellow of the Royal Society in 1969. After retiring from MAFF in 1977, he was knighted and for a further 25 years he undertook a heavy schedule of international travel, consulting, reviewing and advising on projects on improving the management of land use and water resources in many parts of the world.
Long before the International Hydrological Decade was proposed by the United Nations Educational, Scientific and Cultural Organization (UNESCO), at a regional planning meeting at EAAFRO involving the heads of the departments for water and forestry in Kenya, Uganda and Tanganyika it was proposed that the EAAFRO Physics Division might act as the central coordinating and analytical team for major cooperative research projects on water catchment areas, investigating the hydrological consequences of changes in land use in the high-rainfall areas in the East African countries and in rangeland. Each study was chosen to address a particular land-use problem and would help to resolve the controversy over whether forests use more water than crops, which was then engaging the departments of water and forestry. Moreover, the set of projects would be innovative and particularly appropriate for the EAAFRO Physics Division, largely because the relevant national department would fund and staff each experiment locally. Four comparative studies of land use were agreed by the Planning Committee:
(i) the water use of bamboo forest versus pine plantations in the Kenya Aberdares (source of water for Nairobi city);
(ii) the water use of montane rain forest versus tea plantations in Kericho, Kenya (draining to Lake Victoria);
(iii) the water use of montane rain forest on steep slopes versus subsistence agriculture near Mbeya, Tanganyika; and
(iv) the water use of overgrazed semi-arid rangeland versus controlled grazing in Karamoja, Uganda.
Initial results of these experiments were presented at an East African Hydrological Conference in 1961 and published in a special issue of the East African Agriculture and Forestry Journal. Also in 1961, Perry was awarded a DSc from London University for his original contribution to what was then recognized as a new field of science. Subsequently, he was appointed Director of the ARC of Rhodesia and Nyasaland. In East Africa, after the independence of the individual countries, the catchment area studies were continued with the support and guidance of the UK Natural Environment Research Council’s Institute of Hydrology (Blackie et al. 1979). In 1990 UNESCO described the results of these East African catchment area experiments as ‘the world’s only reliable data on the tropical mountain hydrology of land-use change’.
What, then, were the outcomes of these many years of measurement and analysis of all the components of the hydrological cycle in the four catchment experiments? The Kenya projects found no significant difference in the water use of (i) pines and bamboo and (ii) tea gardens and montane rain forest; in each case the water use of adequately watered vegetation completely covering the ground proved to be very similar. In the Uganda project (iii) on over-grazed semi-arid bush or scrubland, grazing control reinstated the former grass cover within two years, which doubled the potential stocking rate of cattle and therefore the productivity of the experimental catchment. In Tanganyika, the comparison (iv) of tall forest versus subsistence agriculture on very steep hillsides near Mbeya showed how, in the cultivated catchment, contour planting of crops on simple terraces made by trash lines of dead vegetation and weeds increased rainfall infiltration into the soil and so reduced erosion, and short cropping seasons minimized the water use. However, the water consumption of the forest in the control catchment was much greater than expected because the deeply rooted trees took full advantage of the moisture stored in the deep soils.
In the effective establishment and management of such a wide-ranging programme of studies of land use involving personnel and funding from numerous government departments in three countries, Perry’s outstanding competence in organization of research had led to his being invited to take on the role of Director of the new ARC of Rhodesia and Nyasaland. On his arrival, in June 1961, he had found that, although the Director’s salary was generous, the funding available for the Council was minimal. Indeed, much of the responsibility of the new post was both to attract essential funding from diverse sources and to establish closer cooperation and collaboration with the research facilities then operating in the Central African countries. This avoided the unnecessary duplication of buildings and facilities; new research units were created only where there were obvious gaps in the existing arrangements. These were, in Northern Rhodesia (later renamed Zambia) an animal productivity unit and a laboratory for forest genetics, in Nyasaland (later Malawi) a laboratory to investigate viral disease resistance in groundnuts and grain legume pathology, and in Southern Rhodesia (later Zimbabwe) a soil science and soil productivity laboratory. By 1967 the ARC was functioning smoothly and efficiently; its new units were fully staffed and funded, and they operated to the satisfaction of the relevant national governments. Then Zambia withdrew from the Central African Federation and the UK declined to continue support for Rhodesia and Nyasaland. Hence, in September 1967, the ARC was broken up. Subsequently, both Malawi and Zambia established their own national ARCs and invited Perry to attend as the chairman in Malawi and as an observer in Zambia. Before returning to the UK in 1969, Perry wound up the residual affairs of the ARC; he reviewed the results of its research, analysed the data and published 30 research papers in two issues of the Rhodesia, Zambia and Malawi Journal of Agricultural Research, later called the Zimbabwe Journal of Agricultural Research, which Perry had founded in 1963 and continued to edit until 1967. However, an enterprising network of research centres on natural resources in both East and Central Africa lost momentum and cohesion when dedicated expatriate staff were replaced by less experienced Africans ((5), p. 63).
The International Hydrological Decade (IHD) had been established in 1965 by UNESCO, and Perry had been asked to chair the Working Group on the Influence of Man on the Hydrological Cycle. In 1968, the Council of the IHD invited Perry to undertake a world tour to assemble information on practical examples of advances in catchment management. Visits to Europe, the UK, the USA, Trinidad, Argentina, the USSR, Kenya, Uganda, Mauritius, Australia and Sri Lanka briefed him extensively on research ongoing in catchment hydrology. His report to the IHD Council was commended in 1969 and was the basis for his book "Land Use and Water Resources"