４５５：イアン・カルダ―氏死去

数年前に東大の蔵治先生らが翻訳された「水の革命 ― 森林・食糧生産・河川・流域圏の統合的管理」の作者であるイアン・カルダ－の死去を偶然知った。

前回の繋がりもあり奇遇である。カルダー氏はイギリスを代表とする森林水文学者であり、南部アフリカの水文にも大きな貢献をされた方だ。日本でもご存知の方が多いと思う。

１９４５年生まれだから６４歳で亡くなられたことになる。イギリス水文学会にとっては大きな損失と言えよう。IWRMの推進にも大きな影響を与えたはずである。下記にイギリス水文学会のObituaryを示す。

Ian Rainy Calder (1945-2009) – Obituary

Ian Calder was a renowned and admired scientist who greatly expanded our understanding of forest hydrology and who applied his expertise to land use and integrated water resources management and to overseas development issues in hydrology.

He graduated in Special Physics at Leeds University in 1968 and completed a PhD in Cosmic Ray Physics there in 1971. After a brief spell as a Scientific Control Systems (SCICON) Operations Research Consultant, he turned his talents in physics to hydrology by joining, in 1972, the Soil Physics section of the then Institute of Hydrology (IH) at Wallingford (now the Centre for Ecology and Hydrology).

He rapidly developed an expertise in combining meticulously designed field experiments using novel measuring techniques, with physically-based process modelling. He instigated a natural lysimeter at Plynlimon, following the early lead of Frank Law at Stocks reservoir as well as that of the IH Director, Jim McCulloch, in East Africa. He supplemented the lysimeter readings by using the relatively new IH neutron probe to measure soil water changes and designed sheet gauges to determine net rainfall under tree canopies. Combining these measurements with application of the Rutter canopy water balance model and the results of complementary tree physiology and grassland water vapour flux experiments by the late John Roberts (also of IH) he was able to demonstrate convincingly the interception mechanism by which forests may use more water than grasslands. A generalised forest water use model was developed (with Malcolm Newson) for use across Britain.

A very exciting moment, almost a decade later, came when Ian, Peter Walsh and Malcolm
Newson climbed to an attic at Stocks Reservoir to discover all of Frank Law's unpublished lysimeter and catchment data, which they subsequently wrote up as independent confirmation of the Plynlimon findings. Promoted (in 1976) to Head of the IH Process Interactions Section, Ian led further studies in forest hydrology at the Plynlimon and Balquhidder catchments, where his skills in applying new techniques led to the successful deployment of gamma ray attenuation for the measurement of snow interception on forest canopies.

In 1986 he was seconded from IH to be the Chief Water Resources Officer in Malawi, a post he held for three years. This appointment fostered his concern for the water resources of developing countries and, on his return to IH, led to his appointment in 1989 as Hydrology Adviser to the UK government’s Overseas Development Administration (ODA), the forerunner of the Department for International Development (DfID). As adviser he steered ODA towards recognising the importance of water in many developing countries and of the subtle interactions between land and water resources management.

During this time he led a major multi-disciplinary project investigating the water use of eucalyptus plantations in India and, as part of this, he developed the deuterium tracing technique to measure the water use (transpiration) of individual trees. Subsequently (from 1993), as Head of IH’s Land Use and Experimental Hydrology Division, he expanded IH’s already considerable reputation in the impact of forest planting across the world.

In 1998, he followed the northward route to Professorship for former IH staff pioneered by Enda O’Connell, Malcolm Newson and Keith Beven, joining the former two at Newcastle University to become Professor of Land Use and Water Resources Management and Director of the Centre for Land Use and Water Resources Research (CLUWRR).

CLUWRR was initially an umbrella organization for integrating the research activities of the Civil Engineering, Geography and Agricultural Engineering Departments. Under Ian’s leadership, though, the Centre developed particular expertise in integrated land and water resources management and overseas development issues. Notably CLUWRR was commissioned by DFID’s Forestry Research Programme to establish a unit to co-ordinate a cluster of projects focusing on the impacts of forests on water supply and quality. These include projects in South Africa, Tanzania, Grenada, India and Costa Rica. Other projects included:- the impact on the Panama Canal of the reforestation of the Canal catchment; the water resource, societal, biodiversity and carbon sequestration impacts of biofuel plantations;
and the water use of different forest species in Europe under present and future climatic conditions.

Ian also continued his own scientific contributions, especially to interception modelling through the development of an innovative stochastic model of interception loss and the extensive application of his HYLUC model to catchment water balance and water resources problems. Ian did not shirk controversy where he believed the science contradicted popular perceptions and was a strong promoter of evidence-based policy. As countries from China to Central America blamed floods on deforestation, Ian led an international debate emphasizing that the attribution of major flood impacts to deforestation was not supported by the evidence.

Ian was not only an excellent scientist but had a facility for developing relationships with the major funding and management organizations for land and water resources management, including the World Bank, Food and Agriculture Organization, DfID and corresponding government agencies in all continents. He was the International Task Force Leader for Forest and Water Interactions in the International Union of Forest Research Organizations (IUFRO).

He travelled widely in his work, especially to India, Malawi, South Africa, Panama, Costa Rica, Indonesia, China, Norway, Zimbabwe, Tanzania, Sri Lanka, New Zealand and
Vietnam, and of course within the UK. Despite his considerable reputation in the UK, he was perhaps even more widely known abroad, often called upon to present talks at major international conferences at a range of venues. Upon the announcement of his death, messages of sympathy were received from around the world, extolling his personal qualities as much as his scientific standing.

Ian published extensively. He will be remembered particularly for his books “Evaporation in the Uplands” (1990), which distilled much of his experience in Wales and Scotland, and “The Blue Revolution” (1999, 2005), which discussed land use and integrated water resources management, drawing upon his wide international experience and critically examining the basis for some of the public misperceptions concerning the hydrological effects of forests. He was Managing Editor of the e-journal “Land Use and Water Resources Research” and an Associate Editor of the “Journal of Hydrology” and of “Tree Physiology”. He was a Visiting Professor at Loughborough and Birkbeck Universities.

Ian was convivial and resourceful on his travels. On at least one trip to Plynlimon, leaving a pub lock-in well after the doors of the renowned Lloyd’s Hotel (haunt of hydrologists at Llanidloes where he was staying) were locked, he and his fellow fieldworkers famously “borrowed” a ladder from a nearby builder’s yard to climb in via the back window! Then, in the course of his flights to India, he developed a legendary capacity for hoarding airline knick-knacks, usually disembarking with a store of acquired cans of tonic water to complement his bottle of locally purchased gin!

After a long illness borne with tremendous fortitude, Ian succumbed to Motor-Neurone
Disease in May 2009. He continued to work on his projects up to the final few days,
communicating by email when his voice failed. He is survived by his wife, Val, and their daughters, Fiona and Isabel.

James Bathurst, Jaime Amezaga, Richard Harding, Jennifer Harrison, Andy Large, Jim
McCulloch, Malcolm Newson, Enda O’Connell, Mark Robinson

心からご冥福を祈る。