Dr. Farquhar has developed process-based models of photosynthesis, enabling the prediction of the environmental responses of carbon dioxide exchange between vegetation and the atmosphere, as well as models for the fractionation of the stable isotopes of carbon and oxygen during photosynthesis and transpiration. Doing so, he has made major contributions to the advancement of environmental and climate change sciences.
Photosynthesis by plants provides the foundational support to all ecosystems on Earth. Functional understanding of photosynthesis is thus critically important for analyzing responses of agricultural production and ecosystem processes to environmental changes. Terrestrial plants control stomata in order to optimize the uptake of carbon dioxide (CO2) from the atmosphere while preventing excessive water loss via transpiration. Hence, the assimilation rate of CO2 cannot be considered separately from transpiration.
Dr. Graham Farquhar and colleagues developed a series of process models of photosynthesis based on the fact that the carbon assimilation catalyzed by Rubisco is a major rate-limiting step in photosynthesis. The model first published in 1980 enabled quantitative analyses of CO2 exchanges between plants and the atmosphere in relation to multiple environmental factors, and applied to a wide range of biological levels from cells and leaves, to forests. The model has been used in quantitative evaluations of how diverse vegetations, such as agricultural fields, grasslands, and forests respond to increases of atmospheric CO2 due to human activities, and how these responses are affected by water availability and temperature. Most importantly, it is incorporated in almost all of the existing models of the terrestrial biosphere carbon cycles, and as such, it is indispensable for climate change science.
Dr. Farquhar also developed process-based models for fractionation of stable isotopes of carbon and oxygen during photosynthesis and transpiration by terrestrial plants. These models have been used extensively in botany, agricultural science, environmental science, paleontology (tree ring analysis), and ecosystem ecology (isotopic analysis of the food chain). Dr. Farquhar continues to be actively engaged in pioneering research in botany and environmental science. As for his contribution to agricultural sciences, Dr. Farquhar assisted selections of drought-resistant varieties of wheat and peanut by utilizing his process-based models of photosynthesis, which led to the identification of key genes for efficient water use.
Dr. Farquhar has actively contributed to climate change science and development of science-based policies, for example as a member of the Intergovernmental Panel on Climate Change, and also as a scientific advisor and an Australian representative to the Kyoto Protocol negotiations.
In summary, for almost 40 years, Dr. Farquhar has contributed to the advancement of environmental science and climate change science. As climate change science becomes increasingly important, his process-based models of photosynthesis will continue to play a significant role at the global research fronts.
For these reasons, the Inamori Foundation is pleased to present the 2017 Kyoto Prize in Basic Sciences to Dr. Graham Farquhar.
Ever since I was a young teenager I told people that I wanted to be a biophysicist. It was partly the desire to appear different, partly to appear more mature than I really was, but partly also to experience a newly developing field. It turned out that the arbitrary interest grew into something I love, but not without distractions along the way. Attending three different universities before I started my Ph.D. was one such distraction, but depending on one’s viewpoint, so too, perhaps, was learning ballet from the same time I started the Ph.D. The parallels between dance and science are strong, with heavy accent on mastery of technique, the similar roles of choreographer and laboratory head, and the somewhat magical intrusion of creativity. In practice I found that dance helped my science, forcing me to organize my time efficiently, making me fitter, buoying me when the experiments dragged me down, and fostering admiration for imaginative projects done skillfully. Of course it also extended my social life and led to some firm friendships. I stopped dancing when I was forty and moved to a rural block of 18 hectares, with kangaroos, echidnas, wombats and other distractions. We raised three children, which was enormously rewarding. All this time I had thought variously about photosynthesis and plant water relations, ecology and evolution, aspects of economics and optimal control theory and some labelled me as a dilettante. However it all fitted together in thinking about whether land plants exchanged water for carbon dioxide economically. What is economical for a rich person to do with their money is not the same as what is economical for a poor person to do, and the same is true of plants, plentiful water supply corresponding to riches. We spent a lot of time thinking about how to identify plants that are either more adventurous or more conservative. It turns out that this identification can be achieved by measuring the tiny differences in abundance of the heavier stable isotope of carbon in a leaf compared to that in carbon dioxide in the air. Marvellous! Whether viewed as a zig-zag of coincidences, or as the result of forethought, my science has been an enormous source of pleasure, and I would not have missed it for anything.