Frederick Blackman


Frederick Frost Blackman FRS was a British plant physiologist.
Frederick Blackman was born in Lambeth, London to a doctor. He studied medicine at St. Bartholomew's Hospital, graduating MA. In the subsequent years, he studied natural sciences at the University of Cambridge and was awarded DSc.
He conducted research on plant physiology, in particular photosynthesis, in Cambridge until his retirement in 1936. Gabrielle Matthaei was his assistant until 1905. He was elected in May 1906 a Fellow of the Royal Society, his candidature citation reading "Fellow of St John's College, Cambridge. Ex-Lecturer and now Reader in Botany in the University." He has made distinguished investigations in plant physiology. In 1921 he was awarded the Royal Medal and in 1923 delivered the Croonian lecture.
He was buried at the Parish of the Ascension Burial Ground in Cambridge, with his wife Elsie.

Blackman's law of limiting factors

Blackman proposed the law of limiting factors in 1905. According to this law, when a process depends on a number of factors, its rate is limited by the pace of the slowest factor. Blackman's law is illustrated by C O2 concentration as a limiting factor in the rate of oxygen production in photosynthesis:
Suppose a leaf is exposed to a certain light intensity which can use 5 mg. of C O2 per hour in photosynthesis. If only 1 mg. of C O2 enters the leaf in an hour, the rate of photosynthesis is limited due to C O2 factor. But as the concentration of the C O2 increases from 1 to 5 mg./hour the rate of photosynthesis is also increased.

Works

"Experimental researches in vegetable assimilation and respiration":