A DISTINGUISHED Lake District-based scientist who was an internationally renowned expert on micro-algae has died at his Ambleside home, aged 102.

Dr John Walter Guerrier Lund, who founded a research group at the Windermere laboratory of the Freshwater Biological Association, was born in Manchester in 1912. He attended Sedbergh School before studying at Manchester University.

He was attracted initially to zoology but changed to botany, obtaining the only first class honours of the 1934 year class, despite having no science education at school. In 1935, he moved to University College, London, to work on benthic algae under Professor F. E. Fritsch, then one of the country’s leading phycologists, and gained his PhD in 1939. He worked at the West Midlands Forensic Science Laboratory in Birmingham, for several years as a forensic botanist.

In1944, he joined the staff of The Freshwater Biological Association as an algologist and began his work on the ecology of planktonic algae of the English Lake District, initially at Wray Castle and then, from 1950, at the association’s premises, The Ferry House. He continued in this post until retiring as a deputy chief scientific officer in 1978. However, he continued to work several days a week at The Ferry House until 2005.

Dr Lund’s research work on the nature and activity of phytoplankton was always imaginative and thorough and extremely influential. He discovered, described and brought into laboratory culture, many new species of algae.

In the 1960s, he began a series of field experiments employing in-situ artificial enclosures of increasing size, realism and complexity.

During this time, he worked with a fellow scientist, Hilda Canter, whom he later married. Together, they studied the intriguing range of fungal parasites that infect algae, publishing a series of papers on their taxonomy and life-histories which have scarcely been emulated.

A feature of Dr Lund's work was the close working collaborations he formed with colleagues. He also encouraged a series of assistants and students to develop special interests and talents, in various specialisms. In doing so, he promoted the continuing ability of freshwater science to cultivate the good biological management of lakes, reservoirs and rivers that is so often threatened by ignorance and inexpert supposition.

Dr Lund travelled extensively, contributing at scientific meetings or advising on projects overseas. He learned to read and speak Russian, quite fluently and wrote at least one paper in Russian.

He was elected a Fellow - and was for a time chairman- of the Royal Society. In 1965, he was awarded the CBE. He was also a past president of the British Phycological Society.

His wife pre-deceased him.