Joyce Lambert (born Herne Hill, London, 23 June 1916, died 4 May 2005), was an English botanist and stratigrapher. She showed that the Norfolk Broads are artificial when it had been thought that they were natural.
Lambert grew up at Brundall, Norfolk, and was educated at Norwich High School for Girls and the University College of Wales, Aberystwyth, graduating in botany in 1939.
Her first job was as a schoolteacher in Norwich, then in 1942 she was appointed a botany lecturer at the University of London's Westfield College (now part of Queen Mary, University of London). She began a study of the ecology of the Fens around the River Yare. In 1946, she began to publish academic papers on her work. In 1948, she moved to the University of Cambridge and concentrated on the Fens near the River Bure, working with J. N. Jennings.
In 1952, Jennings's book, The Origin Of The Broads, was published by the Royal Geographical Society. In it the stratigrapher concluded that most, if not all, of the Norfolk Broads had been formed by natural processes. But Jennings's apparently definitive interpretation was about to be spectacularly challenged. His colleague, botanist and fellow stratigrapher, Joyce Lambert, had also been investigating the Bure and Yare valley broads and fens.
Using a smaller peat borer than the one employed by Jennings, Lambert obtained a series of closely spaced cores around the broads, and discovered, to her amazement, that what had been thought to be natural lakes had near-perpendicular walls; moreover, their floors, some 3 m or so below the surface, were almost flat. Clearly, they had originated as peat diggings, whose angular shape had been concealed by the overgrowth of vegetation once they had filled up with water.
In 1952, Lambert gave the presidential address at the Norfolk and Norwich Naturalists' Society, and when editing that speech for publication, she inserted into it her new findings. These, together with a follow-up article in the Geographical Journal, caused a sensation by showing that the current features of the Norfolk Broads were created by extensive excavations dug by hand long ago, now within areas of flood plain subject to regular inundation, resulting in the typical Broads landscape of today, with its reed beds, grazing marshes and wet woodland.