Windermere is perhaps the most comprehensively studied of any lake in the United Kingdom. It has been investigated by botanists, zoologists, chemists, hydrologists and palaeolimnologists for nearly a hundred years. Datasets covering more than 50 years now provide invaluable baselines for many of today's studies on environmental changes. The scientific methods that have been applied to the collection and measurement of these data have been both rigorous and well described, adding substantially to the value of the long time-series of accumulated information.
This book is a clear exposition of the lake's recent history and biology and aims to provide a factual guide to almost a century's work on the microscopic plant life of Windermere, its phytoplankton. Introductory sections briefly summarise major physical-chemical features of the lake and its catchment, and consider the effects of the light and temperature regime of the lake on algal physiology. Section 4 then outlines the development of the sampling programme on Windermere, although this is not intended to be a strictly historical account; the plankton is the primary focus. Section 5 takes as its baseline the last detailed summary of the phytoplankton ecology of Windermere, in 1965, which, as it will be shown, proved to be a crucial year in the development of the lake. Shortly after this, Windermere began to receive direct discharges of mineralised, secondary-treated sewage, accelerating delivery of important, biologically active components (nutrients) in the soluble form that is most readily taken up by phytoplankton. The consequences for planktic production in Windermere are the subject of Section 6. The decision to correct the adverse effects of direct nutrient enrichment of the lake, through the application of (tertiary) treatment to cut the loadings of soluble phosphate to the lake, and the programme of ecological restoration, are traced in Section 7. This also summarises the responses of the phytoplankton during the last decade of the 20th century.
Sections 8 and 9 consider investigations on mechanisms governing the physiological ecology of phytoplankton in Windermere, with particular emphasis on the role of environmental variability in influencing population responses in the phytoplankton. Finally, in Section 10, the scale of focus is raised to consider longer-term climatic cycles as revealed through palaeolimnological reconstructions of past plankton activity and the kinds of responses that might be anticipated as a consequence of global climatic changes.