Richard Battarbee Prof. Rick Battarbee Environmental Change Research Centre University College London UK If you would like to interview this scientist, please contact Leah Christen. > biographical information > abstract > paper

Biographical Information:

I have spent most of my research career trying to develop the use of diatoms as indicators of limnological change. I now head up a group of limnologists and paleolimnologists at the Environmental Change Research Centre in UCL, working on lakes of all types throughout the world. Before taking up my position in UCL, I completed a PhD with Frank Oldfield in the New University of Ulster (1968-1971) and a Royal Society Post-Doctoral Fellowship in the University of Uppsala (1971-1973). I also spent a year in the Limnological Research Center in the University of Minnesota with Herb Wright (1981-1982). In the UK, I have been most involved with surface water acidification research, chairing the national program on freshwaters. Internationally with PAGES, I have been the co-leader (with Francoise Gasse) of the PEPIII project, I am now coordinator of the Focus 5 program LIMPACS and serve on the PAGES Scientific Steering Committee and EXCOM. I am also chair of the European Science Foundation program on Holocene Climate Variability (HOLIVAR) that concludes in 2006.

Lake ecosystem research in PAGES is coordinated by the LIMPACS program. For more information visit: www.geog.ucl.ac.uk/ecrc/limpacs.

Abstract:

Paleolimnology, pollution and climate change

Lakes are highly distinctive features of the earth’s surface. They vary greatly in distribution, size, age, origin, chemistry, biology and in the extent of their alteration by human activity. Lakes close to human settlements, receiving waste-water and run-off from agricultural land, have been very heavily modified by the effects of eutrophication, others with low natural alkalinity close to industrial areas have suffered from acidification, and in many arid and semi-arid regions of the world abstraction of fresh-water for drinking and irrigation has caused severe salinization. Even in the most remote regions that are relatively free from these pressures it is possible to detect the presence of long-range transported air pollutants that accumulate in the food chain. And all lakes are now exposed to additional threats from greenhouse-gas forced climate change acting both directly in terms of changing temperature, precipitation and wind regimes and indirectly through the influence of climate change on catchment land-use and on the behavior of pollutants.

Understanding how these pressures combine and interact to change the structure and functioning of lake ecosystems on different time-scales is a central focus of limnological research requiring the combined expertise of both neo-limnologists, paleolimnologists and lake modellers. Here I am concerned principally with the role of paleolimnology. I will explain how lake sediment records can be used to reconstruct changes in lake status through time and how such records can potentially be combined to provide unique insights into regional and global patterns of environmental change. In particular, I will stress the role of lakes and lake-sediment records in remote regions, and consider whether recently observed changes in remote sites are due to global warming or to other factors.

Paper:

Paleolimnology, pollution and climate change

Lakes, their use and misuse
Lakes are highly distinctive features of the Earth’s surface. They vary greatly in distribution, size, age, origin, chemistry, biology and naturalness. In addition, they are of great value as attractive features in the landscape and as a resource for human use in terms of water supply, amenity and recreation. They are also centers of biodiversity and excellent indicators of local, regional and global environmental change. However, almost all lake ecosystems are threatened by human activity, either by pollution, introduced species, changing catchment land-use or, more generally, through global warming.

For example, lakes close to human settlements, receiving waste-water and run-off from agricultural land, have been very heavily modified by the effects of nutrient enrichment (eutrophication), others with low natural buffering capacity close to industrial areas have suffered from acidification. Moreover, in many arid and semi-arid regions of the world, abstraction of fresh-water for drinking and irrigation has caused severe salinization. Even in the most remote regions of the world that are relatively free from these pressures it is possible to detect the presence of long-range transported air pollutants, such as DDT and PCBs.

Lakes and climate change
In some cases, especially in developed countries, there have been impressive attempts to restore lake systems. For example, nutrient loading has been successfully reduced to combat eutrophication problems and sulfur dioxide emissions from power stations have been reduced to combat acidification problems caused by acid rain. But even the success of such restoration efforts are threatened by the newer problem of climate change that will have an impact on lakes of all types, not only directly in terms of changing temperature, precipitation and wind regimes but also indirectly through the influence of climate change on catchment land-use and on the behavior of pollutants.

Lake sediments as recorders of global environmental change
Understanding how these pressures combine and interact to change lake ecosystems on different time-scales is a central focus of lake research. In this presentation I will describe the key environmental problems facing lake ecosystems and explain how lake sediments can be used to identify how and why lakes of different kinds have been altered by these pressures. I will also more generally show how sediment records from individual lakes can be combined to provide unique insights into regional and global patterns of environmental change. In particular, I will stress the role of lakes and lake sediment records in remote regions, and consider whether recently observed changes in such regions are due to global warming or to other factors.

Figure 1. Lochnagar, a high mountain lake in Scotland.

Figure 2. Coring on Luguna di Cimera in the Gredos Mountains in Central Spain