Mountain waters as witnesses of global pollution

Catalan J., Bartrons M., Camarero L., Grimalt J.O. (2013) Mountain waters as witnesses of global pollution. Living with Water: Targeting Quality in a Dynamic World. : 31-67.
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Doi: 10.1007/978-1-4614-3752-9_2

Resum:

Mountains lakes, streams, and rivers, collectively known as headwaters, are popularly seen as waters of the highest quality. However, human-related pollution has reached remote areas of the planet everywhere through atmospheric transportation. Mountain freshwater ecosystems are extreme environments for life and thus are particularly sensitive to some new stressors. This chapter begins by summarizing the main features of mountain freshwater ecosystems and then comments on the effects they have historically suffered. It focuses particularly on two environmental problems: (1) acidification and (2) contamination with persistent organic pollutants. These problems are at different stages of development and knowledge. Acidification mechanisms are well understood, and mitigation actions have been applied successfully. The pace of recovery and interaction with climate change are now focusing research interests. In contrast, the environmental problem of persistent organic pollutants in mountain waters has been unveiled only recently. Some initially unexpected findings, such as the increasing concentration of some pollutants with altitude, have stirred further investigations on bioaccumulation processes, which are summarized here. Actions against contamination of sites far from the pollution sources, such as mountains, require the development of international protocols. The fight against acidification constitutes a successful example of such actions, and efforts against other atmospheric pollutants are following suit. These large-scale actions require adequate long-term monitoring networks, models for interpretating the results, and sound understanding of the mechanisms that underlie the observed patterns. Research may focus on: (1) increasing understanding of biotransformation of organic pollutants in natural conditions; (2) better evaluation of toxicological effects on both organisms and ecosystems as a whole; and (3) the ways that climate change influences the transport, accumulation, and toxicity of pollutants, a subject that cuts across all freshwater quality issues. © 2013 Springer Science+Business Media New York. All rights are reserved.

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Global change revealed by palaeolimnological records from remote lakes: A review

Catalan J., Pla-Rabes S., Wolfe A.P., Smol J.P., Ruhland K.M., Anderson N.J., Kopacek J., Stuchlik E., Schmidt R., Koinig K.A., Camarero L., Flower R.J., Heiri O., Kamenik C., Korhola A., Leavitt P.R., Psenner R., Renberg I. (2013) Global change revealed by palaeolimnological records from remote lakes: A review. Journal of Paleolimnology. 49: 513-535.
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Doi: 10.1007/s10933-013-9681-2

Resum:

Over recent decades, palaeolimnological records from remote sites have provided convincing evidence for the onset and development of several facets of global environmental change. Remote lakes, defined here as those occurring in high latitude or high altitude regions, have the advantage of not being overprinted by local anthropogenic processes. As such, many of these sites record broad-scale environmental changes, frequently driven by regime shifts in the Earth system. Here, we review a selection of studies from North America and Europe and discuss their broader implications. The history of investigation has evolved synchronously with the scope and awareness of environmental problems. An initial focus on acid deposition switched to metal and other types of pollutants, then climate change and eventually to atmospheric deposition-fertilising effects. However, none of these topics is independent of the other, and all of them affect ecosystem function and biodiversity in profound ways. Currently, remote lake palaeolimnology is developing unique datasets for each region investigated that benchmark current trends with respect to past, purely natural variability in lake systems. Fostering conceptual and methodological bridges with other environmental disciplines will upturn contribution of remote lake palaeolimnology in solving existing and emerging questions in global change science and planetary stewardship. © 2013 Springer Science+Business Media Dordrecht.

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