Ecology of De-Glaciation

by

Kenneth R. Young

• LAST REVIEWED: 12 August 2022
• LAST MODIFIED: 27 July 2016
• DOI: 10.1093/obo/9780199830060-0156

Introduction

The retreat of glaciers provides ecological space for colonization by plants, animals, and microbes, in turn initiating primary ecological succession as substrates develop into soils. Ecological change following de-glaciation has reorganized biotic landscapes in the interglacial time periods of the Quaternary. Increasingly, it will become more important under current global climate change. As a result, the study of change following glacier recession is informed by studies on what happened in the past and by 21st-century research that accounts for glacial dynamics, including interactions of glacier mass balance with landscape and geoecological dynamism. There are important differences among the de-glaciated sites of high mountains and of places with large continental ice sheets. Ecological studies in these landscapes often use chronosequence approaches to evaluate successional change but also increasingly depend on experimental and modeling approaches to assess the roles of different processes. Research on the details of change reveals important roles for microbial-mediated processes, in addition to the more often studied colonization by plants and interactions with animals. In addition, there are important downstream consequences, connecting de-glaciation with further changes in stream, wetland, and watershed dynamics. Perhaps surprisingly, one result of de-glaciation is a rise in sea levels, with consequences worldwide. The ecology of de-glaciation will become increasingly important as future climate change may require sometimes controversial assisted migration strategies for conservation in high latitudes and high mountains. There are also many applications derived from the study of de-glaciation that would be useful for doing ecological restoration in degraded landscapes.

Ecological Succession

Primary succession takes place when soils must form as part of ecological succession. The study of change following de-glaciation must necessarily include soil-forming processes, in addition to the study of facilitation, tolerance, and inhibition processes that affect the sequence of events happening in a de-glaciated site. Some of the classic studies in ecological succession have been done in these kinds of environments. For example, compare the pioneering research of Cooper 1923 in Glacier Bay, Alaska, with the exhaustive follow-up research by Chapin, et al. 1994, which isolated the causal mechanisms at work. The best available source for theoretical concepts and their practical implications is Walker 2012. Advances in the study of disturbance ecology and its connections to ecological succession associated with plants are covered by Glenn-Lewin, et al. 1992, and illustrated with useful examples in Johnson and Miyanishi 2007. The plant adaptations to life in high mountains are discussed in detail in Körner 2003, with many implications for the functions of changing high elevation ecosystems. Reference books on ecosystem science include the useful perspectives in Weathers, et al. 2013, while Magurran and McGill 2011 provides easy access to the best current methods in assessing biodiversity and ecological change.

• Chapin, F. Stuart, III, Lawrence R. Walker, Christopher L. Fastie, and Lewis C. Sharman. 1994. Mechanisms of primary succession following deglaciation at Glacier Bay, Alaska. Ecological Monographs 64:149–175.

  DOI: 10.2307/2937039

  Life history traits of plants determine their role in primary succession in the Glacier Bay area of Alaska. Competition, facilitation, and initial conditions all affected ecosystem rate and vegetation patterns.

• Cooper, William Skinner. 1923. The recent ecological history of Glacier Bay, Alaska: II. The present vegetation cycle. Ecology 4:223–246.

  This is one of several in a series that describes the classic studies and observations made by Cooper in the Glacier Bay area of Alaska. This describes the current vegetation found in the area and elucidates ideas on how primary succession on rocks and moraines would proceed, in addition to expected changes in ponds.

• Glenn-Lewin, David C., Robert K. Peet, and Thomas T. Veblen, eds. 1992. Plant succession: Theory and prediction. London: Chapman & Hall.

  Seminal and readable source for ecological succession theory and ways to study ecological succession over a variety of time scales.

• Johnson, Edward A., and Kiyoko Miyanishi, eds. 2007. Plant disturbance ecology: The Process and the Response. Amsterdam: Elsevier.

  Edited collection that examines the role of wind, fire, and animal-mediated disturbances on vegetation, and the means of ecological recovery by plants.

• Körner, Christian. 2003. Alpine plant life: Functional plant ecology of high mountain ecosystems. 2d ed. Berlin: Springer.

  DOI: 10.1007/978-3-642-18970-8

  Well-illustrated review of the ecology and adaptations of plants found in high elevation mountains, along with discussions of ecosystem dynamics related to plants.

• Magurran, Anne E., and Brian J. McGill, eds. 2011. Biological diversity: Frontiers in measurement and assessment. Oxford: Oxford Univ. Press.

  Handy synthesis of the means, difficulties, and advantages of different strategies to measure spatial and temporal change in biodiversity. Covered topics include microbial ecology, disturbance, and functional traits.

• Walker, Lawrence R. 2012. The biology of disturbed habitats. Oxford: Oxford Univ. Press.

  Comprehensive survey of the causes of disturbance to habitats and the spatial and temporal patterns of post-disturbance recovery. Also contains important discussions of human-caused disturbances and the implications for management and ecological restoration.

• Weathers, Kathleen C., David L. Strayer, and Gene E. Likens. 2013. Fundamentals of ecosystem science. Amsterdam: Elsevier.

  Useful introduction to the energetics and biogeochemistry of ecosystems, with examples and applications of ecosystem science.