Introduction: Historical Perspective and Significance of Alpine Ecosystem Studies

Alpine tundra is an intriguing ecosystem—for its beauty as well as for the harsh climate in which it exists. Contrasted against jagged rock precipices and snow and ice and subjected to rapid changes in weather, the tundra, with its proliferation of diminutive flowers, appears deceptively fragile. John Muir, in detailing the alpine of the Sierra Nevada, was at a loss to adequately describe “the exquisite beauty of these mountain carpets as they lie smoothly outspread in the savage wilderness” (Muir 1894). Despite this aesthetic fascination for the alpine, it is one of the least studied ecosystems in the world. Significant effort has been expended to describe the physiological ecology of alpine organisms (e.g., Bliss 1985; Carey 1993; Körner 1999) and community patterns (Komárková 1979; Billings 1988), but there have been no syntheses detailing alpine ecosystem processes and patterns to the degree that they have been described in the arctic (e.g., Chapin 1992) and forest (e.g., Likens and Bormann 1995) ecosystems. The goal of this book is to provide a description of the Niwot Ridge/Green Lakes Valley alpine ecosystem of the Front Range in the Colorado Rocky Mountains, including the spatial and temporal patterns of animals, plants, and microorganisms and the associated ecosystem processes. The book focuses on the strengths of the research carried out on Niwot Ridge during the past four decades, particularly physical factors influencing alpine ecology (climate and geomorphology), patterns and functions of the vegetation, and N biogeochemistry. While the book focuses on a particular site, the results can be extrapolated to much of the southern and central Rocky Mountains, and thus it pertains to a broader geographic and scientific scope and will be of direct interest to ecologists in general as well as to those interested in ecosystems in extreme environments. There are numerous justifications for a synthesis of alpine ecosystem studies. While alpine tundra occupies only about 3% of the global land surface (Körner 1995) and thus has little impact on atmosphere-biosphere exchange, its presence at the extreme climatic tolerance for many organisms and its presence on every continent make it a good “indicator” system for regional environmental change.