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Wilderness Is Dead: Whither Critical Zone Studies and Geomorphology in the Anthropocene?


DOI: 10.1016/j.ancene.2013.03.001

Wohl, Ellen. “Wilderness Is Dead: Whither Critical Zone Studies and Geomorphology in the Anthropocene?” Biochemical Pharmacology (2013): 1–12. Web.

p.1: Numerous studies document the extent and intensity of human appropriation of ecosystem services and the manipulation of Earth’s surface and fluxes of water, sediment and nutrients within the critical zone of surface and near-surface environments. These studies make it increasingly clear that wilderness is effectively gone. This paper explores the implications for critical zone studies and management from a geomorphic perspective. Geomorphologists possess knowledge of the long history of human alteration of the critical zone. This knowledge can be applied to characterizing: historical range of variability and reference conditions; fluxes of matter and energy; and integrity and sustainability of critical zone environments. Conceptual frameworks centered on connectivity, inequality, and thresholds or tipping points are particularly useful for such characterizations, as illustrated by a case study of beaver meadows in the Front Range of Colorado, USA. Specifically, for connectivity, inequality, and thresholds, geomorphologists can identify the existence and characteristics of these phenomena, quantify and predict changes resulting from past or future human manipulations, and recommend actions to restore desirable conditions or prevent development of undesirable conditions. I argue that we should by default assume that any particular landscape has had greater rather than lesser human manipulation through time. This history of manipulation continues to influence critical zone process and form, and geomorphologists can use knowledge of historical context in a forward-looking approach that emphasizes prediction and management. -- Highlighted apr 6, 2014

p.1: In this paper, I argue that in fact many of us mistake landscapes altered by humans in the past for wilderness that has never experienced substantial human inuences, and that this misperception hampers our ability to understand the intensity and extent human manipulation of Earth surfaces. By more fully comprehending the global implications of human manipulations during Anthropocene, we can more effectively design management protect and restore desired landscape and ecosystem qualities. -- Highlighted apr 6, 2014

p.2: Many of the overview studies cited above also quantify current magnitude and distribution of human alteration of natural uxes, rather than explicitly considering interactions between humans and landscapes or ecosystems. Geomorphologists increasingly focus on such interactions in the form of feedback loops between resource use, landscape stability, ecosystem processes, resource availability, and natural hazards (Chin et al., in press). -- Highlighted apr 6, 2014

p.3: Given the documented extent and intensity of human alteration the critical zone, a vital question now is how can geomorphologists most effectively respond to this state of affairs? More than one recently published paper notes the absence of a geomorphic perspective in discussions of global change and sustainability (e.g., Grimm and van der Pluijm, 2012; Knight and Harrison, 2012; Lane, 2013). Geomorphologists certainly have important contributions make to scholarly efforts to understand and predict diverse aspects of global change and sustainability, but thus far the community as a whole has not been very effective in communicating this to scholars in other disciplines or to society in general. -- Highlighted apr 6, 2014

p.3: Geomorphologists can particularly contribute to increasing awareness of human effects on the critical zone during past centuries. Geomorphologists can also identify how human-induced alterations in the critical zone propagate through ecosystems and human communities – that is, geomorphologists can contribute the recognition that landscapes are not static entities with simple or easily predictable responses to human manipulation, but are rather complex, nonlinear systems that commonly display unexpected responses to human alteration. -- Highlighted apr 6, 2014

p.3: Whatever approach is taken, HRV is difficult to quantify. There is the challenge of defining when humans began to intensively alter critical zone process and form. Process and form are complexly interrelated and change substantially through time and space in the absence of human activities, as well as in response to human activities. Ability to quantify the range of variability in individual parameters or entire ecosystems strongly depends on the length and completeness of proxy records, as well as scientific understanding of the operation of the unaltered ecosystem. Reliance on reference conditions in a contemporary, relatively unaltered ecosystem can be misleading because contemporary conditions reflect only a single state or limited portion of the HRV (SER, 2002). In other words, we cannot metaphorically point to some time prior to the development of agriculture or other intensive human activity and use information regarding ecosystem conditions from this time as a precise target for managing and restoring an ecosystem. -- Highlighted apr 6, 2014

p.4: Beyond the fact that the characteristics of connectivity critically influence process and form in the critical zone, the specifics of connectivity can be used to understand how past human manipulations have altered a particular landscape or ecosystem, and how future manipulations might be used to restore desired system traits. -- Highlighted apr 6, 2014

p.5: Because not all moments in time or spots on a landscape are of equal importance, effective understanding and management of critical zone environments requires knowledge of how, when, and where fluxes occur. Particularly dynamic portions of a landscape, such as riparian zones, may be disproportionately important in providing ecosystem services, for example, and relatively brief natural disturbances, such as floods, may be disproportionately important in ensuring reproductive success of fish populations. Recognition of inequalities also implies that concepts and process- response models based on average conditions should not be uncritically applied to all landscapes and ecosystems. -- Highlighted apr 6, 2014

p.6: Arguably the most difficult thresholds to identify, but also the most important, are those that define the limits of sustainability for a species, a biotic community, or a specific resource use by humans. As noted earlier, sustainability is most effectively defined within a specified time interval, but implies the ability to maintain existing conditions during that time interval. Thresholds associated with exceeding sustainability limits unfortunately seem to be most commonly identified once they have been crossed and a species has gone locally or globally extinct, a biotic community has disappeared locally or globally, or a human community can no longer use a resource such as agricultural soils that have eroded or become saline, fisheries that have collapsed, or ground or surface waters that are no longer potable. Clearly, there is an intellectual challenge in identifying these more complex thresholds before they are crossed, and meeting this challenge has the added substantial benefit of contributing to sustaining critical zone integrity. -- Highlighted apr 6, 2014

p.9: The default assumption of greater human impact means, among other things, that we must work to overcome our own changing baseline of perception. I use changing baseline of perception to refer to the assumption that whatever we are used to is normal or natural. A striking example comes from a survey administered to undergraduate science students in multiple U.S. states and several countries. In the survey, students were shown an identical series of photos of river segments and asked to rate each river segment on a numerical scale in terms of being natural, esthetically pleasing, dangerous, and needing improvement. With the exception of the U.S. state of Oregon, and the countries of Germany and Sweden, students consistently rated river segments containing instream wood negatively, viewing these river segments as unnatural, dangerous, and in need of rehabilitation (Chin et al., 2008). This completely contradicts the manner in which river scientists view instream wood, and ignores the logical assumption that, since a much greater proportion of the world was forested historically, most river segments in forested environments would naturally contain a great deal of instream wood (Montgomery et al., 2003). The students’ negative perception of instream wood at least partly reflects the fact that most of them are used to seeing rivers with very little instream wood, even in forested environments, because of historical and continuing wood removal. Wood-poor rivers now seem normal and natural to most people. Those of us who work in rivers and are familiar with the scientific literature on instream wood, as well as the idea of dramatic historical change in landscapes and ecosystems, can metaphorically step back and shake our heads at the students’ misperceptions, but identifying our own unexamined and misleading perceptions is much more challenging. -- Highlighted apr 6, 2014