Matching Items (2)
Filtering by

Clear all filters

149135-Thumbnail Image.png
Description

Restoration of riverine ecosystems is often stated as a management objective for regulated rivers, and floods are one of the most effective tools for accomplishing restoration. The National Re- search Council (NRC 1992) argued that ecological restoration means re- turning "an ecosystem to a close approximation of its condition prior

Restoration of riverine ecosystems is often stated as a management objective for regulated rivers, and floods are one of the most effective tools for accomplishing restoration. The National Re- search Council (NRC 1992) argued that ecological restoration means re- turning "an ecosystem to a close approximation of its condition prior to disturbance" and that "restoring altered, damaged, O f destroyed lakes, rivers, and wetlands is a high-priority task." Effective restoration must be based on a clear definition of the value of riverine resources to society; on scientific studies that document ecosystem status and provide an understanding of ecosystem processes and resource interactions; on scientific studies that predict, mea- sure, and monitor the effectiveness of restoration techniques; and on engineering and economic studies that evaluate societal costs and benefits of restoration.

In the case of some large rivers, restoration is not a self-evident goal. Indeed, restoration may be impossible; a more feasible goal may be rehabilitation of some ecosystem components and processes in parts of the river (Gore and Shields 1995, Kondolfand Wilcock 1996, Stanford et al. 1996). In other cases, the appropriate decision may be to do nothing. The decision to manipulate ecosystem processes and components involves not only a scientific judgment that a restored or rehabilitated condition is achievable, but also a value judgment that this condition is more desirable than the status quo. These judgments involve prioritizing different river resources, and they should be based on extensive and continuing public debate.

In this article, we examine the appropriate role of science in determining whether or not to restore or rehabilitate the Colorado River in the Grand Canyon by summarizing studies carried out by numerous agencies, universities, and consulting firms since 1983. This reach of the Colorado extends 425 km between Glen Canyon Dam and Lake Mead reservoir (Figure 1). Efforts to manipulate ecosystem processes and components in the Grand Canyon have received widespread public attention, such as the 1996 controlled flood released from Glen Canyon Dam and the proposal to drain Lake Powell reservoir.

ContributorsSchmidt, John C. (Author) / Webb, Robert H. (Author) / Valdez, Richard A. (Author) / Marzolf, G. Richard (Author) / Stevens, Lawrence E. (Author)
Created1998-09
171645-Thumbnail Image.png
Description
The National Wilderness Preservation System (NWPS) is a collection of more than 800 areas designated as wilderness under the Wilderness Act of 1964. The Act defines wilderness as an “area where the earth and its community of life are untrammeled by man, where man himself is a visitor who does

The National Wilderness Preservation System (NWPS) is a collection of more than 800 areas designated as wilderness under the Wilderness Act of 1964. The Act defines wilderness as an “area where the earth and its community of life are untrammeled by man, where man himself is a visitor who does not remain.” Wilderness lands are supposed to be pristine examples of nature where the overseeing agency has not allowed any post-designation development. The language of the act describes land designated as wilderness as “untrammeled” by people, discounting thousands of years of human influence. It also discounts the potential effect of surrounding lands and visitors on the wilderness. The management of these lands falls to all four federal land management agencies, and they each had – and still have – their own organizational perspectives on the Wilderness Act and their agency’s role in its implementation. Although the Act provided criteria for designating and managing wilderness, concrete guidance is lacking. This ambiguity has allowed a rift to emerge between those who believe that wilderness should be actively managed and those who believe that wilderness should be preserved and left alone as much as possible. The diversity of views and agency approaches have created administrative divides between wilderness lands and other land types. In parallel, the introduction of subsequent environmental laws have placed additional legal boundaries on the land, creating parcels next to and within wilderness that are subject to different uses and requirements. This study, which marshals dozens of expert interviews and explores a series of wilderness cases across the United States, focuses on several unanticipated challenges of stewarding the NWPS in the 21st Century. These include: the impacts of public land parceling due to legal obligations; how statuary ossification affects current interpretations of the various laws bearing on wilderness lands; and ultimately how land managers and agencies – who are looking toward a future of increased anthropogenic impacts on wildlife biodiversity and endangered/threatened species on wilderness lands – approach these challenges.
ContributorsFacemire, Challie Renee (Author) / Minteer, Ben A (Thesis advisor) / Ellison, Karin (Thesis advisor) / Bradshaw, Karen (Committee member) / Hahn, Beth (Committee member) / Budruk, Megha (Committee member) / Arizona State University (Publisher)
Created2022