Many reports depend on the opinion and judgment of both field personnel and authors rather than on current data.
The reports cited above attempted to combine these data into a national-level assessment of rangelands, but the results have been inconclusive. The debate is further clouded by disagreement within the scientific community over the utility of the current range condition SCS , ecological status USFS and BLM , and apparent trend assessment methods see Chapter 3.
The methods developed in the early s were designed to assess the suitability of rangelands for grazing. New methods were adopted after , but some ecologists now challenge the validity of those methods for assessing rangelands.
Even where representative surveys of rangelands have been conducted using current range condition SCS or ecological status USFS and BLM ratings, such as in the National Resources Inventory, the utility of the results as measures of the status of rangelands is now in question.
This disagreement and uncertainty concerning the state of the U. Public concern over the effect of livestock grazing on federal rangelands has intensified Royte, ; Shaw, ; Wuerthner, , leading to a variety of current efforts to restrict livestock grazing on federal lands.
The fact that available data do not allow investigators to reach definitive conclusions on the relative proportions of rangelands that are improving or degrading or on the relative rates of improvement or degradation seriously impedes efforts to resolve the debate over proper use and management of the nation's federal and nonfederal rangelands. The data that have been available for assessing the status of rangelands are obtained by many different methods and from many different sources.
Different experts who look at the same data have interpreted them differently, confusing both the public and rangeland professionals. There is an urgent need to develop the methods and data collection systems needed to determine whether rangelands are improving or degrading. The importance of the commodities and values provided by. Many wild animals graze on U. Here, elk graze in a California state park. Forest Service. All attempts at national-level assessments reveal that degradation, particularly that from wind and water erosion, occurs on a significant portion of the nation's rangelands.
The area of rangelands estimated to be deteriorating varies depending on the data that are used and how they are interpreted. The fact that it is impossible, with current methods and with current data, to determine whether federal and nonfederal rangelands are improving or degrading is itself a cause for concern.
Given the ecological and economic importance of U. Overgrazing by domestic or wild animals, inappropriate recreational uses, disease and insect outbreaks, drought, and other human-reduced or naturally occurring stresses can and do degrade rangelands.
Serious degradation can result in the irreversible loss of the capacity of rangelands to produce commodities and satisfy values and the loss of some or all options for using and managing rangelands in the future. Federal and nonfederal rangelands produce a diversity of tangible commodities and satisfy many societal values that are important to the U.
Overgrazing, harmful recreational uses, drought, and other human-induced or natural events have led to serious rangeland degradation in the past. Although the available data show that some rangelands continue to deteriorate, the full extent and the causes of that degradation are the subjects of debate.
Given the importance of rangelands and the potential for serious degradation from both mismanagement and natural events, it is essential that the responsible agencies marshal the resources needed to develop and implement the data collection systems needed to provide policymakers, ranchers, environmentalists, and the general public with more definitive information on the state of federal and nonfederal rangelands.
Rangelands comprise between 40 and 50 percent of all U. The health and management of rangelands have been matters for scientific inquiry and public debate since the s, when reports of widespread range degradation and livestock losses led to the first attempts to inventory and classify rangelands.
Scientists are now questioning the utility of current methods of rangeland classification and inventory, as well as the data available to determine whether rangelands are being degraded. These experts, who are using the same methods and data, have come to different conclusions. This book examines the scientific basis of methods used by federal agencies to inventory, classify, and monitor rangelands; it assesses the success of these methods; and it recommends improvements. The book's findings and recommendations are of interest to the public; scientists; ranchers; and local, state, and federal policymakers.
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Get This Book. Visit NAP. Looking for other ways to read this? No thanks. Prairie June grass Koelaria cristata. Page 19 Share Cite. Federal and nonfederal lands produced some ,, animal-unit months the amount of forage consumed by an animal unit, usually estimated at kilograms [ pounds], in 1 month of forage for beef cattle and sheep in ; federal lands produced 7 percent and non- FIGURE Pie charts show percent of total U.
Page 20 Share Cite. Human Interactions on Western U. Page 21 Share Cite. Page 22 Share Cite. Federal Management of U. Page 23 Share Cite. Page 24 Share Cite. Present State of Rangelands. Page 25 Share Cite. General Accounting Office, a , which was based on available data for riparian areas, reported that although some riparian areas were successfully restored, many thousands of kilometers of riparian habitat were in FIGURE Categorized by land use, the chart shows figures for percentage of land eroding, by sheet and rill erosion alone, at higher than soil loss tolerance levels.
Page 26 Share Cite. Page 27 Share Cite. Page 28 Share Cite. Latest publications from the e-library. Back to search What are rangelands and grassland and why are they important?
Some lessons include: Local communities have a good knowledge of natural resources and their state Local land degradation indicators are relevant to rangeland health assessment and they provide more detail than those of remote sensing GIS and remote sensing tools allow for large-scale extrapolation of field assessment results There is complementarity between the remote sensing and local field indicators methods, they can be integrated to develop a holistic tool for assessing rangelands There is a need to exclusively consider the role of vulnerable groups and women as stakeholders mapping exercise characterize the landscape and different scales micro and macro Herder-led landscape classification gives better categorization and understanding of scale If methodology is implemented across sites, a minimum set of indicators for cross-site comparison There is need to validate the draft DPSIR framework with the rangeland users.
Rangelands can include annual and perennial grasslands, shrub and dry woodlands, savannah, tundra, and desert. Grasslands on the other hand are lands on which the vegetation is dominated by grasses. What is the relationship of overgrazing to desertification?
Why would there be desert in North Africa? How can rangeland be degraded? How can rangeland be improved? How does overgrazing affect rangelands? How can we conserve rangelands? What are federal rangelands?
Why are public rangelands in poor condition?
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