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The McKenzie River is a tributary to the Willamette River in northwestern Oregon. The McKenzie River is approximately 90 miles in length and has a drainage area of approximately 1,300 square miles. Two major flood control dams, a hydropower dam complex, and two hydropower canals significantly alter streamflows in the river. The structures reduce the magnitude and frequency of large and small floods while increasing the annual 7-day minimum streamflows. Stream temperatures also have been altered by the dams and other anthropogenic factors, such as the removal of riparian vegetation and channel simplification. Flow releases from one of the flood control dams are cooler in the summer and warmer in the fall in comparison to unregulated flow conditions before the dam was constructed. In 2006, the Oregon Department of Environmental Quality listed a total of 112.4, 6.3, and 55.7 miles of the McKenzie River basin mainstem and tributary stream reaches as thermally impaired for salmonid rearing, salmonid spawning, and bull trout, respectively. The analyses in this report, along with previous studies, indicate that dams have altered downstream channel morphology and ecologic communities. In addition to reducing the magnitude and frequency of floods, dams have diminished sediment transport by trapping bed material. Other anthropogenic factors, such as bank stabilization, highway construction, and reductions of in-channel wood, also have contributed to the loss of riparian habitat. A comparison of aerial photography taken in 1939 and 2005 showed substantial decreases in secondary channels, gravel bars, and channel sinuosity, particularly along the lower alluvial reaches of the McKenzie River. In addition, bed armoring and incision may contribute to habitat degradation, although further study is needed to determine the extent of these processes. Peak streamflow reduction has led to vegetation colonization and stabilization of formerly active bar surfaces. The large flood control dams on Blue River and South Fork McKenzie River likely have had the greatest effect on downstream habitats because these sediment and flood-rich tributaries historically contributed a disproportionate volume of bed material, wood, and peak flows in comparison with the spring-fed tributaries of the upper McKenzie River basin. The ecological effects of the dams were examined by focusing on nine exemplar aquatic and terrestrial species, including spring Chinook salmon, bull trout, Oregon chub, Pacific and western brook lamprey, red-legged frog, western pond turtle, alder, and cottonwood. The changes caused by the dams to streamflow hydrograph affect all these and other species in complex ways, although a few commonalities are apparent. A loss of channel complexity in the McKenzie River basin, which is associated with the reduction in flood events and widespread channel stabilization, is the primary factor related to the observed population declines for all nine exemplar species. The dams also have caused direct ecological effects by blocking access to habitat, changing the amount and timing of available critical habitat, and changing water temperature during important seasons for different life stages.
No abstract available.
Scenarios are possible future states of the world that represent alternative plausible conditions under different assumptions. Often, scenarios are developed in a context relevant to stakeholders involved in their applications since the evaluation of scenario outcomes and implications can enhance decision-making activities. This paper reviews the state-of-the-art of scenario development and proposes a formal approach to scenario development in environmental decision-making. The discussion of current issues in scenario studies includes advantages and obstacles in utilizing a formal scenario development framework, and the different forms of uncertainty inherent in scenario development, as well as how they should be treated. An appendix for common scenario terminology has been attached for clarity. Major recommendations for future research in this area include proper consideration of uncertainty in scenario studies in particular in relation to stakeholder relevant information, construction of scenarios that are more diverse in nature, and sharing of information and resources among the scenario development research community. ?? 2008 Elsevier Ltd.
It is reported that in the spring of 1969 a high official of one of the oil companies was flying over the area of oil development in the vicinity of Prudhoe Bay. He is quoted as saying "If the American people could see what we are doing to their land here, they would want to abolish the use of the reciprocating engine." The last really large area of wilderness in the United States is the' Brooks Range and the Arctic Coastal Plain which stretches from that range to the Arctic Ocean. The proving of the exploratory oil wells which have been drilled on the coastal plain in the vicinity of Prudhoe Bay makes it virtually certain that this heretofore mostly unknown country will rapidly and vigorously be exposed to a variety of changes caused by the influx of men and their equipment. Even within the first four months of 1969 the whole aspect of the central part of the region has been importantly changed by the drilling programs of several large oil companies. So suddenly was this change brought about that no long-range plans have been developed either to soften the effect of such development on the natural environment or even to record the progress of these effects. Yet the absence of a plan provides an inadvertent potential advantage in that there has' been no history of increasingly firm Federal policy which, in other places, has often made it difficult to take newly conceived action in line with the increasing societal interest in environmental preservation. The lack of firm Federal policy provides here a unique opportunity for the application of new rules and investigative techniques aimed at minimizing the adverse effects on the environment while5.at the same time, not unduly hindering the development of the natural resources. But the speed with which the changes are being wrought makes it imperative that the principles applicable here to environmental protection or preservation, be enunciated immediately and that from these principles flow farsighted regulations which reflect the new interest in combining resource development with environmental protection. The present report constitutes a brief summary of the conditions existing in northern Alaska in the spring of 1969, presenting some inferences on the environmental changes which can be expected in the future and offering some specific steps which, if taken immediately and positively, could greatly ameliorate the adverse effects of rapid development in the absence of positive steps for environmental protection. In that regard, then, this report is ephemeral in character because the conditions in northern Alaska will surely change with great rapidity. Considering the"fragility and sensitivity of the ecosystems existing there, the changes can be both harsh and permanent. Therefore, whatever value lies in the recommendations made here., the results of their application will depend on the promptness of their consideration, amendment, and application. Whatever form the actions might take for minimizing the harm to the environment, the urgency of the matter can hardly be overestimated.
1. Engineering geologic maps in the United States may be one map prepared as part of a larger study of environmental geology, individual areal geologic maps containing additional engineering geologic data, or engineering geologic maps of single construction sites. 2. No systematic methodology for engineering geologic or environmental geologic maps has been developed. 3. Environmental geology studies combine the efforts of workers in a number of geologic fields to produce many maps of basic data, as well as various interpretative maps, only one of which may be an engineering geologic or foundation conditions map. Maps of many scales may be prepared for a single study, depending upon the geologic conditions, the main problems of the area, and the principal needs. 4. New technology, including computers and various types of aerial photography, is constantly being developed, and its use is being encouraged to increase the speed and efficiency of map preparation. 5. The use of engineering geologic and environmental geologic maps in the United States is constantly growing; such maps will continue to be made in increasing numbers.
During the 6-year negotiation of and adoption of the Convention on the Regulation of Antarctic Mineral Resources Activities on June 2, 1988, various countries have increased their attention to the possibility of exploitation of Antarctica's petroleum resources, which are covered by this treaty. However, there are no known petroleum resources in Antarctica, and scientific information is lacking to adequately assess any undiscovered resources or the possible environmental hazards to their development. Scientific research carried out in Antarctica since the International Geophysical Year (1957-1958) has provided a great deal of information on the geological framework of this ice-covered continent and its margin and has found general indications of the types of hazards that must be considered. Antarctica covers a vast area, and likely supergiant oil fields of the type to be exploited would be tiny (e.g., a few tens of kilometers across) in comparison. Any petroleum resources located in Antarctica will be found by applying the knowledge, techniques, and experience gained developing oil fields in other parts of the world and would, therefore, be other examples of general cases; in contrast, the Antarctic environment and its associated hazards must be considered unique.
A geographic information system (GIS)-based spatial modeling approach was developed to study environmental and land use impacts on the geographic distribution of wintering northern pintails (Arias acuta) in the Lower Mississippi River region. Pintails were fitted with backpack radio transmitter packages at Catahoula Lake, LA, in October 1992-1994 and located weekly through the following March. Pintail survey data were converted into a digital database in ARC/INFO GIS format and integrated with environmental GIS data through a customized modeling interface. The study verified the relationship between pintail distributions and major environmental factors and developed a conceptual relation model. Visualization-based spatial simulations were used to display the movement patterns of specific population groups under spatial and temporal constraints. The spatial modeling helped understand the seasonal movement patterns of pintails in relation to their habitat usage in Arkansas and southwestern Louisiana for wintering and interchange situations among population groups wintering in Texas and southeastern Louisiana. (C) 2000 Elsevier Science B.V.
A meeting between the U.S. Geological Survey (USGS) and its partners was held June 14-16, 2005, in Denver, CO, to discuss science issues and needs related to agricultural practices. The goals of the meeting were to learn about the (1) effects of agricultural practices on the environment and (2) tools for identifying and quantifying those effects. Achieving these goals required defining the environmental concerns, developing scientific actions to address assessment of environmental effects, and creating collaborations to identify future research requirements and technical gaps. Five areas of concern were discussed-emerging compounds; water availability; genetically modified organisms; effects of conservation practices on ecosystems; and data, methods, and tools for assessing effects of agricultural practices.
Fleas are common ectoparasites of vertebrates worldwide and vectors of many pathogens causing disease, such as sylvatic plague in prairie dog colonies. Development of fleas is regulated by environmental conditions, especially temperature and relative humidity. Development rates are typically slower at low temperatures and faster at high temperatures, which are bounded by lower and upper thresholds where development is reduced. Prairie dogs and their associated fleas (mostly Oropsylla spp) live in burrows that moderate outside environmental conditions, remaining cooler in summer and warmer in winter. We found burrow microclimates were characterized by stable daily temperatures and high relative humidity, with temperatures increasing from spring through summer. We previously showed temperature increases corresponded with increasing off-host flea abundance. To evaluate how changes in temperature could affect future prairie dog flea development and abundance, we used development rates of O. montana (a species related to prairie dog fleas), determined how prairie dog burrow microclimates are affected by ambient weather, and combined these results to develop a predictive model. Our model predicts burrow temperatures and flea development rates will increase during the twenty-first century, potentially leading to higher flea abundance and an increased probability of plague epizootics if Y. pestis is present.
NetCDF (Network Common Data Form) is a data sharing protocol and library that is commonly used in large-scale atmospheric and environmental data archiving and modeling. The NetCDF tool described here, named NCWin and coded with Borland C + + Builder, was built as a standard executable as well as a COM (component object model) for the Microsoft Windows environment. COM is a powerful technology that enhances the reuse of applications (as components). Environmental model developers from different modeling environments, such as Python, JAVA, VISUAL FORTRAN, VISUAL BASIC, VISUAL C + +, and DELPHI, can reuse NCWin in their models to read, write and visualize NetCDF data. Some Windows applications, such as ArcGIS and Microsoft PowerPoint, can also call NCWin within the application. NCWin has three major components: 1) The data conversion part is designed to convert binary raw data to and from NetCDF data. It can process six data types (unsigned char, signed char, short, int, float, double) and three spatial data formats (BIP, BIL, BSQ); 2) The visualization part is designed for displaying grid map series (playing forward or backward) with simple map legend, and displaying temporal trend curves for data on individual map pixels; and 3) The modeling interface is designed for environmental model development by which a set of integrated NetCDF functions is provided for processing NetCDF data. To demonstrate that the NCWin can easily extend the functions of some current GIS software and the Office applications, examples of calling NCWin within ArcGIS and MS PowerPoint for showing NetCDF map animations are given.
Environmental planners often rely on transportation structures (i.e., underpasses, bridges) to provide connectivity for animals across developed landscapes. Environmental assessments of predicted environmental impacts from proposed developments often rely on literature reviews or other indirect measures to establish the importance of wildlife crossings. Literature-based evaluations of wildlife crossings may not be accurate, and result in under-estimation of impacts or establishment of inappropriate mitigation measures. To investigate the adequacy of literature-based evaluations, we monitored wildlife use of a freeway underpass that had been identified as critically important to wildlife connectivity, and which was evaluated in an environmental review document. Photographs were obtained from a network of trail cameras over 3 years. Six mid- to large-sized native mammal species used the underpass and two other mammal species were photographed near the underpass but not using it. American badger ( Taxidea taxus ) was photographed at a higher rate in the underpass than in the surrounding area. Gray fox ( Urocyon cinereoargenteus ) was rarely detected in the underpass relative to surrounding habitats, whereas the absence of mule deer ( Odocoileus hemionus ) in the underpass was unexpected, given relatively frequent detection in adjacent habitats. These results differed from the environmental assessment in that American badger was listed as "potentially" present while mule deer were expected to use the underpass. Results underscore importance of gathering data to document wildlife use of corridors, because some species do not or rarely take advantage of apparently suitable corridors, while others may be present when assumed to be absent.
Development of shale gas and tight oil, or unconventional oil and gas (UOG), has dramatically increased domestic energy production in the U.S. UOG resources are typically developed through the use of hydraulic fracturing, which creates high-permeability flow paths into large volumes of tight rocks to provide a means for hydrocarbons to move to a wellbore. This process uses significant volumes of water, sand, and chemicals, raising concerns about risks to the environment and to human health. Researchers in various disciplines have been working to make UOG development more efficient, and to better understand the risks to air quality, water quality, landscapes, human health, and ecosystems. Risks to air include releases of methane, carbon dioxide, volatile organic compounds, and particulate matter. Water-resource risks include excessive withdrawals, stray gas in drinking-water aquifers, and surface spills of fluids or chemicals. Landscapes can be significantly altered by the infrastructure installed to support large drilling platforms and associated equipment. Exposure routes, fate and transport, and toxicology of chemicals used in the hydraulic fracturing process are poorly understood, as are the potential effects on terrestrial and aquatic ecosystems and human health. This is made all the more difficult by an adaptable and evolving industry that frequently changes methods and constantly introduces new chemicals. Geoscientists responding to questions about the risks of UOG should refer to recent, rigorous scientific research.
Indicators are routinely used to report the status and trends of human health, economy, educational achievement, and quality of life. Some environmental indicators, such as for water and air quality, are routinely reported and used to inform personal, management, or policy decisions. Other environmental indicators, particularly those that do not relate directly to human well-being, have been harder to define, interpret, or use. These indicators may be just as useful and important in describing the ability to provide ecosystem good and services, or less tangible quality of life measures, but they may be suspect because of the quality of data or even the source of the information.
In a recent article in "Science" discussing the Environmental Policy Act of 1969, Gillette (1971) states "The law's instructions for preparing an impact report apparently are not specific enough to insure that an agency will fully, or even usefully, examine the environmental effects of the projects it plans." This report contains a procedure that may assist in developing uniform environmental impact statements. The Department of the Interior and the Council on Environmental Quality will appreciate comments on the procedure here proposed. The heart of the system is a matrix which is general enough to be used as a reference checklist or a reminder of the full range of actions and impacts on the environment that may relate to proposed actions. The marked matrix also serves as an abstract of the text of the environmental assessment to enable the many reviewers of impact reports to determine quickly what are considered to be the significant impacts and their relative importance as evaluated by the originator of the impact report. Many exhaustive studies of the use of matrices for environmental studies are now being undertaken. (See Sorensen, 1971.) This comparatively simple system is intended as a guide for the many people who are faced with the evaluation and preparation of environmental impact reports before the results of these studies have been completed. It should be borne in mind that there is presently no uniformity in approach or agreement upon objectives in an impact analysis and this generalized matrix is a step in that direction. The procedure does not limit the development of detail in any specific aspect of the environment; a separate expanded matrix for any environmental aspect can easily be developed within the framework provided.
The development of solid-phase extraction (SPE) for environmental chemistry has progressed significantly over the last decade to include a number of new sorbents and new approaches to SPE. One SPE approach in particular, the SPE disk, has greatly reduced or eliminated the use of chlorinated solvents for the analysis of trace organic compounds. This article discusses the use and applicability of various SPE disks, including micro-sized disks, prior to gas chromatography-mass spectrometry for the analysis of trace organic compounds in water.