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We revised distribution maps of potential presettlement habitat and current populations for Greater Sage-Grouse (Centrocercus urophasianus) and Gunnison Sage-Grouse (C. minimus) in North America. The revised map of potential presettlement habitat included some areas omitted from previously published maps such as the San Luis Valley of Colorado and Jackson area of Wyoming. Areas excluded from the revised maps were those dominated by barren, alpine, and forest habitats. The resulting presettlement distribution of potential habitat for Greater Sage-Grouse encompassed 1 200 483 km(2), With the species' current range 668 412 km(2). The distribution of potential Gunnison Sage-Grouse habitat encompassed 46 521 km(2), with...
Distributional patterns and species diversity of benthic insects in an alpine stream in Gunnison County, Colorado, USA were investigated on several levels of spatial scale, from faunal replacement over 1,000 vertical m to microdistribution within the stony substratum. Ecotones including zonation in terrestrial vegetation and in trout distribution did not appear to affect faunal replacement. Competition among congeners accounted for 7-30% of the cases, while in the majority of species, faunal replacement appeared to be associated with gradual changes in the physical gradient. Trout zonation may affect total numbers of insects, however, as the trout-free headwaters had two to six times higher insect densities. Microdistribution...
Aim: Greater sage-grouse (Centrocercus urophasianus), a shrub-steppe obligate species of western North America, currently occupies only half its historical range. Here we examine how broad-scale, long-term trends in landscape condition have affected range contraction. Location: Sagebrush biome of the western USA. Methods: Logistic regression was used to assess persistence and extirpation of greater sage-grouse range based on landscape conditions measured by human population (density and population change), vegetation (percentage of sagebrush habitat), roads (density of and distance to roads), agriculture (cropland, farmland and cattle density), climate (number of severe and extreme droughts) and range periphery....
The current distribution and status of populations of the southwestern toad, Bufo microscaphus, are of considerable interest given the suspected decline in anuran amphibians in the western United States (Blaustein and Wake 1990, Sweet 1991). This bufonid, typically associated with riparian habitats in the desert Southwest, is largely absent from much of its former range in southern California (Sweet personal communication). In Arizona and Utah, B. microscaphus is known to hybridize with a closely related toad, B. woodhousii, and it appears that B. woodhousii has replaced B. microscaphus at a number of localities (Sullivan 1986). Given the interest in this species and the lack of information on populations in Arizona,...
Information about geographic distributions is required for species conservation and management. Ultimately, this information is derived from records of occurrence. However, the reliability and availability of occurrence records are variable. A conceptual framework for evaluating the reliability of occurrence records is provided. Only records associated with physical evidence, especially a museum voucher specimen, are considered verified. However, errors in species identification or location are possible even for verified records. In addition, biases exist in occurrence records because they generally are collected haphazardly. Other sources of bias include sampling error associated with small areas or range limits...
Pelagic fish communities (waters with depths >20 m) of Lakes Powell and Mead were examined quarterly from 1995 to1998 using vertical gill nets and a scientific echosounder. Nets captured a total of 449 fish consisting of striped bass (57%/45% [Lake Powell/Lake Mead]), threadfin shad (24%/50%), common carp (15%/4%), walleye (3%), channel catfish (2%), and rainbow trout (<1%). Each reservoir contained concentrations of pelagic species separated by expanses of habitat with few fish (<10 kg ? ha?1). Reservoirs experienced dramatic seasonal and annual fluctuations in pelagic biomass. Lake Powell?s biomass peaked at the Colorado River at 709.7 (�46.5) kg ? ha?1 and Lake Mead?s reached 291.9 (�58.2) kg ? ha?1 at Las Vegas...
Social effects of building and operating nuclear power plants result from impacts upon (1) socially-valued aspects of the physical environment and (2) the social structure itself. Sudden, temporary population growth during construction may strain financial and organizational resources of rural areas. Large increases in tax base result from operation of privately-owned power plants, affecting tax structures and land use balances in site-specific fashion. Assessment of impacts involves dimensioning with fourteen descriptors, and analysis of impact recipient groups. Dissociation of social costs and benefits may occur (1) through time-lag between costs and benefits, (2) when different groups are beneficiaries and payees,...
The Southern Appalachian forest region of the U.S.-a region responsible for 23% of U.S. coal production-has 24 billion metric tons of high quality coal remaining of which mountaintop coal mining (MCM) will be the primary extraction method. Here we consider greenhouse gas emissions associated with MCM terrestrial disturbance in the life-cycle of coal energy production. We estimate disturbed forest carbon, including terrestrial soil and nonsoil carbon using published U.S. Environmental Protection Agency data of the forest floor removed and U.S. Department of Agriculture - Forest Service inventory data. We estimate the amount of previously buried geogenic organic carbon brought to the soil surface during MCM using...
The Southern Appalachian forest region of the U.S.-a region responsible for 23% of U.S. coal production-has 24 billion metric tons of high quality coal remaining of which mountaintop coal mining (MCM) will be the primary extraction method. Here we consider greenhouse gas emissions associated with MCM terrestrial disturbance in the life-cycle of coal energy production. We estimate disturbed forest carbon, including terrestrial soil and nonsoil carbon using published U.S. Environmental Protection Agency data of the forest floor removed and U.S. Department of Agriculture - Forest Service inventory data. We estimate the amount of previously buried geogenic organic carbon brought to the soil surface during MCM using...
Social effects of building and operating nuclear power plants result from impacts upon (1) socially-valued aspects of the physical environment and (2) the social structure itself. Sudden, temporary population growth during construction may strain financial and organizational resources of rural areas. Large increases in tax base result from operation of privately-owned power plants, affecting tax structures and land use balances in site-specific fashion. Assessment of impacts involves dimensioning with fourteen descriptors, and analysis of impact recipient groups. Dissociation of social costs and benefits may occur (1) through time-lag between costs and benefits, (2) when different groups are beneficiaries and payees,...
Social effects of building and operating nuclear power plants result from impacts upon (1) socially-valued aspects of the physical environment and (2) the social structure itself. Sudden, temporary population growth during construction may strain financial and organizational resources of rural areas. Large increases in tax base result from operation of privately-owned power plants, affecting tax structures and land use balances in site-specific fashion. Assessment of impacts involves dimensioning with fourteen descriptors, and analysis of impact recipient groups. Dissociation of social costs and benefits may occur (1) through time-lag between costs and benefits, (2) when different groups are beneficiaries and payees,...
This exploratory case study examines the social, economic, and political/institutional impacts of two operating nuclear power complexes on two New England communities. This work is one of a series planned to broaden knowledge of the effects of large energy generating facilities upon the social structure of local communities. Its primary objectives are to investigate and assess social and economic impacts resulting from construction and operation of nuclear power plants and to generate hypotheses about such impacts for future testing. The report includes discussions of the study design and objectives, profiles of the towns of Plymouth, Massachusetts, and Waterford, Connecticut, and analysis of the social, economic,...
Field surveys were conducted during 1997 and 1998 documenting the distribution and abundance of Colorado River cutthroat trout (Oncorhynchus clarki pleuriticus) in Escalante River tributaries. This documented occurrence of native trout in the Escalante River drainage of southern Utah represents an expansion of the known historic range of this subspecies as reported before the 1990s. We found 5 populations of native trout ranging in biomass from 3.0 to 104.2 kg ha-1 and occupying 13.2 km of stream of 130 km of estimated historic habitat. Current distribution and abundance of Colorado River cutthroat trout were compared to early introductions of nonnative trout stocked for sport fishing purposes. Native cutthroat...
This article provides a comprehensive and succinct review of the essentials needed to deal with the disputes encountered in the international energy sector. It begins with explaining the reasons why this sector has more disputes than any other business sector and then discusses how parties can effectively manage that risk. The article covers the kinds of disputes found in the international O&G business, the types of dispute resolution mechanisms available along with their respective advantages, and the legal framework for international arbitration. It explains how to properly draft dispute resolution clauses and what to consider in selecting counsel and in appointing arbitrators. A section is included that specifically...
This paper formulates an input-output method for determining the distributional consequences of energy development projects. The method is oriented to the conditions appearing in many contemporary development settings where large resident populations and other factors are likely to inhibit boomtown scenarios. An analysis of geothermal energy development in Imperial County, California, is presented. The results indicate that personal income inequality is likely to increase by several percentage points as measured by the Gini coefficient. The sensitivity of the results is examined with respect to important factors such as labor supply elasticities, preferential employment of local residents, and the concentration...
The Southern Appalachian forest region of the U.S.-a region responsible for 23% of U.S. coal production-has 24 billion metric tons of high quality coal remaining of which mountaintop coal mining (MCM) will be the primary extraction method. Here we consider greenhouse gas emissions associated with MCM terrestrial disturbance in the life-cycle of coal energy production. We estimate disturbed forest carbon, including terrestrial soil and nonsoil carbon using published U.S. Environmental Protection Agency data of the forest floor removed and U.S. Department of Agriculture - Forest Service inventory data. We estimate the amount of previously buried geogenic organic carbon brought to the soil surface during MCM using...
This article provides a comprehensive and succinct review of the essentials needed to deal with the disputes encountered in the international energy sector. It begins with explaining the reasons why this sector has more disputes than any other business sector and then discusses how parties can effectively manage that risk. The article covers the kinds of disputes found in the international O&G business, the types of dispute resolution mechanisms available along with their respective advantages, and the legal framework for international arbitration. It explains how to properly draft dispute resolution clauses and what to consider in selecting counsel and in appointing arbitrators. A section is included that specifically...
Past research has suggested that during the calving period, caribou (Rangifer tarandus) in Arctic Alaska generally avoid areas within 1 km of oilfield roads with traffic. However, avoidance is not absolute, and caribou may habituate to infrastructure (e.g., buildings, roads, well pads) and human activity. We conducted road-based surveys of caribou in oilfields on Alaska’s Arctic Coastal Plain during the late calving and post-calving periods of June in 2000– 02. We recorded location, composition, and behavior of caribou groups located less than 1 km from active gravel roads and production pads. Caribou groups with calves were on average distributed farther from oilfield infrastructure than were groups without calves,...
Biofuels world production has increased sharply in recent years. Oil reserves depletion, the oil high price and the confidence in biofuels “carbon neutrality” are the main causes of this phenomenon. However, claims related to the negative consequences of biofuel programs are frequent; mainly those related to the biofuels/food competition and sustainability. This paper aims to contribute for the development of a framework for sustainability indicators as a tool for performance assessment. The most used indicators to measure the biofuels sustainability are: Life Cycle Energy Balance (LCEB), quantity of fossil energy substituted per hectare, co-product energy allocation, life cycle carbon balance and changes in soil...
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