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Energy autarky is presented as a conceptual framework for implementing sustainable regional development based on the transformation of the energy subsystem. It is conceptualized as a situation in which the energy services used for sustaining local consumption, local production and the export of goods and services are derived from locally renewable energy resources. Technically, the implementation of higher degrees of energy autarky rests on increasing energy efficiency, realizing the potential of renewable energy resources and relying on a decentralized energy system. Practically, a transition towards regional energy autarky requires administrations and civil society actors to initialize and develop projects at...
The primary supposition about renewable forms of energy is that use of such resources will not result in depletion or exhaustion. While it is true that natural energy flows such as sun and wind are not directly subject to degradation by use, there may still be indirect limitations on renewability. The exploitation of natural energy flows may require that systems of nonrenewable "support" resources be used to capture, store, and convert natural energy into useful forms. Poor resource management practices that degrade the support resources may therefore, in effect, endanger renewability. Biomass is an illustrative case of a renewable energy resource with nonrenewable support components. The soil and water management...
The primary supposition about renewable forms of energy is that use of such resources will not result in depletion or exhaustion. While it is true that natural energy flows such as sun and wind are not directly subject to degradation by use, there may still be indirect limitations on renewability. The exploitation of natural energy flows may require that systems of nonrenewable "support" resources be used to capture, store, and convert natural energy into useful forms. Poor resource management practices that degrade the support resources may therefore, in effect, endanger renewability. Biomass is an illustrative case of a renewable energy resource with nonrenewable support components. The soil and water management...
Joseph A. Dammel, Jeffrey M. Bielicki, Melisa F. Pollak, and Elizabeth J. Wilson at the University of Minnesota Center for Science, Technology, and Public Policy have published a feature article titled “A Tale of Two Technologies: Hydraulic Fracturing and Geologic Carbon Sequestration” that appears in the online version of the science journal, Environmental Science & Technology [subscription required]. In comparing, contrasting, and analyzing the regulatory landscape governing the use of hydraulic fracturing and geologic carbon sequestration, they conclude that “A shift toward a 21st Century vision of regulation is required. Hydraulic fracturing and geologic sequestration are both technologies that could reduce...
Categories: Publication; Types: Citation; Tags: coal, dynamics, investment, model, system
Cheatgrass (Bromus tectorum L.) has come to dominate millions of hectares of rangeland in the Intermountain western United States. Previous studies have hypothesized that one mechanism conferring a competitive advantage to this species is the ability to germinate rapidly at low temperatures in the fall, winter and spring and, therefore, initiate growth and establishment more rapidly than more desirable perennial bunchgrass species. In this experiment, we developed thermal-germination-response models for multiple seedlots of cheatgrass and five perennial grass species. We conducted sensitivity analysis on potential-cumulative-germination response to a 38-year simulation of field-variable conditions of seedbed temperature...
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Natural landscapes in the Southwestern United States are changing. In recent decades, rising temperatures and drought have led to drier conditions, contributed to large-scale ecological impacts, and affected many plant and animal species across the region. The current and future trajectory of climate change underscores the need for managers and conservation professionals to understand the impacts of these patterns on natural resources. In this regional assessment of the Southwest Climate Change Initiative, we evaluate changes in annual average temperatures from 1951–2006 across major habitats and large watersheds and compare these changes to the number of species of conservation concern that are found within these...
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Final Report - Executive Summary: This final project report is prepared to summarize the research project titled “Assessing evapotranspiration rate changes for proposed restoration of the forested uplands of the Desert Landscape Conservation Cooperatives (LCC)” for the Desert LCC of the Bureau of Reclamation as a requirement for closing out the project. This report includes the scope of work, summary of research project, results, and conclusions.Among all of the components of the terrestrial water cycle, evapotranspiration (ET) consumes the largest amount of water. Accurate estimation of ET is very important to understand the influence of ET to the hydrologic response of recharge and runoff processes in the water...
Categories: Data, Publication; Types: Citation, Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: 2012, ATMOSPHERE, ATMOSPHERE, ATMOSPHERIC WATER VAPOR, ATMOSPHERIC WATER VAPOR, All tags...
With increasing levels of wind generation capacity on electricity systems, system operators will need to adapt their system operation policy to facilitate the efficient and cost effective integration of wind power. This paper illustrate the relative merits of adopting different system operational approaches on a system with significant wind power capacity. The impact on conventional generation, reserve levels and emissions are assessed and the implications are discussed. The illustrations show that an operational approach, which incorporates wind forecast information, while considering an increased need for reserve due to wind power, results in a more efficient integration of the wind capacity.
Categories: Publication; Types: Citation; Tags: coal, dynamics, investment, model, system
With increasing levels of wind generation capacity on electricity systems, system operators will need to adapt their system operation policy to facilitate the efficient and cost effective integration of wind power. This paper illustrate the relative merits of adopting different system operational approaches on a system with significant wind power capacity. The impact on conventional generation, reserve levels and emissions are assessed and the implications are discussed. The illustrations show that an operational approach, which incorporates wind forecast information, while considering an increased need for reserve due to wind power, results in a more efficient integration of the wind capacity.
Categories: Publication; Types: Citation; Tags: coal, dynamics, investment, model, system
With increasing levels of wind generation capacity on electricity systems, system operators will need to adapt their system operation policy to facilitate the efficient and cost effective integration of wind power. This paper illustrate the relative merits of adopting different system operational approaches on a system with significant wind power capacity. The impact on conventional generation, reserve levels and emissions are assessed and the implications are discussed. The illustrations show that an operational approach, which incorporates wind forecast information, while considering an increased need for reserve due to wind power, results in a more efficient integration of the wind capacity.
Categories: Publication; Types: Citation; Tags: coal, dynamics, investment, model, system
In the regulatory context, bioaccumulation assessment is often hampered by substantial data uncertainty as well as by the poorly understood differences often observed between results from laboratory and field bioaccumulation studies. Bioaccumulation is a complex, multifaceted process, which calls for accurate error analysis. Yet, attempts to quantify and compare propagation of error in bioaccumulation metrics across species and chemicals are rare. Here, we quantitatively assessed the combined influence of physicochemical, physiological, ecological, and environmental parameters known to affect bioaccumulation for 4 species and 2 chemicals, to assess whether uncertainty in these factors can explain the observed differences...
Summary Regional ground-water recharge estimates for Minnesota were compared to estimates made on the basis of four local- and basin-scale methods. Three local-scale methods (unsaturated-zone water balance, water-table fluctuations (WTF) using three approaches, and age dating of ground water) yielded point estimates of recharge that represent spatial scales from about 1 to about 1000 m2. A fourth method (RORA, a basin-scale analysis of streamflow records using a recession-curve-displacement technique) yielded recharge estimates at a scale of 10–1000s of km2. The RORA basin-scale recharge estimates were regionalized to estimate recharge for the entire State of Minnesota on the basis of a regional regression recharge...
Reliance on oil as an energy source for private transportation produces increasingly unfavorable social, political and environmental conditions including climate change, dependence on foreign oil, and the need for difficult choices between oil production and protection of biological systems. At the same time, the population is increasingly sedentary due largely to our reliance on the automobile for transportation. Adoption and maintenance of healthy weights and healthier lifestyles by substituting walking or biking for short trips currently taken by car could simultaneously improve health and reduce oil consumption and carbon dioxide emissions. We calculate the reduction in oil consumption and carbon dioxide emissions...
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The response of vegetation distribution, carbon, and fire to three scenarios of future climate change was simulated for California using the MC1 Dynamic General Vegetation Model. Under all three scenarios, Alpine/Subalpine Forest cover declined, and increases in the productivity of evergreen hardwoods led to the displacement of Evergreen Conifer Forest by Mixed Evergreen Forest. Grassland expanded, largely at the expense of Woodland and Shrubland, even under the cooler and less dry climate scenario where increased woody plant production was offset by increased wildfire. Increases in net primary productivity under the cooler and less dry scenario contributed to a simulated carbon sink of about 321 teragrams for California...
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Grasslands of the Sky Islands region once covered over 13 million acres in southeastern Arizona and adjacent portions of New Mexico, Sonora, and Chihuahua. Attempts to evaluate current ecological conditions suggest that approximately two thirds of these remain as intact or restorable grassland habitat. These grasslands provide watershed services such as flood control and aquifer recharge across the region, and continue to support dozens of species of concern. Prioritizing conservation interventions for these remaining grassland blocks has been challenging. Reliable data on condition and conservation value of grasslands in the region have not been systematically summarized. State and national boundaries further complicate...
Federally owned and managed public lands occupy approximately 30 percent of the land area of the United States, and anywhere from 50 percent to more than 80 percent of the land area of many of the western states. Determining the appropriate use of these lands involves balancing objectives related to economic, recreational, and conservation interests. This paper examines established and emerging conflicts within and across these objectives through both a narrative discussion of specific topics and a series of case studies. The authors find that new challenges, including pressures to devote portions of public lands to renewable energy project development and the multifaceted threats presented by climate change, will...
Recently, an active debate has emerged around greenhouse gas emissions due to indirect land use change (iLUC) of expanding agricultural areas dedicated to biofuel production. In this paper we provide a detailed analysis of the iLUC effect, and further address the issues of deforestation, irrigation water use, and crop price increases due to expanding biofuel acreage. We use GLOBIOM – an economic partial equilibrium model of the global forest, agriculture, and biomass sectors with a bottom-up representation of agricultural and forestry management practices. The results indicate that second generation biofuel production fed by wood from sustainably managed existing forests would lead to a negative iLUC factor, meaning...
The extraction of energy resources and the preservation of sensitive in-situ environmental assets are invariably mutually exclusive alternatives. The opportunity cost value of preserving the environmental assets can be assessed by recourse to resource rent taxes, and threshold values. The case study analysis carried out in this paper suggests that the preservation of these assets could be justifiable on the grounds of “acceptable sacrifice”.
A water quality model for subirrigation and subsurface drainage, ADAPT (Agricultural Drainage And Pesticide Transport), was tested with field data collected under various water table management practices near Ames, IA. Atrazine and alachlor concentrations at various soil depths for water table depths of 30, 60, and 90 cm were simulated using ADAPT model for corn growing seasons of 1989 through 1991. Daily pesticide concentrations in groundwater predicted by the model were compared with available observed data for the same site. Predicted values of atrazine and alachlor concentrations in groundwater decreased when shallow water table depths were maintained in the lysimeters. Similar trends were noticed with the observed...
With increasing levels of wind generation capacity on electricity systems, system operators will need to adapt their system operation policy to facilitate the efficient and cost effective integration of wind power. This paper illustrate the relative merits of adopting different system operational approaches on a system with significant wind power capacity. The impact on conventional generation, reserve levels and emissions are assessed and the implications are discussed. The illustrations show that an operational approach, which incorporates wind forecast information, while considering an increased need for reserve due to wind power, results in a more efficient integration of the wind capacity.
Categories: Publication; Types: Citation; Tags: coal, dynamics, investment, model, system


map background search result map search result map Sustaining the Grassland Sea Managing Changing Landscapes in the Southwestern United States Response of vegetation distribution, ecosystem productivity, and fire to climate change scenarios for California Report and Publications: Assessing Evapotranspiration Rate Changes for Proposed Restoration of the Forested Uplands of the DLCC Sustaining the Grassland Sea Report and Publications: Assessing Evapotranspiration Rate Changes for Proposed Restoration of the Forested Uplands of the DLCC Response of vegetation distribution, ecosystem productivity, and fire to climate change scenarios for California Managing Changing Landscapes in the Southwestern United States