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Interspecific interactions of herbivores sharing a host plant may be important in structuring herbivore communities. We investigated host plant-mediated interactions of root (Hylobius transversovittatus) and leaf herbivores (Galerucella calmariensis), released to control purple loosestrife (Lythrum salicaria) in North America, in field and potted plant experiments. In the potted plant experiments, leaf herbivory by G. calmariensis reduced H. transversovittatus larval survival (but not larval development) but did not affect oviposition preference. Root herbivory by H. transversovittatus did not affect either G. calmariensis fitness or oviposition preference. In field cage experiments, we found no evidence of interspecific...
This study deals with modeling and analyzing the performance of greenhouses from the power plant through the heating system to the greenhouse envelope using exergy analysis method, the so-called low exergy or LowEx approach, which has been and still being successfully used in sustainable buildings design, for the first time to the best of the author’s knowledge. For the heating applications, three options are studied with (i) a solar assisted vertical ground-source heat pump greenhouse heating system, (ii) a wood biomass boiler, and (iii) a natural gas boiler, which are driven by renewable and non-renewable energy sources. In this regard, two various greenhouses, the so-called small greenhouse and large greenhouse,...
This paper investigates the potential for systematic errors in the Energy Information Administration’s (EIA) widely used Annual Energy Outlook, focusing on the near- to midterm projections of energy demand. Based on analysis of the EIA’s 22-year projection record, we find a fairly modest but persistent tendency to underestimate total energy demand by an average of 2 percent per year after controlling for projection errors in gross domestic product, oil prices, and heating/cooling degree days. For 14 individual fuels/consuming sectors routinely reported by the EIA, we observe a great deal of directional consistency in the errors over time, ranging up to 7 percent per year. Electric utility renewables, electric utility...
Ecological evaluation is essential for remediation, restoration, and Natural Resource Damage Assessment (NRDA), and forms the basis for many management practices. These include determining status and trends of biological, physical, or chemical/radiological conditions, conducting environmental impact assessments, performing remedial actions should remediation fail, managing ecosystems and wildlife, and assessing the efficacy of remediation, restoration, and long-term stewardship. The objective of this paper is to explore the meanings of these assessments, examine the relationships among them, and suggest methods of integration that will move environmental management forward. While remediation, restoration, and NRDA,...
Chemical treatment methods have been used with varying degrees of success for mitigating the environmental effects resulting from oil spills. These methods include dispersing, herding, and gelling a floating oil slick; sinking the oil; burning the oil mass either on open waters or on the affected shoreline; and applying film-forming chemical agents to protect shorelines from oil that eludes offshore cleanup. The latest technical information on the applicability and effectiveness of these approaches for treating and controlling oil spills is presented
Plastics have now become indispensable materials in the modern world and application in the industrial field is continually increasing. The properties of the oil derived from waste plastics were analyzed and found that it has properties similar to that of diesel. Waste plastic oil (WPO) was tested as a fuel in a D.I. diesel engine and its performance characteristics were analysed and compared with diesel fuel (DF) operation. It is observed that the engine could operate with 100% waste plastic oil and can be used as fuel in diesel engines. Oxides of nitrogen (NOx) was higher by about 25% and carbon monoxide (CO) increased by 5% for waste plastic oil operation compared to diesel fuel (DF) operation. Hydrocarbon was...
The subject of ecological indicators is both complex and technical. Indicators are low signal/noise read-outs from systems reflecting deeply embedded processes. Informal, single factor indicators reflect superficial properties. Complex systems require formal, multifactorial measures. Conceptual basis, importance and bandwidth of variables, reliability and statistical properties, data and skill requirements, data quality and archiving, robustness under technology change, and cost/benefit issues are factors in indicator design. Network models enable formalism to be brought to the indicator problem. Networks are oriented in time-forward and reverse directions, giving rise to environs. Output environs span network flows...
The effects of 120 days of high-intensity (80-kV/m) 60-Hz electric field exposure on hematologic constituents were investigated using a three-generation design including 135 field-exposed and 135 sham-exposed male Sprague-Dawley rats. Statistical tests performed included the multivariate analysis of variance, the univariate analysis of variance, and tests of simple effects. Total white cell count, lymphocyte count, and eosinophil count were significantly lower in field-exposed subjects; however, none of the red cell parameters differed significantly. The observed hematologic variations related to the exposure of a high-intensity electric field are consistent with those observed in animals responding to a mild stressor.
The uptake of nitrous oxide (N2O) occurs at the surface of the earth both in terrestrial and aquatic systems. This uptake is usually neglected in N2O budget studies. In this article, we discuss the likeliness of N2O uptake in different systems. These systems include soils as well as groundwater systems, riparian zones and surface waters. We address the possible consequences of ignoring surface sinks for N2O in global budgets as well as in national emission inventories. Our estimated surface sink is relatively small compared to the estimates of the present-day global emissions. Neglecting a possible surface sink of N2O may, therefore, not have major consequences for atmospheric budget studies on the global scale....
Chemical treatment methods have been used with varying degrees of success for mitigating the environmental effects resulting from oil spills. These methods include dispersing, herding, and gelling a floating oil slick; sinking the oil; burning the oil mass either on open waters or on the affected shoreline; and applying film-forming chemical agents to protect shorelines from oil that eludes offshore cleanup. The latest technical information on the applicability and effectiveness of these approaches for treating and controlling oil spills is presented
Ecological evaluation is essential for remediation, restoration, and Natural Resource Damage Assessment (NRDA), and forms the basis for many management practices. These include determining status and trends of biological, physical, or chemical/radiological conditions, conducting environmental impact assessments, performing remedial actions should remediation fail, managing ecosystems and wildlife, and assessing the efficacy of remediation, restoration, and long-term stewardship. The objective of this paper is to explore the meanings of these assessments, examine the relationships among them, and suggest methods of integration that will move environmental management forward. While remediation, restoration, and NRDA,...
Plastics have now become indispensable materials in the modern world and application in the industrial field is continually increasing. The properties of the oil derived from waste plastics were analyzed and found that it has properties similar to that of diesel. Waste plastic oil (WPO) was tested as a fuel in a D.I. diesel engine and its performance characteristics were analysed and compared with diesel fuel (DF) operation. It is observed that the engine could operate with 100% waste plastic oil and can be used as fuel in diesel engines. Oxides of nitrogen (NOx) was higher by about 25% and carbon monoxide (CO) increased by 5% for waste plastic oil operation compared to diesel fuel (DF) operation. Hydrocarbon was...
Chemical treatment methods have been used with varying degrees of success for mitigating the environmental effects resulting from oil spills. These methods include dispersing, herding, and gelling a floating oil slick; sinking the oil; burning the oil mass either on open waters or on the affected shoreline; and applying film-forming chemical agents to protect shorelines from oil that eludes offshore cleanup. The latest technical information on the applicability and effectiveness of these approaches for treating and controlling oil spills is presented
The uptake of nitrous oxide (N2O) occurs at the surface of the earth both in terrestrial and aquatic systems. This uptake is usually neglected in N2O budget studies. In this article, we discuss the likeliness of N2O uptake in different systems. These systems include soils as well as groundwater systems, riparian zones and surface waters. We address the possible consequences of ignoring surface sinks for N2O in global budgets as well as in national emission inventories. Our estimated surface sink is relatively small compared to the estimates of the present-day global emissions. Neglecting a possible surface sink of N2O may, therefore, not have major consequences for atmospheric budget studies on the global scale....
We have conducted a detailed analysis of costs associated with today’s technology for CO2 separation and capture at three types of power plants: integrated coal gasification combined cycles (IGCC), pulverized coal-fired simple cycles (PC), and natural gas-fired combined cycles (NGCC). The analysis was based on studies from the literature that analyzed the economics of capturing CO2 emitted at power plants. In this paper, we present a composite cost model and perform a sensitivity analysis to identify the cost-drivers for capture. We conclude that with new developments, CO2 capture and sequestration can become a cost-effective mitigation pathway.
The potential variance in feedstock costs can have significant implications for the cost of a biofuel and the financial viability of a biofuel facility. This paper employs the Grange Feed Costing Model to assess the cost of on-farm biomethane production using grass silages produced under a range of management scenarios. These costs were compared with the cost of wheat grain and sugarbeet roots for ethanol production at an industrial scale. Of the three feedstocks examined, grass silage represents the cheapest feedstock per GJ of biofuel produced. At a production cost of €27/tonne (t) feedstock (or €150/t volatile solids (VS)), the feedstock production cost of grass silage per gigajoule (GJ) of biofuel (€12.27) is...
The effects of 120 days of high-intensity (80-kV/m) 60-Hz electric field exposure on hematologic constituents were investigated using a three-generation design including 135 field-exposed and 135 sham-exposed male Sprague-Dawley rats. Statistical tests performed included the multivariate analysis of variance, the univariate analysis of variance, and tests of simple effects. Total white cell count, lymphocyte count, and eosinophil count were significantly lower in field-exposed subjects; however, none of the red cell parameters differed significantly. The observed hematologic variations related to the exposure of a high-intensity electric field are consistent with those observed in animals responding to a mild stressor.
Hydrates in nature have been known for a long time. In the last couple of decades the possibility of commercial utilization of natural hydrates has arisen as an alternative energy source. This paper asks 21 questions that, in the author’s opinion, need to be addressed and answered correctly before one can be confident one understands the scope of the problem one is facing in attempting to address the role of natural hydrates, both commercially and geologically.
Coalbed methane is one of the most important and valuable natural resources in the Western United States. The natural gas that results from CBM development is the cleanest burning fossil fuel, and the extensive domestic supply makes it a central element of the national goal of a secure supply of energy. Demand for natural gas will continue to grow and CBM will play an increasingly larger role in meeting that demand. CBM production has expanded tremendously over the past decade, and the rapidity with which development has expanded has resulted in stresses and tension in affected communities. Development of this important energy resource must be balanced with a number of other important goals of protecting water,...
The uptake of nitrous oxide (N2O) occurs at the surface of the earth both in terrestrial and aquatic systems. This uptake is usually neglected in N2O budget studies. In this article, we discuss the likeliness of N2O uptake in different systems. These systems include soils as well as groundwater systems, riparian zones and surface waters. We address the possible consequences of ignoring surface sinks for N2O in global budgets as well as in national emission inventories. Our estimated surface sink is relatively small compared to the estimates of the present-day global emissions. Neglecting a possible surface sink of N2O may, therefore, not have major consequences for atmospheric budget studies on the global scale....