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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
881

Evaluation of Potentially Eco-Efficient Solutions: Functional Sales and Industrial Ecology / Evaluation of Industrial Ecology, Eco-Efectiveness and Functional Sales under a framework of Eco-Efficiency

González Ocón, Santiago January 2009 (has links)
Design of products permits to yield goods and services to produce satisfaction on customers, which is measured as value. However, it is at this stage in which most of the environmental impact, from a lifecycle perspective, is added to the product. Eco-design aims at increasing value of products while reducing the burdens on the environment by means conscious design towards efficient use of resources. That efficiency, referred to as eco-efficiency, can be increased in a number of manners within environmental engineering. Traditionally, different fields have tackled materials, energy flows and products from different angles or approaches. In this thesis we describe Functional Sales (FS) and Industrial Ecology (IE) as examples of these. Within this latter, we put emphasis on Industrial Symbiosis (IS) and Eco-effectiveness. We consider these approaches are suitable to work in the framework of eco-design to increase ecoefficiency. By adding services to material products, and managing material and energy flows with a more ecological consciousness, we expect to increase value of products while reducing the impact on the environment. To analyse this potential improvement, we developed a method involving a new eco-efficiency index (VERI), that recursively intends to ease decisions on possible eco-efficient alternatives. This index and its method are applied to a case study on management of olive oil supply in region of Murcia, Spain. Here, we propose three scenarios that will involve the implementation of FS and IE to compare the outcomes in value and environmental performance against an idealised current supply chain. The results obtained, although not accurate, suggest that FS and EI should be more taken into account in eco-design and, this latter, to also consider holistic viewpoints to find more eco-efficient alternatives for a product development.
882

Miljöutredning för Bräcke Diakoni

Larsson, Anna, Bäckström, Angela January 2011 (has links)
The environmental work in Sweden has developed a lot over the past fifty years. Today, most companies have some kind of environmental work. Environmental activities are regulated by the Environmental Code, which applies in parallel with other laws. This report is an environmental review for Bräcke Diakoni. The report aims to find out how much environmental impact Bräcke Diakoni has. The report will also be used as a basis for an environmental diploma. Bräcke Diakoni is a foundation that has existed in Gothenburg since 1923 and has its operations in health, care, rehabilitation, psychiatry, children, youth, elder care and hospice. They have an environmental diploma since 2005 and are actively working to reduce their environmental impact. Data were collected through interviews, surveys, and Intranet. The environmental review includes eight of Bräcke Diakoni units are located in Bräcke, Gothenburg. The report is general, covering the environmental impact of energy, water, travel, chemicals, waste, recycling and accidents. No indentations are made. The investigation shows that business trips, electricity, district heating, service vehicles and households waste have the highest environmental impact.  Bräcke Diakoni generally has no impact on the environment that needs urgent help. At the end of the report there are suggestions for further environmental work, such as switching energy contracts, reward soft mobility among staff and reduce the missions through the purchase of video conference. Bräcke Diakoni has already taken steps to reduce their environmental impact. Among other things, they help to meet environmental quality objective "A non-toxic environment" by taking care of their hazardous waste. The fact that they use district heating contributes to the "Good Built Environment" and "Fresh air". / Miljöarbetet i Sverige har utvecklats mycket de senaste femtio åren. Idag arbetar de flesta företag med miljö på något sätt. Miljöarbetet regleras av miljöbalken som gäller parallellt med andra lagar. Den här rapporten är en miljöutredning för Bräcke Diakoni. Syftet med rapporten är att ta reda på hur stor miljöpåverkan Bräcke Diakonis verksamheter har. Rapporten ska även användas som underlag till miljödiplomering. Bräcke Diakoni är en stiftelse som funnits i Göteborg sedan år 1923 och har verksamheter inom hälsa, vård, rehab, psykiatri, barn, ungdom, äldreomsorg och hospice. De är miljödiplomerade sedan 2005 och arbetar aktivt för att minska sin miljöpåverkan. Data har samlats in genom intervjuer, inventeringar och Intranätet. Miljöutredningen omfattar åtta av Bräcke Diakonis enheter som är lokaliserade i Bräcke, Göteborg. Utredningen är övergripande och omfattar miljöpåverkan från energiförbrukning, vatten, resor, kemikalier, avfall, återvinning och olyckor. Inga fördjupningar har gjorts. Högst miljöpåverkan fick tjänsteresor, el, fjärrvärme, tjänstefordon och hushållssopor. Bräcke Diakoni har överlag ingen miljöpåverkan som behöver akuta åtgärder. I slutet av rapporten finns förbättringsförslag för fortsatt miljöarbete, exempelvis byta energiavtal, belöna miljövänligt resande bland personalen och minska på tjänsteresor genom införskaffande av videokonferensanläggning. Bräcke Diakoni har redan vidtagit åtgärder för att minska sin miljöpåverkan. Bland annat bidrar de till att uppfylla miljökvalitetsmålet ”Giftfri miljö” genom att ta hand om sitt farliga avfall. Att de använder fjärrvärme bidrar till att uppfylla ”God bebyggd miljö” samt ” Frisk luft”.
883

Indirekt miljöpåverkan inom tjänstesektorn : En intervjustudie om hanteringen av indirekt miljöpåverkan inom några organisationers miljöledningssystem / Indirect Environmental Impact within the Service Industry : An Interview Study about the Management of Indirect Environmental Impact within a Few Organisations Environmental Management System

Sharifian, Ladan January 2008 (has links)
I och med samhällets utveckling från ett jordbrukssamhälle till ett industriellt samhälle, och vidare till ett tjänste- och kunskapssamhälle har antalet tjänsteföretag växt, och därmed även miljöpåverkan från denna sektor. Tjänstesektorns miljöpåverkan kan delas upp i två delar, en direkt miljöpåverkan kopplat till kontorsverksamheten, såsom energianvändning, samt en indirekt miljöpåverkan, som är ett resultat av tjänstens framtida nytta och bestående värde. Ett vanligt verktyg som svenska företag, och andra typer av organisationer, använder sig av för att strukturera upp sitt miljöarbete är miljöledningssystem enligt den internationella standarden ISO 14001. Miljöledningssystem är dock inte lika vanligt förekommande i tjänstesektorn som inom tillverkningsindustrin. Syftet med denna uppsats är därför att studera hur indirekt miljöpåverkan hanteras, och kan bli mer hanterbart, inom tjänstesektorn. Detta belyses genom att diskutera varför organisationer har valt att certifiera sina verksamheter, hur organisationer definierar, och hanterar, indirekt miljöpåverkan, samt vilken roll ledningen och medarbetarna har vid hanteringen av den indirekta miljöpåverkan. Studien utfördes genom semistrukturerade intervjuer med miljöansvariga på fyra tjänsteföretag samt fyra myndigheter. Resultatet av intervjuerna sammanställdes, analyserades och kopplades samman med tidigare studier. Därefter drogs ett antal slutsatser. Slutsatserna visar att organisationerna har valt att certifiera sina verksamheter p.g.a. efterfrågan och intresse hos kunder, samt för att visa på att företaget besitter en hög miljökompetens. De flesta av de medverkande organisationerna har format egna definitioner av begreppet indirekt miljöpåverkan. Gemensamt för dessa definitioner är att samtliga kopplas ihop med kundernas miljöpåverkan. Slutsatserna visar även att hanteringen av organisationernas indirekta miljöpåverkan sker inom ramen för deras miljöledningssystem. Det upplevs dock mycket svårt att formulera mätbara miljömål som berör den indirekta miljöpåverkan vilket troligen beror på att ISO 14001 bl.a. ställer krav på att det ska finnas mätbara mål och att möjligheterna till att formulera ickekvantifierbara miljömål har undgått organisationerna. Ett alternativ för att underlätta hanteringen av den indirekta miljöpåverkan skulle kunna vara att låta bli att dela in miljöpåverkan i kategorierna direkt och indirekt, och istället se till den totala miljöpåverkan med hjälp av ett processbaserat tillvägagångssätt. Det kan även diskuteras huruvida begreppet ”mätningar” är lämpligt vid arbetet med miljömål då termen leder till tankar kring kvantifierbarhet. Vidare visar slutsatserna att ledningens och medarbetarnas kompetens samt engagemang är två nyckelfaktorer för att organisationerna ska lyckas med miljöarbetet.
884

Lifecycle Assessment for Strategic Product Design and Management

Muir, Michael Christopher 28 August 2006 (has links)
With the advent of digital imaging technology, the options available to consumers in consumer imaging have increased tremendously. From image capture through image processing and output, many options have emerged; however, the relative environmental impacts of these different options are not clear cut. Simplistically, one might say that the use of a digital camera has a lesser environmental burden than the use of a reloadable film camera because the image produced as a result of using the digital camera avoids chemicals in film developing. However, digital cameras require electronics and computers that need energy; and, energy production is one of the contributors to greenhouse gasses like CO2. Assessment of the environmental impacts of these different options can help provide feedback to decision makers and insights that will help reduce environmental impact through product system design. One tool that has been used to relate environmental impacts with functions provide to consumers through products or services is Life Cycle Assessment (LCA). LCA, which has been standardized by the International Standards Organization (ISO) in ISO14000, is used here to evaluate both traditional film and digital imaging systems. Data from publicly available databases and both external and internal Eastman Kodak Company studies were utilized to develop LCA modules for the different processes involved. Product and service business models are explored for both technologies through ten different imaging and output scenarios. The functional unit used is the capture, processing and output of one 4 x6 image. Four impact categories (energy use, greenhouse emission, water use and waste generation) across four life cycle phases (upstream, distribution, use, and end of life) are explored for the ten scenarios. LCA is also evaluated as a tool to help facilitate strategic level environmental performance issues with both new and established business activities. Sensitivity analysis is also performed to evaluate the impact of assumptions made in the course of the assessment and comments are made regarding the effectiveness of LCA for strategic assessment and product service strategies in lowering environmental impact. Results indicate that the lowest impact scenarios are Digital Capture to LCD Display for Greenhouse Emissions and Energy Use and Film Capture to Wholesale Print for Water Use and Waste Generation. Highest impacts were seen for Greenhouse Emissions in the Film Capture to Retail Print scenario. In the Energy Use and Water Use category, the Digital Capture to CRT Computer Display was the highest scenario. For Waste Generation, the Digital Capture to Inkjet Print was the highest impact scenario.
885

The Mechanism of Long-Term Environmental Impact Assessment for Large Oil Spill Events

Tsao, Kai 19 October 2011 (has links)
Ever since humans began using cargo by sea to transport oil, oil spill incidents have occurred on different scales in different environments. Oil leaks by cargo tankers on the high seas have a bigger and more serious impact on the environment. Among the many oil spills in the ocean, the most serious was the Exxon Valdez incident in Alaska¡¦s Prince William Sound (PWS). While it may not have been the largest spill in terms of the volume of oil leaked, its effects were far-reaching; the location of the spill was in the sensitive area between the temperate and subtropical zones, and it was home to many fish, migratory birds, and mammals. Therefore, this location has become an important place for researchers to study the environmental and biological impacts of an oil leak. In the past, there have been several studies conducted from various perspectives and in various stages. In 2001, the Greek oil tanker The Amorgos ran aground near Kenting National Park¡¦s Long-Keng Environmental Protection Zone and seriously damaged the ecological environment. Taiwanese studies on the ecological impacts of oil spills include investigations and evaluations done on a short-term basis, and have been mainly focused on contingency plans and designs, evaluation systems, and handling technology. Thus, the purpose of this paper is to use related studies conducted in Alaska PWS to evaluate the ecological system in the Long-Keng area and to assess the long-term impacts of an oil spill in the ecological sensitive area of Taiwan.
886

The Study of Citizen Participation and the Hi-Tech Petrochemical Zone Transformed from China Petroleum Corporation

Tsai, Chin-I 28 August 2006 (has links)
In recent years, ¡§Boost the economy and cut down the unemployment rate¡¨ has become a common understanding of the people in Taiwan, which is the government¡¦s goal for economic development as well. One of the most effective strategies to boost the economy is to encourage investment. However, the rising concern of environmental protection and the consciousness of living peacefully with the mother natural have become a trend nowadays. Furthermore, not only business but also the government and the neighboring residents have increased their standards for environmental protection. Therefore, the industry has tended to be more prudent to any new development project. What deserves to be mentioned is, no matter how wonderful a proposed project is, without the support of local residents, no project can be executed. Therefore, we should regard the citizen participation and environmental impact assessment (EIA). China Petroleum Corporation (CPC) proposed at the end of 2002, aiming to make the transformation from an oil plant to a hi-tech petrochemical zone on Kaohsiung Oil Refinery, with new petrochemical equipment and nono-technology. Ministry of Economic Affairs has agreed with the proposed transformation with the condition that CPC has to obtain approval from the local residents, representatives and government. According to the analysis of power interaction, this study intends to provide related policy suggestions to the government and CPC with the purpose of economic prosperity. For the evolution of modern society, sustainable development and business continuity will play important roles. Besides adopting opinion poll, Delphi Technique is also applied as the research methodology to carry on experts¡¦ interviews and questionnaires investigation.
887

A strategic planning approach for the operational-environmental problem of air transportation system terminal areas

Jimenez, Hernando 16 November 2009 (has links)
The air transportation system plays a crucial role in modern society, comprising a major industrial sector as well as a key driver for adjacent economies. Moreover, it is a prime enabler of the modern way of life, characterized by access to products and services from around the world, and access to remote locations. Therefore there is a strong incentive to maintain the system and promote its growth. None the less, important challenges have plagued civil aviation, particularly the commercial aviation sector. On one hand, demand for air travel has grown dramatically and at an accelerated pace, in part due to the deregulation of airlines in 1978, providing airlines with the freedom to arrange their operational schedule freely and compete for markets. The dynamic nature of demand and its fast-paced growth contrasts with the relative rigidity of air transportation infrastructure development and the sluggish evolution of its operational architecture. The supply-demand mismatch that results has led to degradation in system efficiency, excessive delays, and substantial economic losses. This phenomenon is particularly exacerbated in the terminal area of major airports which have inevitably become operational choke points. On the other hand the environmental impact of air transportation, embodied primarily by the emissions and noise caused by aircraft operations, has also grown as a result of the increase in aviation activity, and has therefore become a major issue of public interest. Airport communities experience said environmental impact most intensely, particularly those associated with bottleneck airports, and thus represent a uniquely strong force opposing further expansion of air transportation in these areas where it is most needed. Past efforts to address these challenges have been notably stovepiped and have failed to recognize the importance of the relationship between the operational nature of the system and its environmental impact. Only recently have research efforts begun to incorporate a joint view of the operational-environmental problem that attempts to formulate solutions accordingly. However, the state of the art has yet to answer some of the most fundamental questions. First, the relationship between operational and environmental elements has not been quantified conclusively. Doing so is vital to understand the operational-environmental nature of terminal areas before any solutions can be considered. Secondly, many different types of solution alternatives have been proposed, such as the construction of new runways, redesign of operational procedures, introduction of advanced aircraft concepts, and transformation of airspace capabilities. However, a direct comparison between dissimilar alternatives that accounts for operational and environmental issues is rarely found, and yet remains crucial in the formulation of a solution portfolio. More importantly, the additive and countervailing interactions that different solutions have on each other are widely recognized but remain, for the most part, unknown. Because all solutions under consideration require an extended period of time to develop and represent very large economic commitments, the selection of a portfolio demands a careful look at the future to determine the adequate measures that should be pursued in the present. In response to this methodological need, this thesis proposes a strategic planning approach to investigate the operational-environmental nature of the air transportation system, as well as the adequacy of solution alternatives for terminal areas in the formulation of a portfolio. The state of the art currently incorporates elements of strategic planning, but has yet to address two important methodological gaps. First, the inherent systemic complexity of airport performance obfuscates its quantitative characterization, which is paramount in attaining adequate insight and understanding to support informed strategic decision-making in the selection of terminal area solutions. Second, there is significant uncertainty about the evolution of the aviation demand and its operational context, making the use of forecasts grossly inadequate for this application. A scenario-based approach is used in its place, but the current frameworks for the generation, evaluation, and selection of an adequate scenario set currently lack traceability and methodological rigor. To address the first gap, this thesis proposes the use of well established statistical analysis techniques, leveraging on recent developments in interactive data visualization capabilities, to quantitatively characterize the interactions, sensitivities, and tradeoffs prevalent in the complex behavior of airport operational and environmental performance. Within the strategic airport planning process, this approach is used in the assessment of airport performance under current/reference conditions, as well as in the evaluation of terminal area solutions under projected demand conditions. More specifically, customized designs of experiments are utilized to guide the intelligent selection and definition of modeling and simulation runs that will yield greater understanding, insight, and information about the inherent systemic complexity of a terminal area, with minimal computational expense. Regression analysis leverages the creation of response surface equations that explicitly and quantitatively capture the behavior of system metrics of interest as functions of factors or terminal area solutions. This explicit mathematical characterization enables a variety of interactive visualization schemes that allow analysts and decision makers to confirm or rectify expected patterns of behavior, and to discover the unknown and the unexpected. Said visualization schemes are also instrumental in communicating, in a very direct and succinct fashion, complex relationships, sensitivities, tradeoffs, and interactions, that would be otherwise too complex to explain or communicate transparently. More importantly, this approach provides a rigorous and formalized mathematical framework within which the statistical significance of different factors or terminal area solutions can be quantitatively and explicitly assessed, primarily by means of statistical hypotheses testing of regression parameter estimates, such as the analysis of variance, or the t-statistic test. This proposed approach does not suggest a new strategic planning process, but rather improves specific steps pertaining to performance assessments, and builds upon established practices and the recommended planning process for airports to leverage on the decades of experience supporting the existing strategic airport planning paradigm. On the other hand, the proposed approach recognizes the methodological limitations and constraints that lead to the lack of terminal area performance characterization within the strategic planning process, embodied primarily by computational constraints and unmanageable systemic complexity, and directly addresses these shortcomings by incorporating mature statistical analysis techniques into key steps of said process. In turn, the proposed approach represents a novel adaptation of the strategic airport planning process that results in greater knowledge, insight, and understanding, at a resource cost comparable to current airport planning practices. As such, this proposed approach is demonstrated using the Atlanta Hartsfield-Jackson International Airport as a representative test case, and constitutes a contribution to strategic airport planning given that it supports strategic decision making by revealing, at an acceptable analysis and computational expense, the various sensitivities, interactions, and tradeoffs of interest in operational-environmental performance that would otherwise remain implicit and obfuscated by systemic complexity. For the research documented in this thesis, a modeling and simulation environment was created featuring three primary components. First, a generator of schedules of operations, based primarily on previous work on aviation demand characterization, whereby growth factors and scheduling adjustment algorithms are applied on appropriate baseline schedules so as to generate notional operational sets representative of consistent future demand conditions. The second component pertains to the modeling and simulation of aircraft operations, defined by a schedule of operations, on the airport surface and within its terminal airspace. This component is a discrete event simulator for multiple queuing models that captures the operational architecture of the entire terminal area along with all the necessary operational logic pertaining to simulated ATC functions, rules, and standard practices. The third and final component is comprised of legacy aircraft performance, emissions and dispersion, and noise exposure modeling tools, that use the simulation history of aircraft movements to generate estimates of fuel burn, emissions, and noise. A set of designed modeling and simulation experiments were conducted to examine the interactions between exogenous and endogenous factors, as well as their main and quadratic effect, on operational metrics such as delay, and on fuel burn as the primary environmental metrics. Results show that for a gate-hold scheme used to manage surface traffic density, the departure queue threshold features a statistically significant interaction with the increasing number of operations, but that otherwise the relative percent change in the number of operations remains as the predominant exogenous factor driving operational and environmental performance. A separate design of modeling and simulation experiments was conducted to test the statistical significance of proposed geographical regional categories that could potentially be used to classify operations and capture operational demand characteristics such as fleet mix, time of day distribution, and arrival/departure route distribution. Results show that whereas the proposed categorization is statistically significant for a few metric of interest, marginally significant for others, and not statistically significant for most metrics, the proposed regional classification scheme is not appropriate for operational demand characterization. The implementation of the proposed approach for the assessment of terminal area solutions incorporates the use of discrete response surface equations, and eliminates the use of quadratic terms that have no practical significance in this context. Rather, attention is entire placed on the main effects of different terminal area solutions, namely additional airport infrastructure, operational improvements, and advanced aircraft concepts, modeled as discrete independent variables for the regression model. Results reveal that an additional runway and a new international terminal, as well as reduced aircraft separation, have a major effect on all operational metrics of interest. In particular, the additional runway has a dominant effect for departure delay metrics and gate hold periods, with moderate interactions with respect to separation reduction. On the other hand, operational metrics for arrivals are co-dependent on additional infrastructure and separation reduction, featuring marginal improvements whenever these two solutions are implemented in isolation, but featuring a dramatic compounding effect when implemented in combination. The magnitude of these main effects for departures and of the interaction between these solutions for arrivals is confirmed through appropriate statistical significance testing. Finally, the inclusion o advanced aircraft concepts is shown to be most beneficial for airborne arrival operations and to a lesser extent for arrival ground movements. More specifically, advanced aircraft concepts were found to be primarily responsible for reductions in volatile organic compounds, unburned hydrocarbons, and particulate matter in this flight regime, but featured relevant interactions with separation reduction and additional airport infrastructure. To address the second gap, pertaining to the selection of scenarios for strategic airport planning, a technique for risk-based scenario construction, evaluation, and selection is proposed, incorporating n-dimensional dependence tree probability approximations into a morphological analysis approach. This approach to scenario construction and downselection is a distinct and novel contribution to the scenario planning field as it provides a mathematically and explicitly testable definition for an H parameter, contrasting with the qualitative alternatives in the current state of the art, which can be used in morphological analysis for scenario construction and downselection. By demonstrating that dependence tree probability product approximations are an adequate aggregation function, probability can be used for scenario construction and downselection without any mathematical or methodological restriction on the resolution of the probability scale or the number of morphological alternatives that have previously plagued probabilization and scenario downselection approaches. In addition, this approach requires expert input elicitation that is comparable or less than the current state of the art practices.
888

Environmental implications of leasing

Intlekofer, Koji 03 December 2009 (has links)
This thesis will investigate the possibility of leasing as a 'greener' form of business transaction. With leasing, the customer pays for the service obtained form the product, but does not own the physical asset; ownership remains with the lessor. This has been claimed to increase resource productivity and close material loops. Numerous complications exist, however, such as tax regulations limiting operating leases to terms of 75% of the total product's life. In addition, no clear pattern has emerged in leasing practices, and in most cases manufacturers approach leasing on an ad hoc basis. Research has found that usage-phase impacts play a major role in determining the advantages realized by leasing. Products such as vehicles or refrigerators that continually consume energy negatively impact the environment much more during their use than during manufacturing or transportation. Because most lease agreements contain maintenance contracts, the opportunity to upgrade and increase product efficiency during this use-phase is paramount to reducing negative impacts. Remanufacturing also shows potential to further reduce resource requirements. However, if product efficiency is not improving significantly, remanufacturing alone does not make a significant impact. In some cases, such as carpets, remanufacturing is not practical, but recycling can be utilized. However, tax regulations require leased terms to be less than that of a product's designed life, hastening replacement. This has the potential to offset any advantages seen with a lease agreement. Academic work in this area remains very limited and product-specific. Case study analyses performed in this thesis found that increased product turnover can actually be environmentally beneficial when product technology is improving. These gains can be further improved with remanufacturing and optimized product replacement moderated by lease agreements. If usage energy is significantly less than manufacturing energy, leasing has little value for reducing impacts. Also leasing may motivate closed material loops, without improving product efficiencies there is no advantage to optimizing life cycles with lease contracts.
889

Aquatic plant-herbivore interactions across multiple spatial scales.

Morrison, Wendy Elizabeth 21 May 2010 (has links)
For decades scientists believed that herbivory had minimal impact on freshwater ecosystems. We now know that herbivory in freshwater systems equals or exceeds herbivory in terrestrial and marine systems. In extreme cases, herbivores can change clear, macrophyte dominated ecosystems into turbid plankton dominated ecosystems. Even though research on plant-herbivore interactions in freshwater systems has increased, there is still much that is unknown. This thesis is comprised of four studies investigating freshwater plant-herbivore interactions across multiple spatial scales. The first study investigated how induced chemical defenses in Cabomba caroliniana suppress herbivore consumption and growth as well as how this herbivore-generated change in plant chemistry affects the growth of plant associated microbes. At the spatial scale of individual ponds or lakes, consumers that induce their host plants may also be indirectly affecting other consumers and microbial pathogens via changes in this shared resource. The second study moves to an ecosystem scale and investigates how exotic versus native apple snails may impact Everglades' habitats. We investigated plant preference, consumption, growth and conversion efficiencies in the singly native apple snail to occur in the U.S. (Pomacea paludosa) versus four introduced species (P. canaliculata, P. insularum, P. haustrum and P. diffusa). We found that even though plant preferences are similar, invasive snails tend to eat more, grow more rapidly, and sometimes more efficiently than natives. This suggests that invasive species could have a large impact on the environment, especially the abundance of submerged plants. The third study investigated how palatability of freshwater plants varies with latitude (i.e. geographic scale). Increased herbivory at lower latitudes is hypothesized to select for increased plant defenses, which has been shown to be true for tropical forests, salt marshes, and seaweeds. When we contrasted eight confamilial plants collected in Indiana versus Southern Florida, three of four herbivores significantly preferred northern plants. When we evaluated a second set of plants collected from Indiana versus Central Florida, only one of three herbivores preferred the northern plants. Overall, our results suggest a preference for northern plants, but the strength of this relationship was variable. We hypothesize that this variability may be driven by 1) local variance in herbivore pressure that creates variance in plant defenses, and/or 2) the effect of winter length on the survival and feeding rate of herbivores. The final study expanded to a world scale, and investigated herbivore preference for native vs exotic plants. We found that both N. American crayfish and S. American snails preferred exotic plants over confamilial natives, despite responding to different plant characteristics. The single species of apple snail that occurs in N. American showed no preference for native or exotic plants from a N. American perspective, but instead exhibited preferences that correlated with its history of evolution in S. America. As the N. American species is a sister species of the S. American snails, feeding by the N. American snail appears more affected by its S. American lineage than its recent history in N. America. This suggests that phylogenetic legacy will affect choices of the herbivore as well as resistance or susceptibility of plants.
890

Indirekt miljöpåverkan inom tjänstesektorn : En intervjustudie om hanteringen av indirekt miljöpåverkan inom några organisationers miljöledningssystem / Indirect Environmental Impact within the Service Industry : An Interview Study about the Management of Indirect Environmental Impact within a Few Organisations Environmental Management System

Sharifian, Ladan January 2008 (has links)
<p><p>I och med samhällets utveckling från ett jordbrukssamhälle till ett industriellt samhälle, och vidare till ett tjänste- och kunskapssamhälle har antalet tjänsteföretag växt, och därmed även miljöpåverkan från denna sektor. Tjänstesektorns miljöpåverkan kan delas upp i två delar, en direkt miljöpåverkan kopplat till kontorsverksamheten, såsom energianvändning, samt en indirekt miljöpåverkan, som är ett resultat av tjänstens framtida nytta och bestående värde. Ett vanligt verktyg som svenska företag, och andra typer av organisationer, använder sig av för att strukturera upp sitt miljöarbete är miljöledningssystem enligt den internationella standarden ISO 14001. Miljöledningssystem är dock inte lika vanligt förekommande i tjänstesektorn som inom tillverkningsindustrin. Syftet med denna uppsats är därför att studera hur indirekt miljöpåverkan hanteras, och kan bli mer hanterbart, inom tjänstesektorn. Detta belyses genom att diskutera varför organisationer har valt att certifiera sina verksamheter, hur organisationer definierar, och hanterar, indirekt miljöpåverkan, samt vilken roll ledningen och medarbetarna har vid hanteringen av den indirekta miljöpåverkan.</p><p>Studien utfördes genom semistrukturerade intervjuer med miljöansvariga på fyra tjänsteföretag samt fyra myndigheter. Resultatet av intervjuerna sammanställdes, analyserades och kopplades samman med tidigare studier. Därefter drogs ett antal slutsatser. Slutsatserna visar att organisationerna har valt att certifiera sina verksamheter p.g.a. efterfrågan och intresse hos kunder, samt för att visa på att företaget besitter en hög miljökompetens. De flesta av de medverkande organisationerna har format egna definitioner av begreppet indirekt miljöpåverkan. Gemensamt för dessa definitioner är att samtliga kopplas ihop med kundernas miljöpåverkan. Slutsatserna visar även att hanteringen av organisationernas indirekta miljöpåverkan sker inom ramen för deras miljöledningssystem. Det upplevs dock mycket svårt att formulera mätbara miljömål som berör den indirekta miljöpåverkan vilket troligen beror på att ISO 14001 bl.a. ställer krav på att det ska finnas mätbara mål och att möjligheterna till att formulera ickekvantifierbara miljömål har undgått organisationerna. Ett alternativ för att underlätta hanteringen av den indirekta miljöpåverkan skulle kunna vara att låta bli att dela in miljöpåverkan i kategorierna direkt och indirekt, och istället se till den totala miljöpåverkan med hjälp av ett processbaserat tillvägagångssätt. Det kan även diskuteras huruvida begreppet ”mätningar” är lämpligt vid arbetet med miljömål då termen leder till tankar kring kvantifierbarhet. Vidare visar slutsatserna att ledningens och medarbetarnas kompetens samt engagemang är två nyckelfaktorer för att organisationerna ska lyckas med miljöarbetet.</p></p>

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