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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.
1

AMS Lighter Footprint Strategy

Doherty, Eric 31 January 2008 (has links)
In January 2007 the AMS approved an Environmental Sustainability Policy designed to make the AMS’s well-established environmental actions more effective and consistent. The Policy vision includes the responsibility the AMS has with respect to the current ecological crisis and strongly states our commitment to meeting this obligation: The AMS recognizes the ecological crisis humanity faces and the special responsibility universities, and university students, have in finding and implementing solutions. We acknowledge our obligations as global citizens and strive to create a sustainable and equitable future for all. The AMS will be a leader in reducing the university campus’ ecological footprint to sustainable levels and in fostering environmental justice in our own operations and through our relationships with the University community and the broader community. The AMS will be an engine for new ideas and innovation, and will be a model for the University and for other student organizations to follow. The purposes of the Strategy defined in the AMS Environmental Sustainability Policy include: • To guide the AMS’s work to areas where we can have the greatest effect. • To establish procedures for monitoring and reporting on progress. • To showcase the AMS’s leadership in order to distinguish the AMS and our businesses from the University as a whole.
2

Topographically-based landscape-scale ecological mapping in Pennsylvania

Kong, Ningning. January 2006 (has links)
Thesis (Ph.D.)--Pennsylvania State University, 2006. / Mode of access: World Wide Web.
3

Topographically-based landscape-scale ecological mapping in Pennsylvania

Kong, Ningning. January 2006 (has links)
Thesis (Ph.D.)--Pennsylvania State University, 2006. / Mode of access: World Wide Web.
4

Modelling the range-wide density patterns of the Arthroleptella lightfooti using acoustic monitoring data

Poongavanan, Jenicca 16 March 2020 (has links)
Species distributions are often limited by environmental factors and according to the abundant—centre hypothesis, abundance should be highest Where the environment is most favourable for the species. So, do the same environmental factors determine occurrence and abundance patterns inside the range? I examined this question using Arthroleptella lightfooti, a species of frog from the family of Pyxicephalidae, endemic to the mountains of the Cape peninsula. South Africa. I used density estimates obtained from acoustic Spatially Explicit Capture Recapture (aSCR) methods and data from an acoustic survey using an array of 6 microphones to construct the first Peninsula wide population-density surface for this visually cryptic but acoustically active species. The analysis consisted of three stages. The first involved creating two sets of data from the original: one shows whether the species is present or not and the other indicates the density when the species is present. The second stage consisted of fitting a Hurdle Model to the data where the presence data is modelled using logistic regression and the density data is separately modelled using ordinary linear regression. The third stage involved combining the two models to estimate the expected density of the species. Confidence intervals were built using non-parametric bootstrapping. It was found that covariates explaining variation in occurrence were not the same as those explaining variation in density, suggesting that processes determining occurrence were not always those determining density. Of the environmental conditions examined, although predictive of occurrence, were generally poor predictors of A. lightfooti density. Presence of the Lightfoot’s moss frog was largely explained by topographic features and availability of water. In contrast. predictions of density were only weakly related to these same environmental factors and in some cases contradicting one another. The second part of this study produces the first Peninsula wide population density surface of A. 11'ghtfo0t1'. At the same time, it assesses the ability of using opportunistically collected presence-only records in combination with the higher quality density data to improve the estimation of expected population-density surface of A. Iightfooti. The presence-only records were constructed into a habitat suitability map using an ensemble of species distribution models. The habitat suitability map was then integrated in the modelling framework as a covariate in order to improve the estimation of expected population—(lensity surface of A. liglitfooti. However, the habitat suitability covariate resulted as being uninformative.
5

Ecological Consumer : A study on the factors influencing the ecological consumer / Ekologisk Konsument : En undersökning av faktorerna som påverkar den ekologiska konsument

Mörhed, Jakob, Karlsson, Jennica, Kulik, Stephanie January 2009 (has links)
<p> </p><p>Ecological issues are current topics which consumers face in every-day life. The growing awareness by the consumers that they can have an impact on protection of the environment, animals and their own health is the reason of the growing market of ecological products (Kinnear, Talor and Ahmed, 1974; Polonsky, 1994). According to the Swedish consumer agency the agricultural sector had increased highly since the 1990s. Hence the companies had increased its market activities significant under the last decade (Konsumentverket, 2007).</p><p>It appears more and more that the most important aspect for competitive positioning of companies providing ecological food is to understand the factors which drive consumers to purchase ecological food products. The KRAV label appears as an essential part of market ecological food. In this context it is very interesting to identify in which degree the consumer is affected by the third-party label KRAV.</p><p>The purpose of the paper is to identify information about the ecological consumer as well as the factors that influence consumers to buy ecological food products and in this context examine the awareness and importance of ecological labels, in Jönköping County.</p><p>The thesis is limited in its geographical area because the consumer survey is done in several cities in Jönköping County. The thesis considers general the ecological food industry and does not include other ecological industries such as clothes or furniture.</p><p>By studying former surveys and conducting a previous study a survey questionnaire was developed. 102 respondents from Jönköpings County were asked to fill in this questionnaire. The collected data were evaluated with the statistical program SPSS. Analysis of variance, correlation analysis and descriptive analysis were used.</p><p>The authors have got the impression that the ecological consumer in Jönköping County is mostly female and higher educated. The most important factors that influence the consumer positively to choose the ecological products are healthiness, environmental friendliness and better taste. If products do not include pesticides and are produced “animal friendly” it also influence the consumer positive. Negative factors that influence consumers are still a too high price, unavailability and bad/no information.</p><p> </p>
6

Ecological Consumer : A study on the factors influencing the ecological consumer / Ekologisk Konsument : En undersökning av faktorerna som påverkar den ekologiska konsument

Mörhed, Jakob, Karlsson, Jennica, Kulik, Stephanie January 2009 (has links)
Ecological issues are current topics which consumers face in every-day life. The growing awareness by the consumers that they can have an impact on protection of the environment, animals and their own health is the reason of the growing market of ecological products (Kinnear, Talor and Ahmed, 1974; Polonsky, 1994). According to the Swedish consumer agency the agricultural sector had increased highly since the 1990s. Hence the companies had increased its market activities significant under the last decade (Konsumentverket, 2007). It appears more and more that the most important aspect for competitive positioning of companies providing ecological food is to understand the factors which drive consumers to purchase ecological food products. The KRAV label appears as an essential part of market ecological food. In this context it is very interesting to identify in which degree the consumer is affected by the third-party label KRAV. The purpose of the paper is to identify information about the ecological consumer as well as the factors that influence consumers to buy ecological food products and in this context examine the awareness and importance of ecological labels, in Jönköping County. The thesis is limited in its geographical area because the consumer survey is done in several cities in Jönköping County. The thesis considers general the ecological food industry and does not include other ecological industries such as clothes or furniture. By studying former surveys and conducting a previous study a survey questionnaire was developed. 102 respondents from Jönköpings County were asked to fill in this questionnaire. The collected data were evaluated with the statistical program SPSS. Analysis of variance, correlation analysis and descriptive analysis were used. The authors have got the impression that the ecological consumer in Jönköping County is mostly female and higher educated. The most important factors that influence the consumer positively to choose the ecological products are healthiness, environmental friendliness and better taste. If products do not include pesticides and are produced “animal friendly” it also influence the consumer positive. Negative factors that influence consumers are still a too high price, unavailability and bad/no information.
7

AVAILABLE ENERGY AND SPECIES DIVERSITY: THEORY AND EXPERIMENTS WITH BEES (COMMUNITIES, FLOWERS, FORAGING).

WRIGHT, DAVID HAMILTON. January 1984 (has links)
A general biogeographic theory of insular species diversity, species-energy theory, is produced by replacing area in species-area models with a measure of available energy. Islands with more available energy support larger populations, which have lower extinction rates. Given similar immigration rates, islands with greater available energy are therefore expected to support greater equilibrium numbers of species. Assuming that total population size is proportional to energy supply, and that species-abundance distributions are lognormal and of similar form, the species-energy relationship is approximated by S = kEᶻ. Species-energy theory explains 70-80% of the variation in species number of angiosperms and of birds on such widely varying islands as Greenland and Jamaica. The effects of energy on the structure of a subalpine bee community in Colorado were investigated. As available nector declined, during mornings and over the season, foraging profitability for Bombus appositus (Hymenoptera: Apidae) decreased. This change was manifested by increased foraging trip durations: nector loads did not change. Total colony profits increased as colonies grew over the season, but profit relative to colony size declined, due to reduced profitability of individual foraging trips. These results support the hypothesis of resource limitation in this species. Assemblages of bees foraging on patches of flowers showed effects of energy availability on species composition and dynamics. Bees foraging in enriched patches had lower departure rates than bees in control patches, and, consequently, increased equilibrium numbers of individuals and species present per patch. Both behavioral and mechanical factors influenced departure rates. A species-specific arrival-departure rate model satisfactorily described the foraging assemblages and their response to enrichment. Experiments performed on 2 species of flowers with different corolla tube lengths demonstrated that bee species respond differently to resources of unequal availability, necessitating a species-level approach. Analogies with island systems are discussed. Energy is important to communities in general and bees in particular on a variety of scales. By implication, human resource diversion from natural ecosystems may have profound impacts on global diversity and extinction.
8

The classification of texture in remotely-sensed environmental imagery

Dikshit, Onkar January 1992 (has links)
No description available.
9

Communication networks and the implementation of biodiversity strategies

Zala-Larman, Catherine Elizabeth January 2001 (has links)
No description available.
10

Immune function and reproduction in the zebra finch Taeniopygia guttata

McPhie, Fiona Anne January 2000 (has links)
No description available.

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