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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

Vegetation of arable field margins in Breckland

Critchley, C. N. R. January 1996 (has links)
In the Breckland Environmentally Sensitive Area (ESA), farmers are encouraged to manage arable field margins to conserve arable plant communities using uncropped, cultivated field boundary strips ("uncropped wildlife strips") (UWSs). This study aims to describe the vegetation ofUWSs and to carry out an ecological assessment against the ESA objectives. Data were collected from a sample ofUWS and normally cropped sites in three study areas between 1989 and 1992. Species richness and non-crop biomass were greater in UWS than cropped sites. Bromus sterilis became dominant in study area 1, and appeared to have a competitive effect on other species. In study area 2 cultivations were done less frequently and perennial Graminae spread and became abundant. In study area 3, Amsinckia micrantha showed greatest increase but no effect on other species was apparent. Weed ingress into adjacent crops was lower at UWS than normally cropped sites. ESA objectives were translated into ecological criteria which could be directly measured. Assessments by subjective expert opinion and using species autecological data were compared. Subjective data were collected by a postal questionnaire of experts. Indicator species for each criterion were identified by applying rule sets to a species-attribute matrix. Site values for each criterion were calculated, and overall site values (foci) assigned using a multiple criterion method. Subjective site assessments closely agreed with the site foci and also with three of the five criteria. Over four years, half the sites were above the threshold level which represented satisfying ofESA objectives. Multivariate analysis of variation in the vegetation, from the main dataset and from a second survey, showed sites with lower soil pH, K and total N were more successful. Those with many overhanging or broadleaved trees, or previously cropped with sugar beet were less successful. Some amendments to management prescriptions are recommended.
2

Organically modified mesoporous silicas as base catalysts for green chemistry

Mdoe, James Epiphan Gabriel January 2000 (has links)
No description available.
3

Street-level bureaucrats and agri-environmental schemes : the case of the FRCA project officer implementing ESA schemes in England and Wales

Cooper, Nicola Keppel January 1999 (has links)
No description available.
4

Studies on the pathogenicity of the entomopathogenic fungus Metarhizium spp. for the desert locust Schistocerca gregaria

James, P. J. January 1995 (has links)
No description available.
5

Symptom Based Classification of Environmentally Ill Patients: an Exploratory Study

Flanagan, William Joseph, 1963- 12 1900 (has links)
The purpose of the present study was to discern a symptom pattern for environmentally ill patients and provide evidence of the uniqueness of the resultant pattern to this population. Patients' environmental exposure was confirmed by the presence of toxins in the blood serum. All patients were administered psychological and physical symptom checklists, the Clinical Analysis Questionnaire, and a standardized intermediate neuropsychological examination. Results indicate a response pattern of symptoms including fatigue, low energy, weakness, poor concentration, poor memory, poor comprehension, headaches, aches and pains, clumsiness, sinus discomfort, mucus, eye problems, restlessness, and present performance inferior to prior level of functioning. Presence of these symptoms, as well as the uniqueness of this symptom pattern was supported by comparisons of the patient and standardization groups on the two standardized tests.
6

Developing A Protocol for An Environmentally Preferable Purchasing Plus (EPP+) Program at NASA Glenn Research Center

KONGTAWELERT, AMARIN 23 August 2010 (has links)
No description available.
7

Land use and vegetation change in agricultural landscapes : case studies from north-west Ireland

Power, James January 1996 (has links)
No description available.
8

The development and application of a battery for exploratory screening for neuropsychological deficits in children exposed to formaldehyde

Sauter, Diana Lee, January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1981. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 150-160).
9

A multiple criteria decision-making approach to establishing environmental and economic trade-offs in Pennine Dales agriculture

Barron, Nicola-Jo January 1997 (has links)
No description available.
10

The atomisation of rapeseed methyl ester in comparison with diesel fuel

Wang, Yawei January 2001 (has links)
No description available.

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