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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.
61

Obstacles facing BEE mining entrepreneurs during the growth stage

Ribane, Kgosimang Paul 03 June 2012 (has links)
The research aims to determine the obstacles that BEE mining entrepreneurs face at the growth stage of their business. The objective of the study is to gain insights into both internal and external factors, identify common obstacles which have not been identified elsewhere. The study was a qualitative study where twenty BEE mining entrepreneurs were interviewed. This entailed face to face interviews where themes were recorded and analysed. The interview entailed semi structured questions, where interviewees were asked about obstacles both in the external and internal environment, experienced during the growth stage. In terms of the results many obstacles were identified. The obstacles that BEE mining entrepreneurs faced at the growth stage, ranged from access to finance, regulatory obstacles, lack of skills, infrastructure, unrealistic expectations, economic factors and political factors.Copyright / Dissertation (MBA)--University of Pretoria, 2012. / Gordon Institute of Business Science (GIBS) / unrestricted
62

The Impact of Neonicotinoid Pesticides on Wild Bees in an Intensive Agriculture System

Gaudreault, Emma 28 September 2020 (has links)
Neonicotinoids are broad spectrum insecticides that are widely used to control many insect pests. In Ontario they are applied directly to the seeds of most corn and soy crops, after which they are incorporated into the tissues of the developing plant. While researchers have investigated how these insecticides impact honeybee health, much less attention has been given to the effects of neonicotinoids on wild pollinators. Ground nesting bees face exposure to neonicotinoids both in the soil, where they nest, as well as through other exposure routes (e.g, nectar and pollen of treated plants). I studied whether a higher concentration of neonicotinoid pesticides in soils within and near corn and soy crops is negatively associated with the abundance and diversity of ground nesting bees. To determine whether an association exists between soil neonicotinoid concentration and the abundance of associated ground nesting bee communities, I surveyed 16 eastern Ontario (mainly corn and soy) farms once per month from May to August, 2019, sampling the bee communities, soil pesticide levels, and floral resources. I found a significant interaction between the sampling period and neonicotinoid soil concentrations on ground nesting bee abundance. However, no similar relationship existed for an analysis with non ground nesting bees only. Specifically, I found that high concentrations of soil neonicotinoids were associated with lower expected bee abundances and low seasonal variation, a low concentration of soil neonicotinoids was associated with a high degree of seasonal variation, including spikes of relatively high expected abundances, and that sites with no neonicotinoids were associated with low seasonal variation and moderately high expected bee abundances. The number of floral units at a site was also positively associated with bee abundance, which is consistent with what has been reported in other studies. Diversity data are currently being processed off-site and unavailable at the time of publication. My results provide evidence that there exists the potential for higher risks of neonicotinoid seed treatments to ground nesting bees compared to the non-ground nesting community.
63

A Revision of the Bee Genus Epeolus Latreille of Western America North of Mexico

Brumley, Richard L. 01 May 1965 (has links)
Members of the genus Epeolus are small to medium-sized wasp-like bees which parasitize the colletid genus Colletes. Twenty-two species and two subgenera are recognized in this work .
64

Design and Evaluation of Convolutional Networks for Video Analysis of Bee Traffic

Vats, Prateek 01 August 2019 (has links)
Colony Collapse Disorder (CCD) has been a major threat to bee colonies around the world which affects vital human food crop pollination. The decline in bee population can have tragic consequences, for humans as well as the bees and the ecosystem. Bee health has been a cause of urgent concern for farmers and scientists around the world for at least a decade but a specific cause for the phenomenon has yet to be conclusively identified. A normal hive inspection can be very disruptive for the bee colony, as the hive needs to be disassembled to visually assess hive health from the inside by collecting larvae and egg data. This work uses Machine Learning and Computer Vision methodologies to develop techniques to monitor hive health without disrupting the bee colony residing in the hive. Bee traffic refers to the number of bees moving in a given area in front of the hive over a given period of time. Bee traffic is related to forager traffic. Forager traffic is the number of bees moving out of the beehive. Forager traffic is a crucial factor in determining and monitoring food availability, food demand, colony age structure, the impact of pesticides, etc. on beehives. This work focuses on estimating bee traffic levels in a given hive and associate this information with data collected through manual beehive inspections.
65

Land Redistribution and its impact on Agri-BEE: A case study of Calcom PTY, Barberton, Mpumalanga, South Africa

Lepheane, Tumelo Justice 28 February 2007 (has links)
Student Number : 0006374W - MA research report - School of Sociology - Faculty of Humanities / The principal aims of the study were to evaluate the objectives, achievements and limits of the South African land redistribution programme as from 1994-2005. This study placed particular emphasis on evaluating the period commencing in 1999 until 2005 since this period is credited for formally aligning Land redistribution with broader objectives of Broad Based Black Economic Empowerment (BBBEE). As a result of the aforementioned this study also aimed to evaluate the extent to which the Land Redistribution for Agricultural Development (LRAD) reflects the broader objective, vision and aspirations of BBBEE and Agri-BEE. The latter analysis was based on an LRAD case study called Calcom PTY LTD in Barberton; Mpumalanga, South Africa. To extrapolate the data required for the attainment of the aims of the study, a qualitative research strategy which was based on a case study approach was utilised. This culminated in the choice of Calcom which is an LRAD project in order to further the analysis of the study. This enabled the study to develop a conceptual account of policy developments in the post-1999 period which saw BBBEE becoming a permanent feature of the South African land redistribution programme. Consequently a number of theories were used to account for changes that were made in the post-1999 period, namely the Neo-Classical, radical political economy, conceptual approaches to policy making and theories of development. This study argues that these changes are important for facilitating land redistribution to black people. However, without ensuring the availability of basic prerequisites for the emergence of black commercial farmers, such as skills developments, infrastructural support services, postsettlement support and access to finance and credit; the achievements and bias of LRAD towards black commercial farmers in theory will not have any impact on the broader vision of deracialising the Agri-economy in practice. Instead it will exclude the majority of poor black South Africans it ought to help, while empowering a few well resourced South Africans.
66

The American dream and other fiction

Hollingsworth, Raquel 30 April 2011 (has links)
The American Dream and Other Fiction is a collection of four magical realism short stories focusing on the idea of revealing the human condition through the ridiculous. Although the four stories are written independently of each other, they all carry the similar motif of entrapment. This collection also remarks on the growing absurdity of American capitalism and political correctness. The critical introduction analyzes techniques of verisimilitude in magical realism by traditional authors as well as the techniques of more contemporary magical realists. The collection focuses specifically on the techniques of frontloading and authoritative voice.
67

Evaluating the Success of Ontario Roadside Restorations - An Ecosystem Approach

McHaffie, Mara January 2021 (has links)
Ecological restoration, or assisting the recovery of damaged ecosystems, is recognized as a crucial activity for reversing biodiversity loss across the globe. Roadside rights-of-way may be suitable areas for the restoration of endangered grassland communities, because they occupy significant areas of underutilized land, are managed as early successional plant communities, and may serve as corridors for wildlife movement and gene flow. However, though many roadside restoration projects have been undertaken in North America, few studies have evaluated their long-term success and most monitoring is narrow in scope. True restoration includes restoring an appropriate species composition, vegetation structure and ecosystem functions, and thus these ecosystem components must be measured when evaluating success. I assessed the plant community, bee community, soil carbon and plant-fungal relationships at roadside restorations of various ages along three major highways in Southern Ontario and compared these measures to unrestored roadsides and reference sites. I found that roadside restorations successfully increased native plant richness, though not to the level of a remnant grassland. Bee communities varied mostly by highway rather than site type, though bee abundance was positively correlated with plant diversity and bare ground. Soil carbon in roadside sites was similar to that of a remnant grassland but did not differ among restored and control sites. Plant growth response to arbuscular mycorrhizal fungi collected from roadside sites varied depending on the site and showed a weak negative correlation with site age. Taken together, these results suggest that roadside restoration can benefit some ecosystem components, but simply seeding native plants along roadsides may not be sufficient for improving ecosystem function. This study highlights the importance of evaluating success in a comprehensive manner that includes multiple ecosystem components. / Thesis / Master of Science (MSc) / Ecological restoration is crucial for reversing global biodiversity loss. Roadsides may be suitable for the restoration of grassland ecosystems, but few studies have comprehensively evaluated the long-term success of roadside restorations. I assessed the plant community, bee community, soil carbon and plant-fungal relationships at roadside restorations along three Southern Ontario highways and compared these measures to unrestored roadsides and a remnant grassland. Restoration increased native plant diversity, though not to remnant levels. Bee communities varied mostly by highway, though bee abundance was positively correlated with plant diversity. Soil carbon in roadside sites was similar to the remnant but did not differ among restored and unrestored sites. Plant response to soil fungi collected from roadside sites varied significantly by site. Thus, roadside restoration can benefit some ecosystem components, but more intervention may be required to restore ecosystem function. This study highlights the importance of evaluating restoration success in a comprehensive manner.
68

The culture of bee forage crops /

Pan, Zhiliang 01 January 1997 (has links) (PDF)
No description available.
69

Study of Two Species of Bees (Apis mellifica) and Three Types of Beehives In and Around Chulumani (Prov. Chapare)

Pardo, Jose Cruz 01 January 2000 (has links) (PDF)
In order to improve the diet of the comunarios of Chulumani, and to expect a better production of honeybee; it has been introduced the Apis mellífica cárnica queen in Apis mellífica scutellata colonies. It was also carried out comparative tests among beehives Langstroth, Schirmer and Dadant. The nucleus “S” was only used as an introduction of queens, and the nucleus “M” and “K” were utilized for the development of the colony (submúltiplos of the beehive Schirmer). The study was carried out totally at random with the experimental design with factorial arrangement, and the meaning of the comparative analysis it was determined by the test of Dunnett. As a result of the substitution of queens more docile colonies were obtained with yields of honey of 22-26 Kg/beehive; being the beehive Schirmer the one that gathered the best size, weight and geometric space similar to which the bees develop in natural form. This way, it has been obtained a technically and economically viable beekeeping with carniolan bees in beehives Schirmer.
70

The etiological agent of hairless-black syndrome of the adult honey bee, Apis mellifera L., and certain factors influencing its infectivity /

Rinderer, Thomas E. January 1975 (has links)
No description available.

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