Environmental & Physical Sciences

Research Papers/Topics Environmental & Physical Sciences

Effects of variation in plant quality on densities and sizes of herbivores, primary and secondary parasitoids

Abstract: To investigate the effects of variation in host quality on densities and sizes of three levels of consumers, a cabbage-aphid-parasitoid foodweb was analyzed. Three close related cabbage populations were studied: Brassica oleracea var. gemnifera cv. Cyrus, a feral Brassica oleracea and a wild cabbage type Old Harry as source of variation in host plant quality. A field experiment were established in Wageningen, The Netherlands to measure the effects on densities of herbivores. Aphids...

The Spatial Distribution of Mosquitoes Related To the Environment on Rusinga Island, Western Kenya

Abstract: The SolarMal project on Rusinga Island, Western Kenya, aims to eliminate malaria by reducing the mosquito population, using a new developed mosquito trap which will be installed at all households on the island. The effect of the installed traps is monitored by sampling mosquitoes from randomly selected selected households on the island during the whole duration of the project. This thesis project aims to support the SolarMal project by performing spatial analysis to the distributio...

Determination of Neonicotinoid Residues in Hive Products from Kiambu and Nairobi Counties, Kenya

Abstract: Information on pesticide residue occurrence in hive products is scanty or lacking yet it is important so as to safeguard human health from effects of pesticides. The aim of the study was to identify and quantify neonicotinoid residues in hive products. The study was undertaken for 6 months between (March-August, 2015) at Kiambu and Nairobi Counties. The objectives of the study were to find out the pesticides used in the cultivation of crops, the frequency of use and the concentrati...

Crop diversification using improved sweet potato [Ipomoea batatas (L.) Lam.] varieties as an adaptation strategy to climate varibility by subsistence farmers in Taita Hills, Kenya

Abstract: A study on mechanisms used by subsistence farmers to cope with climate variability and change was conducted in the Taita Hills, Kenya from January 2014 to March 2015. Household surveys together with key informant interviews were used to collect data to assess farmers’ use of crop diversification as a strategy to cope with climate variability and change. Further there was an assessment of past crop records in relation to weather and climate data in the area. The study then assesse...

Development of Efficient Tools for Improved Surveillance of Vectors of Dengue and Chikungunya Fever.

Abstract: In the past 3 decades, arboviruses have become a major cause of re-emerging epidemic diseases in the world. Amongst the arboviruses, dengue and chikungunya fevers which are transmitted by Aedes spp have become more prevalent and have spread far beyond traditional areas of distribution - mainly in Africa and Asia - to cause severe morbidity, mortality, and economic harm. Currently control of these diseases solely depends on vector control as there is no treatment or vaccine. This ca...

Optimising a Resting box to enhance Adult Gravid Female Mosquitoe Auto-disseminate Larvicide in a Semi field

Abstract: Malaria control strategies that target adult mosquitoes are challenged by the emergence of insecticide resistance and behavioral changes of vectors. The conventional approach of applying larvicides is limited by high operational costs and inadequate knowledge of mosquito breeding habitats especially in rural African communities. This study developed a potential mosquito contamination site, assessed the potential of adult female Anopheles gambiae s.s to pick up fluorescent dye and a...

Assessment of information flow and ex-ante impact of potential cashew integrated pest’s management strategies for sustainable cashew production: the case of Tandahimba and Lindi rural distric

Abstract: This study was conducted to assess information flow and ex-ante impact of potential cashew IPM strategies for sustainable cashew production and marketing in Tanzania. Radio, extension workers, leaflets, posters, cashew development centres, on farm demonstrations and television were the identified information sources and communication pathways. Farm profit analysis of Potential IPM options were also quantified to find out the economic feasibility of cashew production at individual f...

Assessment of the Potential for Integration of Ecosystem Based Approaches and Local Indigenous Knowledge into Climate Change Adaptation in the Taita Hills, Kenya

Abstract: The integration of indigenous knowledge and science through and ecosystem based adaptation provides a basis for the formulation of culturally acceptable and sustainable adaptation practices. This study aims to determine sustainable climate change adaptation strategies for the Taita Hills in Kenya and assess their potential for integration with ecosystem based adaptation. It uses a mixed methodology that involves literature review, participatory methods and household surveys. As a r...

Assessment Of Conservation Agriculture As An Adaptation Option To Climate Change In The Taita Hills, Kenya

Abstract: Climate Change and Variability affects water supply and food security, especially in developing countries where many small-scale farmers rely on rain-fed agriculture for food production and as a main source of livelihood. The extent of the effects of climate change and variability on these small-scale producers largely depends on their level of adaptation, adaptive capacity, exposure and vulnerability. This study evaluates the effectiveness of Conservation Agriculture (CA) as a pos...

Agro-ecosystems’ resilience to damage: determination of index of susceptibility to climate change in mount kilimanjaro, Tanzania.

Abstract: This paper assesses maize-coffee-banana agro-ecosystems’ resilience to damage as well as computing the social-ecological vulnerability index to climate change on the southern slope of Mount Kilimanjaro in Tanzania. The study focused on identifying agronomic practices and assessing their impacts on agro-ecosystems’ resilience; examine the socio-economic status of the farmers in the region and its impacts on agro-ecosystems; and examine the agro-ecosystems’ natural resilience a...

Assessment of Adoption of Watershed Management Approaches for Sustainable Constituency Development Fund Projects in Funyula Constituency, Kenya

Abstract: Management of the natural resource of a drainage basin primarily for the production and protection is considered essential for soil and water conservation. Despite an increase in CDF allocations, watershed management approaches are not integrated in local development projects to realize sustainability. The study assessed the need and ways of considering watershed management approaches in CDF projects. Key objectives included to determine the relative importance of factors that infl...

Socio-economic importance of Liriomyza leaf miners of vegetable crops in Tanzania: a study of farmers’ knowledge, attitudes and Practices in Arumeru and Moshi-Rural Districts

Abstract: This study assessed the socio - economic importance of Liriomyza Leafminers (LMF) of vegetable crops in Northern Tanzania focusing on farmers’ knowledge, attitude and practices towards management of this insect pest in their fields. A total of 117 households were interviewed for primary data collection. Desk study was used for secondary data collection. Findings revealed that majority of respondents were educated up to primary level and lived in households with 1 – 10 individua...

Mortality Rate of Houseflies Exposed to Some Selected Insecticide to Some

Abstract Houseflies are pest in homes, dairies, barns, poultry houses, recreation areas and food processing sites. The study is to evaluate the susceptibility of Musca domestica to deltamethrin, cypermethrin and DDVP insecticides. Topical bioassay was used to perform adulticidal test, while dipping method was used for larva and pupa, different concentrations were used which ranges from 0.5ml/L-10.0 ml/L for larvae and pupae while 5.0 µL/fly-50.0 µL/fly was used for adult Musca domestica. Th...

Optimization and Screening of Extracellular Enzymes produced by Pseudomonas Aeruginosa during LDPE degradation

ABSTRACT Plastics are synthetic polymers made by chains of carbon atoms with hydrogen, oxygen, nitrogen, Sulphur built around the carbon chains (Shah et al., 2008). These polymers are involved in every domain of our lives ever since its production began from the year 1950’s, plastics have been produced at an augmented rate to meet day to day demands of the entire world. Accumulation of plastic waste in the environment causes chemical pollution when methods like incineration are used to get ...


451 - 465 Of 1971 Results
@