Impacts of deforestation on mosquito community dynamics
File(s)
Author(s)
Brant, Hayley
Type
Thesis
Abstract
Human-induced land use changes, including deforestation, agricultural encroachment and urbanisation, have caused widespread change in the global distribution of organisms and caused considerable declines in biodiversity through loss of habitat. Oil palm is one of the most rapidly expanding crops in Southeast Asia, but the impact of this crop on mosquito distribution, behaviour and exposure potential has been poorly explored. Understanding these factors is essential for developing, optimising and evaluating novel control measures aimed at reducing disease-transmission. This thesis explored the effect of land use change along an anthropogenic disturbance gradient (primary forest, disturbed forest, highly disturbed forest, oil palm plantations and rural housing estates) in Sabah, Malaysia. The community composition of anthropogenic mosquitoes was separated across land use, with the biggest difference seen between primary forest and oil palm plantations. This was largely driven by medically important mosquitoes attracted to oil palm plantations. Differences in community composition were also seen in areas of rural housing in comparison to primary and disturbed forest sites, due to a high presence of the dengue vector, Stegomyia albopicta, in housing areas. A higher abundance of anopheline vectors were found landing on humans in the disturbed forest and oil palm plantations then primary forest. This thesis found no difference between highly disturbed forest and oil palm plantation sites. This thesis also investigated the host-seeking behaviour of simian malaria vectors, by carrying out human landing catches at ground and canopy level across land use. Results demonstrated the potential ability of one of the vectors, Anopheles balabacensis, to transmit the simian malaria (Plasmodium knowlesi) between canopy-dwelling simian hosts and ground-dwelling humans, and that anthropogenic disturbance increases the abundance of the disease vector. Finally, this thesis investigated the use of different marking methods and the need for an improved dispersal experiment to be carried out.
Version
Open Access
Date Issued
2015-09
Date Awarded
2016-03
Copyright Statement
Attribution NoDerivatives 4.0 International Licence (CC BY-ND)
Advisor
Mumford, John
Ewers, Robert
Sponsor
Natural Environment Research Council (Great Britain)
Grant Number
NE/I527902/1
Publisher Department
Centre for Environmental Policy
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)