How to minimize the negative impacts on Bundala National Park due to irrigation development of the Kirindi Oya River Basin

The environment is an important water user, and one that often finds itself at the bottom of the list of priorities when supplies become scare. This research studied how the needs of wetlands can coexist in parallel with irrigation demands and other human activities. Sri Lanka is a signatory to the Convention on Wetlands of International Importance for Migratory Waterfowl, known as the Ramsar Convention and Bundala Lagoon was declared Sri Lanka’s first Ramsar site, a wetland of international importance for migratory waterfowl, in 1990, because of its high bird species richness. The delicate ecological balance of these lagoons will be severely affected by the on-going Weheragala Reservoir project, which is designed to divert excess water from Manike Ganga River basin to Kirindi Oya River basin and the Malala Oya River basin development project. The main negative impacts are eutrophication, accumulation of pesticides and insecticides in the lagoons and siltation, and that lagoons will be converted to fresh water bodies. This research studied how to minimize these negative impacts using social, economic and engineering tools. The research findings are useful for researches, policymakers and decision-makers, who must find opportunities to improve farmers’ incomes and national food production, while and at the same time ensuring sustainable management of wetland ecosystems in Sri Lanka.Length: pp.1-6WetlandsLagoonsHabitatsIrrigated farmingEnvironmental degradation

Laser processing of solution based antimony doped tin oxide thin films

Antimony doped Tin oxide (SnO2:Sb, or ATO) is of interest as an alternative to Indium Tin Oxide (ITO) for large area optoelectronic applications. There is a particular interest in the potential for solution based coatings based on nanoparticulate suspensions of SnO2:Sb. However, solution processed films typically require a high temperature (~700⁰C) annealing step to achieve the desired electrical and optical properties. This is disadvantageous for applications that would benefit from low cost, low temperature/flexible substrates. As an alternative to conventional high temperature annealing, excimer laser processing can provide highly localized energy dissipation, and is an attractive technique to functionalise coated materials. Therefore the work presented in this thesis investigates the use of excimer laser processing to optimise the electrical and optical properties of solution deposited SnO2:Sb thin films for use in electroluminescent display devices. Thin films of SnO2:Sb were deposited using dip coating, inkjet printing and the spin coating technique. By varying the numbers of spin coatings deposited, a series of samples were prepared on Eagle XG glass substrates with different thicknesses of SnO2:Sb (ranging from 0.2 μm to 1.4 μm). The initial sheet resistance, optical transmission and crystal structure of the deposited films was studied. The films were subsequently post processed using three different annealing techniques: (i) Laser Processing: samples were laser processed in air to optimise the sheet resistance and optical transmission