Ecological engineering for sustainable AIT Eco-Campus : diversification of wetland eco-services via water quality-biodiversity nexus | |
| Author | Mukhtar, Hussnain |
| Call Number | AIT Thesis no.EV-15-07 |
| Subject(s) | Urban ecology--Thailand Wetlands--Thailand Biodiversity--Thailand City planning--Thailand--Environmental aspects |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Environmental Engineering and Management |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. EV-15-07 |
| Abstract | The thesis deals with the concept of an urban ecologically engineered system, called Eco-City (Sustainable City), which offers numerous water-related eco-services to its inhabitants, and where, among other issues, wastewater is considered to be a valuable resource to be used for a sustainable enhancement and diversification of multiple eco-services. The eco-services comprise: water quality improvement (health risk mitigation), aesthetically appealing landscaping, aquaculture (fish, taro tubers, lotus seeds and stems, Spirulina sp. biomass), irrigation, and biodiversity. The AIT campus with its wetlands (pond, canals, lake, marshlands) is considered in the framework of the thesis to be a prototype of a developing Eco-City. Microphytes (microalgae) and macrophytes (water plants) in the selected wetlands were found to play a significant role in inactivation of E. coli entering wetland water with seeped sewage. E. coli concentration decreased from 9,300 to 23 MPN/100ml by enhancing diverse macrophyte density which increase rotifer concentration (Brachionus sp.,Philodina sp., Cephalodella sp.) from 23 to 450 individuals/L. E. coli inactivation experiments in microphyte presence were undertaken with two microphyte species, Selenastrum sp. and Spirulina sp. belonging to two very different microphyte groups, green algae (Chlorophyta) and Cyanobacteria ("blue-green algae"), respectively. It was shown that a linear relationship existed between E. coli die-off rate and microphyte concentration (Chl. a) concentration (p<0.05), in which die-off rate increased (Selenastrum sp.: 0.20 to 1.65 day-1; Spirulina sp.: 0.14 to 0.77day-1) with microphyte concentration increasing from 50 to at least up to 250 μg/L. Cyanobacterium Spirulina sp. at very high concentration of 200-400 μg/L was found to be a persistent dominant species (98%) in the AIT fountain/library pond system over the entire study duration, irrespective of the season. Such measures as the introduction of considerable number of macrophytes (surface coverage of up to 13%) and partial water change (15% by volume, July 2014) were not successful in either reducing algal concentration or increasing microphyte diversity. The only viable solution is now believed to be complete change of water and flushing out existing 'infectious' Spirulina. The research findings prove to be of great significance for the concept of Eco-City, since the different microphyte behaviors can be used under different and variable conditions of Eco-City, as these can be used in the AIT Eco-Campus wetlands providing for eco-engineered robustness, ecological stability and urban sustainability of wetlands. Application of the principles of eco-engineering to the main campus wetland, Fountain pond connected to Library pond via a canal, proved to be a successful landscaping intervention, which dramatically enhanced aesthetic image of this most visited and prominent area of the campus. The macrophytes of nearly eight different species attract additional biodiversity (most prominently, water birds) further enhancing appeal and the image of the AIT campus. The macrophyte-related landscape intervention solved the problem of contaminated surface water, which for years presented significant health risks to the AIT community, particularly through the fountain spray. |
| Year | 2015 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Energy and Climate Change (Former title: Department of Energy, Environment, and Climate Change (DEECC)) |
| Academic Program/FoS | Environmental Engineering and Management (EV) |
| Chairperson(s) | Shipin, Oleg V.; |
| Examination Committee(s) | Annachhatre, Ajit P.;Thammarat Koottatep; |
| Scholarship Donor(s) | Asian Institute of Technology Fellowship; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2015 |