Environmental impact assessment of structural flood mitigation measures by a rapid impact assessment matrix (RIAM) technique: A case study in Metro Manila, Philippines.
ABSTRACT In recent decades, the practice of environmental impact assessment (EIA) in the planning processes of infrastructure projects has created significant awareness on the benefits of environmentally sound and sustainable urban development around the world. In the highly urbanized megacities in the Philippines, like Metro Manila, high priority is given by the national government to structural flood mitigation measures (SFMM) due to the persistently high frequency of flood-related disasters, which are exacerbated by the on-going effects of climate change. EIA thus, should be carefully and effectively executed to maximize the potential benefits of the SFMM. The common practice of EIA in the Philippines is generally qualitative and lacks clear methodology in evaluating multi-criteria systems. Thus, this study proposes the use of the rapid impact assessment matrix (RIAM) technique to provide a method that would systematically and quantitatively evaluate the socio-economic and environmental impacts of planned SFMM in Metro Manila. The RIAM technique was slightly modified to fit the requirements of this study. The scale of impact was determined for each perceived impact, and based on the results, the planned SFMM for Metro Manila will likely bring significant benefits; however, significant negative impacts may also likely occur. The proposed modifications were found to be highly compatible with RIAM, and the results of the RIAM analysis provided a clear view of the impacts associated with the implementation of SFMM projects. This may prove to be valuable in the practice of EIA in the Philippines.
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ABSTRACT: In the spring of 1998, 24-h time series and synchronization of vertical profiles of NO(3)-N, NO(2)-N, NH(3)-N, PO(4)-P, chlorophyll a, suspended substance, salinity, temperature and other chemical parameters were taken at 10 stations in the Pearl River estuary in order to analyze the status and characteristics of nutrients and eutrophication. The results indicated that dissolved inorganic nitrogen (DIN) mainly came from the four river channels in the main estuary, and NO(3)-N was the main form of DIN in most area. The concentration of DIN was general above 0.30 mg l(-1) in the estuary, and more than 0.50 mgl(-1) in most part. Phosphate from four river channels was not the main sources, but land-based sources from the area near Shenzhen Bay or along the estuary were obvious, and other land-based sources outside the estuary brought by coastal current and flood tide current were also the main contributions. The concentration of phosphate was generally about 0.015 mg l(-1) except the area near Shenzhen Bay. The ratio of N:P was generally high, and it was higher in the north than in the south. The highest ratio was higher than 300, and the lowest one was over 30. The concentration of chlorophyll a was about 0.8-7.8 mg m(-3), and turbidity and phosphate may be the main two limiting factors for algal bloom in the estuary. The concentration of nutrients decreased slightly in the past decade, but still stayed at a high level. The nutrients mainly came from domestic sewage, industrial wastewater, agriculture fertilizer and marine culture in the Pearl River estuary.Marine Pollution Bulletin 02/2003; 47(1-6):30-6. · 2.53 Impact Factor
Article: Investing in sustainable catchments.[show abstract] [hide abstract]
ABSTRACT: Catchments constitute logical units for management of the water cycle. Patterns of development uninformed by sustainability concerns have degraded catchment integrity and associated ecosystem functions, imposing largely unquantified costs. Ecosystem functions are central to sustainable social and economic progress; their protection or restoration may be the only sustainable form of investment in catchments. Despite growing use of catchment functions in some policy areas, a shortfall in awareness and pragmatic tools limits progress with policies and practical tools to support sustainable development in catchments, perpetuating damaging practices. This paper reviews methods of economic valuation of riverine systems. Valuation of ecosystem functions is revealed as particularly pertinent to sustainable development, as an indicator of the benefits of ecological processes to social and economic progress. A range of practical projects, targeted at restoration of riverine habitat in the UK with the intent of improving both river ecology and the social and economic advantages that flow from it, is also reviewed. Emerging principles and themes are discussed in terms of their potential contribution to policies and practices that promote sustainability. Review of these projects highlights the importance of planning at adequately broad scales--spatial, temporal and disciplinary--to identify integrated solutions, and to maximise community "buy-in" and total benefits. In several cases, economic analyses demonstrate strongly positive benefit-cost ratios stemming from habitat improvement. However, major reform of regulatory and economic instruments is needed to promote sustainable catchment development, since prevalent "perverse" incentives continue to degrade ecosystem functions. Measures to recognise and reward ecosystem service as legitimate outputs from agricultural land use constitute a particular priority. There is a need simultaneously to address both "big picture" structural adjustments and locally-appropriate solutions, from which clear local benefits flow. Pragmatic measures that contribute to systemic outcomes must also be attractive to local decision-makers and land managers, and yield benefits that ensure they are sustained once intervention ceases. Cost need not be a barrier, as current environmentally-damaging subsidies may instead be redirected towards sensitive land use and/or measures to protect biodiversity and ecosystem functioning, particularly where targeted upon habitat of disproportionate importance to functioning of catchments as whole systems. Internalisation of the costs of damage to ecosystem functioning will promote valuation of the natural capital of catchments as a primary resource for social and economic progress.Science of The Total Environment 06/2004; 324(1-3):1-24. · 3.26 Impact Factor