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11.
Principal Component Analysis (PCA) is a convenient tool used in aggregating the indicators of sustainable development and providing indices where different weights are assigned to the various indicators. There are, however, problems in interpreting of indices, especially if time series data are used. This study explores the feasibility of applying recent developments in PCA of time series using Philippine data. We present the comparative advantages of SPCA (Sparse Principal Component Analysis) relative to averaging of an adequacy/inadequacy index and PCA in index construction from various indicators of sustainable development in the Philippines in terms of usefulness and validity of indices being developed. SPCA can attain sparse and non-overlapping loadings without losing a large amount of explained variance compared to PCA. Because of the non-overlapping contribution of variables in SPCA components, indices can have clear and mutually exclusive meanings, facilitating interpretation. Even with a more complicated algorithm, reduced dimensions and simpler interpretation of indices justify the advantages of SPCA over PCA in index construction. The indices are interpreted in terms of the milestone of sustainability in the Philippines. The resulting indices provide an adequate summary of the sustainable indicators and evidence of the importance of leadership and political will in sustainable development.  相似文献   
12.
This paper computes the efficient air pollution abatement ratios of 30 regions in China during the period 1996–2002. Three air emissions (SO2, soot and dust) are considered. Data envelopment analysis (DEA) with a single output (real GDP) and five inputs (labour, real capital stock, SO2, dust and soot emissions) is used to compute the target emissions of each region for each year. The efficient abatement ratios of each region in each year are then obtained by dividing the target emission by the actual emission of an air pollutant. Our major findings are: 1. The eastern area is the most efficient region with respect to SO2, soot and dust emissions in every year during the research period. 2. The eastern, central and western areas have the lowest, medium and highest 1996–2002 average target abatement ratios of SO2 (22.09%, 42.23% and 57.58%), soot (26.19%, 56.34% and 66.37%) and dust (15.20%, 29.09% and 40.59%), respectively. 3. These results are consistent with the Environmental Kuznets Curve (EKC) theory, whereby a more developed area will use environmental goods more efficiently than a less developed area. 4. Compared to dust emission, the average target abatement ratios for SO2 and soot emissions (as direct outcomes of burning coal) are relatively much higher for all three areas.  相似文献   
13.
Protection of the water quality of Lugu Lake is important because it is a unique geographic and cultural resource. Not only point source pollution but also non-point source pollution contribute to degradation of water quality. A GIS-NPS model, with long-term hydrologic impact assessment (L-THIA), was used to evaluate long-term implications of land-use change impacts on non-point source (NPS) pollution. The land-use patterns of 1995 and 2005 were analysed to determine the changes in Lugu Lake watershed. A 30-year (1974–2003) precipitation dataset was used to estimate mean annual surface runoff and NPS pollutant loads. The contributions of different land-use categories to average annual runoff and NPS pollutant production were assessed with a unit contribution index (UCI). Results show loss of agricultural land (by 44.9%), while forest, grass/pasture and residential land increased to different degrees from 1995 to 2005. At the same time, annual average NPS pollutants, TN, TP, TSS and BOD loads all decreased, while heavy metal lead increased by 6.87%. The UCI formulated in this research was a more useful method to assess land-use impact on NPS pollutants than simple investigations of the percentage land-use change. Agricultural and residential land changes had more impact on NPS pollutants and were identified as the main source types. Suggestions on regulating land uses and management proposals for protecting lake water quality in Lugu Lake watershed are made.  相似文献   
14.
Regional land-use development projects are undertaken to protect water resources necessary for agriculture, energy and sustaining human life. The De?irmendere valley, in the province of Trabzon in the Black Sea region of Turkey, provides clean water to the city of Trabzon. The valley is part of the Silk Road from Asia to the Black Sea and contains historical monasteries such as Sumela, Kustul and Vazelon. However, over the years, misuse of the valley has caused freshwater, sea and environmental pollution. In an attempt to overcome these problems, a multilateral project, De?irmendere Vadisi Çevre Düzenlemesi (DEVAÇED), was launched in the region. This paper aims to provide information necessary for engineering projects within the region. Six villages, on both sides of the valley, were selected for this research and evaluated in terms of river basin utilization, topography, cadastral survey of property and ownership, and land readjustment improvements. The study found illegal and improper urbanization, including industrial facilities within the valley causing water pollution. Current cadastral base maps are not sufficiently accurate for engineering projects, and in some places buildings have been constructed on unstable soils that are susceptible to landslides. The research results have helped to generate important recommendations for rehabilitation of the river basin.  相似文献   
15.
By converting rural land into urban land, urbanization impacts on surface water quality, because cities produce more pollutants than farmlands, especially heavy metals. Ways to reduce urbanization impacts on water quality are now being highlighted worldwide. Considering that land use can be a source or sink in pollution runoff, an understanding of the relationship between urbanization and surface water quality, as well as effects of specific land uses on water quality, is crucial. Corresponding management and controlling steps can then be put forward towards non-point source (NPS) pollution control and urban sustainable development. China has experienced rapid urbanization, especially since the 1980s. However, the environmental impacts of this process are not fully investigated. Hanyang, Hubei Province was selected as a typical city to study the impacts of urbanization on lake water quality. Pearson's correlation analysis was performed to elucidate the correlation between different land uses and water quality indicators at both whole lake watershed and small catchment scales. The results indicated that land uses play different roles, either source or sink, in pollution flow processes. Bottomland had a negative and residential land a positive correlation to most water quality indicators, especially heavy metals. These proved to be indicative and crucial land uses in NPS pollution control. Finally, a strategy for regulating urban land uses is proposed for improving surface water quality in cities similar to Hanyang, in southern China.  相似文献   
16.
Monitoring agricultural sustainability requires careful summarising of indicators collected over time into indices representing facets of sustainability. When the number of variables exceeds the number of observations, interpretation of components from ordinary principal component analysis is usually difficult because of minimal or absence of sparsity among the loadings. This is also true for time series indicators that exhibit non-stationarity. A framework for the assessment of agricultural sustainability in a regional context is proposed. Sparse principal component analysis is used in constructing indices of agricultural sustainability that are then used to characterise the state of agricultural development and the dynamics of agricultural growth in Southeast Asia.  相似文献   
17.
The concept of sustainable cities is based on a development paradigm that recognizes that cities make an important contribution to social and economic development. System thinking, including hard and soft systems, can be used to provide a new perspective and tools to resolve questions. The 500-year-old heritage city of Udaipur in India, which has traditionally maintained the spirit of living in a sustainable manner, is now seeking sustainable development. This paper attempts to analyse the issues underlying sustainable development of Udaipur by applying CATWOE in order to comprehend the systemic elements of the city from a soft systems perspective.  相似文献   
18.
Yellow-dust storms (YDSs) have attracted increasing attention worldwide in the past decade. They can extensively disrupt socioeconomic activities and pose hazards to ecosystems, as well as to human health. In recent years, China has invested multi-billions of dollars to mitigate the impact of YDSs. However, the effectiveness of such YDS control programmes has rarely been evaluated. This research develops a causal model to quantify the environmental benefits of YDS control programmes in China, and further employs regional economic models to evaluate the ensuing economic impacts. The economic benefits generated from the YDS control programmes should remain stable across the years, primarily because of the multiplier effect of the investments, while the environmental benefits tend to decline over time. Our results suggest that YDS control programmes should consider stimulating local economic activities in addition to environmental goals in order to be cost-effective and sustainable in the long term.  相似文献   
19.
This paper presents results of a social cost–benefit analysis (CBA) of afforestation and soil moisture treatment of common lands under an integrated watershed development programme in Karnataka State, India. The aim of the study was to find out if soil moisture conservation and afforestation measures were justified in terms of economic efficiency. The assessment was undertaken by calculating the economic internal rate of return (EIRR) for five village common lands in two watersheds, Uparhalla and Chinnahagari, in central Karnataka. Focused group discussions were organised, using a semi-structured questionnaire and various stakeholders, including project implementing agencies, self help groups and other community-based organisations. The attractiveness of the programme in both watersheds for landless and land owners was high in three out of five sampled villages, with an EIRR ranging from 19% to 91%, while two villages in Chinnahagari watershed had extremely low EIRR, reflecting poor management of soil moisture and afforestation interventions and lack of institutional cohesion to sustain investments made to develop common lands. Therefore, the CBA conducted in the KAWAD project, except for two villages, shows that the investment made to develop common lands should yield substantial economic returns in the long term under a business as usual scenario.  相似文献   
20.
Distribution of industrial land use has a crucial influence on the regional environment. Nanfen is a developing industrial city affiliated with Benxi City, northeastern China. The suitability of industrial land use in Nanfen was evaluated to provide a scientific basis for industrial land-use planning and to minimise negative impacts on the local environment. Multi-criteria evaluation (MCE) within GIS was employed to derive a suitability map. The suitability map was compared with current industrial land use to identify areas for relocation of current industries. A total of 25.7% of the urban area in Nanfen was rated as suitable, 28.1% as somewhat suitable, 37.9% as unsuitable and 8.2% as most unsuitable. About 20.6% of the current industrial land was in suitable areas, 46.5% in somewhat suitable areas and 32.9% in unsuitable areas. We further verified the influence of selected factors on the suitability of industrial land use using a field survey. The results confirmed that industrial land-use relocation in Nanfen is required. This study uses ecological suitability evaluation as a basis for land-use planning and has implications for other industrial cities in northeast China that have similar environmental and ecological problems.  相似文献   
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