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611.
臭氧(O3)是城市大气污染和气候变化促进的重要因子,对于城市大气污染与防治研究具有重要意义。本研究选取太原城区10个国控点O3日浓度变化,分析了其与相关气象因子(能见度、室外温度、室外湿度、风速和风向)的关系。研究结果表明,夏季O3浓度最高;春季O3浓度变化次之,冬季变化最小;城市新兴繁荣区和传统重工业区高浓度O3变化的时间跨度要明显高于过渡区域。城区O3和相关气象因子存在显著季节性变化特征。小波分析结果显示,城区O3时间序列相对较高能量的变化周期为主要以pp3浓度影响频率达50%;而夏季受此影响频率高达60%,秋季西西北风和西北北风对O3浓度的影响频率相近(约40%)。研究结果将有助于为北方城市大气污染防治提供理论参考和实践指导。 相似文献
612.
测定了27种取代苯类化合物在松花江江水中的生物降解性。采用量子化学MOPAC6.0-AM1法计算了化合物的分子量(MW)、生成热(Hf)、分子总表面积(TSA)及最高占有轨道能(EHOMO),结合辛醇/水分配系数lgP及酸解离常数pKa对其中22种化合物的BOD值进行多元线性回归分析,得到如下模型：BOD=105.73-0.439MW-0.076Hf-6.660lgP n=22,R2=0.821,SE=8.250,F=27.56,P=0.000应用所得模型对其余5个化合物的生物降解性进行了预测。只有一个化合物的相对预测误差大于20%,为20.8%.平均预测误差为12.4%. 相似文献
613.
614.
《Journal of Environmental Planning and Management》2012,55(1):1-15
The links between built form and environmental health are, as yet, inadequately understood. Risk is a formless and ambiguous phenomenon tightly embedded in the myriad pattern of land uses that generate it. Our research, which is founded on a contextualist notion of policy design, demonstrates the potential of innovative land use policy instruments (i.e. form-based codes, conditional use permits) to address risk. We model environmental risks from point and mobile sources in Southeast Los Angeles (SELA), a known air toxics hotspot. We compare risk contours before and after implementation of land use interventions. The use of innovative form-based codes for modifying built environments results in appreciable risk reductions around transportation corridors in SELA. Conditional use permits employing technological standards for commercial and light-industrial land uses also produce some risk reductions. This research suggests an untapped potential for land use planning instruments to address the environmental health impacts of built form. 相似文献
615.
《Journal of Environmental Planning and Management》2012,55(4):487-505
Pyrolysis1 biochar systems (PBS) could assist in meeting the Scottish Government's target of a 42% reduction in greenhouse gas emissions by 2020 relative to 1990. Drawing on literature review of land use and biomass availability in Scotland at present and in the future, and using established life cycle assessment models, we find that biochar could contribute between 0.4 and 2 MtCO2 equivalent (e) abatement per year in Scotland now (2009), increasing to between 1.4 and 4.2 MtCO2e/yr by 2030 and to between 1.5 and 4.8 MtCO2e/yr by 2050. The practicalities of such biochar deployment are explored further through spatial analysis. Through multi-criteria decision analysis, various factors are weighed up and traded-off against one another to show optimum locations for pyrolysis biochar facilities. The factors considered include proximity to sources (feedstock for biochar production), sinks (for biochar application), and proximity to transport infrastructure etc. Preliminary results show that most of the potentially suitable sites are around the central belt extending into Fife. 相似文献
616.
《Journal of Environmental Planning and Management》2012,55(3):398-411
Land use change is one of the main stress factors on ecosystems near urban areas. We analysed land use dynamics within Xochimilco, a World Heritage Site area in Mexico City. We used satellite images and GIS to quantify changes in land use/land cover (LULC) from 1989 to 2006 in this area, and a Markov projection model to simulate the impact of different management scenarios through to 2057. The results show an alarming rate of urbanisation in 17 years. LULC change runs in one direction from all other land use categories towards urban land use. However, changes from wetland or agricultural LULC to urban LULC frequently occur through transitional categories, including greenhouse agriculture and abandoned agricultural land. While urbanisation of natural land is often indirect, it is also effectively permanent. Active management aimed at protecting ecologically valuable habitats is urgently needed. 相似文献
617.
《Journal of Environmental Planning and Management》2012,55(1):88-102
Land subsidence attributable to the overuse of groundwater has resulted in severe damage in both urban and rural areas and in developed and developing countries. By incorporating the externality of groundwater use in aquacultural farming, we analyse how the government can mitigate the land subsidence levels without reducing the farmers’ profits, by both reusing the retired aquacultural land and through adjustments in the locations of the species currently being farmed in Tong-shi Township, Taiwan. The simulation results indicate that if the species with high profit can be sustainably raised and moved to aquacultural lands that are less sensitive to groundwater extraction, the total profit could exceed that without the regulation. 相似文献
618.
《Journal of Environmental Planning and Management》2012,55(1):1-23
In our research we investigated the optimal utilization of land resources for agricultural production in Tabriz County, Iran. A GIS-based Multi Criteria Decision Making land suitability analysis was performed. Hereby, several suitability factors including soils, climatic conditions, and water availability were evaluated, based on expert knowledge from stakeholders at various levels. An Analytical Hierarchical Process was used to rank the various suitability factors and the resulting weights were used to construct the suitability map layers. In doing so, the derived weights were used, and subsequently land suitability maps for irrigated and dry-farm agriculture were created. Finally, a synthesized land suitability map was generated by combining these maps and by comparing the product with current land use SPOT 5 satellite images. The resulting suitability maps indicate the areas, in which the intensity of land use for agriculture should increase, decrease or remain unchanged. Our investigations have revealed that 65676 hectares may be suitable for irrigation and 120872 hectares may be suitable for dry-farm agriculture. This indicates a substantial potential to satisfy the significantly increasing regional demand for agricultural products. The results of our research have been provided to the regional authorities and will be used in strategic land use planning. 相似文献
619.
《Journal of Environmental Planning and Management》2012,55(7):1043-1065
Redeveloping industrial land may run across obstacles, even within the same land-use designation, because previous industrial activities jeopardised the quality of the site. Contamination of soil and water is an example. Using a hedonic price method, this paper explores the effect of contamination and alternative remediation schemes on the industrial real estate property market. We consider the case of Porto Marghera in the Lagoon of Venice, a large and complex contaminated site listed on the Italian National Priority List (NPL). Our results indicate that the industrial real estate market rewards properties with a complete and certified clean-up scheme, while proximity to properties remediated with the ‘permanent safety containment measures’ negatively affects the selling price of nearby industrial properties. Characteristics of the properties, such as size, location, accessibility and other relevant economic indicators, do matter in explaining price differentials. 相似文献
620.
《Journal of Environmental Planning and Management》2012,55(6):920-936
Due to increases in population and migration to cities, the areas of urban land use are increasing. This study models the plausible future urban growth in the Mgeni catchment in KwaZulu-Natal, South Africa, using the SLEUTH Urban Growth Model (SLEUTH). The SLEUTH acronym stands for the input layers required for the model viz. Slope, Land use, Excluded areas, Urban Extent, Transport routes and Hillshade. The purpose of this study is to predict the scale and location of future urban growth, for use in hydrological impact assessment studies. SLEUTH was calibrated and applied to the Mgeni catchment to project future urban areas. The results revealed, when assessing the 95–100% probability class, that the Henley, Pietermaritzburg and Durban areas would experience the highest urban growth in the Mgeni catchment by the year 2050. It was concluded that the SLEUTH Model is suitable to account for the scale and location of future urban growth in the Mgeni catchment. 相似文献