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1.
María L. Pignata Martha S. Cañas Hebe A. Carreras Liliana Orellana 《Environmental management》1997,21(5):793-801
Ligustrum lucidum Ait. f. tricolor (Rehd.) Rehd. in relation to atmospheric pollutants in Córdoba city, Argentina. The study area receives
regional pollutants and was categorized taking into account traffic level, industrial density, type of industry, location
of the sample point in relation to the street corner, treeless condition, and topographic level. Dried weight/fresh weight
ratio (DW/FW) and specific leaf area (SLA) were calculated, and concentrations of chlorophylls, carotenoids, total sulfur,
soluble proteins, malondialdehyde (MDA), and hydroperoxy conjugated dienes (HPCD) were determined in leaf samples. Sulfur
content correlates positively with traffic density and SLA correlates negatively with some combinations of the categorical
variables; MDA correlates positively with topographic level and total protein concentration correlates negatively with treeless
condition. On the basis of our results, traffic, location of trees, type of industry, situation of a tree with respect to
others, and topographic level are the environmental variables to bear in mind when selecting analogous sampling points in
a passive monitoring program. An approximation to predict tree injury may be obtained by measuring DW/FW ratio, proteins,
pigments, HPCD, and MDA as they are responsible for the major variability of data. 相似文献
2.
采用作者自行设计制作的混凝-微纳米气浮装置对炼化企业污水处理厂二沉池出水进行深度处理,考察了混凝剂投加量、工作压力、回流比和水力停留时间对气浮效果的影响,结果表明,最佳工艺参数为:混凝剂FeCl3 30 mg/L,工作压力0.2 MPa,回流比为20%,水力停留时间6 min。在此实验条件下,COD去除率为39.13%,SS去除率为51.85%,气浮出水COD<60 mg/L,达到了《污水综合排放标准》(GB 8978-1996)一级B标准。 相似文献
3.
Maria A. García-Valiñas Roberto Martínez-Espiñeira Francisco González-Gómez 《Journal of environmental management》2010,91(12):2696-2706
Using information on a basic or “lifeline” level of domestic water use obtained from a water demand function based on a Stone–Geary utility function, a minimum water threshold of 128 m3 per household per year was estimated in a sample of municipalities in Southern Spain. As a second objective, water affordability indexes were then calculated that relate the cost of such lifeline to average municipal income levels. The analysis of the factors behind the differences in that ratio across Andalusian municipalities shows that the relative cost of purchasing the lifeline appears inversely related to average income levels, revealing an element of regressivity in the component of water tariffs affecting the least superfluous part of the household’s consumption. The main policy recommendation would involve redesigning water tariffs in order to improve access for lower income households to an amount of water sufficient to cover their basic needs. The proposed methodology could be applied to other geographical areas, both from developed and from developing countries, in order to analyze the degree of progressivity of the water tariffs currently in effect and in order to guide the design of more equitable regulatory policies. 相似文献
4.
Suescún Diego Villegas Juan Camilo León Juan Diego Flórez Claudia P. García-Leoz Vanessa Correa-Londoño Guillermo A. 《Regional Environmental Change》2017,17(3):827-839
Regional Environmental Change - Mountain ecosystems provide key services to a large portion of the population in the tropics. However, they are particularly vulnerable to regional environmental... 相似文献
5.
Jiménez MA Martín-Valdepeñas JM García-Talavera M Martín-Matarranz JL Salas MR Serrano JI Ramos LM 《Journal of environmental radioactivity》2011,102(11):995-1007
In the frame of an epidemiological study carried out in the influence areas around the Spanish nuclear facilities (ISCIII-CSN, 2009. Epidemiological Study of The Possible Effect of Ionizing Radiations Deriving from The Operation of Spanish Nuclear Fuel Cycle Facilities on The Health of The Population Living in Their Vicinity. Final report December 2009. Ministerio de Ciencia e Innovación, Instituto de Salud Carlos III, Consejo de Seguridad Nuclear. Madrid. Available from: http://www.csn.es/images/stories/actualidad_datos/especiales/epidemiologico/epidemiological_study.pdf), annual effective doses to public have been assessed by the Spanish Nuclear Safety Council (CSN) for over 45 years using a retrospective realistic-dose methodology. These values are compared with data from natural radiation exposure. For the affected population, natural radiation effective doses are in average 2300 times higher than effective doses due to the operation of nuclear installations (nuclear power stations and fuel cycle facilities). When considering the impact on the whole Spanish population, effective doses attributable to nuclear facilities represent in average 3.5 × 10−5 mSv/y, in contrast to 1.6 mSv/y from natural radiation or 1.3 mSv/y from medical exposures. 相似文献
6.
Chun Chen Yuzheng Wang Yuanyuan Zhang Xiaoxiu Lun Chengtang Liu Yujing Mu Chenglong Zhang Pengfei Liu Chaoyang Xue Min Song Can Ye Junfeng Liu 《环境科学学报(英文版)》2019,31(6):316-326
The efficient maintenance of the activity of excised branches is the powerful guarantee to accurately determine gas exchange flux between the detached branches of tall trees and the atmosphere. In this study, the net photosynthetic rate(NPR) of the excised branches and branches in situ were measured simultaneously by using two photosynthetic instruments to characterize the activity of the excised branches of Phyllostachys nigra. The ratio of normalized NPR of excised branches to NPR in situ was used to assess the photosynthetic activity of detached branches. Based on photosynthetic activity, an optimal hydroponics protocol for maintaining activity of excised P. nigra branches was presented:1/8 times the concentration of Gamborg B5 vitamin mixture with p H = 6. Under the best cultivation protocol, photosynthetic activity of excised P. nigra branches could be maintained more than 90% within 6 hr in the light intensity range of 200–2000 μmol/(m2·sec) and temperature range of 13.4–28.7°C. The nitrogen dioxide(NO2) flux differences between in situ and in vitro branches and the atmosphere were compared using double dynamic chambers.Based on the maintenance method of excised branches, the NO2 exchange flux between the excised P. nigra branches and the atmosphere(from-1.01 to-2.72 nmol/(m2·sec) was basically consistent with between the branches in situ and the atmosphere(from-1.12 to-3.16 nmol/(m2 sec)) within 6 hr. Therefore, this study provided a feasible protocol for in vitro measurement of gas exchange between tall trees and the atmosphere for a period of time. 相似文献
7.
The utilization of waste products as valuable materials was a technical imperative for waste management. In this study, the cost-effective attapulgite/carbon(APT/C) composite was developed for wastewater treatment using waste hot-pot oil as a carbon precursor through a facile one-step calcination process. The APT/C composite prepared at 300°C exhibited the excellent adsorption capacity and rapid equilibrium rate over a broad p H range for the removal of various pollutants. More importantly, the removal ratios of the composites toward Methyl Violet and tetracycline still remained 77.6% and 60.2% of the initial adsorption capacity after ten adsorption–regeneration cycles via a facile thermal regeneration strategy, respectively.Beyond all doubt, this research provided a feasible and economical way for the sustainable utilization of waste hot-pot oil in wastewater treatment, achieving the concept of disposal waste with waste and recycling. 相似文献
8.
中国生态用地及生态系统服务价值变化研究 总被引:16,自引:1,他引:16
生态用地具有重要的生态系统服务功能,在维护生态平衡、保障国土生态安全、应对全球气候变化中具有特殊地位。论文在总结国内研究学者有关生态用地研究成果的基础上,从生态系统服务功能入手,界定了生态用地的概念,根据生态干扰度构建了生态用地分类体系,并将生态用地分类与土地利用分类进行衔接,对全国生态用地的生态系统服务价值进行了评估,分析其特征及规律。研究表明:1)广义的生态用地是指能发挥供给、调节、支持生态系统服务功能,以及对维持区域生态平衡和调节全球气候具有重要作用的土地类型;2)依据“生态干扰度”构建了生态用地分类体系,将生态用地分为3个一级地类、5个二级地类和31个三级地类;3)2012年全国生态用地的生态系统服务价值为280 483.80亿元,呈现“西高、中次、东低”空间格局。2009—2012年全国生态用地的生态系统服务价值整体呈下降趋势,变化幅度空间分布差异较大,呈现“中增、东西减”的格局特点;2009—2012年全国生态用地各项生态系统服务功能受到损失,呈下降趋势,生态系统稳定性不容乐观。 相似文献
9.
石油污染地的土壤修复技术 总被引:1,自引:0,他引:1
对石油污染土壤的各类修复技术进行了总结和归纳,并对各项技术的优缺点加以比较,提出了一套石油污染地生态恢复的流程。 相似文献
10.