生态环境空间分级管控策略研究

生态环境空间分级管控是为了确保各级尺度下的生态环境空间充分发挥其生态服务功能所采取的管理控制手段与途径,同时给城市生态环境空间的管控提供依据,在不同尺度下,生态环境空间需按照不同精细度的管控方法和不同的土地空间单位进行分级,生态环境空间分级管控主要包括:省域尺度生态环境空间的管控、市域尺度生态环境空间管控和在主城区尺度下生态环境空间管控。通过3种尺度不同管控方法和策略的有效衔接,从宏观、中观和微观3个层次保证了生态规划的完整性和连续性,使生态系统服务真正发挥其价值。     

沂蒙山区不同覆被棕壤理化特征对径流溶解态氮磷输出的影响

以沂蒙山区的棕壤为例,利用野外原位模拟降雨试验,在分析荒草地、侧柏林、金银花、山楂园和花生地等5种典型覆被下棕壤坡地径流溶解态氮(DN)、磷(DP)输出特征的基础上,探讨了不同土地覆被类型下棕壤主要理化性质差异对径流DN、DP输出的影响.结果表明,在降雨强度(70 mm·h-1)、地形和植被覆盖度等条件较为一致的情况下...     

城市生活垃圾筛上物制备RDF及其燃烧特性研究

利用城市垃圾筛上物制备RDF可以实现垃圾处理的减量化和资源化。研究了北京市城市生活垃圾筛上物制备RDF的工艺条件,探讨不同成型压力、含水率以及助燃剂含量对RDF成型特性的影响,在此基础上研究添加CaO对其燃烧特性的影响。结果表明:含水率10%,成型压力1 MPa的RDF在加入1%的KClO4后成型较好,燃烧后残渣少。随着CaO添加量的增加,RDF燃烧SO2的释放量减少;而当CaO添加量大于2%时,HCl的释放量基本保持不变。在RDF中加入CaO可以将其中的氯元素和硫元素有效固定在残渣中,从而有效减少了酸性气体排放。     

动物源性食品中抗生素类污染物生物检测技术研究进展

抗生素类污染物在动物源性食品中的残留,因其对人类健康有着潜在危害而受到了广泛的关注,因此迫切需要建立快速、灵敏、高效、便捷的检测方法以便对其及时管理和防治.生物检测技术在实现对抗生素高灵敏度、高特异性、低成本、快速的检测方面具有很强的优势,主要包括微生物检测法、免疫分析法和生物传感器法等.本文基于免疫抗体和核酸适配体两...     

Temporal pessimism and spatial optimism in environmental assessments: An 18-nation study

The personal assessments of the current and expected future state of the environment by 3232 community respondents in 18 nations were investigated at the local, national, and global spatial levels. These assessments were compared to a ranking of each country's environmental quality by an expert panel. Temporal pessimism (“things will get worse”) was found in the assessments at all three spatial levels. Spatial optimism bias (“things are better here than there”) was found in the assessments of current environmental conditions in 15 of 18 countries, but not in the assessments of the future. All countries except one exhibited temporal pessimism, but significant differences between them were common. Evaluations of current environmental conditions also differed by country. Citizens' assessments of current conditions, and the degree of comparative optimism, were strongly correlated with the expert panel's assessments of national environmental quality. Aside from the value of understanding global trends in environmental assessments, the results have important implications for environmental policy and risk management strategies.     

Contribution of metabolites to mutagenicity during anaerobic biodegradation of fenitrothion

The contribution of fenitrothion and its microbial metabolites to the mutagenicity of a fenitrothion-containing solution was investigated during anaerobic biodegradation. Although a mixed culture of bacteria obtained from a paddy field degraded fenitrothion and reduced its concentration from 4.6 to 0.1 mg/l in 6 days, the indirect mutagenicity of the solution in Salmonella strain YG1029 increased. This increase was found to be partially due to amino-fenitrothion generated during the biodegradation. In addition, other unidentified metabolites contributed to the mutagenicity. In contrast, the indirect mutagenicity in strain YG1042, which was initially large because of fenitrothion, then decreased, and increased again. This increase in mutagenicity was also due to amino-fenitrothion and other unidentified metabolites. The mutagenicity in strains YG1029 and YG1042 decreased after day 6. The greatest contribution of amino-fenitrothion to the mutagenicity was calculated to be 73% and 61% in YG1029 and YG1042 on day 3 of incubation, respectively. That of unidentified metabolites was calculated at 49% and 61% on day 20, respectively. Therefore, because not all the toxic metabolites of a compound can be identified, it is important to evaluate the toxicity of a whole solution in a bioassay such as the Ames assay rather than deducing the toxicity of the solution from the combined toxicities of known metabolites.     

Melting and incineration plants of municipal waste. Chemical and biochemical diagnosis of thermal processing samples (emission,residues)

Control of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in emissions and thermal residues from incinerators has been a cause of public concern for more than one decade. Recently, several studies showed that other persistent organic pollutants (POPs) such as coplanar polychlorinated biphenyls (co-PCBs) also have dioxin-like activity and are released from incinerators. Therefore, the present study was aimed at making a risk assessment about dioxin-like activity in extracts of thermal waste residues (e.g. combustion gas; fly ash, slag) from incineration and melting processes in Germany and Japan. For this purpose, polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), coplanar polychlorinated biphenyls (co-PCBs), polychlorinated naphthalenes (PCNs) and polyaromatic hydrocarbons (PAHs) were analyzed by chemical analysis. Additionally, 2, 3, 7, 8-TCDD equivalents (EROD-TEQs) were determined by in vitro Micro-EROD bioassay using rat H4IIE hepatoma cells. EROD-TEQs could be correlated to I-TEQ values (from PCDD/Fs/co-PCBs) analyzed by chemical analysis resulting in a maximal sixfold higher estimate. Our study indicates minor influences of co-PCBs, PAHs and PCNs to the sum of dioxin-like toxicity in the extracts of thermal waste residues as determined here. Furthermore, we showed that the levels of dioxins and co-PCBs contained in slag from melting processes and bottom ashes from incineration processes were lower by 1-2 orders of magnitude than that in fly ash.     

Biological solubilization and mineralization as novel approach for the pretreatment of food waste

The performance of a garbage disposal system to solubilize and mineralize food wastes through biological solubilization was evaluated through the examination of the effects of operational conditions like water supply volume, water supply frequency and aeration on the amount of waste solubilized, mineralized and accumulated in the reactor. The biological solubilization process consisted of a solubilization reactor and a circulation tank. Food waste and fresh water were supplied into the solubilization reactor with support media. Wastewater from the solubilization reactor was discharged to the circulation tank and water in the circulation tank was periodically pumped back to the solubilization reactor. In case of the total food waste loading of 16 kg m(3-1) d(-1), little carbon (0-5.7%) accumulated in the reactor as long as the system was kept under aerobic condition through large volume of water supply (higher than 3.5 lh(-1)) or applying aeration in the circulation tank. However, 42% of the loaded carbon accumulated under anaerobic condition in low water supply (less than 1.8 lh(-1)). The rest of the waste was either solubilized or mineralized. The aeration in the circulation tank, therefore, was effective to provide similar solubilization and mineralization as the large volume of water supply. However, frequency of feeding at the large volume of water supply had no significant effect on the amount of waste solubilization and mineralization.     

A numerical method to predict flame fractal dimension during gas explosion

Accurate prediction of the flame propagation velocity during a gas explosion is essential to assess its consequences and to evaluate the risk level. The propagating premixed flame is self-turbulized due to the hydrodynamic instability, resulting in a fractal flame structure. It is therefore important for accurate prediction of flame speed to understand the flame’s fractal structure in detail and to predict its fractal dimension in particular. Numerical simulations of spherically-propagating flames have been previously attempted for such purposes. There are, however, difficulties to accurately predict the fractal dimension from the result of the numerical simulation of a spherically-propagating flame. In this study, we propose a method to easily predict the fractal dimension based on the numerical simulation of a planar flame. Planar flame propagation is simulated for different sizes of computational domain. The fractal dimension can be determined from the dependence of flame speed on computational domain size. The determined fractal dimension is favorably compared with previous experimental results.     

Recycling and consumption in Germany and Japan: a case of toilet paper

This paper compares the recycling attitudes of consumers in Germany and Japan, based on our nationwide questionnaires. We analyzed consumption behavior as well as recycling behavior in narrow sense, because it is important to study the former to see how the supply of recycled materials is balanced with the demand, particularly in Japan which exports little recycled materials. Toilet paper was adopted as a specific good for study, because consumers have options of buying virgin products and recycled products. It was found that German households pay for waste collection specifically and have higher recycling rates than Japanese households. On the other hand, similar figures in German and Japanese consumers were observed with regard to consumption of recycled products. Their purchasing criteria and preference on virgin and recycled products of toilet paper were examined by self-report and blind test with 2×2 experimental design for toilet paper (German versus Japanese, virgin versus recycled). Blind test showed that people prefer domestic and virgin products in both countries. Half of respondents rating virgin products guessed that the products contained recycled material. For Japanese, the material of the sample toilet paper, made from virgin pulp, seems to be a more determining factor than the nationality of products, i.e. made in Japan. On the other hand, for Germans, the domestic nature seems to be a more dominant factor than the material, i.e. made from virgin material. Canonical discriminant analysis in conjunction with logistic regression based on self-reporting data detected the characters ‘multiplied’, ‘appearance’ and ‘brand’ as major factors making the difference in preference between the two countries. The possible reasons causing the similarity and dissimilarity between the two countries are discussed with reference to the background history.