基于结构方程模型的广州城市社区居民出行行为

基于行为主义的视角,从微观的社区层面研究城市居民的出行行为。选取广州市的3 个城 市社区作为案例,以218 个样本数据库为基础,根据研究的侧重点不同分别建立两个结构方程模 型,拟合各变量之间的路径关系。其中居民出行选择的结构方程模型重点分析居民属性、居住 区位与居民出行目的、出行时间、出行方式等出行偏好之间的关系。居民出行决策的结构方程 模型则模拟居民的出行决策过程。结果显示：居民之间由于自身属性不同在出行选择和出行偏 好上存在差异,居民出行行为中居民属性和居住区位是根本,出行目的是关键,居民出行行为可 以概括为“属性决定目的,目的影响行动”。此外,居民的出行行为有其复杂的作用机制和决策 路径,居民的出行决策过程可以解读为性别决策子系统、年龄决策子系统、收入决策子系统和居 住区位决策子系统等4 个决策子系统,各子系统中路径作用的不同使居民属性和居住区位对居 民出行决策产生多重多向的效应,在复合系统的影响下城市社区居民表现出差异化的出行 行为。     

社区居民参与旅游的影响因素研究——基于兴文石海的Logistic回归分析

为了找出旅游地社区居民参与旅游的影响因素,通过对兴文石海地质公园相关社区的居民进行调查,对调查数据进行Logistic回归分析,得出了从事旅游相关行业的比较效益、居民参与旅游的主观愿望、优先在旅游企业获得工作机会的意识和参与技能等几个影响当地社区居民参与的因素。在此基础上,结合调查了解的情况,对如何提高社区居民的参与程度作了简单的探讨,并提出以下几种方法:提高旅游业的比较效益、提高旅游业的吸引力以提高居民参与希望、提高居民优先获得工作机会的意识和通过培训提高居民的参与能力。     

Assessing estuarine environmental quality using fish-based indices: performance evaluation under climatic instability

The seasonal variation of five selected multimetric indices for the determination of the Ecological Quality Status (EQS) of transitional waters was evaluated, as well as the indices’ responses to an extreme drought event that occurred in 2005. The database used regards the Mondego River estuary, which was sampled from June 2003 to August 2006 on a monthly basis. Among the selected indices (EBI - Deegan et al. [Deegan, L., Finn, J.T., Ayvazlan, S.G., Ryder-Kieffer, C.A., Buonaccoesi, J., 1997. Development and validation of an Estuarine Biotic Integrity Index. Estuaries 30(3), 601-617], EDI - Borja et al. [Borja, A., Franco, J., Valencia, V., Bald, J., Muxika, I., Belzunce, M.J., Solaun, O., 2004. Implementation of the European Water Framework Directive from the Basque Country (northern Spain): a methodological approach. Marine Pollution Bulletin 48(3-4), 209-218], EFCI - Harrison and Whitfield [Harrison, T.D., Whitfield, A.K., 2004. A multi-metric fish index to assess the environmental condition of estuaries. Journal of Fish Biology 65, 683-710], EBI - Breine et al. [Breine, J.J., Maes, J., Quataert, P., Van den Bergh, E., Simoens, I., Van Thuyne, G., Belpaire, C., 2007. A fish-based assessment tool for the ecological quality of the brackish Scheldt estuary in Flanders (Belgium). Hydrobiologia 575, 141-159] and TFCI - Coates et al. [Coates, S., Waugh, A., Anwar, A., Robson, M., 2007. Efficacy of a multi-metric fish index as an analysis tool for the transitional fish component of the Water Framework Directive. Marine Pollution Bulletin 55, 225-240]), the EBI by Breine et al. (2007) was the only that evidenced clear interannual and seasonal variations. The EQS by the several indices ranged from “Low” to “High”, depending on the index considered, evidencing the high level of mismatch between indices. The results are discussed in the scope of the EU Water Framework Directive, regarding monitoring strategies, application of indices and EQS assessment.     

PAHs contamination and bacterial communities in mangrove surface sediments of the Jiulong River Estuary, China

Sixteen sediment samples collected from eight transects in a mangrove swamp of the Jiulong River Estuary, Fujian, China were investigated for their content of polycyclic aromatic hydrocarbons (PAHs) and the biodegradation potential of the indigenous microorganisms. The bacterial community structures in the mangrove sediments and in enrichment cultures were also investigated. The results showed that the total PAHs concentration of mangrove sediments ranged from 280 to 1074 ng g(-1) dry weight, that the PAHs composition pattern in the mangrove sediments was dominated by high molecular weight PAH components (4-6 rings), and that Benzo[ghi]perylene and Indeno[1,2,3-cd]pyrene were the most dominant at different stations. Abundant PAH-degrading bacteria were found in all the stations, the values of phenanthrene-degrading bacteria ranged from 5.85 x 10(4) to 7.80 x 10(5) CFU g(-1) dry weight, fluoranthene-degrading bacteria ranged from 5.25 x 10(4) to 5.79 x 10(5) CFU g(-1) dry weight, pyrene-degrading bacteria ranged from 3.10 x 10(4) to 6.97 x 10(5) CFU g(-1) dry weight and the benzo(a)pyrene-degrading bacteria ranged from 5.25 x 10(4) to 7.26 x 10(5) CFU g(-1) dry weight. DGGE analysis of PCR-amplified 16S rDNA gene fragments confirmed that there was a remarkable shift in the composition of the bacterial community due to the addition of the different model PAH compound phenanthrene (three ring PAH), fluoranthene(four ring PAH), pyrene(four ring PAH) and benzo(a)pyrene(five ring PAH) during enrichment batch culture. Eleven strains were obtained with different morphology and different degradation ability. The presence of common bands for microbial species in the cultures and in the native mangrove sediment DNA indicated that these strains could be potential in situ PAH-degraders.     

Bacterial community in deep subseafloor sediments from the western Pacific “warm pool”

The bacterial community in deep subseafloor sediments at a depth of 230 cm from the western Pacific “warm pool” is studied by construction of 16S rDNA clone library and PCR-RFLP (Restriction Fragment Length Polymorphism) analysis. The results indicate that the bacterial community in these sediments is mainly composed of five groups: α-Proteobacteria, β-Proteobacteria, CFB group (Cytophaga / Flexibacteria / Bacteroides), Acidobacteria and gram positive bacteria, with a few genera detected in each group. The most abundant bacteria group is α-Proteobacteria, and the next is β-Proteobacteria. The dominant species in α-and β-Proteobacteria are Sphingomonas paucimobilis and Pseudomonas alcaligenes respectively. The CFB group is simply composed of members belonging to Flavobacterium. The gram positive bacteria are rich, and mainly consists of the genus Geobacillus. The analysis of bacterial community indicates that organic matter is still abundant in the subseafloor sediments at the depth of 230 cm in the western Pacific “warm pool”. These bacteria in this deep biosphere may play an important role in the nitrogen cycle of deep sea sediments at “warm pool”. Supported by the National Key Basic Research Support Foundation of China (Grant No. G2000078500) and China Ocean Mineral Resources R&D Association Project (Grant No. DY105-4-2-4)     

中国近海浮游介形类大尺度生态研究Ⅳ.浮游介形类的生态群落与群落特征

以中国近海的浮游介形类为研究对象,分析其群落结构,将之区分为近岸群落,陆架缘区群落、外海群落以及介于其间的不稳定的、有时是孤立的过渡群落,同时,还阐述各群落的主要特征及讨论各群落的特权种结构。此外,根据海上取样结果,本文仅讨论０～２００ｍ水域内的群落结构。     

Community Development Approaches to Heart Health Promotion: A Geographical Perspective

This paper reports results of a qualitative study of community development approaches to heart health promotion in Ontario. Cardiovascular disease (CVD) represents a substantial proportion of the burden of illness experienced by western industrialized countries. Biomedical research has implicated lifestyle choices and socioeconomic conditions as primary determinants of CVD. There has been a resultant shift from curative to preventive/health promoting strategies to reduce this burden of illness. The Canadian Heart Health Initiative-Ontario Project (CHHIOP), a two-stage (quantitative and qualitative) longitudinal study, was designed to address issues of heart health promotion through the investigation and strengthening of community-based heart health activities in both the formal and informal public health systems. The study reported on in this paper forms one part of the qualitative stage and focuses on how community relationships and community development approaches play out in local contexts to shape the reality of (heart) health promotion practice. Analysis of key informant interviews using Ethnograph illustrates the centrality of community context, the lack of a common understanding of key concepts (e.g., community development), and the emergence of a shift in health agencies' ways of doing business characterized by increased partnering and collaboration in the delivery of (heart) health promotion programs. Local perspectives and the dynamics of intra-community relations were allowed to emerge through the use of qualitative approaches implying a need for place-sensitive (heart) health promotion strategies.     

The Space Community Policing Makes and the Body That Makes It

This paper examines the ways that community policing organizes urban space in order to increase the police's ability to observe and to enforce. The logic of that organization, I argue, rests in the particular way that police are integrating civilians into police practice as part of community policing's police-community partnership, a partnership that is characterized by the concrete metaphor of a policing body. This paper presents the results of twenty months of field research with the Boston Police Department whose community policing program, Neighborhood Policing, is being hailed as a national model.