通勤时间、社区活动对社区社会资本的影响：基于北京26个社区的调查研究

城市扩张和郊区化显著增加居民的通勤时间,减少居民在社区内及周边开展的日常活动,进而可能对居民的社区社会资本产生消极影响。基于2017年北京市26个社区居民的社区融合与活动日志问卷调查数据,通过构建结构方程模型,探讨通勤时间、社区活动对社区社会资本的影响机制。结果发现,控制居民社会经济属性和社区区位后,长时间通勤会减少居民在社区及周边1 000 m范围内开展的活动,并进一步对社区社交网络结构、社会信任和共同价值等社区社会资本的不同维度产生负面影响。此外,社区活动中社交娱乐活动的中介效应显著,而个人和家庭事务活动中介效应不显著。最后,证实了促进职住平衡、减少职住分离的规划政策对于增加居民社区活动及培育社区社会资本的重要意义。     

物质地理学的研究进展和启示：追踪物质(following the things)视角

伴随着“文化转向”与“再物质化”思潮的出现,物质地理学已经成为西方社会文化地理研究中新兴且活跃的研究分支之一,而追踪物质(following the things)是物质地理学中重要的方法论视角,它强调人文地理学所重视的“流动性”,通过追踪特定物质在流动过程中物质性的变化以及能动性,揭示物质流动中的社会关系与文化意义。论文通过梳理和分析西方学界中物质地理学的相关文献,阐述了近年来的研究进展,同时指出现阶段在追踪物质视角下该领域的主要议题为：物质的象征研究、物质与认同研究、生产与消费研究以及权力博弈与协商研究等内容。最后,论文归纳总结了当下物质地理学存在的研究局限与空白,展望了未来中国物质地理学研究可进一步探索的话题与方向,以期打开未来中国与西方国家物质地理学的对话窗口。     

Microbiota and Shelf Life of Whole and Gutted Pacific Saury(Cololabis saira) During Refrigerated Storage

Pacific saury(Cololabis saira)is usually sold as whole fish in wholesale markets,or in its gutted form which is easy for consumers to cook in retail markets.In order to assess the effect of gutting on the shelf life of Pacific saury during refrigerated storage and reveal the microbial community,fish samples grouped into(I)whole fish and(II)gutted fish were analyzed periodically for sensory,biochemical and microbiological characteristics,and high-throughput sequencing technology was used to investigate the microbiota.Results showed that the sensory score for the gutted fish became unacceptable on day 8,while the whole fish score remained acceptable for 10 days.The total volatile basic nitrogen(TVB-N)value of the gutted fish reached 30 mg N(100 g)^-1 on day 6,while that of the whole samples surpassed 30 mg N(100 g)^-1 on day 10.The thiobarbituric acid reactive substances(TBARS)value of the gutted fish got close to 5.0 mg kg^-1 on day 10,while that of the whole samples surpassed 5.0 mg kg^-1 on day 14.The aerobic plate colony counts(APCs)for the gutted and whole Pacific saury reached 7.0 log10 CFUg^-1 on days 6 and 10,respectively.Organoleptic,biochemical and microbiological analyses revealed that shelf-lives should be 6–8 days for gutted fish and 10 days for whole fish.Microbiota analysis results showed that gutting partly changed the initial microbiota,but didn't alter the dominant bacteria during storage.When the fish were spoiled,high proportion of Pseudomonadaceae was detected in both groups.     

关于发展人工影响天气数值模式的一些问题

人工影响天气的学科基础是中小尺度天气动力学与云降水物理学,需要将天气-动力-云降水物理耦合为一体。考虑到目前将天气动力学性质的基础数值模式用于人工影响天气中的问题,从数值模式动力方程、模式分辨率、云物理过程、数值求解方案、初边值条件等方面系统地探索了发展人工影响天气数值模式中一些需要重点解决、且不可忽视的特色问题,并举例对相关问题提出了解决思路和方法。期望提出的问题有助于构思更适合于人工影响天气数值模式,使数值模式功能真正向满足人工影响天气的要求靠近一步。     

Rural Social Networks along Amazonian Rivers: Seeds,Labor and Soccer among Communities on the Napo River,Peru

Research on Amazonian communities has focussed more often on rural‐urban linkages than on links among rural communities. This is unsurprising, given the low density of population, limited intercommunity commerce, and importance of direct city‐market relations. Social relations among rural communities are also important in shaping rural livelihoods and lifeways. We report on the findings of a large‐scale census of communities in the Napo River basin in northeastern Peru (n=174). Data were gathered on intervillage crop seed acquisition and cooperative labor sharing as two key inputs in agriculture, and on intervillage soccer matches, which are integral to rural social life. We analyze the socio‐spatial networks of each practice, paying attention to settlement patterns, community ethnicity, and differential access to the uplands. We find that seeds and labor flow along soccer network lines. Rural social networks appear to be structured strongly by ethnicity (homophily) and reflect important complementarities between upland and lowland communities (weak ties).     

面向土地全生命周期的地籍时空管理系统设计与探讨

从地籍动态管理的角度,提出了土地与宗地全生命周期的概念。基于此,设计了地籍时空数据结构,探讨了面向全生命周期的地籍时空管理系统的结构和功能,并将研发的系统运用在实际业务中,以贯穿于其全生命周期管理。     

渤海湾西北岸泻湖自然演变及其人为陆化

渤海湾西北岸发育有中纬度地区典型的滨外沙坝泻湖及沿岸沙坝泻湖。泻湖不仅是该海岸区域内的一个重要组成部分,同时亦是海岸带自然资源丰富的地带。然而,由于泻湖的自然演变退化,更重要的是人类活动的影响,致使泻湖生境遭到严重破坏,同时也加速了泻湖陆化消亡过程。本文以渤海湾西北岸泻湖为例,讨论了泻湖的自然演变及其人为陆化问题。     

30多年来呼伦贝尔草原沙漠化的演变特点及防治对策研究

采用遥感技术与野外调查相结合的方法,通过3个典型小区对呼伦贝尔草原30多年来的沙漠化演变特点进行了系统研究。结果表明:该区的樟子松林区发生着强烈的沙漠化逆转,许多地段已转变为非沙漠化土地;其它地区除部分地段由于人类的积极治理而发生沙漠化逆转外,仍处于不断发展的过程中。因此,对于樟子松天然分布区,可充分利用樟子松的优良防风固沙特性和较强的扩展能力来防治沙漠化,而对其它地区则应以封育为主,加强人工抚育和草原建设。     

Ecological and Life History Characteristics of Botryllus schlosseri Tunicata Populations Inhabiting Undersurface Shallow-Water Stones

Abstract. Populations of Botryllus schlosseri PALLAS 1772. a cosmopolitan colonial ascidian. were examined on the undersurface of stones for the first time in three adjoining localities along the Israeli Mediterranean coast. A two-year study of 1589 stones which were inhabited by 1345 colonies, revealed that colony coverage was < 1.5 % of the total available substrate area; values were highest in spring, lowest in winter. The two years differed significantly in the number of colonies · m ², and these numbers were correlated with mean seawater temperatures. Most of the stones contained 1–5 Botryllus colonies year-round; no significant correlation was found between number and stone size. The brown morph was dominant 80 % at all three localities. The distribution of other colour morphs differed between localities. Reproductive colonies were either hermaphroditic or contained male gonads only. Peak reproduction was in the spring, but did not correlate with seawater temperatures. While colony size ranged between I and 1I55zooids, sexually mature colonies consisted of 171–273 zooids on the average, compared with 37–90 zooids for sterile colonies. The three populations differed significantly in several ecological and life history characteristics. This further confirmed past studies indicating that Botryllus populations are characteristically divided into local subpopulations exhibiting microgeographic differences in life history patterns. The results are compared with the accumulated data on other world-wide Botryllus populations residing in other habitats.     

厦门港帽铃水母生活史的研究

本文详细描述了厦门港帽铃水母从胚囊期到水螅体的各发育期的外部形态、发育时间与大小,以及附着与变态过程,并对其结果进行讨论。