孤岛工作面长度对下伏大巷稳定性影响研究

以开滦矿区某矿8#孤岛煤柱回采为工程背景,针对孤岛工作面长度对底板垂直应力的分布影响及下伏大巷围岩稳定性问题展开研究。采用理论分析和数值模拟相结合的手段,建立了孤岛工作面在倾向方向上的底板受力模型,采用半无限体空间理论,推导出底板垂直应力计算公式,将该孤岛工作面实际地质参数带入公式,得出了孤岛工作面长度与底板应力之间的函数曲线。研究表明:当该孤岛工作面长60 m时,对下方-480 m水平大巷产生的垂直应力最小。通过FLAC 3D数值模拟方法验证了8#孤岛工作面合理尺寸（60 m)比实际孤岛工作面长度（100 m)对下方水平大巷的采动影响小,便于维护。     

陕西关中城市群热岛效应指标初探

选取陕西关中地区12个大、小城市,1970—2009年逐月平均最高、最低和平均气温资料进行不同季节的城市热岛效应分析,对描述热岛效应的热岛强度指标进行研究,并提出以华县站为对比站的改进型温度差直线趋势作为关中城市群热岛强度衡量指标。该指标既消除了局地气候变化影响又剔除了个别小城市增温速率过快的影响。计算结果发现：无论城市规模大小,关中城市群一年四季都存在热岛效应。热岛强度冬春季强,夏秋季弱。大城市的热岛强度无论季节或年增加幅度均比小城市大。     

Biogeographical differences between the two Capra pyrenaica subspecies, C. p. victoriae and C. p. hispanica, inhabiting the Iberian Peninsula: Implications for conservation

The Iberian wild goat (Capra pyrenaica), an endemic species to the Iberian Peninsula, was represented in the past by four subspecies. Currently, the conservation status of the recognized subspecies - C. p. hispanica and C. p. victoriae - is quite different, being the former broadly distributed while the latter inhabits fewer and smaller areas. In this global context, our specific aims were to assess the biogeographical relationships, similarities and differences between the Iberian wild goat subspecies, and to evaluate their conservation status from a biogeographical perspective. We modelled the ecogeographical favourability for each subspecies, and also for the whole species, and we comparatively analyzed the spatial relationships among models in order to detect differential biogeographical patterns. Our results showed a differential pattern for each Iberian wild goat subspecies, and thus each one should be independently considered when designing management strategies. The distribution of C. p. victoriae was closely related to climatic conditions, thus it is highly sensitive to variations in climatic characteristics. Finally, from the perspective of metapopulation theory, and according to the geographical structure of their favourable areas, C. p. victoriae is at higher risk than C. p. hispanica. We discuss the implications of our results for species/subspecies conservation, and highlight the importance of conservation biogeography.     

城镇地区生态安全评价及对策——以上海崇明岛为例

从区域生态安全内涵出发,基于可持续发展理论、自然—经济—社会复合生态系统理论和压力(pressure)—状态(state)—响应(response)概念模型,从资源环境负荷、生态环境状态、人类社会响应3方面构建城镇生态安全评价指标体系。选择上海崇明岛处于核心地位且代表着不同城镇化水平(较高、中等、较低)的城桥镇、堡镇、陈家镇为研究对象,通过实地调研、监测、实验分析等方式获取指标数据,应用层次分析法(AHP)确定指标权重,并通过综合指数模型进行安全评价。评价结果表明:3个城镇生态安全综合评价结果为城桥镇(0.773 3)>陈家镇(0.762 8)>堡镇(0.749 0),社会经济的发展对资源环境的负荷较小,生态环境现状水平良好,但人类响应措施滞后;随着城镇化进程的加快,部分生态环境要素可能有恶化趋势,现已进入预警状态。     

Land system architecture for urban sustainability: new directions for land system science illustrated by application to the urban heat island problem

ABSTRACT

Land system science (LSS) has expanded its research focus from the drivers of land-use and -cover change primarily in rural wildlands to include the social-environmental consequences of this change, urban areas, and sustainability practice. Land system architecture, interacting with the landscape mosaic approach in ecology, offers a special niche for the entry of rural areas and wildlands into urban sustainability research through examinations of the composition and configuration of ‘cityscapes’. Given the fine-grain data requirements of heterogeneous cityscapes, emergent land architecture-mosaic approaches have largely explored the urban heat island (UHI) problem, a topic that links LSS with the interests of urban climatology, engineering, and planning in city morphology or geometry. The subtle distinctions in the treatment of land configuration between land architecture-mosaic approaches and urban morphology-geometry approaches are identified. Several examples of the land architecture-mosaic approach illustrate the understanding gained about the UHI problem as well as its complementarity with morphology-geometry approaches. This understanding provides insights about the design of urban areas at the parcel to neighborhood scales to ameliorate extreme temperatures, an issue of increasing concern for urban areas worldwide and consistent with the sustainability problems identified by such international programs as Future Earth.     

Assumption‐versus data‐based approaches to summarizing species’ ranges

For conservation decision making, species’ geographic distributions are mapped using various approaches. Some such efforts have downscaled versions of coarse‐resolution extent‐of‐occurrence maps to fine resolutions for conservation planning. We examined the quality of the extent‐of‐occurrence maps as range summaries and the utility of refining those maps into fine‐resolution distributional hypotheses. Extent‐of‐occurrence maps tend to be overly simple, omit many known and well‐documented populations, and likely frequently include many areas not holding populations. Refinement steps involve typological assumptions about habitat preferences and elevational ranges of species, which can introduce substantial error in estimates of species’ true areas of distribution. However, no model‐evaluation steps are taken to assess the predictive ability of these models, so model inaccuracies are not noticed. Whereas range summaries derived by these methods may be useful in coarse‐grained, global‐extent studies, their continued use in on‐the‐ground conservation applications at fine spatial resolutions is not advisable in light of reliance on assumptions, lack of real spatial resolution, and lack of testing. In contrast, data‐driven techniques that integrate primary data on biodiversity occurrence with remotely sensed data that summarize environmental dimensions (i.e., ecological niche modeling or species distribution modeling) offer data‐driven solutions based on a minimum of assumptions that can be evaluated and validated quantitatively to offer a well‐founded, widely accepted method for summarizing species’ distributional patterns for conservation applications.     

文化型海岛善行旅游发展的战略路径选择——以福建湄洲岛为例

海岛旅游发展再一次成为海洋旅游业发展的新突破口.以湄洲岛为代表的文化型海岛凭借其深厚的文化内涵和优质的海滨旅游资源成为海洋旅游业发展的生力军.从解读文化型海岛内涵及特征入手,全面剖析了湄洲岛的优势条件,从文化价值、文化需求、文化生态、文化形态等方面深入挖掘湄洲岛所含文化特性,以此构建起湄洲岛善行旅游发展的“四和四共一发展”的互动效应,探寻出一条具有文化型海岛特点的湄洲岛善行旅游发展之路.     

生态浮岛技术用于河湖污染修复进展研究

中国江河湖库水体污染状况严重,且难以用传统的物理、化学方法进行修复,生态浮岛作为一种生物－生态修复技术以其操作简单、处理效果好以及环境风险低等优点在河湖污染修复中得到大家的广泛关注。以发展进程为线索,作用主体和动力模式为依据对生态浮岛技术进行归纳总结,分类阐述了传统生态浮岛、组合型浮岛和微动力浮岛的研究及应用情况。展望了今后的研究方向,包括创建适于硝化菌和反硝化菌生长的微环境,加强生态系统交互作用和引入太阳能装置等。以期对生态浮岛在河湖污染修复中的研究及应用提供参考。     

中国地表城市热岛驱动因素及其空间异质性

基于MODIS卫星遥感数据,计算了中国284个地级市2018年的年平均地表城市热岛强度,分析了中国地表城市热岛的空间分布规律和空间集聚模式.结合多元遥感数据、气象数据和社会经济统计数据,利用地理加权回归模型分析了日间和夜间地表城市热岛强度主要驱动因素的空间异质性结果表明,中国地表城市热岛强度的空间分布存在明显的空间自相...     

生物浮岛对三峡库区典型支流库湾水质和浮游藻类的影响

在三峡库区香溪河的支流高岚河库湾修建生物浮岛,研究生物浮岛对三峡库区典型支流库湾水质和浮游藻类的影响.结果表明,高岚河水质处于中营养型-轻度富营养型水平.8月藻类大量生长期间,浮岛区水体Chl-a、DO和CODMn含量低于对照区,NH4+-N含量高于对照区.浮岛植物对TN负荷的去除效果由高到低依次为美人蕉(Canna indica)、风车草(Cyperus alternifolius)、菖蒲(Pontederia cordata)和梭鱼草(Acorus calamus),对TP负荷的去除效果由高到低依次为美人蕉、风车草、梭鱼草和菖蒲.在浮岛区和对照区共发现藻类7门31属,4月以绿藻和硅藻为主,8月以蓝藻为主.浮岛区和对照区藻类种群结构无明显差异,但4和8月浮岛区藻类生物量明显低于对照区.