基于"3S"技术的重庆市北碚区地质灾害评估预测系统

地理信息系统(G IS),遥感(RS),全球定位系统(GPS)技术在自身进一步发展的同时,也日益向集成化,一体化方向发展。“3S”技术一体化为区域地质灾害监测和预防提供了新的技术手段。本文从“3S”技术的集成着手,结合区域地质灾害评估的特点和发展需要,提出基于“3S”技术建立区域地质灾害系统的框架,探讨以“3S”技术为开发平台的区域地质灾害灾情系统的基本原理和方法。     

兰州新区浅层地温能赋存条件及土壤源热泵系统适宜性分析

浅层地温能的开发利用有助于优化区域能源结构、节约常规化石能源、减少CO₂排放。为掌握兰州新区浅层地温能的适宜性特点,对该类资源的开发规划和政府决策提供科学依据,以兰州新区建成区和规划区为研究对象,在分析区内浅层地温能赋存条件的基础上,依据掌握的多年实际勘查资料和测试数据,通过综合运用改进的层次分析法、综合指数法,对兰州新区440 km²的区域进行了土壤源热泵系统适宜性评价分析。结果表明：（1） 兰州新区拥有较为优异的浅层地温能赋存条件,区内地层结构简单且分布稳定,岩土体综合热导率、比热容、地温梯度均较高,十分有利于土壤源热泵系统的应用;而受到含水层富水性弱、水质差等因素的影响,地下水源热泵系统适宜性差。（2） 基于层次分析法建立的适宜性评价模型共划分3个属性准则和7个要素指标,采用指数标度分别构建了各层次的判断矩阵,并全部高精度通过一致性检验,同时优化了各要素参数的无量纲化方法,构建的评价模型更符合实际。（3） 研究区内对于土壤源热泵适宜性影响较大的要素主要是平均热导率和地温梯度。评价显示兰州新区土壤源热泵系统适宜、较适宜区总面积359.46 km²,占评价区总面积的81.70%,主要分布于秦王川盆地平原区,其余丘陵山区地带不适宜土壤源热泵系统的建设。评价结果对兰州新区乃至其他地质条件类似地区土壤源热泵系统的开发利用规划具有指导意义。     

干旱绿洲农业区土地利用转型生态环境效应及分异机制——基于三生空间主导功能判别视角

干旱绿洲农业区生态环境脆弱,开展土地利用转型生态环境效应研究能为该区国土空间优化和农业农村可持续发展提供参考依据。论文以张掖市甘州区为例,采用转移矩阵、生态环境质量指数、移动窗口法、生态贡献率及地理探测器模型,对干旱绿洲农业区土地利用转型生态环境效应及分异机制进行研究。结果表明：(1)1990—2020年生产和生活空间持续扩张、生态空间总体减少,结构从“单一农业空间增加”向“转换类型多元化”转变,功能由“生态转生产为主”向“生产与生活、生态与生产多功能相互转换”演变。(2) 1990—2020年土地利用转型生态环境效应总体为正,耕地面积占比较大的村镇质量指数相对较高;其他生态空间向林草水生态、农业生产空间转型的生态正效应最大,林草水生态空间向其他生态、农业生产空间转型的生态负效应最大,2010—2020年农业生产空间过度扩张挤压林草水生态空间引起的生态环境负效应正在显现。(3)人口密度、地均GDP和植被覆盖度是生态环境质量分异的关键因子,降水量、土地开发强度、耕地面积占比和地均水资源量是核心因子;因子交互作用使农业生产空间增加和林草水生态空间压缩权衡博弈产生自适应稳态机制,从而形成了总...     

基于最小二乘支持向量机的雷暴预报初探

利用2007年和2008年南京地区NCEP 1°×1°历史再分析资料和江苏省闪电定位资料,探讨最小二乘支持向量机(LS-SVM)方法在雷暴预报中的应用.将NCEP 1°×1°资料作为实况,选取了该资料与雷暴相关性较好的参数作为预报因子,而江苏省闪电定位资料则作为预报量,建立南京地区雷暴预报的最小二乘支持向量机模型,并用...     

基于应急疏散智能体模型模拟的城市避难所空间配置——以上海市静安区为例

城市应急避难所的空间配置一直是灾害防治和城市安全研究领域的热点问题。本文以城市居民尽快地,尽少拥挤地到达满足容纳需求的应急避难所为目标,整合遥感影像数据、高精度人口分布数据、交通路网数据和专家知识等数据,综合运用智能体模型和多准则决策方法,对城市避难所空间配置开展研究。本文设计了三类与应急疏散相关的智能体：政府智能体、避难所智能体和居民智能体,来实现应急疏散的模拟,并根据模拟结果支持应急避难所的空间选址和配置。选址方法上运用了多准则决策方法和权重敏感性分析,在选址高适宜区域内选定避难所的新建方案。以新的避难所空间布局和配置为条件,执行新一轮的应急疏散模拟过程,实现选址的循环优化,从而获得最终的避难所空间配置方案。本文以上海市静安区的应急避难所空间配置分析为案例,生成了该区域应急避难所的详细空间配置方案,该方案能帮助居民在尽少拥挤风险下尽快疏散到附近的避难所。本文提出的方法充实了中国城市避难所选址的相关理论与可操作性的技术基础,为其他地区开展避难所的配置工作提供借鉴与参考。     

原位地应力测量与实时监测在地震预报研究中的作用和意义

当2013年4月20日四川芦山Ms 7.0级大地震发生时,中国科学家已不再像2008年汶川Ms 8.0大地震发生时那样茫然和不知所措。其根本原因在于,2008年汶川大地震发生后,龙门山地区开展了大量的科学研究工作,已超前初步认知龙门山断裂带西南端具有潜在地震危险性,特别是原位地应力测量和实时监测已发现绝对地应力大小高值异常和相对地应力大小临震异常变化。论文简要介绍了地震预报国际主流观点与认识,梳理了地应力在地震预报研究中的作用和认识,探讨了2004 Parkfield earthquake钻孔应变监测结果给予的启示,详细介绍了原位地应力测量与实时监测在地震预报研究中应用的实践与探索。实践证明:地震预报是值得探索和研究的,原位地应力测量与实时监测是地震预报的有效方法之一。      

The stratigraphy and composition of the Latterbarrow and Redmain sandstones,Lake District,England

The Latterbarrow Formation, 400 m thick, has been mapped and subdivided informally into three members. These consist of quartz wacke sandstone and, in the upper member only, intercalated mudstones. The formation unconformably overlies the fossiliferous Skiddaw Group of late Tremadoc to middle Arenig age and is overlain disconformably by volcanic rocks that have been attributed to the Borrowdale Volcanic Group. Chemically, the sandstones are characterized by very low concentrations of CaO, Na₂O, and K₂O and unusually high total iron. MnO and MgO, such that iron, as Fe₂O₃, exceeds Al₂O₃. Mudstone in the upper member is illite rich, has a high K₂O content and is compositionally similar to K-bentonites derived from volcanic ash. Sedimentary structures and petrography suggest that the sediments were deposited in a sandy estuary and were derived from a similar source area to that of the Skiddaw Group. Throughout the succession there is evidence of distal volcanism, probably representing the earliest eruptions of the Borrowdale volcanic episode. The Redmain Formation, 100 m thick, is unconformably overlain by Carboniferous rocks but its relationship to the underlying Skiddaw Group is unknown. Though this lithic arenite shows some petrographic and geochemical similarities with the Latterbarrow sandstone, differences are such that it is possible they are not equivalent in age. The Redmain sandstone may be derived from the erosion of Skiddaw Group rocks.     

Township ecosystem health assessment based on fuzzy synthesis evaluation method: a case study of Tongzhou District, Beijing, China

With the quick development of urbanization, the urban environmental problem has broken out in rural towns. In this study, a reasonable review of the research progress in the field of urban ecosystem health was addressed. Based on the analysis of the structure-function characteristics of the compound ecosystem, the connotation of the township ecosystem health was determined. Then ecosystem health of eleven towns of Tongzhou District was evaluated. This was accomplished by first constructing an index system including three layers which were criterion, factor and index. The criterion layer contained five elements including vigor, organization structure, resilience, ecosystem service function and population health. The indicators amounted in the aggregate to twenty-two. Then the health assessment of the study area was carried out using the fuzzy synthesis evaluation method. The evaluation results were analyzed by GIS techniques. Comprehensive analysis for integral health has shown that eight towns are in sub-healthy conditions, and the other three towns of Songzhuang, Xiji and Yongledian are healthy.     

Potential of weight of evidence modelling for gully erosion hazard assessment in Mbire District – Zimbabwe

Gully erosion is an environmental concern particularly in areas where landcover has been modified by human activities. This study assessed the extent to which the potential of gully erosion could be successfully modelled as a function of seven environmental factors (landcover, soil type, distance from river, distance from road, Sediment Transport Index (STI), Stream Power Index (SPI) and Wetness Index (WI)) using a GIS-based Weight of Evidence Modelling (WEM) in the Mbire District of Zimbabwe. Results show that out of the studied seven factors affecting gully erosion, five were significantly correlated (p < 0.05) to gully occurrence, namely; landcover, soil type, distance from river, STI and SPI. Two factors; WI and distance from road were not significantly correlated to gully occurrence (p > 0.05). A gully erosion hazard map showed that 78% of the very high hazard class area is within a distance of 250 m from rivers. Model validation indicated that 70% of the validation set of gullies were in the high hazard and very high hazard class. The resulting map of areas susceptible to gully erosion has a prediction accuracy of 67.8%. The predictive capability of the weight of evidence model in this study suggests that landcover, soil type, distance from river, STI and SPI are useful in creating a gully erosion hazard map but may not be sufficient to produce a valid map of gully erosion hazard.     

曹妃甸滨海湿地生态系统支持服务价值空间分异研究

基于条件价值法和随机效应logit模型对曹妃甸湿地生态系统支持服务价值进行了评估,并应用距离衰减模型对支持服务价值的空间演化和区域差异进行了研究.结果 表明,在曹妃甸滨海湿地生态系统支持服务的构成要素中,湿地植被恢复对支持服务保护行为选择的影响效应最高,其次为湿地面积恢复影响效应,而生物多样性保护的影响效应最低;根据随...