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61.
工程建设地质环境适宜性评价是国土空间规划编制的基础。以连云港城市规划区为例,探索地上地下工程建设适宜性一体化评价指标体系和方法。一体化评价是一个空间综合决策问题,涉及多个层次多种因素。借鉴经济领域的负面清单模式,基于自然因素的负面清单建立一体化评价指标体系。一体化评价地上和地下评价指标差异性较为明显,地上评价考虑地形坡度、地基承载力、桩基埋深等11因素,而地下空间评价则不考虑地形坡度、桩基埋深等因素。基于层次分析法与熵权系数法的综合评价方法来确定评价指标的权重,采用GIS平台采用多目标线性加权函数模型进行了工程建设一体化分区评价。评价结果显示:工程建设适宜性好区和较好区分布广泛,占比73.94%-93.22%。随着竖向深度增加,地下空间开发地质适宜性好的区域面积显著增加。地上空间适宜性主要受软土、腐蚀性土及地质灾害影响。浅层(0-15 m)地下空间开发地质适宜性主要受浅埋厚层软土的影响,地下空间开发面临软土变形的风险。次浅层(15-30 m)与次深层(30-50 m)地下空间开发地质适宜性主要受砂层涌水量和岩土结合面的影响。从评价结果看,地下空间工程建设适宜性优于地上,建议地下空间分为3个竖向分层进行开发,充分开发利用15 m以浅的地下空间,超前规划次浅层与次深层地下空间,工程建设应尽量避开适宜性一般区和差区。适宜性好区和较好区国土空间规划编制时应着重考虑。 相似文献
62.
Here we describe an isolated tooth of a metriorhynchid crocodylomorph from the Hybla Formation (Aptian, Lower Cretaceous) of Rocca Chi Parra quarry (Montagna Grande, Calatafimi, Trapani Province), Sicily, Italy. The specimen shares with the Upper Jurassic taxon Plesiosuchus manselii a mediolaterally compressed conical tooth crown, noticeable lingual curvature, mesial and distal carinae with microscopic, rectangular contiguous denticles, strong distal curvature of the mesial margin, and the presence of weak 'carinal flanges' on the labial and lingual surfaces (which are preeminent at the mid-crown). This suite of morphologies is also present in an unnamed Valanginian (Lower Cretaceous) plesiosuchinan from France. However, the Sicilian tooth differs from these taxa in having more pronounced carinae, and faint apicobasally aligned enamel ridges. It also differs from P. manselii in having more extensive 'carinal flanges' on the labial surface. The specimen extends the known geological range of Metriorhynchidae and Thalattosuchia by approximately 7–8 million years. This overturns previous hypotheses of Metriorhynchidae becoming extinct early in the Early Cretaceous. 相似文献
63.
《Marine Policy》2015
Shiffman et al. assert that International Game Fish Association (IGFA) records are threatening imperiled fish populations. Here I report that 88% of the species identified by the authors were first listed as threatened within the last 20 years and, during this time, IGFA received a total of 15 All-Tackle record applications for these species. The low number of records placed within the appropriate context of total global landings for these species does not support the hypothesis that IGFA All-Tackle records have a disproportionately negative impact on imperiled species as the authors suggest, but rather a disproportionately low impact. 相似文献
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Hua Qin Yanu Prasetyo Martha Bass Christine Sanders Elizabeth Prentice Quyen Nguyen 《社会与自然资源》2020,33(9):1131-1148
AbstractEnvironmental sociology and the sociology of natural resources have become two established research areas in the United States with distinct institutional origins, research themes, and theoretical roots, as well as associated professional networks, journals, and conferences. Existing discussions of the relationships between the two subdisciplines are largely based on personal reflections and exploratory analyses. However, there is still not a clear understanding of the overall picture of interdisciplinary sociological research on human–nature interactions. In this study we conduct a comprehensive bibliometric analysis of 8027 articles published in 30 selected academic journals during 1985–2017. Findings of this research provide a more complete view of the intellectual landscape of environmental and resource sociology. Overall, the study produces an empirically-based characterization of environmental sociology and the sociology of natural resources in terms of coauthorship and citation networks, and highlights the need for more sustained synthesis across different knowledge domains. 相似文献
68.
Military sonar has the potential to negatively impact marine mammals. To investigate factors affecting behavioral disruption in California sea lions (Zalophus californianus), fifteen sea lions participated in a controlled exposure study using a simulated tactical sonar signal (1 s duration, 3250–3450 Hz) as a stimulus. Subjects were placed into groups of three and each group received a stimulus exposure of 125, 140, 155, 170, or 185 dB re: 1 μPa (rms). Each subject was trained to swim across an enclosure, touch a paddle, and return to the start location. Sound exposures occurred at the mid-point of the enclosure. Control and exposure sessions were run consecutively and each consisted of ten, 30-s trials. The occurrence and severity of behavioral responses were used to create acoustic dose–response and dose–severity functions. Age of the subject significantly affected the dose–response relationship, but not the dose–severity relationship. Repetitive exposures did not affect the dose–response relationship. 相似文献
69.
地震是一种突发性强和破坏性大的自然灾害,重特大地震的发生往往致使较重的人员伤亡和财产损失。科学制作并合理利用应急技术产品是提升抢险救援效率的有效措施,可以有力支撑指挥层级快速决策与应急指挥。以四川长宁"6·17"地震中的应急技术保障工作为参鉴,结合当前常用应急监测技术手段,全面梳理应急技术保障产品在实践应用中的常态问题。并在此基础上,引入"清单制"管理思维,从何种阶段制作哪类产品,哪类产品需要哪些要素上进行细化构思,建立地震灾害应急技术保障产品清单,从管理模式上规范技术保障机制,促使地震应急技术支撑有力并且有序,切实提升震后应急处置效率。 相似文献
70.
This paper presents an approach to automated identification of slum area change patterns in Hyderabad, India, using multi-year and multi-sensor very high resolution satellite imagery. It relies upon a lacunarity-based slum detection algorithm, combined with Canny- and LSD-based imagery pre-processing routines. This method outputs plausible and spatially explicit slum locations for the whole urban agglomeration of Hyderabad in years 2003 and 2010. The results indicate a considerable growth of area occupied by slums between these years and allow identification of trends in slum development in this urban agglomeration. 相似文献