贵州绥阳双河洞国家地质公园洞穴基本特征及成因探讨   总被引：7，自引：0，他引：7  

刘平 《贵州地质》2008,25(4)

106地质大队于1959～1960年曾对双河洞石膏矿进行过地质勘查。1986年～2006年4月,先后有中、法、日等国专家19次进双河洞考察,初步查明了该洞总长度为105.7km,是亚洲第二长洞,在世界上排名第16位。该洞不仅规模宏大,网络复杂,且有一定数量的次生淋滤型石膏矿分布,成为国内外罕见的独特洞穴景观。双河洞自2004年荣获国家地质公园称号以来,已引起国内外专家的广泛关注。该洞的形成,与该区域大范围内下寒武统清虚洞组上部至中寒武统平井组下部白云岩中,含大量硬石膏层有着密切的成因联系。  相似文献   

Microhabitat preferences and depth distribution of combtooth blennies (Blenniidae) in the Gulf of Trieste (North Adriatic Sea)     

Martina Orlando-Bonaca  & Lovrenc Lipej 《Marine Ecology》2007,28(3):418-428

The microhabitat preferences and depth distribution of blenniid species (Blenniidae) in the Gulf of Trieste (North Adriatic Sea) were surveyed using the all‐occurrence sampling method, a non‐destructive visual census method, aided by SCUBA diving. Fourteen species were identified during the entire survey. Four species showed to be indiscriminate in their microhabitat choice while 10 species were classified as infrequent in the surveyed coastal area. A statistically significant correlation was found between the blenniid assemblage and nine microhabitat variables. The blenniid assemblage was divided in two main groups, by the use of canonical correspondence analysis, electivity index, and the depth distribution analysis. The first group comprises species that dwell in surface waters and show a high positive correlation with boulders, the presence of Mytilus galloprovincialis, cirripeds and empty holes bored by Lithophaga lithophaga. The second group includes species that mostly inhabit deeper waters and show a high positive correlation with rocks covered by precoralligenous bioformations.  相似文献   

山东省海岸工程可持续发展的若干问题     

关德斌  宫崇楠 《海岸工程》2001,20(2):1-7

从风暴潮、黄河口治理、海水地下入侵与咸水侵染、海岸及沿海污染、沿海滩涂与黄河三角洲开发、海上交通和港口发展、海岸和海上石油开采、海岸工业基地建设、沿海旅游和海岛开发 ,以及沿岸淡水资源开发与海水利用等 1 0个方面 ,对山东省海岸工程的可持续发展问题进行了分析和讨论 ,并针对具体问题 ,提出了解决可持续发展问题的对策与措施。  相似文献   

基于空间信息技术的堰塞湖库容分析方法研究     

陈晓玲  陆建忠  蔡晓斌  李辉  殷守敬 《遥感学报》2008,12(6)

快速准确计算堰塞湖库容,对了解地震堰塞湖险情具有重要的意义.利用遥感和地理信息系统等空间信息技术,提出了一种基于像素的三维水面的计算动库容的方法,能准确计算水面为曲面,包括动库容在内的总库容.该方法利用遥感影像提取水体边界线,与DEM求交后可得到带高程的边界点,利用空间插值技术获得三维水面,然后利用库容计算模型求解.同时,在分析该算法计算效率的基础上,提出了基于河流分段的库容计算优化算法,最后通过实验对比分析了该方法的合理性和优越性.  相似文献   

The Creation of a National Agricultural Land Use Dataset: Combining Pycnophylactic Interpolation with Dasymetric Mapping Techniques     

Alexis Comber  Chris Proctor  Steve Anthony 《Transactions in GIS》2008,12(6):775-791

Agricultural Census data is summarised over spatially coarse reporting units for reasons of farm confidentiality. This is problematic for research at a local level. This article describes an approach combining dasymetric and volume preserving techniques to create a national land use dataset at 1 km² resolution. The results for an English county are compared with contemporaneous aggregated habitat data. The results show that the accurate estimates of local agricultural land use (Arable and Grass) patterns can be estimated when individual 1 km squares are combined into blocks of > 9 squares, thereby providing local estimates of agricultural land use. This in turn allows more detailed modelling of land uses related to specific livestock and cropping activities. The dataset created by this work has been subject to extensive external validation through its incorporation into a number of other national models: nitrate leaching (e.g. MAGPIE, NEAP‐N), waste, and pathogen modelling related to agricultural activity.  相似文献   

加强地理信息资源建设和开发利用的思考   总被引：1，自引：0，他引：1  

王晓国  刘亚东  王开宇 《测绘与空间地理信息》2008,31(3)

地理信息资源的建设和开发利用在准确掌握国情国力、提高管理决策水平、管理社会公共事务、处理经济社会发展等重大问题中将发挥越来越重要的作用。本文在对发改委、测绘、国土、环境保护等部门进行调研的基础上,从我国地理信息的获取和利用现状、地理信息资源建设和开发利用政策法规的制定、产业发展以及国家安全等四个方面进行了研究,并提出了建议。  相似文献   

Oil and gas resource assessment: The linkage between geological analysis and discovery process model results     

Lawrence J. Drew  John H. Schuenemeyer 《Natural Resources Research》1996,5(1):33-42

Two widely-used techniques to estimate the volume of remaining oil and gas resources are discovery process modeling and geologic assessment. Both were used in a recent national assessment of oil and gas resources of the United States. Parallel estimates were obtained for 27 provinces. Geological-based estimates can typically see into areas not available to discovery process models (that is areas with little or no exploration history) and thus, on average, yield higher estimates. However, a linear relation does exist between the mean estimates obtained from these two methods. In addition, other variables were found in a multiple regression model that explained much of the difference. Thus, it is possible to perform discovery process modeling and adjust the estimates to yield results that might be expected from geological-based assessments.  相似文献   

Commentary and critique of “accounting for mineral resources: Issues and BEA's initial estimates”     

DeVerle Harris  Michael Rieber 《Natural Resources Research》1996,5(1):7-21

The Bureau of Economic Analysis (BEA), U.S. Department of Commerce, in keeping with broad international efforts to green national gross domestic product (GDP) accounts, has attempted to create satellite accounts for mineral depletion. The present paper criticizes the BEA's unit rent measure of resource depletion, which is based upon Hotelling's pure theory of exhaustion. Following a thorough criticism of Hotelling's theory as a real-world model of mineral prices, practical issues related to the treatment of recycling, exploration, definition of reserves/resources, and their valuation/exploitation are introduced. For crude oil and natural gas and the nonfuel minerals, specific application problems of joint products and residuals complicate BEA's assumptions and efforts.  相似文献   

基于消息通知机制的国省数据共享系统的设计与实现     

顾文静  戴晴  张媛媛  王鹏 《气象科技》2021,49(6):860-868

为解决卫星广播传输缺陷及省级用户获取临省实时观测资料和实况分析产品等迫切的业务需求，设计并实现了基于消息通知机制的国省数据共享系统。系统基于RabbitMQ的消息机制进行业务和数据资源的整合及集成，采用多层体系架构，满足基于地面宽带的数据快速有序下载和卫星广播数据补调等国省数据共享需求，支持大容量多种数据的高速传输，支持HTTP、FTP、SFTP等多种数据传输协议。系统已经上线提供服务，实现智能网格、多源融合实况分析等25种气象资料的国省数据共享，月平均共享数据量达6.3 TB，且建立全流程监视，有效保障数据共享的时效性。  相似文献   

关于我国国家基础地理信息系统数据库按内容分级的探讨——以1∶5万数据库为例     

王中元  唐新明  翟亮  高小明 《测绘科学》2005,(6)

在诸多地理信息系统中,基础地理信息系统是各类地理信息系统用户的统一空间载体,面向全社会和各专业部门,因而国家基础地理信息系统数据库的产品需求既是最广泛的,也是最复杂的。本文针对社会上不同行业、部门对国家基础地理信息系统数据库产品的不同需求程度,以1∶5万数据库为例,采用调查、统计分析和空间分析的方法,把国家基础地理信息系统数据库按内容创造性地分为三个等级,并得出“国家基础地理信息1∶5万数据库内容等级划分方案”,为下一步三级数据库产品生产提供了参考。  相似文献