对测绘成果档案管理工作的思考

测绘成果档案是各级测绘部门在测绘工作中形成的具有保存价值的基础测绘成果,成果管理工作具有非常重要的意义。随着现代科学技术的发展,电子数据逐步被数字测绘成果所取代,因此对测绘成果档案的管理提出了新的要求。目前测绘成果档案管理存在诸多问题。本文在分析这些问题的基础上提出当前测绘成果档案工作管理对策。     

中国北方不同气候区晴天陆面过程区域特征差异

采用2008年7～9月份观测的中国干旱-半干旱区实验观测协同与集成研究资料,将我国北方干旱一半干旱区根据气候类型和地理位置划分为西北干旱区、黄土高原区和东北冷区三个区域,分析了干旱-半干旱区陆面热量平衡和辐射平衡日变化的区域差异.结果显示:不同气候区域的地表辐射和能量过程差异明显,而这种差异主要源于大气和土壤中可利用水...     

东南沿海地区降水与全球海温变化的关系

为了解近50年来东南沿海地区降水与海温变化的关系,对该地区降水与全球海表温度进行了奇异值分解（SVD）。结果表明：印度洋、南海及赤道东太平洋地区是对东南沿海地区降水有影响的关键区域。东南沿海地区秋冬季的降水总体上来说对前期海温变化的响应不敏感,而东南沿海地区夏季降水受前期海温的影响较为明显,尤其是上年夏季北印度洋、南海地区海温的变化对当年降水有明显影响。因此,在预测东南沿海地区夏季降水时应该重点考虑上年夏季北印度洋及南海地区海温的变化情况。     

基于GIS的小麦赤霉病气象等级预报系统的设计与实现

以江苏省为例,介绍了基于地理信息系统的小麦赤霉病气象等级预报系统的设计思路及核心技术。系统采用VB.Net 2005和ArcEngine做为开发平台,基于MSSQL SERVER 2005数据库查询,利用日平均相对湿度、日平均气温和日照时数3个气象要素,用两种算法来计算小麦赤霉病发生发展的气象等级,生成包含地理信息的文字产品和图形产品,实现了小麦赤霉病气象等级业务预报。系统具有功能强大,算法高效,操作简单等特点,解决了业务部门资料分析处理和赤霉病气象等级预报的相关问题,具有很好的业务应用和推广价值。     

长江三角洲近46 a气温和降水的变化趋势

利用长江三角洲地区84个气象站观测数据,分析了长江三角洲1961—2006年气温和降水的时空变化趋势。结果表明,46 a间长江三角洲地区年平均气温上升趋势显著,冬季平均气温的增温幅度最大,春、秋次之。增温显著区域与城市带分布区域吻合。极端最低气温有明显上升,而年极端低温事件日数的下降趋势显著。部分地区的极端最高气温呈上升趋势,在城市密集带尤为突出。年降水量没有明显的变化趋势,但降水的季节分配有所变化,冬、夏季降水量呈现显著上升趋势,秋季降水量明显下降,春季没有明显变化。     

SHRIMP zircon U–Pb and molybdenite Re–Os isotopic dating of the tungsten deposits in the Tianmenshan–Hongtaoling W–Sn orefield, southern Jiangxi Province, China, and geological implications

The southern Jiangxi Province is a major part of the Nanling W–Sn metallogenic province of southern China, where all W–Sn ore deposits are temporally and spatially related to Mesozoic granitic intrusions. The Tianmenshan–Hongtaoling orefield is a recently explored territory endowed by several styles of W–Sn mineralization. The orefield comprises three composite granitic plutons: Tianmenshan, Hongtaoling and Zhangtiantang associated with several tens of W–Sn-polymetallic ore deposits (Maoping, Baxiannao, Niuling, Zhangdou, Yaolanzhai and others) along their contacts. In this study, four new SHRIMP zircon U–Pb ages were determined for three composite granitic plutons, and 33 molybdenite samples from five W–Sn deposits were analysed by ICP-MS Re–Os isotopic method. SHRIMP zircon U–Pb ages for both medium to coarse-gained biotite granite and porphyritic biotite monzogranite from the Tianmenshan composite pluton are 157.2 ± 2.2 Ma and 151.8 ± 2.9 Ma, respectively. Molybdenite Re–Os isochron ages for the related Baxiannao fracture-controlled tungsten deposits are 157.9 ± 1.5 Ma. Maoping greisens-type tungsten deposits were emplaced at 155.3 ± 2.8 Ma and the Maoping wolframite–quartz veins at 150.2 ± 2.8 Ma, respectively. The SHRIMP U–Pb age of zircons from the Hongtaoling biotite granite is 151.4 ± 3.1 Ma whereas the molybdenite Re–Os isochron ages of the genetically related Niuling endocontact tungsten quartz veins and Zhangdou exocontact tungsten quartz veins are 154.9 ± 4.1 to 154.6 ± 9.7 Ma and 149.1 ± 7.1 Ma, respectively. The SHRIMP zircon U–Pb age of the Zhangtiantang fine-grained muscovite granite is 156.9 ± 1.7 Ma, whereas the molybdenite Re–Os isochron age for the related Yaolanzhai greisens-type tungsten deposit is 155.8 ± 2.8 Ma. These new age data, combined with those available from the literature, indicate that the ages of W–Sn ores and related granites are Late Jurassic with a peak at 150 to 160 Ma, which corresponds to the widespread Mesozoic metallogenic event in southern China. Molybdenites from this group of tungsten deposits have quite low Re contents (29.1 to 2608 ppb), suggesting continental crustal provenance of the ore metals.     

广东河台金矿糜棱岩化过程构造-流体成矿研究

为了探讨糜棱岩化过程中的成矿作用,文章对广东河台金矿进行了构造流体过程的数值模拟研究。根据力的分解、显微构造及运动学涡度分析以及与模拟结果的对比,提出108°方向的双向挤压作用可能是本区糜棱岩化带形成时的力学环境。数值模拟结果结合前人研究成果表明,体积应变增量异常带有利于糜棱岩化和流体的聚集以及糜棱岩化过程中成矿作用的...     

世界主要国家碳排放强度历史变化趋势及相关关系研究

减少人类活动的温室气体特别是CO2排放量是国际社会已普遍达成共识的应对气候变暖的根本性途径。研究各国经济活动的碳排放强度的变化历史,可以为预测各国未来的碳排放强度趋势、制定未来的碳排放强度降低目标提供科学依据。利用美国橡树岭国家实验室CO2信息分析中心（CDIAC）的CO2排放数据、《世界人口、国内生产总值和人均国内生...     

Investigation of mercury levels in soil around a municipal solid waste incinerator in Shenzhen,China

Within the management hierarchy of municipal solid waste (MSW), incineration with energy recovery is a desired and viable option often used in densely populated and economically developed cities. The gaseous and particulate mercury (Hg) emitted from MSW incinerators may accumulate in the soil entering via dry and wet deposition. To investigate the soil Hg level and estimate the effects of the local meteorological and topographical characteristics (e.g., winds and terrain) on the soil Hg distribution, two layers of soil samples around an MSW incinerator in Shenzhen, China were collected and analyzed. Results showed that the Hg levels ranged from 0.012 to 0.136 mg kg⁻¹ and from 0.013 to 0.100 mg kg⁻¹ in the surface and subsurface soils, respectively. Long-term exposure of the soil to atmospheric Hg from the MSW incinerator dominates the spatial pattern of soil Hg. The wind frequency directly affected Hg distribution but not decisively. Interestingly, the variations of Hg level with downwind distance away from the stack were highly consistent with the terrain profile (r ²: 0.412–0.748). The effects of winds and terrain on soil Hg distribution and their mechanisms are discussed and general Hg dispersion patterns for transport on terrain are further proposed.     

An overview on observational instruments and measuring methods for dewfall

This paper systematically summarizes previous measuring methods and observational instruments for the magnitude of dewfall on land surface, analyzes the characteristics of common observational instruments for land surface dewfall, and describes several basic dewfall measurement methods. Moreover, the basic principles of these methods and instruments are interpreted, and their advantages, disadvantages, and applicability are analyzed. Recommendations for the further improvement of these observational instruments and the development of dewfall measuring methods are presented, and new technologies and scientific proposals for exploiting dewfall are elucidated.