北京地区草坪昆虫群落的初步研究

对北京市不同类型的草坪昆虫群落进行了初步调查研究,共采集到昆虫17 765头,隶属于89个科,11个目.昆虫种类组成主要以膜翅目和双翅目为主,占群落总科数的59.55%,而从数量上则以双翅目和同翅目为最多,占样本总数60.81%,不同类型的草坪昆虫群落组成不同,其昆虫群落丰富度、多样性、优势类群随着季节而成动态变化.     

向家坝水电站工程施工区左岸植被分析及规划建议

本文利用GIS技术对向家坝水电站工程施工区左岸航拍片(50×50)进行判读,利用航拍植被斑块的空间关系弄清植被分布格局,通过对向家坝水电站工程施工区左岸的植被布局的研究,确定不同类别的植被功能核,对研究区域植被恢复现状进行分析,并提出优化规划建议.     

Finding of ancient materials in Cathaysia and implication for the formation of Precambrian crust

U-Pb dating for fifty-six detrltsl zircons from a paragneiss in Nanxiong area, northern Guangdong Province, Indicates that the latest Neoproterozoic sediments in Cathaysia hinterland are composed of numerous Grenvillian and Necerchaean clasUc materials, as well as some Mesoproterozolc detritus. Minor Paleoarchaean （3.76 Ga） and Mesoarchaean （3.0-3.2 Ga） zircons, which are the oldest zircons In South China, also are firstly found in the sediments, suggesting that the Cathaysia Block may contsln very old materials. The Hf isotope compositions of thirty-seven zircons reveal that these clastlc materials have different origins. Minor zircons crystslllzed from magma generated from relatively juvenile crust, while the parental magma of most zircons was derived from ancient crust. Integration of U-Pb dating and Hf Isotope analysis of these zircons suggests that the generation of juvenile crust in the Cathaysia block mainly occurred at 2.5-2.6 Ga. Mesoarchaean （3.0-3.3 Ga）, late Paleoproterozolc （-1.8 Ga） and Paleoarchaean （-3.7 Ga） may also be important episodes of crustal growth. Grenvllllan magmatism is extremely Intense, but it mainly involved recycling of ancient crustal components with little formation of Juvenile crust. The marked presence of -2.1 Ga Hf model ages and the absence of the zircons with crystsllizatlon ages at -2.1 Ga suggest that the parental magma of many zircons was probably derived from the mixed source consisting of Neoarchaean and late Paleoproterozoic materlals.     

武广铁路的修建对石门台保护区陆生脊椎动物的影响

正在修建的武广铁路客运专线由北向南纵贯广东石门台自然保护区．2006年7月,通过实地调查,结合以前的调查资料,探讨了铁路施工和今后运营过程中可能产生的噪音、粉尘、气流、生活垃圾等,对石门台保护区内铁路通过区域的18目46科111种陆生脊椎动物的生存所造成的影响,并进行了初步评价,提出了保护建议．     

河北省工业主导产业优化研究

以2016年中国统计年鉴和河北省经济年鉴为数据主要获取来源,根据国家目前政策和河北省工业的发展现状,建立了河北省工业的主导产业评价指标体系,采用因子分析法和主成分分析法对其分别进行了定性评价和定量评价,确定了工业中39个产业的综合得分和排名,提出了优化河北省主导产业发展的建议。     

北京白河湿地夏季昆虫群落组成特征的初步分析

本研究利用网捕法对北京市白河湿地昆虫群落进行了调查,共获标本21 429只,隶属于15目149科.其中,叶蝉科、爪姚科、盲蝽科、蚜科、潜蝇科、飞虱科、摇蚊科等19科为优势或常见科.在不同功能类群中,植食性昆虫最占优势,捕食性和寄生性昆虫个体较少,但类群较多.白河湿地昆虫群落的组成不仅较北京人工草坪群落和圆明园群落丰富,而且也较河南黄河、江西鄱阳湖以及厦门马銮湾3个湿地昆虫群落丰富,并以双翅目和膜翅目尤为突出.昆虫是湿地生态系统食物网的重要组成部分,研究湿地昆虫群落多样性对湿地生态系统功能的评价具有重要意义.白河湿地虽然面积较小,却蕴藏着丰富的昆虫多样性,应引起充分重视.     

软岩铁路隧道支护受力及优化分析

以玉磨铁路曼么二号隧道为背景,分析软岩隧道受力特征,以及施作临时仰拱对隧道围岩压力、位移的影响,为以后的工程方案比选提供参考。通过采用数值模拟和现场监测实际数据对比分析的方法,分析了三维隧道围岩、钢拱架的真实受力状态,模拟了有无临时仰拱时隧道的围岩压力和位移变化情况;探讨在软弱围岩地质情况下,有无临时仰拱对隧道应力场和位移场的影响,得出了施作临时仰拱对控制软弱围岩隧道的变形效果比较明显。结果表明:钢拱架右侧受力明显大于左侧,玉磨铁路曼么二号隧道受力不对称,可能存在偏压现象;实测数据与模拟数值变化趋势基本相同,验证了MIDAS/GTS能够有效地模拟隧道施工过程;通过模拟对比分析,施作临时仰拱时拱顶沉降值减小了15.5%,左拱腰位移减小了69%,右拱腰位移减小了66.7%,隧道围岩压力最大值为143.4 kPa,出现在拱顶位置,最大围岩压力减小了6.5%。     

北京北沙河湿地维管植物区系的研究

北京北沙河湿地有维管植物87种5变种1变型,共93个分类群,隶属于36科68属.其中蕨类植物1科,1属,3种;双子叶植物23科,40属,53种,1变种;单子叶植物12科,27属,31种,4变种,1变型.可分为10个分布区类型,包括世界广布属23属,热带属13属,温带性质的属32属.     

设计模式在变电站集中控制中的研究与应用

针对当前变电站信息化建设的需要,作者提出了一种基于SCADA(Supervision ControlAnd Data Acquisition)系统的小型变电站无人值守远程监控方案.重点在数据库服务器的软件.在该系统的开发过程中,采用了当前软件开发中流行的设计模式的思想.其中的组成模式旨在加强模块间的联系和模块操作的一致性;策略模式实现了多种访问行为的统一对外接口.这两种设计模式的使用加强了系统的健壮性、可扩展性和效率.     

Assessment of coral bleaching using symbiotic zooxanthellae density and satellite remote sensing data in the Nansha Islands,South China Sea

Coral bleaching,characterized by a significant loss of symbiotic zooxanthellae,is the primary cause of mass coral mortality and reef degradation throughout the world.The characteristics,processes,and resistance of corals to bleaching varies significantly and is dependent on environmental conditions.We documented a mass coral bleaching event in June 2007 at the Meiji and Zhubi Reefs,Nansha Islands (NS),South China Sea using ecological surveys and measurement of coral zooxanthellae density and sea surface temperatures (SST).More than 35 species of corals (between 0-20 m in depth) were bleached.These bleached corals accounted for 15.6% of total corals in the investigated quadrats.The branching corals Pocillopora and Acropora were the most vulnerable species whereas the massive corals Porites and Favia were more tolerant of the high SSTs.Surprisingly,we found no evidence of bleaching in Agariciidae corals suggesting that this family is resistant to thermal stresses.The bleached corals had lost 72%-90% of their symbiotic zooxanthellae.Furthermore,corals that had no visual signs of bleaching had also lost 31%-53% of their zooxanthellae suggesting that most corals were experiencing the early stage of bleaching.The monthly mean SST during June 2007 was 30.8°C,the highest since 1998.Based on measurements of SST and the Hotspots and DHW data (NOAA),we conclude that it the extremely high SSTs triggered this coral bleaching event.Our results suggest that the previously accepted temperature thresholds used to predict coral bleaching based on satellite data are likely to underestimate the extent and intensity of coral bleaching,at least in the NS.