统一地址赋能社会治理的关键技术     

陈超益  汝虎  焦超锋 《测绘通报》2021,(6):134-138,146

统一地址的概念于近些年才被提出,其主要本质和意义是在充分尊重现有各部门行业标准地址的基础上,作为社会治理要素有效关联融合的“桥梁”,为摸清底数、精准施策等精细治理工作提供支撑,是测绘地理信息技术在社会治理数字化、智能化领域的创新应用。本文针对统一地址在建设过程中的关键技术进行初步研究,并简单介绍了杭州市的实际应用情况。  相似文献   

大型通江湖泊洞庭湖的鱼类物种多样性及其时空变化   总被引：12，自引：3，他引：9  

茹辉军  刘学勤  黄向荣  宁应之  王洪铸 《湖泊科学》2008,20(1):93-99

为了解通江湖泊鱼类物种多样性现状,于2004年3月-2004年12月和2005年5月对洞庭湖城陵矶、岳阳和沅江三个区域的鱼类进行逐月调查.共鉴定鱼类69种,隶属6目14科44属,其中59.4%为鲤科鱼类.以种类数和多样性指数分析了群落多样性特征,结果表明洞庭湖鱼类种类多样性较高,且时空变化较大.一般地,湖区与长江干流的距离越近,种类数达到峰值的时间就越早;鱼类多样性在春夏季高于秋冬季,在南洞庭湖高于其它两个区域.以优势度>5000为标准,全湖有17种优势种,其中80.0%为湖泊定居性鱼类.在生态类群方面,湖泊定居性鱼类种类最多,占总种类数的74.0%;江湖洄游性鱼类最少,占13.0%.对比分析显示,由于生境丧失、天然苗种资源衰退和过度捕捞等原因,洞庭湖鱼类多样性较20世纪70年代明显下降,洄游鱼类种类数减少;通江湖泊鱼类多样性明显高于阻隔湖泊,表明江湖阻隔造成鱼类多样性下降,因此,加强江湖连通是保护鱼类多样性的有效手段.  相似文献   

Discussion on the Cenozoic tectonic evolution and dynamics of southern Tibet     

LIU Demin  YANG Weiran  GUO Tieying  RU Jiangtao  XIONG Aimin 《地学前缘》2020,27(1):275-286

Opening-closing tectonics is a new idea for exploring the global tectonics, which holds that every tectonic movement of all materials and geological bodies on earth is characterized by opening and closing. The opening -closing tectonic view can be used to explain some geological phenomena developing in continents which cannot be reasonably explained by the theory of plate tectonics. Based on the available basic geological data and combining with the opening-closing view, we analyzed the divisions and characteristics of tectonic units in South Tibet, and propose that Tibet can be divided into gravitational detachment and detachment fault zones, which are superimposed thrust fault zones and reconstructed normal fault zones, respectively. Although the mainstream opinion believed that the Tibetan Plateau is formed by collision-compression orogenesis, field investigation revealed the existence of the Rongbu Temple normal fault in the1970s. We consider that the Rongbu Temple normal fault and the Main Central Thrust (MCT) were formed earlier than the South Tibet detachment fault, and the former two faults constitute the two boundaries of the southern Tibet extrusion structure. The South Tibet detachment fault partially superimposes on the MCT and manifests a relatively high angle in following the Rongbu Temple normal fault north of the Chomolangma. We suggest that the three fault systems are the products of different periods and tectonic backgrounds. The tectonic units, such as klippes and windows identified by previo us researchers in southern Tibet, belong to thrust fault system but usually have no obvious extrusion or thrust characteristics; however, they are characterized by missing strata columns as younger strata overlapping the older ones. These klippes and windows should be the results of later gravitational decollement and must be characterized as extensions and slips, respectively. Based on opening-closing theory, we suggest that since the Cenozoic the study area had undergone multistage development, which can be divided into the oceanic crust expansion (opening) and subduction (closing) and the continental collision (closing) and intracontinental extension (opening) stages. Geothermal energy from the deep earth, gravitational potential energy from the earth’s interior, and additional stress energy from tectonic movements, all played a key role in the multistage tectonic evolutionary process.  相似文献   

山东齐河—禹城地区重磁场特征及找矿预测     

周明磊  汝亮  朱裕振  于长春  吴成平  高志军  张文艳  邵玉宝 《物探与化探》2021,(2):301-307

齐河—禹城地区已钻探见富铁矿深度748～1 542m,第四系覆盖厚度超过500m,富铁矿体地球物理场信息弱,找矿难度大.为了进一步缩小找矿靶区,为钻孔部署提供依据,通过研究矿致异常的航空和地面重磁异常特征,利用化极、垂向导数、总梯度模等方法,提取富铁矿直接找矿信息,建立了本区地球物理找矿标志,确定了7处重点勘查区.本项...  相似文献   

海胆配子及胚胎发育模型在农药类环境激素筛选中的应用     

姚丹  汝少国 《海洋科学》2009,33(8):93-96

我国农药生产和使用量较大,农药污染问题日益突出,薛秀玲等[1]报道福建省闽江口和泉州湾的缢蛏和牡蛎样品中的敌敌畏、甲胺磷平均质量分数分别为0.80×10-3叫和2.58×10-9(湿质量),检出率较高.  相似文献