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121.
1IntroductionIn the early 1960s, glaciers in western China were classified into maritime- and continental-types by different glacial environment and physical characteristics (Shi and Xie, 1964). With extensive glaciological investigations in the western regions (Lanzhou Institute of Glaciology and Geocryology of CAS, 1988), Lai and Huang (1990) suggested a new classification of temperate, subpolar and quasipolar glaciers, corresponding to the maritime-, subcontinental- and extremely contin…  相似文献   
122.
Local Modeling模式及其在月径流预测中的应用   总被引:5,自引:2,他引:5  
Local Modeling方法是一种动力系统预测方法,将其应用于河西内陆区黑河干流出山口莺落峡水文站月平均流量的中长期预测预报,取得了较为理想的成果。预测试验的结果表明,该预测模型有较高计算精度,尤其适用于非主汛期各月的月平均流量的预测;对于主汛期6~9月的月平均流量的预测,在考虑前期来水与预见期内降水的影响后,亦可获到较为理想的预测结果。可以认为,该方法的预报精度达到了水文情报预报规范的要求,Local Modeling方法的应用,将为西北干旱地区河川径流的中长期预报提供了一个新的途径。  相似文献   
123.
流动VLBI天线系统噪声温度及天线效率测量   总被引:1,自引:0,他引:1  
我国自行研制的第一套流动VLBI系统——DCW—01型流动VLBI测量仪,目前已在国家重大科学工程“中国地壳运动观测网络”中投入使用。在流动VLBI的观测试验中,天线系统噪声温度和天线效率是观测前系统调试和检测的两项重要内容。天线系统噪声温度是衡量流动VLBI观测系统内部噪声程度的特性指标;天线效率反映了天线系统对到达天线能量的刊用率,在很多计算公式中是一个很重要的参数。因此,精确地测量它们的值是进行相关处理和计算的前提。文中结合我国流动VLBI观测站的研制与建设,介绍了流动VLBI测量仪的天线及接收机系统,并详细阐述了其天线系统噪声温度和天线效率的测量。  相似文献   
124.
Glacier inventory compilation during the past 20 years and modifications of that for the Eastern Pamir and Banggong Lake indicate that there are 46,342 modern glaciers with a total area and volume of 59415 km2 and 5601 km3 respectively in China. These glaciers can be classified into maritime and continental (including sub-continental and extremely continental) types. Researches show that glaciers in China have been retreating since the Little Ice Age and the mass wastage was accelerated during the past 30 to 40 years. Being an important part of glaciological studies in China, ice core climatic and environmental studies on Tibetan Plateau and in the Antarctica have provided abundant, high resolution information about past climatic and environmental evolution over the Tibetan Plateau and Antarctica. Except for different parameters recorded in ice cores relating to climate and environment changes on Tibetan Plateau, records from ice cores extracted from different glaciers show that the discrepancies in climatic and environmental changes on the north and south parts of the plateau may be the consequence of different influencing effects from terrestrial and solar sources. Glaciological and meteorological phenomena imply that Lambert Glacier valley is an important boundary of climate in the east Antarctica, which is thought to be connected with cyclonic activities and Circum-polar Waves over the Antarctica.  相似文献   
125.
This paper presents the detailed results and analyses on the ecological footprints and bio-capacities of the individual cities and the province as a whole for the year 2001, providing a clear picture of sustainability for the province. Results show that the ecological footprints of most cities in Liaoning exceeded their respective bio-capacities, incurring high ecological deficits. The ecological deficit of the province as a whole was 1.31 ha/cap. Those cities with resources extraction and/or primary material-making as their major industries constitute the "ecologically black band", whose ecological deficits ranged from 2.45 to 5.23 ha/cap, the highest of all cities in the province. Fossil energy consumption was the major source of footprint amounting to 1.63 ha/cap at the provincial level, taking up 67.3% of the total. For cropland, modest ecological surpluses occurred in Jinzhou, Tieling, Huludao, and Panjin while modest ecological deficits in Dalian, Benxi, Fushun, and Dandong, resulting in an overall surplus for the province. Liaoning had a certain level of surplus in fishing ground (water area), mainly distributed in the coastal cities of Dalian, Panjin, Huludao, Yingkou, Jinzhou, and Dandong. Most cities had a small ecological deficit in pasture and all had a small ecological surplus in forest. The eco-efficiency, expressed as GDP value per hectare of footprint, exhibits high variations among the cities, with the highest (Shenyang) more than 10 times the lowest (Fuxin). Cities with manufacture, high-tech, and better developed service industries had high eco-efficiency, while those with resources extraction, primary material-making, and less developed service industries had low eco-efficiency. Based on the components and geographical distribution of ecological footprint, strategic policy implications are outlined for Liaoning's development toward a sustainable future.  相似文献   
126.
内蒙古中西部地区震源参数和场地响应反演   总被引:15,自引:0,他引:15       下载免费PDF全文
采用Atkinson方法,基于遗传算法,利用呼和浩特数字地震台网7个子台记录的9次质量较高的地震事件资料,计算了内蒙古中西部地区的品质因子Q值和非弹性衰减系数c(f)。在所研究的频率范围内,前者和频率.厂有很好的线形关系:Q(f)=116.8f^1.000后者与频率.厂的变化关系不明显。在此基础上采用Moya方法反演了7个地震台的场地响应和地震的震源参数,并对它们之间的相互关系进行了讨论。结果显示在所研究的频率域内7个基岩台站的场地均不同程度的存在放大作用,其次震源参数间具有较好的线性关系。本文还详细介绍了Atkinson方法和Moya方法的原理和计算步骤。  相似文献   
127.
本文以巩固和发挥大地形变地震监测预报基础地位和作用、积极推进中国西部防震减灾事业可持续性和协调性发展为主旨,回顾了西部地区20世纪70年代初至“九五”前期大地形变监测与地震预测研究工作基础,介绍了“九五”后期至今大地形变监测与地震预测研究的主要进展,并对该领域发展中所面临的一些问题进行了初步探讨。  相似文献   
128.
合肥盆地钻井地层的同位素测年与地层划分   总被引:3,自引:0,他引:3  
合肥盆地内部中、新界地层大面积被第四系覆盖,其地层的时代与划分主要依赖已有的6口深井地层资料。由于缺乏可靠的化石记录,这6口深井地层时代与划分一直存在着很大的分歧,制约了对该盆地的油气勘探与远景评价。本文利用这6口深井泥岩类岩屑中自生伊利石,在其结晶度分析基础上,进行了K-Ar同位素测年,成功地获得了不同深度上的地层形成时代。据此地层年龄,文中对这6口深井所钻遇的地层进行了重新的划分。  相似文献   
129.
山西临汾盆地及邻区地震时空分布特征初探   总被引:2,自引:0,他引:2  
临汾盆地是山西断陷带中地壳结构最复杂、地震活动最强烈的地区.有史料记载以来,发生过M≥4 3/4地震16次,其中8级地震1次,7 3/4级地震1次,6 3/4级与6 1/2级地震各1次,5级~5 1/2级地震11次,4 3/4 级地震1次.  相似文献   
130.
The spatial/temporal variation information of atmospheric dynamic-chemical processes at observation site points of the "canopy" boundary of Beijing urban building ensemble and over urban area "surface", as well as the seasonal correlation structure of the gaseous and particulate states of urban atmospheric pollution (UAP) and its seasonal conversion feature at observation points are investigated, using the comprehensive observation data of the Beijing City Air Pollution Observation Experiment (BECAPEX) in winter and summer 2003 with a "point-surface" combined research approach. By using "one dimension spatial empirical orthogonal function (EOF)" principal component analysis (PCA) mode, the seasonal change of gaseous and particulate states of atmospheric aerosols and the association feature of pollutant species under the background of the complicated structure of urban boundary layer (UBL) are analyzed. The comprehensive analyses of the principal components of particle concentrations,gaseous pollutant species, and meteorological conditions reveal the seasonal changes of the complex constituent and structure features of the gaseous and particulate states of UAP to further trace the impact feature of urban aerosol pollution surface sources and the seasonal difference of the component structure of UAP. Research results suggest that in the temporal evolution of the gaseous and particulate states of winter/summer UAP, NOx, CO, and SO2 showed an "in-phase" evolution feature, however, O3 showed an "inverse-phase" relation with other species,all possessing distinctive dependent feature. On the whole, summer concentrations of gaseous pollutants CO, SO2, and NOx were obviously lower than winter ones, especially, the reduction in CO concentration was most distinctive, and ones in SO2 and NOx were next. However, the summer O3 concentration was more than twice winter one. Winter/summer differences in PM10and PM2.5 particle concentrations were relatively not obvious, which indicates that responses of PM10 and PM2.5 particle concentrations to the difference of winter/summer heating period emission sources are far less distinctive than those of NOx, SO2, and CO. The correlation feature of winter/summer gaseous and particulate states depicts that both PM10 and PM2.5 particles were significantly correlated with NOx, and their correlations with NOx are more significant than those with other pollutants. Through PCA, it is found that there was a distinctive difference in the principal component combination structure of winter/summer PM10 and PM2.5 particles: SO2 and NOx dominated in the principal component of winter PM10 and PM2.5 particles; while CO and NOx played the major role in the principal component of summer PM10 and PM2.5 particles. For winter/summer PM10 and PM2.5 particles, there might exist the gaseous and particulate states correlation structures of different "combinations" of such dependent pollutant species. Research results also uncover that the interaction processes of gaseous and particulate states were also related with the vertical structure of UBL, that is to say, the low value layer of UBL O3 concentration was associated with the collocation of atmospheric vertical structures of the low level inversion,inverse humidity, and small wind, which depicts summer boundary layer atmospheric character, i.e.the compound impact of the dependent factor "combination" of wind, temperature, and humidity elements and their collocation structure on the variations of different gaseous pollutant concentrations. Such a depth structure of the extremely low value of O3 concentration in the UBL accords with its "inverse-phase" relation with other gaseous pollutant species. The PCA of meteorological factors associated with PM10 and PM2.5 concentrations also reveals the sensitivity of PM10 and PM2.5 concentration to the combinatory feature of local meteorological conditions.  相似文献   
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