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331.
黔西北高原药用植物区系的初步研究   总被引:5,自引:1,他引:4  
何顺志 《贵州科学》1993,11(4):12-16
本文论述了黔西北高原药用植物的种类组成与区系特征,并分析了它们的分布特点。该区药用植物资源丰富,共有196科,672属,1474种(含种下等级)。其中,古老和原始的科、属不乏其代表。从药用种子植物属的分布区类型的比较分析,该区具有我国15个种子植物属的分布区中的全部类型,表明了与世界各地区植物区系的联系程度。另一方面,该地区的植物区系虽含有丰富的热带成分,但明显偏重于温带性质,这种温带性质可能与该区的地理位置与海拔高度有着重要的联系。  相似文献   
332.
“中国北方长城地带”青铜时代居民的人类学资料表明。匈奴人的人种构成具有突出的地域性,不同地区的匈奴人基本延续了较早时期的人种类型。“中国北方长城地带”东周时期南下的牧人在人种类型上属于“古蒙古高原类型”,来源上应与蒙古高原以及外贝加尔石板墓的居民有一定的渊源关系。到战国晚期以后,当长城以北强大的匈奴联盟形成的时候,这部分古代居民很有可能最终加入到了匈奴联盟当中。  相似文献   
333.
昌耀的诗歌创作开始于20世纪50年代,他的抒情风格几经历变,但总是超越凡俗,卓然独立于高原之上,以雄奇高邈,以及现代意识塑造了自己的诗歌品质。本文试图从高原情思,史诗气质,现代意识三个方面探讨昌耀诗歌的抒情风格。  相似文献   
334.
During the years 2006–2009,lakes in the Qinghai-Tibetan Plateau(QTP)were investigated using satellite remote sensing strategies.We report the results of this investigation as well as follow-up research and expanded work.For the investigation,we mainly focused on lakes whose areas are more than 1 km2.The remote sensing data that we used included 408 scenes of CBERS CCD images and 5 scenes of Landsat ETM?images in Qinghai Province and Tibet Autonomous Region.All these data were acquired around years 2005–2006.Besides remote sensing images,we also collected 1,259 topographic maps.Numbers and areas of lakes were analyzed statistically,which were then compared with those coming from the first lake investigation(implemented between the1960s and 1980s).According to our investigation,up to and around year 2005–2006,the total number of lakes in the QTP was 1,055(222 in Qinghai and 833 in Tibet),accounting for more than 30%of that of China.Thirty newborn lakes with area[1 km2were found,and 5 dead lakes with initial area[1 km2were also found.Among those 13 big lakes([500 km2),Yamzhog Yumco had seriously shrunk,and it has continued to shrink in recent years;Qinghai Lake had shrunk during the period,but some new researches indicated that it has been expanding since the year 2004;Siling Co,Nam Co,and Chibuzhang Co had expanded in the period.We divided the newborn lakes into six categories according to their forming reasons,including river expansion,wetland conversion,etc.The changes of natural conditions led to the death of four lakes,and human exploitation was the main reason for the death of Dalianhai Lake in Qinghai.We picked out three regions which were sensitive to the change of climate and ecological environment:Nagqu Region,Kekexili Region,and the source area of the Yellow River(SAYR).Lakes in both Nagqu and Kekexili have been expanded;meanwhile,most lakes in the SAYR have obviously been shrunk.These regional patterns of lake changes were highly related to variations of temperature,glacier,precipitation,and evaporation.Our investigation and analysis will provide references for researches related to lake changes in the QTP and the response to climate fluctuations.  相似文献   
335.
A large number of stone knives have been recovered from Neolithic archaeological sites in East Asia. However, direct evidence regarding the functions of the stone knives has been scarce, and hence, their functions have remained controversial. In this study, we recovered and analysed ancient starch grains and phytoliths from residues adhering to stone knives excavated from the Lajia site, Qinghai Province, northwest China, thus providing direct evidence for the functions of the knives. Our anal- yses were based on the following: (1) an assemblage of 278 identifiable starch grains, representing grains from the stems of foxtail millet (Setaria italica) and broomcorn millet (Panicum miliaceum) (65.1% of the total) and the stems of Hordeum and Triticum species (3.6 % of the total), and (2) an assemblage of 361 identifiable phytoliths, the majority of which were from the stems and leaves of plants such as Panicoideae and related taxa (96 % of the total). Our study demonstrates that one of the functions of the stone knives was the harvesting crops. In addition, a few starch grains from food legumes and roots (3.4 % of the total) indicate that the stone knives were also likely used to process, peel and cut some foods.  相似文献   
336.
Widespread lakes on the Tibetan Plateau (TP) are valuable archives for investigating climate and environment changes, which could provide essential information on the mechanisms of past climate changes on the TP and their interaction with the global climate systems. However, there is a lack of in-depth investigation of modern limnological processes in the Tibetan lakes, which hampers the understanding of paleolimnological records and lake ecosystem succession. In this study, we performed continuous temperature monitoring at two lakes, Bangong Co, a freshwater lake in the western TP, and Dagze Co, a brackish lake in the central TP, in order to characterize the patterns of seasonal temperature variability, stratification, and mixing. Temperature data for an entire hydrological year demonstrate that Bangong Co is a dimictic lake and that Dagze Co is a meromictic lake. The higher salinity in the deep water at Dagze Co prevents the lake from overturning completely, and this finding is supported by simulations using a physical limnological model Lake Analyzer. Continuous lake water temperature monitoring provides fundamental data for classifying Tibetan lakes, as well as the hydrological basis for understanding their pa- leolimnological records and ecosystem succession.  相似文献   
337.
本文旨在借助青海东部地区危房改造建设的有利时机,推进农房绿色民居建设,提出该地区民居建造不但应借鉴、传承原有的符合地域气候等条件的材料及技术,同时有机结合现代绿色建造技术,改造、提升其在规划、建筑结构设计及建筑节能方面的技术做法.  相似文献   
338.
顾佳佳  武威 《河南科学》2014,(6):1073-1077
利用常规地面观测资料、高空资料以及卫星云图资料,通过2010年7月与2011年7月的云图对青藏高原及周边地区对流云和中尺度对流系统的活动进行初步研究,分析了青藏高原上空对流云的特征.结果表明:①青藏高原上的对流过程是在特定的环流背景下受西风带500 hPa低槽、700 hPa切变线、850 hPa低涡以及地面图上中尺度低涡和地面静止锋的共同影响造成的;②对流云产生不仅与水汽条件有关,还与不稳定层结条件和抬升力条件即触发机制有关;③对流云的发生发展具有明显的日变化.  相似文献   
339.
The anisotropy of magnetic susceptibility (AMS) is a rapid and precise tool for determining paleowind directions. During the past several decades, AMS has been used for determining paleowind directions of Chinese loess. The AMS for a Ioess-paleosol profile in early Quaternary at Longdan in the Linxia Basin, Gansu Province, northeastern fringe of Qinghai-Xizang (Tibetan) Plateau has been obtained. The primary results show that the AMS of the Longdan profile has its typical normal eolian dust deposit. The AMS is mainly controlled by magnetic foliation (F) and the shape parameter of the AMS ellipsoid is oblate. The declination of maximum susceptibility (K1) was used to determine the paleowind direction of that area in early Quaternary and it was found that the paleowind direction is biased towards NW-SE.  相似文献   
340.
We introduced the observations and researches using a Satellite Laser Ranging (SLR) system with high precision, which was designed and made in China and installed in the Observatory of San Juan Uni- versity, Argentina, the capability of the system and the achievement of the cooperative procedure be- tween China and Argentina. The SLR station in San Juan, set up by China and Argentina, is quite sig- nificant for improving the distribution of SLR stations and enhancing the orbital coverage of the whole earth. Since the SLR system started to work in the Observatory of San Juan University in the beginning of 2006, the operation is rather good, and rich data with high precision have been obtained. Further plan of the cooperation for the near future is also presented.  相似文献   
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