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1.
Matthias Kuhle 《山地科学学报》2006,3(2):91-124,i0001,i0002
1 Introduction, Methods of Evidence and Characteristics of the Investigation Areas The aim of this study was to find geomorph- ological and sedimentological indicators of a past glaciation. In addition to the reconstruction of the maximum extent of Ice Age glacier cover, field investigations combined with panorama photo- graphs and laboratory analyses of samples werefocused on the evidence of glacier trim-lines and -thicknesses. This is the regional continuation of a detailed and spatially …  相似文献   

2.
Editorial Note: The first section of this article was published in June 2006 (cf. pages 91-124 in No. 2, Vol. 3), and the publishing here is its sequel, which includes 22 Figures (i.e. Figures 9-30). two photos (Photo I and 2) and one table (i.e. Table 7). The figures before No.9 mentioned in the text of this part were published in previous issue, and please refer to them while reading. We sincerely apologize to you for any inconvenience this arrangement may have caused you.  相似文献   

3.
Effect of temperature and irradiance on growth and reproduction of Enteromorpha prolifera that bloomed offshore along the Qingdao coast in summer 2008, was studied. It was showed that E. prolifera propagated mainly asexually with specific growth rate (SGR) of 10.47 at 25°C/40 μmol m-2s-1. Under this condition, gametes with two flagellate formed and released in 5 days. At the beginning of the development, the unicell gamete divided into two cells with heteropolarity, and then the apical cell developed into thalli primordial cells, whereas the basal cell developed into rhizoid primordial cells. In 8-day culture, the monoplast gamete developed into juvenile germling of 240 μm in length. Unreleased gametes can develop directly within the alga body. E. prolifera could either reproduce through lateral branching or fragmenting except apomixis revealed by Microscopic observation. On aged tissue of E. prolifera, although the degraded pigments partially remained in faded algal filaments, numerous vegetative ceils could still divide actively in the algal tissues.  相似文献   

4.
Effect of temperature and irradiance on growth and reproduction of Enteromorpha prolifera that bloomed offshore along the Qingdao coast in summer 2008, was studied. It was showed that E. prolifera propagated mainly asexually with specific growth rate (SGR) of 10.47 at 25℃/40 μmol m^-2s^-1. Under this condition, gametes with two flagellate formed and released in 5 days. At the beginning of the development, the unicell gamete divided into two cells with heteropolarity, and then the apical cell developed into thalli primordial cells, whereas the basal cell developed into rhizoid primordial cells. In 8-day culture, the monoplast gamete developed into juvenile germling of 240 μm in length. Unreleased gametes can develop directly within the alga body. E. prolifera could either reproduce through lateral branching or fragmenting except apomixis revealed by Microscopic observation. On aged tissue of E. prolifera, although the degraded pigments partially remained in faded algal filaments, numerous vegetative cells could still divide actively in the algal tissues.  相似文献   

5.
Mt.Everest (27°54' N,86°54' E),the highest peak,is often referred to as the earth's 'third' pole,at an elevation of 8844.43 m. Due to the difficult logistics in the extreme high elevation regions over the Himalayas,observational meteorological data are very few on Mt. Everest. In 2005,an automatic weather station was operated at the East Rongbuk glacier Col of Mt. Everest over the Himalayas. The observational data have been compared with the reanalysis data from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR),and the reliability of NCEP/NCAR reanalysis data has been investigated in the Himalayan region,after the reanalyzed data were interpolated in the horizontal to the location of Mt. Everest and in the vertical to the height of the observed sites. The reanalysis data can capture much of the synoptic-scale variability in temperature and pressure,although the reanalysis values are systematically lower than the observation. Furthermore,most of the variability magnitude is,to some degree,underestimated. In addition,the variation extracted from the NCEP/NCAR reanalyzed pressure and temperature prominently appears one-day lead to that from the observational data,which is more important from the standpoint of improving the safety of climbers who attempt to climb Mt. Everest peak.  相似文献   

6.
Because of the large number and remoteness, satellite data, including microwave data and optical imagery, have commonly been used in alpine glaciers surveys. Using remote sensing and Geographical Information System (GIS) techniques, the paper presents the results of a multitemporal satellite glacier extent mapping and glacier changes by glacier sizes in the Mt. Qomolangma region at the northern slopes of the middle Himalayas over the Tibetan Plateau. Glaciers in this region have both retreated and advanced in the past 35 years, with retreat dominating. The glacier retreat area was 3.23 km2 (or o.75 km^2 yr^-1 during 1974 and 1976, 8.68 km^2 (or 0.36 km^2 yr^-1 during 1976 and 1992, 1.44 km^2 (or 0.12 km^2 yr^-1) during 1992-2ooo. 1.14 km^2 (or 0.22 km^2 yr^-1 during 2000-2003, and 0.52 km^2 (or 0.07 km^2 yr^-1 during 2003-2008, respectively. While supra-glacier lakes on the debris-terminus of the Rongbuk Glacier were enlarged dramatically at the same time, from 0.05 km^2 in 1974 increased to 0.71 km^2 in 2008, which was more than 13 times larger in the last 35 years. In addition, glacier changes also showed spatial differences, for example, glacier retreat rate was the fastest at glacier termini between 5400 and 5700 m a.s.l than at other elevations. The result also shows that glaciers in the middle Himalayas retreat almost at a same pace with those in the western Himalayas.  相似文献   

7.
以珠穆朗玛峰国家自然保护区为研究区域,选取2009年23幅MODIS NDVI影像,采用傅里叶变换的HA-NTS算法去除云干扰,并重构NDVI时间序列图像.(1)根据研究区沼泽湿地与其他地物类型物候特征的差异,利用光谱角制图方法(SAM)获取了研究区2009年沼泽湿地的分布图.研究区沼泽湿地共有2 481.13km2,...  相似文献   

8.
Phenological background information for alpine species is limited from extremely high altitudes. Flowering and fruiting phenology was monitored for 24 plant species at 5,180 m a.s.l. near the base camp area on the north slope of Mt. Qomolangma (Mt. Everest) in Tibet, western China. The dates of first flowering, peak flowering, end of flowering, first fruiting, peak fruiting and flowering period were recorded. There was a wide variation in onset of flowering, long flowering duration, a relative synchrony bet...  相似文献   

9.
Tibetan spruce (Picea smithiana) is an endemic species of the Himalayas,and it distributes only in a re-stricted area with very low number.To address the lack of detailed distributional information,we used maximum en-tropy (Maxent) niche-based model to predict the species' potential distribution from limited occurrence-only records.The location data of P.smithiana,relative bioclimatic variables,vegetation data,digital elevation model (DEM),and the derived data were analyzed in Maxent.The receiver operating ...  相似文献   

10.
Mt. Everest is often referred to as the earth's 'third' pole. As such it is relatively inaccessible and little is known about its meteorology. In 2005, an automatic weather station was operated at North Col (28°1′ 0.95" N, 86°57′ 48.4" E, 6523 m a.s.l.) of Mt. Everest. Based on the observational data, this paper compares the reanalysis data from NCEP/NCAR (hereafter NCEP-Ⅰ) and NCEP-DOE AMIP-Ⅱ (NCEP- Ⅱ), in order to understand which reanalysis data are more suitable for the high Himalayas with Mr. Everest region. When comparing with those from the other levels, pressure interpolated from 500 hPa level is closer to the observation and can capture more synoptic-scale variability, which may be due to the very complex topography around Mt. Everest and the intricately complicated orographic land-atmosphereocean interactions. The interpolation from both NCEP-Ⅰ and NCEP-Ⅱ daily minimum temperature and daily mean pressure can capture most synopticscale variability (r〉0.82, n=83, p〈0.001). However, there is difference between NCEP-Ⅰ and NCEP-Ⅱ reanalysis data because of different model parameterization. Comparing with the observation, the magnitude of variability was underestimated by 34.1%, 28.5 % and 27.1% for NCEP-Ⅰ temperature and pressure, and NCEP-Ⅱ pressure, respectively, while overestimated by 44.5 % for NCEP-Ⅱ temperature. For weather events interpolated from the reanalyzed data, NCEP-Ⅰ and NCEP-Ⅱ show the same features that weather events interpolated from pressure appear at the same day as those from the observation, and some events occur one day ahead, while most weather events and NCEP-Ⅱ temperature interpolated from NCEP-Ⅰ happen one day ahead of those from the observation, which is much important for the study on meteorology and climate changes in the region, and is very valuable from the view of improving the safety of climbers who attempt to climb Mt. Everest.  相似文献   

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