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1.
FLOROGEOGRAPHYOFMIREPLANTSINSOUTHERNPARTOFQINGHAIXIZANGPLATEAUANDITSADJACENTAREASZhaoKuiyi(赵魁义)ChangchunInstituteofGeography...  相似文献   

2.
The flora of the Qinghai-Xizang Plateau belongs to the floristic subkingdom of the Holarctic plant kingdom. The Xizang part of this subkingdom can be divided into 4 plant regions. 1) the Yarlung Zangbo River valley region. There are 1,003 species of seed plants, making up 19.38% of the total species in Xizang, and 159 endemic species, 15.89% of the total seed plants. The flora originates mainly from the East Himalayas and the Hengduan Mountains. 2) The Tanggute region. There are 349 species of seed plants and 10 endemic species. The flora represents an intermediate one between the Qinghai-Xizang Plateau and the Hengduan Mountains.3) The Qiangtang region. There are 255 species of seed plants and 18 endemic species. The flora derived from the Himalayan flora and mixed with a great number of Tethysian elements. 4) the Ali region. There are 547 species of seed plants and 41 endemic species. The flora seems to be closely related to Tethysian one.  相似文献   

3.
1 INTRODUCTIONFlora refers to the sum total ofthe plant species found ina specified region, and is the integration of florogenesis,plant evolution and historical geographical change.Henan Province is located in Central China Plains(comprising the middle a…  相似文献   

4.
Based on field investigations, laboratory analyses and 14C dating, this paper discusses the laws of the formation and development of the paleosols in the northeast region of the Qinghai-Xizang Plateau since Late Pleistocene. The authors reconstruct basic conditions of climate, vegetation, soil and natural zones during the three periods in which the paleosols were formed, i.e. the last interglacial of the Late Pleistocene, warm stage of Late Glacial and the Optimum of Holocene. Finally, this paper discusses the relationship between the paleosols and the uplift of the Qinghai-Xizang Plateau.  相似文献   

5.
PALEOSOLSANDTHEIRREFLECTIONOFTHEENVIRONMENTALCHANGESINTHENORTHEASTREGIONOFTHEQINGHAI-XIZANGPLATEAU徐叔鹰,潘保田PALEOSOLSANDTHEIRREF...  相似文献   

6.
EastChinaisoneoftherichestregionsinplantlifeinEastAsiaanditsfloraisthemainpartofSino-Japanesefloristicregion,whichhasattractedtheattentionofmanybotanistsbothathomeandabroad,suchasHuXiansu(1936),LiHuilin(1950,1953),StewardA.N.(1958),WangJingkiang(1988),WangWencai(1992),Wusugong(1987),WuZhengyi(1979)andXieGuowen(1991a,1993),etal.AnumberofpapersdealingwithEastAsian-EasternNorthAmericanphytogeographicalrelationshipshavebeenpublished(Bouffordf1983).However,thefloristicrelationsbetweenEas…  相似文献   

7.
Based on the field investigation in August 2001 and August 2002, digital China Vegetation Map in 2001 and Qinghai-Xizang(Tibet) Plateau Vegetation Regionalization Map in 1996, vegetation characteristics along two sides of Qinghai-Xizang highway and railway are studied in this paper. Meanwhile, the impact of Qinghai-Xizang highway and railway constructions on the vegetation types are analyzed using ARCVIEW. ARC/1NFO and PATCH ANALYSIS. It was found that: 1) Qinghai-Xizang highway and railway span 9 latitudes, 12 longitudes and 6 physical geographic regions (East Qinghai and Qilian mountain steppe region, Qaidam mountain desert region,South Qinghai-Xizang alpine meadow steppe region. Qiangtang alpine steppe region, Golog-Nagqu alpine shrubmeadow region and South Xizang mountain shrub steppe region); 2) the construction of Qinghai-Xizang highway and railway destroyed natural vegetation and landscape, especially in 50m-wide buffer regions along both sides of the roads, it was estimated that the net primary productivity deceased by about 30 504.62t/a and the gross biomass deceased by 432 919.25-1 436 104.3t. The losing primary productivity accounted for 5.70% of the annual primary productivity within lkm-wide buffer regions (535 005.07-535 740.11t/a), and only 0.80%-0.89% of that within 10km-wide buffer regions (3 408 950.45-3 810 480.92t/a). The losing gross biomass was about 9.47%-17.06% of the gross biomass within lkm-wide buffer regions (7 502 971.85-25 488 342.71t), and only 1.47%-2.94% of that within 10km-wide buffer regions (43 615 065.35-164 150 665.37t).  相似文献   

8.
There are 463 species of woody plant, belonging to 166 genera and 70 families in Shanxi, North China. The floristic composition types of genera and species are abundant, in which the compositions distributed in temperate zones (including North Temperate, Old World Temperate and Temperate Asia), having 62 genera, are dominant and account for 38.27% in total genera (except for Cosmopolitan), and they are major constructive or dominant species of vegetation in Shanxi. The floristic compositions of woody plants of Shanxi, Hebei, Beijing, Shandong, Henan, Jiangxi and Inner Mongolia were studied comparatively by using diversity index, principal component analysis (PCA) and group-average clustering, respectively. The floristic composition of Shanxi was considerably similar to that of Hebei, Beijing and Shandong because they shared a lot of genera, specially genera distributed in temperate regions, such as Rosa, Quercus, Populus, Salix, Acer, Ulmus, Pinus etc. and their eco-environment were considerably similar. However, the flora of Shanxi was comparatively different from that of Henan, Jiangxi and Inner Mongolia by reason that there were distinct differences among their eco-geographic conditions, floristic compositions and constructive or dominant species of dominant vegetation types. Supported by Shanxi Returned Oversea Scholar Foundation, China  相似文献   

9.
邢福武,李泽贤,叶华谷,陈炳辉,吴德邻ASTUDYONTHEFLORISTICPLANTGEOGRAPHYOFXISHAISLANDS,SOUTHCHINA¥XingFuwu;LiZexian;YeHuagu;ChenBinghui;WuDelin(...  相似文献   

10.
ASTUDYONTHEFLORAOFWOODYPLANTSOFSHANXIANDTHERELATIONSHIPAMONGTHEFLORAOFSHANXIANDSOMEREGIONS,CHINA①ZhangFeng(张峰)DepartmentofLif...  相似文献   

11.
Since the late 1950's, many Chinese scientists have explored the remains of the Quaternary glaciation in the Qinghai-Xizang (Tibet) Plateau and its surrounding mountains. In the main, 3-4 glaciations have been recognized. The largest one occurred in the Late Middle Pleistocene with piedmont glaciers, ice caps and trellis valley glaciers in many high peak regions. But here is no evidence of a unified ice sheet covering the whole plateau as described by M. Kuhle. Due to the further uplifting of the Himalayas and Qinghai-Xizang Plateau the climate became progressively drier, diminishing the extension of glaciers during the Late Pleistocene. The elevation of the snow line during the Last Glaciation was about 4,000 m on the south, east and northeast edges of the plateau and ascended to 5500 m on the hinder northwest of the plateau. The thermal effect of the big plateau massif, the sharp increase of aridity from the southeast rim to the northwest inland area and the abrupt decrease of precipitation during the  相似文献   

12.
THE FLORISTIC CHARACTERISTICS OF THE TROPICAL RAINFOREST IN XISHUANGBANNA ZhuHua(朱华)(XishuangbannaTropicalBotanicalGarden,the...  相似文献   

13.
Since the late 1950’s, many Chinese scientists have explored the remains of the Quaternary glaciation in the Qinghai-Xizang (Tibet) Plateau and its surrounding mountains. In the main, 3–4 glaciations have been recognized. The largest one occurred in the Late Middle Pleistocene with piedmont glaciers, ice caps and trellis valley glaciers in many high peak regions. But here is no evidence of a unified ice sheet covering the whole plateau as described by M. Kuhle. Due to the further uplifting of the Himalayas and Qinghai-Xizang Plateau the climate became progressively driver, diminishing the extension of glaciers during the Late Pleistocene. The elevation of the snow line during the Last Glaciation was about 4,000 m on the south, east and northeast edges of the plateau and ascended to 5500 m on the hinder northwest of the plateau. The thermal effect of the big plateau massif, the sharp increase of aridity from the southeast rim to the northwest inland area and the abrupt decrease of precipitation during the Ice Age largely account for the distribution of the Quaternary glaciers in the Qinghai-Xizang Plateau. The neglect of Chinese literature may be one of the causes accounting for M. Kuhle’s misinterpretation on the environment of the Quaternary glaciations in the Qinghai-Xizang Plateau.  相似文献   

14.
With the methods of regression analysis and trend surface analysis, taking the bottom and top lines of dark conifer forest, bottom line of permafrost and the snowline of the latest glaciation in China as examples, this paper discusses the zonality regulaties of the distribution of physico-geographical zones in China. (1) Latitude zonality obeys the mathematical model of normal frequency distribution, being approximate to descending straightly within the latitude of China. (2) Longitude zonality shows that the elevation of physico-geographical zone rises straightly with the distance to east coast. (3) The combination of latitude and longitude zonalities appears a plane inclining from SSW to NNE. The decline of physico-geographical zone resembles a semiellipse- sphere inclining from the Qinghai-Xizang (Tibet) Plateau to northeast China, reflecting the effect of relief. (5) Physico-geographical zonation depends on the combination of hydrothermal conditions. Thus the factors influencing the distribution reg  相似文献   

15.
The Early Cretaceous flora from the coal-bearing strata(Ussuri and Lipovtsy formations)in the Markovsky peninsula of South Primorye,Far East Russia,is reported in some detail in this paper.The flora containing over 80 species of about 50 genera can be divided into two assemblages.The paleofloristic characteristics and the comparisons of this flora with its coeval floras from the adjacent region of the eastern Heilongjiang of Northeast China,indicate the flora and its coal-bearing strata of the Markovsky peninsula can be compared to those of the Chengzihe and Muling formations of the Jixi area of Heilongjiang,representing probably the late Barremian and Aptian age,respectively.  相似文献   

16.
评估高温灾害的危险性变化,能够为区域高温灾害风险管理和制定减灾措施提供决策依据。本研究选取高温日数、最高温度和平均高温强度3个指标,基于1961—2020年中国2517个气象站点日最高温数据和CMIP6情景模式比较计划中SSP2-4.5情景下12个气候模式提供的2031—2099年未来气候预测数据集,用核密度概率估计方法计算了4个重现期(即5、10、20和50年)下3个指标的取值,对中国未来高温危险性变化进行了评估。结果表明:① 在SSP2.4-5情景下,中国的高温日数呈现出4个危险中心,分别是:西北干旱(半干旱)地区中部、华北和华中地区的交汇区域、西南地区中部和华南地区南部,并且高温日数从这4个中心向外逐渐减少;最高温度在空间上的分布北部大于南部,东部大于西部。平均高温强度的分布则呈现出从华北地区南部、西北干旱(半干旱)地区西部和东部地区西部向我国除青藏高原地区外的其它地区减少的趋势; ② 在SSP2.4-5情景下,随着重现期年限的增长,中国地区3个高温指标均呈增长趋势且增幅较大,并且高值范围也在不断扩大;③ 3个高温指标变化值均呈现出了明显的空间聚集性,3个指标共同显示的热点区域包括西南地区北部和南部、西北干旱(半干旱)地区中部和华北、华中地区的少部分区域,这些地区发生高温灾害的可能最大,同时根据高温日数变化和最高温度变化,东部地区西部发生高温灾害可能也较大,3个指标共同显示的冷点区域包括青藏高原地区东南部、西北干旱(半干旱)地区的西部和我国东南沿海地区,这些地区几乎不会发生高温危险。  相似文献   

17.
Zooplankton was major indicator species of the environment. To explore the effect of marine environment on zooplankton distribution in the coast of China, the zooplankton samples from stations in Guanhe Estuary(GE), Changjiang(Yangtze River) Estuary(CE), Oujiang Estuary(OE), Jiulongjiang Estuary(JE) and Beilun Estuary(BE)(covering 14 latitudes) in spring were surveyed and the variation of zooplankton ecological group was researched. According to the adaptability temperature, the zooplankton was divided into two ecological groups: warm-temperate species and subtropical species. The warm-temperate species was the main dominant species and subtropical species was only dominant species in BE. Calanus sinicus, a warm-temperate species, was the only dominant species in all five estuaries. From north to south, the proportion of warm-temperate species in the five estuaries gradually decreased depends on the number, were 83.33%, 48.39%, 45.00%, 43.75% and 30.43%, respectively. In contrary, the proportion of subtropical species was gradually increased. The warm-temperate species predominated over the total abundance and the percentage was whopping high in the north estuaries, including GE(96.16%), CE(95.57%), OE(97.83%) and JE(95.53%). The abundance percentage of subtropical species have remarkably higher(82.39%) in BE. Five estuaries zooplankton community was subdivided into three zooplankton groups, which were the northern warm temperate zooplankton group, the southern subtropical zooplankton group and the estuarine brackish-water group. The water temperature and coastal current of China Sea are recognized as the main factors determining the distribution and community structure of estuarine zooplankton in spring.  相似文献   

18.
The Quaternary aggradation red earth(QARE) deposit in the middle reaches of the Yangtze River(MRYR) in southern China provides important evidence for understanding the paleoenvironment. However, its provenance remains controversial. In this study, the surface microtextures of grains from the QARE were observed, and compared with those of grains from the loess deposit on the Loess Plateau in northern China. The results show that the surface microtextures and morphologies of the quartz grains in the QARE are distinctly different from those in the northern loess, indicating that the deposits in the two regions have different provenances. The Gobi and deserts in inland northwestern China are not considered as the primary provenance for the QARE in southern China. It is suggested that the large areas of dry and bare river and lake beds and floodplains in the MRYR, which became exposed during glacial periods, provided the dominant source for materials in the QARE. We suggest that against the background of the middle-Pleistocene climate transition(MPT), regional aridification and a strengthened east Asian winter monsoon(driven by global cooling and the rapid uplift of the Tibetan Plateau) were primary drivers for the initiation of the QARE deposit in the MRYR region in southern China. The development of large areas of aeolian red earth deposit is direct evidence of environmental deterioration in the MRYR, indicating a cold and dry environment with frequent aeolian activity, in an area that now experiences a warm and humid subtropical monsoon climate. The results are also evidence of a regional response in the mid-subtropics of southern China to the MPT global cooling event around 1.2 Ma.  相似文献   

19.
Wave simulation was conducted for the period 1976 to 2005 in the South China Sea (SCS) using the wave model, WAVEWATCH-III. Wave characteristics and engineering environment were studied in the region. The wind input data are from the objective reanalysis wind datasets, which assimilate meteorological data from several sources. Comparisons of significant wave heights between simulation and TOPEX/Poseidon altimeter and buoy data show a good agreement in general. By statistical analysis, the wave characteristics, such as significant wave heights, dominant wave directions, and their seasonal variations, were discussed. The largest significant wave heights are found in winter and the smallest in spring. The annual mean dominant wave direction is northeast (NE) along the southwest (SW)-NE axis, east northeast in the northwest (NW) part of SCS, and north northeast in the southeast (SE) part of SCS. The joint distributions of wave heights and wave periods (directions) were studied. The results show a single peak pattern for joint significant wave heights and periods, and a double peak pattern for joint significant wave heights and mean directions. Furthermore, the main wave extreme parameters and directional extreme values, particularly for the 100-year return period, were also investigated. The main extreme values of significant wave heights are larger in the northern part of SCS than in the southern part, with the maximum value occurring to the southeast of Hainan Island. The direction of large directional extreme H s values is focus in E in the northern and middle sea areas of SCS, while the direction of those is focus in N in the southeast sea areas of SCS.  相似文献   

20.
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