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Study on Evapotranspiration Regularity of 3 Forages in Eastern Qinghai Province
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作者 朱春来 《Agricultural Science & Technology》 CAS 2009年第4期117-119,124,共4页
The transpiration rate and transpiration quantity'of whole plants and foliages of Bromus innerrnis, Medicago sativa and Agropyron cristatum are measured by using improved quick and continuous weighting after being cu... The transpiration rate and transpiration quantity'of whole plants and foliages of Bromus innerrnis, Medicago sativa and Agropyron cristatum are measured by using improved quick and continuous weighting after being cut off method (QCWC). The results show that transpiration rate of branches and foliages of Agropyron cristatum is highest in 3 forages, Medicago sativa is second and Bromus innermis is lowest. From July to September, the average transpiration quantity of whole plants and foliages of 3 forages is highest in August, September is second and July is lowest. 展开更多
关键词 eastern qinghai Bromus innermis. Medicago sativa Agropyron cristatum EVAPOTRANSPIRATION
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THE CRUSTAL STRUCTURE BENEATH THE EASTERN QINGHAI
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作者 Wang Youxue 1, A. Hirn 2, A.Galve\+2, Jiang Mei 3 2.Laboratoire de Sismologie Experimentale, IPG,Paris,France 3.Chinese Academy of Geosciences,Beijing 100037,China) 《地学前缘》 EI CAS CSCD 2000年第S1期289-289,共1页
A Sino\|French joint wide\|angle seismic reflection survey was conducted in eastern Qinghai Province of P. R. China in 1998. There are several geological units in this region, including Sanjiang Fold belt, Bayan Har f... A Sino\|French joint wide\|angle seismic reflection survey was conducted in eastern Qinghai Province of P. R. China in 1998. There are several geological units in this region, including Sanjiang Fold belt, Bayan Har fold belt, eastern Kunkun fold belt, western Qingling fold belt, Qaidam basin and Qilian fold belt. The seismic data acquired in the seismic experiment provides an abundant information and reveals the detailed crustal velocity structure and differences between all the tectonic units in this region. These results will help us to understand the evolution procedure and mechanism of the formation of Qinghai—Xizang plateau.According to the seismic data, several reflection phases were identified. After the phase correlation, the reflectivity method and Dynamic Ray Tracing were applied simultaneously to model the 1\|D velocity structure for different tectonic units, actually to determine the velocity distribution within the crust. Based on the 1\|D depth\|velocity function, keeping the layer\|velocities fixed and only adjusting the shape of the reflectors to fit the observed data by Dynamic Ray Tracing, the 2\|D crustal velocity structures were established for each tectonic unit. The results show that there are some obvious differences between Sanjiang and Bayan Har. The crust is about 76km thick with an average velocity of 6 33km/s in Sanjiang region, but about 64km with an average velocity of 6 26km/s in Bayan Har. On the other hand, the velocity of lower crust in Sanjian is lower (about 6 65km/s) than in Bayan Har (about 6 90km/s), and the thickness of the lower crust in Sanjiang is much thicker than in Bayan Har. A low velocity layer ( v p=5 80~5 85km/s) exists on both sides of Jinsha fault. These evidences indicate the existence of Jinsha suture. 展开更多
关键词 seismic data MOHO REFLECTIONS CRUST eastern qinghai
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Isotopic characteristics of shoshonitic rocks in eastern Qinghai-Tibet Plateau: Petrogenesis and its tectonic implication 被引量:8
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作者 张玉泉 谢应雯 +6 位作者 李献华 邱华宁 梁华英 李建平 赵振华 邓万明 钟孙霖 《Science China Earth Sciences》 SCIE EI CAS 2001年第1期1-6,共6页
The Cenozoic magmatic rocks of shoshonitic series in the eastern Qinghai-Tibet Plateau include potassic alkaline plutonic rocks, volcanic rocks, lamprophyres and acidic porphyries. Analytical results show that these d... The Cenozoic magmatic rocks of shoshonitic series in the eastern Qinghai-Tibet Plateau include potassic alkaline plutonic rocks, volcanic rocks, lamprophyres and acidic porphyries. Analytical results show that these different lithological rocks are extremely similar in Sr, Nd and Pb isotopic compositions with the range of 0.705 187-0.707 254 for 87Sr/86Sr, 0.512 305-0.512 630 for 143Nd/144Nd, 18.53-18.97 for 206Pb/204Pb, 15.51-15.72 for 207Pb/204Pb and 38.38-39.24 for 208Pb/204Pb. They are isotopically similar to the EMU end-member. This indicates that mantle metasomatism must have taken place in their source region. The formation of these particular rocks is related to crustal thinning and mantle upwelling in a large-scale strike-slip and pull-apart fault zone at about 40 Ma in northern and eastern Qinghai-Tibet Plateau. 展开更多
关键词 isotopic characteristics magmatic rocks shoshonitic series eastern qinghai-Tibet Plateau.
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Temporal and Spatial Variations of ET 0 and Sensitivity Coefficients in Spring-summer in Eastern Agricultural Areas of Qinghai,China 被引量:1
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作者 ZHAO Lu LIANG Chuan +2 位作者 CUI Ningbo WEI Renjuan YANG Haoxiang 《Journal of Mountain Science》 SCIE CSCD 2012年第6期817-826,共10页
Reference crop evapotranspiration(ET 0) is a key parameter to calculate crop water requirements.In the paper,ET 0 during 1960-2005 was calculated with FAO-56 PM in eastern agricultural areas of Qinghai,China.Then the ... Reference crop evapotranspiration(ET 0) is a key parameter to calculate crop water requirements.In the paper,ET 0 during 1960-2005 was calculated with FAO-56 PM in eastern agricultural areas of Qinghai,China.Then the sensitivity coefficients of ET 0 to meteorological variables were estimated through the nondimensional partial derivative in FAO-56 PM.Results show that the mean annual ET 0 of the whole area is 904 mm,and ET 0 portrays a very significant decrease during the 46 years.In spatial,ET 0 decreases from southeast to northwest,firstly increases then decreases from southwest to northeast.Through sensitivity analysis,in spring the most sensitive variable is relative humidity,while in summer is temperature.The temperature,sunshine duration and wind speed sensitivity coefficients(S(TA),S(n),S(u)) are higher in middle areas as opposed to surrounding areas,while the relative humidity sensitivity coefficient(S(RH)) has an opposite distribution rule. 展开更多
关键词 ET0 FAO-56 PM Sensitivity coefficients eastern agricultural areas of qinghai
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Episodes of Cenozoic Gold Mineralization on the Eastern Margin of the Qinghai-Tibet Plateau:40Ar/39Ar Dating and Implication for Geodynamic Events 被引量:5
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作者 WANGDenghong MAOJingwen +4 位作者 YANShenghao YANGJianmin XUJue CHENYuchuan XUEChunji 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第2期233-253,共21页
A lot of new gold deposits have been found on the eastern margin of the Qinghai-Tibet Plateau during the past two decades. Among them, three main types of gold deposits have been recognized, including quartz-vein-type... A lot of new gold deposits have been found on the eastern margin of the Qinghai-Tibet Plateau during the past two decades. Among them, three main types of gold deposits have been recognized, including quartz-vein-type, shear- zone-type and porphyry-type. The former two types of gold deposits are mainly hosted within metamorphic rocks, while the latter is related to Cenozoic magmatism. Although all of these gold deposits are believed to have been formed during the uplift process of the Qinghai-Tibet Plateau in the Cenozoic era (Wang et al., 2002b), precise isotopic age constraints have still been lacking until quite recently. This paper presents new 40Ar/39Ar data of some gold deposits on the eastern margin of the Qinghai-Tibet Plateau, which indicate that gold mineralization in the region occurred in response to the episodic stages of the orogenies. Recently obtained 40Ar/39Ar data on quartz and feldspars from several gold deposits, such as the Sandiao deposit, the Baijintaizi deposit, the Pusagang deposits, provide new constraints on gold mineralization on the eastern margin of the Qinghai-Tibet Plateau. Geochronological studies of gold deposits along the Daduhe River indicate that there are three stages of gold mineralization. The early two stages occurred as early as 65.1 Ma in the Shuibaiyang deposit and 58.95 Ma in the Ruoji deposit, while the latter stage occurred as late as 25.35 Ma in Baijintaizi and 24.70 Ma in Sandiao. Isotopic dating of three plagioclases from the Beiya deposit, Zhifanggou deposit and Luobodi deposit and a K-feldspar from the Jinchangqing deposit in Yunnan Province indicates that these deposits were formed at two stages. The Zhifanggou and Jinchangqing deposits have early stage records as old as 58.82 Ma in Zhifanggou and 55.49 Ma in Jinchangqing, but all of the above four deposits in Yunnan have late stage records of 23.18 Ma in Jinchangqing, 24.54 Ma in Zhifanggou, 24.60 Ma in Luobodi and 24.56 Ma in Hongnitang. The above results suggest that the gold deposits on the eastern margin of the Qinghai-Tibet Plateau were formed concentratedly at two main episodes, i.e. the end of the Paleocene (about 58 Ma) and the boundary between the Paleogene and the Neogene (about 25 Ma). The later episode appears to be looks like more important and was coupled with the Sichuan movement, which was extensively activated at that period. The beginning of the Cenozoic Era (about 65 Ma) might be another episode of gold mineralization, but only one deposit (Shuibaiyang) in this study has been proved to have been be formed at this stage and might be earlier than the initial collision between the Indian Plate and the Eurasia Plate. In view of geology, the above three episodes of gold mineralization are associated with three events of tectonic- magmatism and/or fluid events. Even though the gold deposits (for example, the Shuibaiyang deposit, Ruoji deposit and Pusagang deposit) were formed at different episodes, all of them are genetically related to tectonic movements in large- scale shear zones. It looks like theat tectonic events (including large-scale strike-slip) between Paleogene and Neogene had a wide influence upon gold mineralization, with new deposits formed and old deposits enriched or superimposed to be a higher grade by new stage of mineralization. The above data suggest that gold deposits were not only concentrated in some areas, but also formed mainly at different boundaries of geological times, indicating that there existed some peak stages of gold mineralization (metallogenic episodes), and that the gold deposits were formed mainly by episodic mineralization. 展开更多
关键词 Southwestern China eastern margin of the qinghai-Tibet Plateau gold deposit metallogenic episodes Sichuan Yunnan the Himalayas CENOZOIC
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Analysis of Outdoor Cultivation of Pepino(Solanum muricatum)in Qinghai Province
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作者 Zhichao HOU Lihui WANG +5 位作者 Guangnan ZHANG Cheng SI Xueke TIAN Zhu SUN Dengkui SHAO Shipeng YANG 《Agricultural Biotechnology》 CAS 2023年第3期1-5,22,共6页
[Objectives]This study was conducted to explore the feasibility of planting pepino(Solanum muricatum Ait.)in Qinghai Province,and to understand the cultivation quality and yield in various areas of Qinghai.[Methods]Wi... [Objectives]This study was conducted to explore the feasibility of planting pepino(Solanum muricatum Ait.)in Qinghai Province,and to understand the cultivation quality and yield in various areas of Qinghai.[Methods]With small fruit type of pepino as the material,four areas in eastern Qinghai were selected to determine the agronomic traits,yield and quality indexes of pepino.[Results]Under the same cultivation conditions,there were some differences in the cultivation status of pepino,but overall,pepino fruit had higher quality.Various physiological indexes were correlated with quality and yield.[Conclusions]This study clarified the specific cultivation situation of pepino in Qinghai Province,and evaluated the quality and yield of pepino,providing strong data support for the promotion and planting of pepino in various regions in the future. 展开更多
关键词 PEPINO eastern agricultural area of qinghai Province YIELD Quality
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青藏高原东坡地形对影响云南降水的高原涡的作用机理 被引量:1
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作者 何钰 朱莉 +4 位作者 李国平 谢家旭 马文倩 陶丽 张万诚 《高原气象》 CSCD 北大核心 2024年第1期42-58,共17页
利用常规观测资料、FNL分析资料及经质控后的自动站小时降水数据,诊断分析了青藏高原东坡地形在2017年7月2-3日高原涡影响云南降水过程中的作用,并利用数值模式WRFv4.0对此次过程进行了地形敏感性试验。结果表明:高原涡是此次云南强降... 利用常规观测资料、FNL分析资料及经质控后的自动站小时降水数据,诊断分析了青藏高原东坡地形在2017年7月2-3日高原涡影响云南降水过程中的作用,并利用数值模式WRFv4.0对此次过程进行了地形敏感性试验。结果表明:高原涡是此次云南强降水的重要影响系统;低涡中心及附近区域中高层维持暖心结构,并呈现显著的上升、下沉运动交替的分布;过程累积雨量分布表现为两条明显的与山脉走向平行的西北-东南向雨带,且具有强弱交错的分布特征,强降水集中出现在午后至傍晚及前半夜两个时段内,中心均位于地形边坡,并随着低涡向下游传播;南亚高压、西北辐散气流、西太平洋副热带高压及滇缅高压为低涡的东移发展提供了有利的高空环流场,500 hPa正涡度及700 hPa水汽通量辐合中心对强降水落区具有较好指示意义;低涡降水期间存在β中尺度重力波,波动由青藏高原东坡地形激发,沿着300~200 hPa的气层传播,高空的非地转平衡运动及垂直风切变为重力波的发展及传播提供了有利条件,重力波先于低涡及降水向下游方向移动及发展,波脊处对应上升运动及辐散中心,波槽处对应下沉运动及辐合中心,强降水及波脊均位于低涡西南侧强辐合上升运动区;地形高度降低后,其机械阻挡抬升作用减弱,重力波和高原低涡消失,雨带强度及空间分布特征发生显著改变。高原东坡地形对高原涡的形成和发展,以及高原涡影响下的云南降水具有重要作用。 展开更多
关键词 青藏高原东坡 高原涡 重力波 地形敏感性试验
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MODIS NDVI饱和性对高寒草甸草地生物量遥感估测的影响——以青藏高原东缘为例 被引量:1
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作者 胡仁杰 陈璇黎 +8 位作者 陈金 张世荣 匡依利 于红妍 吉汉忠 赵晓军 宜树华 孟宝平 李猛 《生态学报》 CAS CSCD 北大核心 2024年第14期6357-6372,共16页
自20世纪70年代开始,归一化植被指数(NDVI)在天然草地地上生物量估测研究中得到了广泛应用。然而,NDVI对高密度植被生物量遥感估测存在饱和现象,使草地生物量遥感估测有较大的不确定性。以青藏高原东缘高寒草甸为例,基于比值植被指数(R... 自20世纪70年代开始,归一化植被指数(NDVI)在天然草地地上生物量估测研究中得到了广泛应用。然而,NDVI对高密度植被生物量遥感估测存在饱和现象,使草地生物量遥感估测有较大的不确定性。以青藏高原东缘高寒草甸为例,基于比值植被指数(RVI)探讨了NDVI的饱和性,并评估了NDVI饱和性对高寒草甸地上生物量时空动态变化分析的影响。结果表明:(1)虽然基于中分辨率成像光谱仪(MODIS)NDVI构建的草地地上生物量估测模型精度较基于RVI构建的估测模型高,但模型对高寒草地地上生物量(生物量大于2314.627 kg/hm^(2))灵敏度较RVI估测模型低,即NDVI阈值大于0.73时,估测模型呈现饱和现象(低估了草地地上生物量);(2)结合RVI和NDVI的相关关系,对饱和部分NDVI遥感植被指数进行校正,校正后最优地上生物量遥感估测模型为线性模型(y=5908.5x-2198.9,R=0.6190,RMSE=902.41 kg/hm^(2)),较调整前RMSE降低了11.72 kg/hm^(2);(3)就NDVI饱和性空间分布而言,从全年6月—9月初(全年第161—257天)饱和性呈现先自东南向西北延伸,后自西北向东南消退的变化趋势,平均低估值介于158.45—293.92 kg/hm^(2)之间,最大低估值出现在8月初(全年第225天),超过600 kg/hm^(2);(4)此外,NDVI饱和性对草地地上生物量年际动态变化趋势分析具有较大的影响,去除饱和性影响后草地地上生物量基本不变的区域减小了21.44%,而年际变化小于-10 kg/hm^(2)和大于30 kg/hm^(2)的区域分别增加了8.48%和16.19%。研究探讨了NDVI饱和性对草地地上生物量遥感估测的影响,以期为精确评估高寒草地地上生物量提供理论依据,同时也为高寒草地资源可持续发展提供科学依据。 展开更多
关键词 高寒草甸地上生物量 NDVI饱和性阈值 遥感估测 青藏高原东缘
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青藏高原东构造结林芝地热田浅部典型电性结构及热储关系
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作者 李栋 祝杰 +3 位作者 叶高峰 金胜 董浩 魏文博 《地质论评》 CAS CSCD 北大核心 2024年第2期577-590,共14页
约40 Ma以来,受控于印度板块的俯冲及后期演化,青藏高原喜马拉雅山系东构造结成为了板块活动最强烈的地区之一;由于深部动力学过程中的浅表响应,该地区地热资源极为丰富。笔者等通过对两条音频大地电磁(AMT)测线进行数据处理与分析,查... 约40 Ma以来,受控于印度板块的俯冲及后期演化,青藏高原喜马拉雅山系东构造结成为了板块活动最强烈的地区之一;由于深部动力学过程中的浅表响应,该地区地热资源极为丰富。笔者等通过对两条音频大地电磁(AMT)测线进行数据处理与分析,查明了测点覆盖区域范围内二维电性结构及主要存在的深大断裂。依据电性结构推测研究区地下1 km深度范围内可分为4层,浅部低阻层为松散砂泥卵石层,下伏的中阻为砾卵石层,其下的低阻为砂岩、板岩、页岩强风化层,最底部的中高阻层推测为古元古界林芝岩群真巴岩组以片岩、花岗岩为主的地层。结合以往大地电磁测深及地震研究发现的地下10~20 km存在大规模近东西向展布且向上延伸熔融流变导致的低速高导体,推测可能是该地区深部热源所在。进一步通过对深部及浅部电阻率模型的综合对比研究,基于地热地质背景、电性结构特征,探讨了该地区的深部热源及热储关系。 展开更多
关键词 地热勘探 音频大地电磁测深法 青藏高原东构造结 电性结构 林芝地热田
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青海东部两次区域性大到暴雨的特征分析
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作者 李剑婕 张青梅 +2 位作者 谢天蓉 苏永玲 廖淑君 《青海科技》 2024年第3期120-126,共7页
利用高空探测资料、ERA5再分析资料、卫星和雷达资料对比分析了2022年8月13日(简称“8.13”)和2023年9月6日(简称“9.6”)强降水过程,结果表明:(1)两次过程都是由副高边缘的西南暖湿气流与西风带波动中的冷空气交汇后造成的;存在2条水... 利用高空探测资料、ERA5再分析资料、卫星和雷达资料对比分析了2022年8月13日(简称“8.13”)和2023年9月6日(简称“9.6”)强降水过程,结果表明:(1)两次过程都是由副高边缘的西南暖湿气流与西风带波动中的冷空气交汇后造成的;存在2条水汽输送带,一条是高空槽前水汽带,另一条是副高外围东南气流水汽带;整层都为上升运动;低层受高温高湿气团控制,中高层有干冷空气入侵;降水云系主要为副高外围的切变线云系叠加高空冷槽尾部盾状低云,云顶亮温较低;以低质心暖云降水为主。(2)“8.13”前期高温高湿,存储了更多的不稳定能量,配合有更深厚的湿层和更强的上升运动,降水效率更高。分析结果可为今后类似区域性大到暴雨天气过程预报提供参考依据。 展开更多
关键词 大到暴雨 青海东部 对比分析 温湿特征
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青海东部表层土壤碳库特征研究
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作者 刘庆宇 马瑛 +2 位作者 程莉 田兴元 喻光建 《环境生态学》 2024年第2期16-24,共9页
通过整合青海省东部地区33 092 km^(2)多目标区域地球化学调查和土地质量地球化学调查数据,估算了青海东部地区土壤有机碳、无机碳和全碳的总储量及平均碳密度,并分析了表层土壤碳空间分布特征和不同土壤类型、土地利用及生态系统单位... 通过整合青海省东部地区33 092 km^(2)多目标区域地球化学调查和土地质量地球化学调查数据,估算了青海东部地区土壤有机碳、无机碳和全碳的总储量及平均碳密度,并分析了表层土壤碳空间分布特征和不同土壤类型、土地利用及生态系统单位碳密度变化规律。结果表明:研究区表层土壤(0~20 cm)碳总储量为272.81 Mt,平均碳密度为8 243.85 t/km^(2);不同的土壤类型、土地利用和生态系统均对表层土壤碳密度及分布规律产生影响;与土壤二普数据有机碳储量对比,青海东部地区整体属于碳源区,在过去20多年里青海东部表层土壤共释放约53.21 Mt有机碳。 展开更多
关键词 土壤碳库 土壤碳储量 表层土壤 土壤类型 青海东部
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青藏高原东部大中型兽类多样性及时空分布格局
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作者 李生强 李叶 +4 位作者 向阳 周丽 王红 白玛德西 登沙 《四川林业科技》 2024年第2期48-62,共15页
物种多样性动态变化及种群现状评估对于物种的科学保护至关重要。青藏高原东部属我国西南山地生物多样性热点地区,具有重要科研价值与保护地位。为了有效评估青藏高原东部地区大中型兽类多样性现状与分布格局,以该地区最具代表性的新龙... 物种多样性动态变化及种群现状评估对于物种的科学保护至关重要。青藏高原东部属我国西南山地生物多样性热点地区,具有重要科研价值与保护地位。为了有效评估青藏高原东部地区大中型兽类多样性现状与分布格局,以该地区最具代表性的新龙县为主要研究区域,系统收集了2013年以来该区域已发表的红外相机相关文献和数据资料,并于2019年12月—2020年10月开展了红外相机调查。结果表明,目前新龙县至少分布有5目14科36种野生兽类,包括7种猫科动物以及7种国家Ⅰ级和16种国家Ⅱ级重点保护野生动物,被IUCN红色名录评估为濒危(EN)的有2种、易危(VU)7种、近危(NT)6种。历年监测研究中,食肉目和鲸偶蹄目物种均较为丰富,7种猫科动物在间隔近3个年度仍被记录。豹(Panthera pardus)的相对多度指数(RAI)和网格占有率(GO)位于前10位。7种猫科动物的RAI以及GO的大小关系为:豹>豹猫(Prionailurus bengalensis)>猞猁(Lynx lynx)>雪豹(Panthera uncia)>金猫(Catopuma temminckii)>荒漠猫(Felis bieti)=兔狲(Felis manul)。研究发现不同季节下不同生境和不同海拔段均有多种猫科动物与多种主要猎物分布,除了荒漠猫和兔狲外的5种猫科动物与主要猎物和干扰因子在不同季节下均存在不同程度的重叠关系。结果反映出青藏高原东部新龙县猫科动物整体种群现状良好,食物资源较丰富,整个生态系统呈现出健康的状态,但后续需进一步加强猫科动物主要分布区干扰因子的科学管控。同时还指出了新龙县以猫科动物为代表的珍稀濒危野生动物保护工作面临的困境并提出了后续的保护工作建议,以供参考。 展开更多
关键词 青藏高原东部 新龙县 红外相机技术 大中型兽类 猫科动物 多样性 分布格局
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青藏高原东缘主要次生林物种多样性与功能多样性随海拔梯度的变化
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作者 王飞 白青蒙 +2 位作者 赵阳 杨永红 刘锦乾 《贵州林业科技》 2024年第3期46-52,共7页
通过对青藏高原东缘甘肃南部白龙江主要次生林的研究,对物种多样性指数和功能多样性指数进行单因素方差分析和Pearson相关性分析。结果表明:(1)物种α多样性指数(SW)和优势度指数(SN)呈双峰正相关,随海拔的升高先增大后减小最后增大;丰... 通过对青藏高原东缘甘肃南部白龙江主要次生林的研究,对物种多样性指数和功能多样性指数进行单因素方差分析和Pearson相关性分析。结果表明:(1)物种α多样性指数(SW)和优势度指数(SN)呈双峰正相关,随海拔的升高先增大后减小最后增大;丰富度指数(S)和均匀度指数(R)呈单峰负相关,丰富度指数(S)表现为先增大后减小,均匀度指数(R)表现为先减小后增大;优势度指数(SN)与均匀度、丰富度指数(S)呈显著性正相关(P<0.05)。(2)β多样性指数表现出相邻海拔区间β多样性指数较大的趋势,海拔区间相差越大β指数越小。(3)功能均匀度指数(FE_(ve))和功能分歧度指数(FD_(iv))随着海拔呈多峰变化,表现出随着海拔的升高先减小后增加然后减小,最后升高;功能丰富度指数(FR_(ic))表现为随海拔的升高先增大后减小然后增大。(4)群落中物种α多样性指数和功能多样性指数呈现复杂的相关性,优势度指数(SN)与均匀度指数(FE_(ve))呈显著正相关,优势度指数(SN)与丰富度指数(R)、多样性指数(SW)与功能分歧度指数(FD_(iv))以及功能均匀度指数(FE_(ve))与功能丰富度指数(FR_(ic))呈显著负相关,其他指数之间相关性均不显著。 展开更多
关键词 物种多样性 功能多样性 海拔 次生林 青藏高原东缘
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Discovery of Jinning Cycle Magmatism in Eastern Part of Eastern Kunlun Orogenic Belt and Its Significance 被引量:1
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作者 Zhu Yunhai Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, China Pan Yuanming Department of Geological Sciences, University of Saskatchewan, Saskatoon, Canada Zhang Kexin Faculty of Earth Sciences, China University of G 《Journal of Earth Science》 SCIE CAS CSCD 2000年第3期134-139,共6页
From the isotopic dating study of gneissic granodiorite, the authors discovered magmatism of the Jinning cycle. Intrusive rocks were formed in the Neoproterozoic, whose Pb Pb ages range from (913±4) Ma to (1 01... From the isotopic dating study of gneissic granodiorite, the authors discovered magmatism of the Jinning cycle. Intrusive rocks were formed in the Neoproterozoic, whose Pb Pb ages range from (913±4) Ma to (1 011±4) Ma and U Pb concordia age is (703±15) Ma. The tectonic settings of the rocks are volcanic arc or syn collision. After the formation of the intrusive rocks, these rocks also experienced reconstruction of Caledonian metamorphism. Based on the Ar Ar dating of metamorphic mineral of muscovite, the metamorphic time is determined to range from (386.8±0.8) Ma to (389.44±3.70) Ma. 展开更多
关键词 Jinning cycle MAGMATISM eastern Kunlun orogenic belt qinghai Province.
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TECTONIC FEATURES AND HYDROCARBON POTENTIAL OF THE EASTERN QAIDAM BASIN
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作者 Yang Minghui, Liu Chiyang 《地学前缘》 EI CAS CSCD 2000年第S1期251-252,共2页
Qaidam Basin, situated in the northeastern Qinghai\|Tibet plateau of western China at 35°55′~39°10′N and 90°~98°20′E, is surrounded by thrusts or folded belts. It is adjacent to the Qilian Mou... Qaidam Basin, situated in the northeastern Qinghai\|Tibet plateau of western China at 35°55′~39°10′N and 90°~98°20′E, is surrounded by thrusts or folded belts. It is adjacent to the Qilian Mountains on the north and northeast and to the Kunlun Mountains on the south, and to the Altun Mountains on the northwest. Qaidam plate is attributed to carbonate platform and non\|marine basin. The first stage is plate\|form from Sinian to Triassic, and the second is basin\|form in intraplate during non\|marine depositional period in Mesozoic and Cenozoic. 1 Tectonic feature The main structural elements of the eastern Qaidam basin, which the west border line is Germ and Dunhuang highway, include the Huobuxun depression, the Tin\|Iron Mountains ridge and Delingha depression as the secondary tectonic unit. These depressions extend along the northeastern edge of the Qinghai\|Tibet plateau, and form above a zone of Paleozoic pericraton subsidence at the north edge of the Qaidam plate during intracontinental orogenic phase in the Indosinian. 展开更多
关键词 TECTONIC feature HYDROCARBON potential eastern Qaidam basin NORTHeastern qinghai—Tibet PLATEAU
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青海东部设施蔬菜种植区土壤质量评价
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作者 张洋 张荣 《青海农林科技》 2023年第3期8-14,21,共8页
本文通过主因子分析方法,对青海东部设施蔬菜种植区的土壤质量状况进行了综合分析评价。结果表明:青海东部设施蔬菜种植区38个土壤耕层样点,21.05%(8个)的土壤处于优等级水平,60.53%(23个)的土壤处于良等级水平,18.42%(7个)的土壤处于... 本文通过主因子分析方法,对青海东部设施蔬菜种植区的土壤质量状况进行了综合分析评价。结果表明:青海东部设施蔬菜种植区38个土壤耕层样点,21.05%(8个)的土壤处于优等级水平,60.53%(23个)的土壤处于良等级水平,18.42%(7个)的土壤处于中等级水平,土壤有机质和速效钾是限制该地区土壤质量的主要因子,所以在今后的设施蔬菜生产中应增施有机肥和钾肥,减少磷肥的施用。 展开更多
关键词 青海东部 设施蔬菜 土壤质量评价
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东昆仑三通沟北锰矿床沉积相与沉积环境 被引量:3
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作者 刘永乐 李文 +6 位作者 赵静纯 李有禄 夏有河 张大明 董志国 李文君 张连昌 《古地理学报》 CAS CSCD 北大核心 2023年第3期671-683,共13页
青海省三通沟北锰矿床是近年在东昆仑南部构造带上新发现的沉积型锰矿。初步研究表明,该锰矿赋存于奥陶—志留系纳赤台群硅质岩和细碎屑岩地层中,但目前该矿床研究程度较低,有关锰矿沉积相和沉积环境尚缺乏深入研究。在区域和矿床地质... 青海省三通沟北锰矿床是近年在东昆仑南部构造带上新发现的沉积型锰矿。初步研究表明,该锰矿赋存于奥陶—志留系纳赤台群硅质岩和细碎屑岩地层中,但目前该矿床研究程度较低,有关锰矿沉积相和沉积环境尚缺乏深入研究。在区域和矿床地质考察的基础上,通过典型地质剖面测量、室内镜下薄片鉴定和地球化学分析等研究工作,认为三通沟北锰矿形成于被动大陆边缘环境;矿区Ⅰ-Ⅲ主矿带形成于南部的深水盆地相,其岩性主要为硅质岩、硅质泥岩、碳质泥岩,夹泥质粉砂岩,其上与斜坡相砂岩和陆棚相砂岩—粉砂岩接触;矿区北部的Ⅳ-Ⅴ矿化带分布于陆棚相带中的局限洼地,岩性主要为泥质粉砂岩、硅质泥岩及硅质岩,含锰岩系顶板为陆棚相粉砂岩、细砂岩及碳酸盐相沉积。总体看,三通沟北锰矿形成于海相陆棚洼地和深水盆地的古地理环境。地球化学分析表明,三通沟北锰矿主矿带的形成与盆地相幕式富氧过程关系密切;锰矿的沉淀机制与通过斜坡相的密度流将浅部含氧水体幕式灌入到(近边缘)深水盆地的过程有关。 展开更多
关键词 沉积相 沉积环境 沉积锰矿 纳赤台群 三通沟 东昆仑 青海省
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青藏高原东缘应力场及地下工程灾害风险研究 被引量:2
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作者 李金轩 郭松峰 +5 位作者 祁生文 张亚国 郑博文 唐凤娇 马行东 张世殊 《工程地质学报》 CSCD 北大核心 2023年第3期736-749,共14页
青藏高原东缘广泛发育着深大活动断裂带,强烈控制着高原东缘区域应力场。本文基于收集的178个点位1181组原位应力数据,通过数值模拟反演得出青藏高原东缘活动断裂影响下青藏高原东缘地应力场,结果表明,青藏高原地应力场呈现出明显的非... 青藏高原东缘广泛发育着深大活动断裂带,强烈控制着高原东缘区域应力场。本文基于收集的178个点位1181组原位应力数据,通过数值模拟反演得出青藏高原东缘活动断裂影响下青藏高原东缘地应力场,结果表明,青藏高原地应力场呈现出明显的非均匀性特征,应力量值由西向东逐渐减小。然后,利用ArcGIS分析青藏高原东缘埋深100~2000 m岩爆及大变形趋势,岩爆集中产生于次级板块内部,岩爆范围基本不随深度变化;而大变形产生于次级板块边界,并随深度增加面积逐渐向板块内部扩大;岩爆及大变形风险等级随埋深呈现规律性变化。最后,通过二郎山隧道隧址区以及双江口水电站两个工程实例探讨了本研究在工程建设中对岩爆及大变形趋势预测的适用性,结果表明,本文给出的青藏高原东缘地下工程灾害趋势与基于强度应力比方法获得的岩爆倾向性以及工程实例中岩爆现象基本一致。 展开更多
关键词 青藏高原东缘 地应力 岩爆 大变形 地质工程
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青藏高原东缘地质环境对植被覆盖度的影响研究:以冕宁县为例 被引量:4
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作者 张慈 赵银兵 +3 位作者 欧阳渊 倪忠云 刘洪 李樋 《沉积与特提斯地质》 CAS CSCD 北大核心 2023年第3期604-614,共11页
研究地质环境对植被覆盖度的影响,有利于认识地质本底对生态环境的影响,促进生态保护与修复。本文选择2003-2018年的MODIS归一化植被指数(NDVI)与增强型植被指数(EVI)的多年平均值与年际变化率作为植被覆盖度的静态和动态刻画指标,应用P... 研究地质环境对植被覆盖度的影响,有利于认识地质本底对生态环境的影响,促进生态保护与修复。本文选择2003-2018年的MODIS归一化植被指数(NDVI)与增强型植被指数(EVI)的多年平均值与年际变化率作为植被覆盖度的静态和动态刻画指标,应用Pearson相关性统计揭示地质因素、地形因素、气象因素和人类活动因素对植被指数的静态相关影响,使用地理加权回归模型(GWR)分析影响因子与植被覆盖度在空间尺度的回归关系。研究结果表明:高程、年均气温和年蒸散发在Pearson分析中对NDVI/EVI平均值有较强相关性,而起伏度、年均气温、年蒸散发和地质复杂度等因子对NDVI/EVI年际变化率有较好的解释作用;GWR分析显示,靠近断层的位置有利于植被发育和改善;当地质复杂度处于中等水平时,更易形成中高植被覆盖,同时利于植被覆盖度提高,当地质复杂度过高时植被覆盖度更易出现中低值;海拔较低、地势平坦和阴坡等地形条件利于植被发育和植被覆盖度升高。 展开更多
关键词 地质环境 植被覆盖度 地理加权回归模型 时空效应 青藏高原东缘
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地下水H、O、C同位素揭示的末次冰盛期以来青海东部岩溶发育响应
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作者 李翠明 彭红明 +3 位作者 毛绪美 董亚群 叶建桥 查希茜 《地球与环境》 CAS CSCD 北大核心 2023年第6期583-592,共10页
青海东部岩溶发育在青藏高原持续隆升的高海拔、高寒的构造和气候背景,具有其独特性。岩溶水作为气候记录档案不仅记录了古气候的变化,也对岩溶发育特征及其变化有所反映。本文通过青海东部岩溶水的H、O、C同位素组成,探讨温度和湿度变... 青海东部岩溶发育在青藏高原持续隆升的高海拔、高寒的构造和气候背景,具有其独特性。岩溶水作为气候记录档案不仅记录了古气候的变化,也对岩溶发育特征及其变化有所反映。本文通过青海东部岩溶水的H、O、C同位素组成,探讨温度和湿度变化,揭示气候变化下青海东部岩溶发育的响应。结果表明,青海东部地区岩溶水化学类型以HCO_(3)-Ca和HCO_(3)-Ca·Mg型为主,水化学组分来源于碳酸盐岩的溶解,岩溶水末次冰盛期以来以大气降水补给为主。从末次冰盛期到全新世早期,总体温度较低,降雨量较多,并在青藏高原持续抬升的地史阶段的夷平面塑造下,青海东部地区形成了独有的高寒-高山岩溶地貌。其中,青海湖流域降雨量较少,温度偏高,岩溶发育不强烈。湟水河流域气候变化频繁,总体气温较低,降雨量较多,是岩溶主要发育地区,且岩溶发育良好。在末次冰盛期,青海东部气候寒冷,降雨量偏多,岩溶较为发育;进入全新世冰后期,气温开始回升,降雨量减少,限制了青海东部岩溶发育强度和深度。末次冰盛期是青海东部地区地表岩溶发育主要时期,岩溶发育方式主要以冻融、冰劈作用为主。 展开更多
关键词 地下水 同位素 末次盛冰期 岩溶发育 青海东部
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