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1.
To protect the richness, diversity and uniqueness of China's ecosystems and landscapes, more than 150 national parks (named "National scenic and historic interest areas" in China), 85 national geoparks and 230 national nature reserves have been delimited nationwide. In addition, a total of 30 world heritage sites (4 mixed, 4 natural, 22 cultural), 24 biosphere reserves and 8 world geoparks have been ratified for China in a short time by the UNESCO. Unfortunately, most of these national and…  相似文献   

2.
About 70% of its land area as mountains and plateaus,China is the largest mountain countryin the world.Thanks to its vast territory (9.6 million km2),outstanding relief and varied climates,China boasts extremely plenty of ecosystems and landscapes.From south to north,it traverses almostall the temporal zones from tropical rainforest in the southernmost to frigid-temperate needle-leavedforest in the northernmost; from east to west,it sees a gradual transition fro humid forest landscape toextremely arid desert landscape; vertical change of landscapes is most striking owing to the existenceof many high mountains (above 6000-7000 m,e.g.,the Himalayas,the Kunlun,the Tianshan,theHengduan,etc.) and plateaus,especially the immense Tibetan Plateau (averagely 4500 m above sealevel).All of this give rise to the richness and diversity of ecosystems and landscape in China.Some ofthe ecosystems are endemic to China,e.g.,alpine desert and alpine steppe in the Tibetan Plateau.As aresult,China bears a great responsibility in the protection of global ecosystems and landscape.  相似文献   

3.
Using the Integrated Biosphere Simulator, a dynamic vegetation model, this study initially simulated the net primary productivity (NPP) dynamics of China’s potential vegetation in the past 55 years (1961–2015) and in the future 35 years (2016–2050). Then, taking the NPP of the potential vegetation in average climate conditions during 1986–2005 as the basis for evaluation, this study examined whether the potential vegetation adapts to climate change or not. Meanwhile, the degree of inadaptability was evaluated. Finally, the NPP vulnerability of the potential vegetation was evaluated by synthesizing the frequency and degrees of inadaptability to climate change. In the past 55 years, the NPP of desert ecosystems in the south of the Tianshan Mountains and grassland ecosystems in the north of China and in western Tibetan Plateau was prone to the effect of climate change. The NPP of most forest ecosystems was not prone to the influence of climate change. The low NPP vulnerability to climate change of the evergreen broad-leaved and coniferous forests was observed. Furthermore, the NPP of the desert ecosystems in the north of the Tianshan Mountains and grassland ecosystems in the central and eastern Tibetan Plateau also had low vulnerability to climate change. In the next 35 years, the NPP vulnerability to climate change would reduce the forest–steppe in the Songliao Plain, the deciduous broad-leaved forests in the warm temperate zone, and the alpine steppe in the central and western Tibetan Plateau. The NPP vulnerability would significantly increase of the temperate desert in the Junggar Basin and the alpine desert in the Kunlun Mountains. The NPP vulnerability of the subtropical evergreen broad-leaved forests would also increase. The area of the regions with increased vulnerability would account for 27.5% of China.  相似文献   

4.
藏野驴作为羌塘高原草食性野生动物的典型代表,近年来数量显著增加。计算羌塘高原野生动物栖息地的分布和种群规模,有利于制定羌塘高原野生动物保护规划,协调人与野生动物之间的矛盾。根据藏野驴栖息地分布的可能性和环境因素,采用样线调查法和随机森林模型计算了羌塘高原改则县的藏野驴数量,并对计算结果的不确定性进行了校正和分析。结果表明,羌塘高原改则县藏野驴适生环境为海拔4400–4600 m,距河流350–400 m,最暖季节的平均温度为10–12℃。栖息地的植被类型一般为温带丛生矮禾草、矮半灌木荒漠草原、高山禾草、苔草草原、高寒垫状矮半灌木荒漠等。利用三年青藏第二次科学考察样线调查的数据,对随机森林模型预测结果进行了校正,得出了改则县各地区藏野驴的规模,改则镇、先遣乡、古姆乡、察布乡、麻米乡、物玛乡和洞措乡的藏野驴数量分别为855、3458、2358、1453、743、943和647头。通过研究藏野驴的环境偏好,结合样线调查结果数据进行分析,随机森林模型可以较为准确估算出羌塘高原改则县的藏野驴规模。  相似文献   

5.
Present granite landform characteristics and distribution are the integrated result of climate, tectonics and lithology. Various types of granite landforms in China signify climate zonality and differential vertical movement of earth surface, while published research results on Chinese granite landforms are very rare, especially in international journals. Based on the process analysis of chemical weathering and physical disintegration, four granite landform regions in China are classified according to the present climate regime. On the Tibetan Plateau, the cold and freezing climate induced periglacial landscapes; the northeast region is characterized by physical disintegration and low round mounds are widespread; in the northwest region controlled by arid climate, wind-carved minor landscapes are extremely prominent. The most spectacular granite landscapes in China are presented in southeast as a result of longtime chemical weathering under humid and warm conditions, as well as the differential uplift after Neogene. Correlating the weathering crust in southern China, Tibetan Plateau and India, a possible unified planation surface in Neogene is proposed. With corestones as indicators of original weathering front, the differential uplift extent of dissected planation surfaces can be estimated. At least three landforms implying uplift can be identified in southeastern China, with elevations of 300–400 m, 2000 m and 3600 m above the sea level respectively.  相似文献   

6.
Present granite landform characteristics and distribution are the integrated result of climate, tectonics and lithology. Various types of granite landforms in China signify climate zonality and differential vertical movement of earth surface, while published research results on Chinese granite landforms are very rare, especially in international journals. Based on the process analysis of chemical weathering and physical disintegration, four granite landform regions in China are classified according to the present climate regime. On the Tibetan Plateau, the cold and freezing climate induced periglacial landscapes; the northeast region is characterized by physical disintegration and low round mounds are widespread; in the northwest region controlled by arid climate, wind-carved minor landscapes are extremely prominent. The most spectacular granite landscapes in China are presented in southeast as a result of longtime chemical weathering under humid and warm conditions, as well as the differential uplift after Neogene. Correlating the weathering crust in southern China, Tibetan Plateau and India, a possible unified planation surface in Neogene is proposed. With corestones as indicators of original weathering front, the differential uplift extent of dissected planation surfaces can be estimated. At least three landforms implying uplift can be identified in southeastern China, with elevations of 300–400 m, 2000 m and 3600 m above the sea level respectively.  相似文献   

7.
高寒草甸土壤有机碳储量及其垂直分布特征   总被引:24,自引:0,他引:24  
青藏高原是全球变化的敏感区。高寒草甸草原是青藏高原上最主要的放牧利用草地资源之一。选择青藏高原东北隅海北站内具有代表性的高寒草甸土壤进行高分辨率采样,测定土壤根系和有机碳含量。研究得出,青藏高原高寒草甸土壤贮存有巨大的根系生物量 (23544.60 kg ha-1~27947 kg ha-1) 和土壤有机碳 (21.52 GtC);自然土壤表层 (0~10 cm) 储存了整个剖面土壤有机碳总量的30%左右。比较发现,高寒草甸土壤的有机碳平均贮存量 (23.17×104 kgCha-1) (0~60 cm) 较相应深度的热带森林土壤、灌丛土壤和草地土壤的有机碳贮存量高约1~5倍多。在全球碳预算研究中,青藏高原高寒草甸土壤有机碳库不可忽视。随着全球变暖,表层土壤有机碳分解释放的CO2将增加。为了减少高寒草甸生态系统的碳排放,应加强高寒草甸土壤地表覆被的保护,合理种植深根系植物。这对减缓全球大气CO2浓度升高的速率以及可持续开发高寒草甸的生态服务功能都具有重要意义。  相似文献   

8.
利用1982-2000年NOAA/AVHRR卫星的NDVI数据(时间分辨率旬,空间分辨率8 km×8 km),结合同时期的气温和降水资料,基于时滞互相关方法和GIS工具,分析了青藏高原植被覆盖对水、热条件年内变化的时滞响应及其空间特征。结果如下:①除高寒荒漠、森林外,青藏高原植被NDVI与同期旬均温和旬降水相关性均呈高度正相关。其中,中等覆盖度的植被受水、热影响表现更为强烈。②青藏高原植被NDVI对气温和降水有滞后效应,且滞后水平存在空间差异,高原北部(柴达木盆地、昆仑山北冀)和高原南部植被对降水、和温度的响应比较迟缓,而高原中、东部地区植被对温度和降水的响应比较敏感。③不同植被类型对水热条件的响应程度也存在差异,由高到低依次是草甸、草原、灌丛、高寒垫状植被、荒漠,最后是森林。  相似文献   

9.
高寒草甸是广布于青藏高原的主要植被类型,它是青藏高原大气与地面之间生物地球化学循环的重要构成部分,在区域碳平衡中起着极为重要的作用。基于对青藏高原主要高寒草甸生态系统类型CO2通量研究方面的综述,系统分析了高寒草甸生态系统CO2通量日、季、年等不同时间尺度的变化特征以及温度、光合有效辐射、降水等主要环境因子对高寒草甸生态系统CO2通量的影响;同时,结合其他地区草地生态系统,就青藏高原三种典型高寒草甸生态系统类型源汇效应和Q10值进行了比较;最后,结合青藏高原高寒草甸生态系统CO2通量研究的现实与需要,提出了当前存在一些不确定性和有待深入研究的问题。  相似文献   

10.
A synthesis of Holocene pollen records from the Tibetan Plateau shows the history of vegetation and climatic changes during the Holocene. Palynological evidences from 24 cores/sections have been compiled and show that the vegetation shifted from subalpine/alpine conifer forest to subalpine/alpine evergreen sclerophyllous forest in the southeastern part of the plateau; from alpine steppe to alpine desert in the central, western and northern part; and from alpine meadow to alpine steppe in the eastern and southern plateau regions during the Holocene. These records show that increases in precipitation began about 9 ka from the southeast, and a wide ranging level of increased humidity developed over the entire of the plateau around 8-7 ka, followed by aridity from 6 ka and a continuous drying over the plateau after 4-3 ka. The changes in Holocene climates of the plateau can be interpreted qualitatively as a response to orbital forcing and its secondary effects on the Indian Monsoon which expanded northwards  相似文献   

11.
2009和2010年夏天沿藏北高原高寒草地样带调查了高寒草地生态系统(高寒草甸、高寒草原和荒漠草原)在围栏禁牧和自由放牧管理下的物种丰富度和多样性(Shannon-Wiener指数,Simpson优势度指数和Pielou均匀度指数)。研究结果显示:自2006年起藏北高原围栏禁牧在植被类型和区域尺度上没有显著改变物种丰富度和多样性。物种丰富度和多样性主要受生长季降水驱动,超过87%的变异可由生长季降水来解释。物种丰富度和多样性在自由放牧和围栏禁牧2类样地对生长季降水的响应方式一致。物种丰富度随降水呈指数型增长关系,多样性指数则呈现正线性关系。研究结果预示藏北高原地区生长季降水的变化对于物种丰富度和多样性管理至关重要,在未来高寒草地保护研究中应予以重视。  相似文献   

12.
青藏高原和阿尔卑斯山山体效应的对比研究   总被引:1,自引:0,他引:1  
索南东主  姚永慧  张百平 《地理研究》2020,39(11):2568-2580
山体效应不仅对气候产生重大影响,也对区域地理生态格局有深远影响,尤其是它对山地垂直带分布和结构类型等的影响已经为地理学家和地植物学家所认识。目前相关研究主要集中在山体效应定量化方面,缺少不同山地山体效应的对比研究,因此对山体效应的区域差异性了解不足。本文选择欧亚大陆上具有明显山体效应的两个山地青藏高原和阿尔卑斯山为研究对象,利用收集到的气象台站观测数据、林线和DEM数据以及基于MODIS地表温度估算的青藏高原和阿尔卑斯山气温数据等,通过对比分析青藏高原与阿尔卑斯山相同海拔高度上的气温以及林线分布高度等来探讨两个山地的山体效应差异性。分析结果表明青藏高原的山体效应比阿尔卑斯山更为强烈,表现为:① 由于山体效应影响,在相同海拔高度上(4500 m),青藏高原内部气温远高于阿尔卑斯山的气温,尤其是在最热月高原内部气温比阿尔卑斯山内部气温高10~15℃,在最冷月高原内部气温比阿尔卑斯山内部气温高5~10℃。② 由于山体效应影响,青藏高原内部林线也远高于阿尔卑斯山内部林线,约高2000~3000 m。本研究将为山体效应的影响因素分析奠定基础,同时对于揭示欧亚大陆山地生态系统格局具有一定的科学意义。  相似文献   

13.
Enclosure is one of the most widely used management tools for degraded alpine grassland on the northern Tibetan Plateau, but the responses of different types of grassland to enclosure may vary, and research on these responses can provide a scientific basis for improving ecological conservation. This study took one site for each of three grassland types (alpine meadow, alpine steppe and alpine desert) on the northern Tibetan Plateau as examples, and explored the effects of enclosure on plant and soil nutrients by comparing differences in plant community biomass, leaf-soil nutrient content and their stoichiometry between samples from inside and outside the fence. The results showed that enclosure can significantly increase all aboveground biomass in these three grassland types, but it only increased the 10-20 cm underground biomass in the alpine desert. Enclosure also significantly increased the leaf nutrient content of the dominant plants and contents of total nitrogen (N), total potassium (K), and organic carbon (C) in 10-20 cm soil in alpine desert, thus changing the stoichiometry between C, N and P (phosphorus). However, enclosure significantly increased only the N content of dominant plant leaves in alpine steppe, while other nutrients and stoichiometries of both plant leaves and soil did not show significant differences in alpine meadow and alpine steppe. These results suggested that enclosure has differential effects on these three types of alpine grasslands on the northern Tibetan Plateau, and the alpine desert showed the most active ecological conservation in the responses of its soil and plant nutrients.  相似文献   

14.
The net accumulation record of ice core is one of the most reliable indicators for reconstructing precipitation changes in high mountains. A 20.12 m ice core was drilled in 2006 from the accumulation zone of Laohugou Glacier No.12 in the northeastern Tibetan Plateau, China. We obtained the precipitation from the ice core net accumulation during 1960-2006, and found out the relationship between Laohugou ice core record and other data from surrounding sites of the northeastern Tibetan Plateau. Results showed that during 1960-2006, the precipitation in the high mountains showed firstly an increasing trend, while during 1980 to 2006 it showed an obvious decreasing trend. Reconstructed precipitation change in the Laohugou glacier basin was consistent with the measured data from the nearby weather stations in the lower mountain of Subei, and the correlation coefficient was 0.619 (P<0.001). However, the precipitation in the high mountain was about 3 times more than that of the lower mountain. The precipitation in Laohugou Glacier No.12 of the western Qilian Mountains corresponded well to the net accumulation of Dunde ice core during the same period, tree-ring reconstructed precipitation, the measured data of multiple meteorological stations in the northeastern Tibetan Plateau, and also the changes of adjacent PDSI drought index. Precipitation changes of the Laohugou glacier basin and other sites of the northeastern Tibetan Plateau had significantly positive correlation with ENSO, which implied that the regional alpine precipitation change was very likely to be influenced by ENSO.  相似文献   

15.
Environmental and Geo-spatial factors have long been considered as crucial determinants of species composition and distributions. However, quantifying the relative contributions of these factors for the alpine ecosystems is lacking. The Tibetan Plateau has a unique ecological environment and vegetation types. Our objectives are to quantify the spatial distributions of plant communities on the Northern Tibetan Alpine grasslands and to explore the relationships between vegetation composition, Geo-spatial factors and environmental factors. We established 63 field plots along a 1200-km gradient on the Northern Tibetan Plateau Alpine Grassland and employed the two-way indicator species analysis (TWINSPAN) and the detrended canonical correspondence analysis (DCCA). Fourteen communities of alpine grassland were identifiable along the transect and consisted of three vegetation types: Alpine meadow, Alpine steppe, and desert steppe. Vegetation composition and spatial distribution appeared to be largely determined by mean annual precipitation and less influenced by temperature. A large fraction (73.5%) of the variation in vegetation distribution was explained by environmental variables along this transect, somewhat less by Geo-spatial factors (56.3%). The environmental and Geo-spatial factors explained 29.6% and 12.3% of the total variation, respectively, while their interaction explained 43.9%. Our findings provide strong empirical evidence for explaining biological and environmental synergetic relationships in Northern Tibet.  相似文献   

16.
Biodiversity and conservation in the Tibetan Plateau   总被引:1,自引:0,他引:1  
The Tibetan Plateau (Qinghai-Xizang Plateau) is a unique biogeographic region in the world, where various landscapes, altitudinal belts, alpine ecosystems, and endangered and endemic species have been developed. A total of 26 altitudinal belts, 28 spectra of altitudinal belts, 12,000 species of vascular plant, 5,000 species of epiphytes, 210 species of mammals, and 532 species of birds have been recorded. The plateau is also one of the centers of species formation and differentiation in the world. To protect the biodiversity of the plateau, about 80 nature reserves have been designated, of which 45 are national or provincial, covering about 22% of the plateau area. Most of the nature reserves are distributed in the southeastern plateau. Recently, the Chinese government has initiated the “Natural Forests Protection Project of China,” mainly in the upper reaches of the Yangtze and Yellow rivers. “No logging” policies have been made and implemented for these areas.  相似文献   

17.
The Tibetan Plateau (TP) plays a unique role in Earth System Sciences. It represents a key area to understand not only basic geodynamic processes linked with the formation and uplift of mountains and plateaus, but also the interaction between plateau uplift and environmental changes. Over the last 50 million years the formation of the TP has considerably influenced the global climate and monsoon system. Moreover, the TP proves to be extremely sensitive to present-day global change phenomena. Based upon the foundation of the new Institute of Tibetan Plateau Research (ITP) by the Chinese Academy of Sciences (CAS) and through the Memorandum signed by the CAS and DFG (Deutschen Forschungsgemeinschaft), both CAS and DFG provide opportunities to intensify TP research and to develop coordinated research programs. “The Tibetan Plateau – Geodynamics and Environmental Evolution” consisting of one big projects funded by CAS and five projects funded by DFG that cover the pre- and early-collision history of the TP, the Palaeogene/Neogene uplift and climatic dynamics as well as the Late Quaternary and recent environmental and climatic changes on the TP. The projects are linked through several levels of interactions.  相似文献   

18.
过去50年气候变化下中国潜在植被NPP的脆弱性评价   总被引:4,自引:1,他引:3  
借助动态植被模型IBIS,首先模拟了过去50年(1961-2010年)气候变化下中国潜在植被NPP的动态变化,然后采用IPCC第五次评估报告选定的标准气候态时段(1986-2005年)平均气候状态作为“标准年气候”,并将该气候条件下的潜在植被NPP作为评价基准。通过与基准进行比较,计算每一年潜在植被NPP的波动情况,进而评价该年的气候条件是否使潜在植被“不适应”以及“不适应”的程度,最后根据过去50年的“不适应”次数和程度综合判断气候变化下潜在植被NPP的脆弱性。评价结果显示:在过去50年的气候变化下,天山以南的暖温带荒漠生态系统、北方温带草原生态系统以及青藏高原西部的高寒草原生态系统更容易受到气候变化的不利影响,NPP呈现出较高的脆弱性;而大部分以森林为主的生态系统则不容易受到气候变化的影响,NPP脆弱性较低,其中以常绿阔叶林和针叶林为主的生态系统NPP脆弱性更低。此外,天山以北的温带荒漠生态系统以及青藏高原中部和东部的高寒草原草甸生态系统NPP也呈现出较低的脆弱性。  相似文献   

19.
Biodiversity and conservation in the Tibetan Plateau   总被引:1,自引:0,他引:1  
The Tibetan Plateau (Qinghai-Xizang Plateau) is a unique biogeographic region in the world, where various landscapes, altitudinal belts, alpine ecosystems, and endangered and endemic species have been developed. A total of 26 altitudinal belts, 28 spectra of altitudinal belts, 12,000 species of vascular plant, 5,000 species of epiphytes, 210 species of mammals, and 532 species of birds have been recorded. The plateau is also one of the centers of species formation and differentiation in the world To protect the biodiversity of the plateau, about 80 nature reserves have been designated, of which 45 are national or provincial, covering about 22% of the plateau area. Most of the nature reserves are distributed in the southeastern plateau. Recently, the Chinese government has initiated the “Natural Forests Protection Project of China,” mainly in the upper reaches of the Yangtze and Yellow rivers. “No logging” policies have been made and implemented for these areas.  相似文献   

20.
中国热带,亚热带西部地区热量带的划分   总被引:3,自引:0,他引:3  
庞庭颐 《地理学报》1996,51(3):224-229
我国热带,亚热带西部地区山多,高原广,垂直地带性的影响,给热量带的划分带来了困难,因为垂直气候都具有在该地区纬向气候带的基础上衍生而生的,因此,亚热带西部地区热量带的划分也应以纬向地带性为主,基带气候为中亚热带的云贵高原和金沙江河谷仍应归属于中亚热带,青藏高原破坏了纬向地带性规律,其东侧应有一条亚热带西界,这一界线应是北、中、南亚热带遇到青藏高原后的中断界线,而不是北、中、南亚热带与青藏高原寒气候  相似文献   

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