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植物和动物的组合的分布构成了大多数生物地理工作的起点,本文将提出对当前研究中四种趋向的一些个人看法,这些研究趋向对回答特有的生物分布如何形成以及为什么形成的问题的不同的解释是有重要意义的。 相似文献
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《中国地理与资源文摘》2007,(1)
P282.12007010907空间斜方位投影研究=The research on the space oblique az-imuth projection/任留成,吕泗洲…∥测绘学报.—2006,35(1).—35~39卫星获取遥感图像的过程是与时间t有关的动态过程,在动态情况下获取的图像数据可以用动态的空间方位投影来描述.研究适合描述这些图像数据的空间斜方位投影,导出卫星星下点轨迹投影公式和空间斜方位投影公式,并研究投影变形情况,最后给出算例.图3表1参10(作者)CheTP39,P512.22007010908基于MATLAB的图解粒度参数计算=A MATLAB methodof graphical calculationfor grainsize parameters/… 相似文献
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马蔼乃 《地理与地理信息科学》2003,19(4):7-11
该文阐述遥感与地理数据编码后的图形与图像在数学上属于同一类问题，其数据编码的一面相当于训练抽象思维的代数学，图形图像的一面相当于训练形象思维的几何学，因此遥感与地理信息相当于训练抽象思维与形象思维结合的解析几何学。人脑的信息处理功能有左右脑皮层的分工与合作，左脑皮层偏重抽象思维，右脑皮层偏重形象思维。当集中某一问题思考时，大脑两半球的神经组成临时网络，以不同的脑波组合(β，α，θ，δ)，从兴奋、沉思、恍然大悟到积极证明的科学用脑过程，是脑能与创造性的源泉。笔者提出遥感与地理信息认知学的目的，是启发认识遥感与地理信息的本质，训练抽象思维与形象思维结合的能力，触发深度知觉，培养坚忍不拔的意志素质，从而达到科学规律发现和技术工具创新的目的。 相似文献
4.
长江源与长江上游环境治理与可持续发展对策 总被引：5，自引：0，他引：5
武素功 《云南地理环境研究》2000,12(2):25-30
长江源及长江上游地区冰川退缩,湖泊干涸,草地沙化,草场退化加速,森林覆盖率锐减,水土流失严重,河流水量减少,泥沙增加,泥石流等自然灾害频繁发生,生物物种减少。日趋恶化的生态环境,已对全流域的社会经济发展构成严重威胁。为治理该地我的生态环境,需建立统一协调机构,制订综合治理规划;充分认识林业的生态功能;尽快建立森林生态经济评估体系和生态效益的补偿制度,保证生态治理资金多渠道和稳定投入;加强科学研究, 相似文献
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中国农业与乡村地理研究进展与展望 总被引：13，自引：2，他引：13
本文回顾了中国农业地理与乡村发展学科的简要发展历程,分析了本学科近年来的研究进展、取得的重要成果及其在区域农业与农村发展决策实践中的应用。通过比较国内外相关领域的研究进展,进一步讨论了适应新时期国家战略需求的中国农业地理与乡村发展创新研究的主要任务和科学命题。中国农业地理与乡村发展学科的最新研究进展归纳为研究成果、新方法与新技术应用、基础研究平台建设与人才培养等方面。其中新近研究成果主要包括：①农业与乡村地理学综合研究;②农村空心化与空心村整治;③新农村建设综合研究;④区域农业与乡村发展研究;⑤研究成果的系统化与国际化。 相似文献
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山洪泥石流风险评估与风险管理理论与方法 总被引：1，自引：1，他引：0
山洪泥石流是中国常见的自然灾害,充分认识其形成机制与潜在风险是防灾减灾的关键。本文阐述了山洪泥石流形成机理,以及风险分析与管理的方法和内容,系统认识了地表产流流量激增、土体破坏物质供给激增、沟道堵塞体级联溃决流量放大和动床侵蚀规模增大等4个山洪泥石流的形成过程,介绍了基于动力过程的山洪泥石流风险评估方法和承灾体易损性评估方法,构建了基于灾害动力过程的风险评估与风险制图方法。进而,基于风险评估结果,提出可用于具体灾害点减灾的风险管理内容和风险调控技术、灾害防治的工程与非工程措施与制技术方案。最后,重点讨论了包括灾害风险预测、临灾预案、灾害防治工程方案等内容的风险处置对策,并形成一套基于山洪泥石流动力过程的风险评估与风险管理理论与方法体系。 相似文献
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环境地理与人类健康研究成果与展望 总被引：5，自引：1，他引：4
中国科学院地理科学与资源研究所倡导和建立了化学地理研究机构,是我国最早从事环境科学研究的单位之一,推动了环境质量调查、环境质量评价、环境背景、环境容量和环境治理等理论和技术的建立和发展;长期进行克山病、大骨节病等地方病的调查及其环境病因与防治的研究,为上述疾病的控制做出了重大贡献;创立和发展了中国的医学地理学研究体系。2000年以后,在持续开展西部地方病地理流行规律和稀土元素生物地球化学循环研究基础上,重点开展了重金属等污染物及全球环境变化的健康风险评价研究,拓展了区域碳、氮、磷等生命元素的生物地球化学循环与温室气体排放的关系研究,强化了环境污染治理和健康保护的技术研究。实现了从化学地理到环境地理、从医学地理到健康地理的转变。未来的环境地理与人类健康研究将以地理环境的化学属性为重点,以人口健康保护为核心,探讨环境保护、社会经济发展和人类健康安全在整体上协调的机制与途径。 相似文献
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中国与伊朗关系研究回顾与展望 总被引：1，自引：1，他引：0
伊朗是中国石油进口的主要来源地之一,也是中国中东战略的重要合作伙伴,中伊关系的发展演变受到广泛关注。本文对改革开放以来国内学者及各界人士对中伊关系研究的文献进行了梳理。从研究内容来看,中伊关系研究的文献主要集中于中伊外交、经贸合作、能源合作、文化交流及农业合作等五方面,尤其以中伊外交和文化交流研究比重最大;其次为中伊贸易合作和能源合作研究,中伊农业合作研究相对较少。而对中伊工业经济、技术合作、跨国投资、国际旅游、劳务输出等诸多领域的研究则鲜有触及。今后国内中伊关系研究应该从两方面继续深化:一是研究视角还需进一步拓宽,尤其是对中观和微观层面上中伊具体合作项目的研究;二是研究的领域还应继续扩大和深化,中伊工业经济、技术合作、跨国投资下的具体合作项目研究应成为关注的重点。 相似文献
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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
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About 70% of its land area as mountains and plateaus, China is the largest mountain country in 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 almost all the temporal zones from tropical rainforest in the southernmost to frigid-temperate needle-leaved
forest in the northernmost; from east to west, it sees a gradual transition fro humid forest landscape to extremely arid desert
landscape; vertical change of landscapes is most striking owing to the existence of many high mountains (above 6000–7000 m,
e.g., the Himalayas, the Kunlun, the Tianshan, the Hengduan, etc.) and plateaus, especially the immense Tibetan Plateau (averagely
4500 m above sea level). All of this give rise to the richness and diversity of ecosystems and landscape in China. Some of
the ecosystems are endemic to China, e.g., alpine desert and alpine steppe in the Tibetan Plateau. As a result, China bears
a great responsibility in the protection of global ecosystems and landscape. 相似文献
13.
NPP vulnerability of the potential vegetation of China to climate change in the past and future 总被引：3，自引：1，他引：2
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
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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
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
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As a typical representative of the herbivorous wild animals in Chang Tang Plateau, the number of Tibetan wild asses has increased significantly in recent years. Clarifying the distribution, population, and size of its habitats is conducive to formulating the protection plan for wild animals and managing the conflict between people and wild animals in Chang Tang Plateau. Based on the distribution probability of Tibetan wild ass habitats and environmental factors, the number of Tibetan wild asses in Gaize County of Chang Tang Plateau was calculated by using the belt transect method and random forest model, and due to the uncertainty of the calculations, the results were corrected and analyzed. The results show that the living environment of Tibetan wild asses in Gaize County of Chang Tang Plateau is at 4400-4600 m above sea level, 350-400 m away from the river, and the average temperature in the warmest season is 10-12 ℃. The vegetation types of habitats are generally temperate tufted dwarf grass, dwarf semi shrub desert grassland, alpine grass, Carex grassland, alpine cushion dwarf semi shrub desert, among others. On the basis of studying the environmental preferences of Tibetan wild asses, the random forest model was corrected by using the data of the second scientific survey sample line of Qinghai-Tibet Plateau for three years. The approximate number of Tibetan wild asses in each of the different areas of Gaize County was obtained. The number of Tibetan wild asses in Gaize Town, Xianqian Township, Gumu Township, Chabu Township, Mami Township, Wuma Township and Dongcuo Township is 855, 3458, 2358, 1453, 743, 943 and 647, respectively. By studying the environmental preferences of Tibetan wild asses and analyzing the results of the belt transect survey, the random forest model can accurately estimate the number of Tibetan wild asses in Gaize County of Chang Tang Plateau. 相似文献
16.
WANG Fang HE Yongtao FU Gang NIU Ben ZHANG Haorui LI Meng WANG Zhipeng WANG Xiangtao ZHANG Xianzhou 《资源与生态学报(英文版)》2020,11(3):290-297
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
17.
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
18.
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
19.
TIAN Li ZHANG Yangjian Claus HOLZAPFEL HUANG Ke CHEN Ning TAO Jian ZHU Juntao 《资源与生态学报(英文版)》2018,9(5):526-537
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
20.
藏北高原高寒草地围栏禁牧和生长季降水对物种丰富度和多样性的影响(英文) 总被引：2，自引：2，他引：0
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