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河川径流对降水变化的响应研究——以渭河为例 总被引:5,自引:5,他引:5
根据1956-1995年的实测水文资料(降水和河川径流量资料),采用特征值对比方法,对陕西省境内渭河流域不同时间尺度内降水特征进行分析,并对流域内多年径流变化也做了相应的统计分析,从而揭示河川径流对降水变化的响应关系,并确定出河川径流变化的主要原因。结果表明:(1)流域内降水年内分配极其不均;年际变化剧烈,进入90年代后降水负距平集中出现,20世纪90年代降水较多年均值有较大程度的减少;(2)流域内河川径流与降水之间存在密切的正相关关系,降水量多的年份,河川径流丰富,反之较枯;(3)河川径流积极响应降水的变化,然而河川径流变化幅度却比降水变化幅度大20%,这个偏差主要是由于频繁的人类活动的干扰造成的。 相似文献
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本文在分析我国东部季风区不同自然带年径流与气侯因子关系的基础上,揭示了径流深随纬度和经度变化的规律,并对不同自然带中人类活动对河川径流的干预强度进行了比较,指出半干旱区是人类活动对径流影响最严重的地区,在这里应加强水资源的保护并大力推行各种节水措施。 相似文献
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《干旱区地理》2021,44(3):807-818
冰川覆盖流域的雪冰融水对河川径流有重要的调节作用。气候变化影响雪冰融水过程和数量变化,河川径流过程和径流量相应变化,其程度与流域冰川情况相关。通过利用CMIP5气候模式输出气象数据驱动流域水文模型,模拟研究天山地区3个不同冰川覆盖率河流(库玛拉克河、玛纳斯河、库车河)的径流对气候变化的响应。结果表明:随着未来气温和降水的持续增加,3个流域的雪融水均有增加,冰融水变化受冰川覆盖面积的影响,在各个流域变化不一致。径流变化主要受降水增加和雪冰融水变化的综合影响,在未来情景下各流域径流均有增加,分别增加了5.8%~14.3%(库车河)、2.9%~11.4%(玛纳斯河)、12.9%~47.1%(库玛拉克河),且冰川覆盖率越大的流域,预估径流不确定性变化区间受冰融水影响越大。预估3个流域的径流、雪冰融水年内分布变化表明,各河流的春季融雪时间提前和融雪量增加使得流域春季径流量较历史时期增大;在夏季,受雪冰融水变化的影响库车河、玛纳斯河夏季径流峰值量减小,而库玛拉克河径流峰值量增加,且预估的各流域夏季径流变化不确定性区间明显大于其它季节。 相似文献
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河流健康理论初探 总被引:27,自引:1,他引:26
健康河流是指在相应一定时期其社会功能与自然功能和谐并能够均衡发挥的河流, 其标志是具有良好的水质、水沙流畅的河床与可维系的河流生态系统。河流健康的指示性因子应是能够基本反映河流自然功能的因子, 包括河床形态、水质、河流生态和河川基流, 但因子的种类和数量因河而异, 其量化标准的确定则要充分考虑河流自然功能和社会功能均衡发挥 的需要和河流水情背景条件的变化。河流健康的核心是有相应足够而洁净的河川径流, 因此 保障河流一定的环境流量对维护河流健康十分重要。人类过多抽取河川径流和开发水电、不当地调控洪水和泥沙、过多向河流排污和过多改变关键物种栖息地水流环境的活动, 均会对河流健康造成严重伤害。本文以黄河为例, 对河流健康指标和低限健康指标的确定方法进行了阐述。 相似文献
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滇池不同流域类型降雨径流对河流氮磷入湖总量的影响 总被引:25,自引:5,他引:20
通过对滇池三种不同流域类型的雨季初始期三场降雨径流的汇水河道的入湖口水质和流量监测 ,重点分析了典型城市纳污河流、城乡结合型河道和农业重污染区河道的营养盐携带状况与特征。研究结果表明 :不同流域类型河流的氮磷营养盐入湖总量受降雨过程及特征、流域类型特征、降雨径流流量、径流水营养盐浓度综合控制。城乡结合型河道 (大清河 )有最高的TP、KN (凯氏N)、NH3 N、NO3 N和NO2 N入湖总量 ,三场降雨累积量分别为11374 3、 12 7971 7、 85 36 5 4、 92 3 4和 84 1 2kg ;城市纳污河流 (乌龙河 )有最高的单位面积入湖总量负荷 ,TP、KN、NH3 N和NO2 N分别为 5 35 7、 5 86 0 5、 382 1 9和 2 4 6kg/km2 。 相似文献
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近数十年湘江流域河流水文变化规律 总被引:5,自引:0,他引:5
湘江是长江中游主要支流之一,作者从制约河川水文要素变化的自然环境因素着手,依据湘江流域有代表性水文测站多年实测水文气象资料,较全面地分析了河川径流,水位,暴雨洪水,泥沙。水化学等水文要素的组成,发展与变化规律。 相似文献
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Bue Nielsen Peder Michael Sørensen M.Sc. 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(1):69-73
Nielsen, Bue and Sørensen, Peder Michael: Changes in regional employment in Denmark in the seventies. Geografisk Tidsskrift 84, 69–73. Copenhagen, January 1984. The paper deals with regional development in employment in Denmark in the 1970's. It uses shift-share analysis to isolate elements and activities responsible for the regional dispersion experienced. In that context the paper discusses the interrelationship between manufacturing industries and public services. 相似文献
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Jung Hoon Han 《The Australian geographer》2017,48(2):255-272
This paper takes a new approach to investigating people who age in place. It provides an explanation for why people age in a place that can be useful in government and corporate planning. Our research investigates the principal factors that drive the decision of a rising number of older Australians to age in place. Many older people wish to age in place rather than move in with their children or be institutionalised. They wish to continue to be active in their local communities and maintain their existing social ties. The concept of ageing in place covers two distinct groups: those who are able to stay in their current dwellings and age in home and those who move house but remain in their local community and age in neighbourhood. Age-friendly home modification is a response to ageing in home, whereas the provision of institutional healthcare and the provision of age-suitable housing to facilitate downsizing are associated with ageing in neighbourhood. Using Household, Income and Labour Dynamics in Australia (HILDA) survey data, this research examines the mobility decisions of older Australians and identifies the major determinants of a decision to age in place. This research argues for a better understanding of ageing in place, differentiating between those ageing in home and those ageing in neighbourhood. 相似文献
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The fractal theory put forward by American mathematician B B Mandelbrot (1967) supplies an effective approach to solve complex
problems. The complex problems in geography have become the main positive study field of fractal theory. Based on the works
of China’s geographers and the summarization of contents of fractal theory, the authors comment on the present situation of
its applications to almost every branch of geography and discuss the related problems and the prospects of fractal study in
geography. 相似文献
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福建九龙江口红树林造林遇到的问题 总被引:4,自引:1,他引:4
中国的红树林在过去50年里面积锐减了近70%,恢复和发展红树林迫在眉睫,红树林人工造林是必由之路。福建九龙江口湿地资源丰富,然而在红树林造林上却遇到了一些问题,这些问题阻碍了九龙江口红树林的恢复和发展,应该引起相关部门的关注。 相似文献
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1IntroductionMany natural phenomena such as zigzag coastline, various landforms, turbulent rivers, etc. cannot be described with traditional Euclid geometry, but they are of self-similarities. Fractal geometry takes the complex phenomena as its research objects and has been developed into a specific theory. So it has been praised as natural geometry. What is fractal means "irregular, fractional, fragmental" and its core is self-similarity (Wang and Cao, 1995). To characterize fractals differ… 相似文献
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我国生物地理学研究进展 总被引:6,自引:1,他引:5
生物地理学研究是生物学和地理学交叉非常明显的部门自然地理学学科,它具有很强的基础研究特点,同时研究成果也具有很大的应用潜力。近年来,我国生物地理学基础研究在国家自然科学基金委等部门的支持下,在山地植被与地理环境、干旱半干旱区植被与地理环境、植物区系、植物物候、土壤动物与土壤生态功能、土壤生物结皮等方面开展了全面而深入的研究。同时拓展了传统生物地理学的研究方向,在植物地理学与全球变化、植物地理学与生物多样性保护、植物地理学与生态系统管理等方面也开展了大量研究。尤为可贵的是干旱半干旱区土壤生物结皮研究、典型温带荒漠区原生荒漠植被对水分改变的响应与适应研究取得了令国内外关注的高水平研究成果。 相似文献
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Hosna J. Shewly 《Singapore journal of tropical geography》2017,38(1):108-122
Drawing on conceptualization of statelessness and ethnographic research on crucial insights of rightessness, this paper investigates how the politico‐geographic‐legality constructs statelessness in the enclaves in India and Bangladesh. Following the decolonization process in 1947, both India and Pakistan/Bangladesh inherited more than 200 enclaves, which comprise 80 per cent of the world's enclaves. With improved bilateral relations, India and Bangladesh officially exchanged the enclaves on 1 August 2015, and the enclave dwellers will gradually be granted citizenship rights over the next few years. In this period of transition from statelessness to statehood, this paper can be read as contemporary history. This paper will draw attention to three aspects of statelessness. First, conceptualization of statelessness not only applies to the refugeehood or de‐territorialization of people but also relates to the process of constructing transterritorial stateless people. Second, this paper will discuss the condition of statelessness constructed in a politico‐geographic‐legal trap. And finally, the paper calls for a wider empirical and critical focus on the hidden geographies of de facto statelessness. 相似文献
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Advances in terrestrial system research in China 总被引:1,自引:1,他引:0
Land surface is of spatial-temporal heterogeneity. Terrestrial system (TS) comprehensively studies on land surface and physical regionalization objectively describes geographical zonation of the system. China has a vast area with apparent spatial variations in resources and environmental conditions, which highly influence on socio-economic development. In this paper, progress of the TS studies in China is overviewed and research priorities in the near future are prospected. Since the 1950s, China has paid great attention to the TS study as its socio-economic development, and conducted research on physical geographical regionalization, eco-geographical regionalization and comprehensive regionalization. Along with the deepening of global change research, dynamics of TS have been highly concerned. During the studies, methodology has been developed from qualitative research of integration of experts’ brainpower gradually to quantitative research based on field observation and experiments of the natural processes, including physical, chemical and biological processes, as well as application of information technology and mathematical simulation. In the near future, TS would combine with the ideology, objectives and key researches of Future Earth program, to focus on the mechanism and regional effects of interaction among land surface elements, the response of TS to global change, the quantitative recognition on regional unit boundary, and the application to TS in sustainable socio-economic development. 相似文献