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1.
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
2.
阿尔卑斯山山体效应及其对林线的影响分析 总被引：1，自引：0，他引：1
阿尔卑斯山是欧亚大陆上著名的山地,对欧洲的地理生态格局具有重要的影响。山体效应产生的原因在于隆起的高原或山地吸收了更多的太阳辐射。因此,论文以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、数字高程数据,以及基于半球视域算法计算得到的太阳辐射数据等,分析阿尔卑斯山气温的空间分布格局以及最热月、最冷月、全年的太阳辐射量,同时以太阳辐射作为山体效应的代用因子,采用逐步回归分析方法构建了阿尔卑斯山林线分布模型,探究该山地的山体效应及其对林线的影响。研究结果表明：① 阿尔卑斯山具有明显的山体效应,山体内部的太阳辐射量远高于山体边缘地区,这也是山体内部气温和林线高度都高于山体边缘地区的主要原因。最热月、最冷月和全年总太阳辐射量在山体内部比边缘地区分别高10~20、20~40和200~400 kWh/m2。② 太阳辐射能更好地定量化山体效应,以太阳辐射为山体效应代用因子建立的林线分布模型具有更高的精度。与基于气温、降水构建的林线分布模型(R2= 0.522)相比,该模型具有更高的模拟精度(R2 = 0.736),同时太阳辐射对林线分布的贡献率最大(1月、7月太阳辐射的贡献率分别为34.75%、27.82%),超过了气温和降水的贡献率(分别为26.24%和11.17%)。 相似文献
3.
中国山区发展研究的态势与主要研究任务 总被引：8，自引：0，他引：8
山区发展问题是一个世界性难题。山区发展滞后是全球普遍的现象。国际上对山区发展研究十分重视,但发达国家与发展中国家因山区发展的水平和方向不同,对其研究的内容也明显差异。我国山区发展既不同于一般发展中国家,也有别于发达国家,正处于受全国工业化、城镇化快速发展冲击的变革期。山区发展在全国总体战略中占有重要地位,但当前是全国区域发展不平衡的主要贡献者,是“三农”问题的集中区和难点区,是全国脱贫的最后攻坚区。国内对山区发展研究虽然已取得巨大进展,但仍不适应新时期对山区发展的需求,加强全国山区发展研究势在必行。当前我国山区发展研究的重点应放在：山区发展战略,建设社会主义新山区,山区工业化,山区农业产业化,山区聚落和山区脱贫等方面上。应以科学发展观统帅山区发展研究,引入现代发展新理念,引进现代科学新理论和新方法,分别在国家层次、区域层次和聚落层次上开展研究；提倡深入山区,深入农村,深入农户；创建山区发展的长期、连续、定点的跟踪调查、监测,构建全国山区发展社会观测网络。 相似文献
4.
Urbanization and depopulation in the Alps 总被引：2，自引：0，他引：2
Demographic developments in the European Alpine region are analyzed over the period 1870-1990. The region is defined as including parts of Germany, France, Italy, Liechtenstein, Austria, Switzerland, and Slovenia. "Studies of growth, stagnation, decline, commune size, and altitude in almost 6,000 communes are presented on three colored maps.... It is apparent that two highly divergent processes are at work and, accordingly, statistical mean values reveal little of importance. Approximately one-half of Alpine Europe is undergoing general economic and demographic growth and has experienced significant increase in population since the end of the agricultural era. This development has taken place primarily in low-lying valleys and basins and in areas bordering the Alps that have good access to transport routes. Tourism is not as widespread as generally assumed and is usually characterized by a punctate pattern. Only in the western part of the Eastern Alps does tourism account for widespread population growth at higher altitudes; elsewhere the Alps have not been affected by modern development and the economy and population are declining, with some areas in danger of becoming completely abandoned. The results challenge the earlier concept of the Alps as a rural region, once populated by peasants, where tourism now plays a major role." (EXCERPT) 相似文献
5.
西南岩溶山地生态环境研究进展与若干问题 总被引：5，自引：0，他引：5
李阳兵 《云南地理环境研究》2006,18(2):61-65
西南岩溶山地是典型的脆弱生态系统，是中国的关键生态区之一，石漠化逐步扩大等生态退化问题严重制约着该区持续发展，生态亟待恢复重建，但岩溶石漠化治理模式实际上受限于岩溶生态基础理论研究的不足。岩溶山地生态重建与可持续发展研究中应进一步加强地质地貌背景生态效应与生态类型划分问题、岩溶生态系统的恢复重建依赖对生态过程研究的突破、土地利用／土地覆盖的定量研究有待加强、治理模式的尺度性与转型研究，阐明岩溶生态系统的运行过程，提出石漠化类型划分和石漠化分级的科学依据。并通过生态系统评价和生态区评价，诊断存在问题，提出生态系统可持续管理的有效途径和方法。 相似文献
6.
山地环境研究发展趋势与前沿领域 总被引：3，自引：2，他引：3
对国内外山地环境研究现状、发展趋势进行了概括性的介绍,并对国外山地环境研究发展特点和国内山地环境研究中存在的问题进行了归纳,对山地环境概念和山地环境系统特点做了阐述。在此基础上,提出今后山地环境研究的前沿领域：①山地表层环境过程及其变化的综合模型研究；②山地环境演化动力学研究；③山地环境脆弱性与山地环境保育研究；④山地环境与全球变化研究。对开展这四个领域研究的必要性和主要内容做了简要的论述。 相似文献
7.
Ian S. Evans 《Geografiska Annaler: Series A, Physical Geography》2006,88(2):115-133
Mass balance of glaciers in mountain areas varies not only with altitude and regional position but also with aspect, gradient, glacier size, glacier type and detailed topographic position. These factors are combined here in models of how glacier altitude varies, tested with data for the Alps edited from the World Glacier Inventory. An overall northward tendency in glacier numbers (toward 005 ± 4°) and lower altitudes (013 ± 5°) is maintained across a range of glacier sizes, types, altitudes and the major divisions of the Alps. Variation with aspect of glacier altitude (and, by implication, of glacier balance) in the Alps is essentially unimodal, and north‐facing glaciers average 220 m lower in middle altitude than south‐facing: 148 m in the Western Alps, 232 m in the West‐central, 252 m in the East‐central, and 268 m in the Eastern Alps. For smaller subdivisions, confidence intervals on estimates are broader and many differences lack statistical significance. Contrasts are greater in the higher massifs, with greater relief, and lower in cloudy, windward areas. There are small windrelated tendencies east of north along the northern and western fringes, but trends across space are weak: position is thus treated by subdivision into districts and groups. Mid‐altitude averages 2891 m overall and varies from 2552 to 3127 m for 27 glacier districts, and from 2124 to 3209 m for 103 glacier groups. Glacier mid‐altitude varies also with glacier form, nourishment, height range and area, which account for over two‐thirds of variance in combined models. 相似文献
8.
西藏山地半淋溶土壤分布与大骨节病关系研究 总被引：6，自引：3，他引：6
通过西藏大骨节病县与非病县山地耕型褐土和灰褐土各土壤亚类的对比分析表明，山地褐土和灰褐土环境是西藏大骨节病主要土壤类型。其中大骨节病县有3.2万公顷耕种褐土，占全部耕种褐土的89.4%，而非病县仅0.4万公顷，占10.6%；同样，近3.9万公顷的耕种灰褐土分布在病县，占全部耕种灰褐土的97.4%，而非病县仅0.1万公顷，占2.6%。相似的半淋溶耕型土壤环境，雅鲁藏布江南岸多为非病区，北岸多为病区，可能与北岸念青唐古拉山和南岸喜马拉雅山的岩性和成土物质来源差异有关。同时土壤水土流失也可能是影响大骨节病分布的重要因素，水土流失严重的地区多为病区，而非病区多分布在地势较平坦的地区。因此系统研究西藏典型大骨节病区的土壤分异及其土壤侵蚀程度的差异对探讨未来西藏大骨节病的分布与流行有重要意义。 相似文献
9.
皖南山区生态经济发展模式与对策 总被引：6，自引：0，他引：6
文章在分析皖南山区存在的主要生态经济问题基础上。提出了适合皖南山区的5种生态经济发展模式；（1）生态农业发展模式；（2）旅－农－工－贸联动发展模式；（3）生态恢复与重建模式；（4）山区综合开发模式；（5）庭院生态经济模式。文章最后对皖南山区发展生态经济，实现生态系统与经济系统的良性循环提出了具体建议。 相似文献
10.
暴雨山洪灾害预警是中小流域山洪灾害防控体系的薄弱环节,也是决定山洪灾害防控成败的关键。论文围绕山洪灾害预警的核心问题,从中国山洪灾害区域差异特征、山洪灾害预警技术方法、山洪灾害概率预警现状3个方面进行了综述。中国山洪灾害分布存在明显的时空差异,因此有必要根据山洪灾害的区域差异发展有针对性的预警方法。以临界雨量为指标的雨量预警是目前中国中小流域暴雨山洪灾害预警的主要技术手段,但常规方法仅给出一个(组)确定的临界雨量阈值,导致预警结果存在突出的不确定性问题。概率预警可以定量评估诸多不确定性,给出山洪灾害概率预警结果,因此具备很好的理论优势与潜在应用价值。论文展望了山洪灾害概率预警未来的研究重点与方向：(1)充分挖掘暴雨洪水样本信息,开展山洪灾害概率预警基础方法与技术集成研究;(2)加强非平稳性条件下的临界雨量阈值估算与山洪灾害概率预警研究;(3)综合考虑预警阈值发生概率及其致灾概率,优化“多级预警、多级响应”技术方法,推进山洪灾害综合预警业务系统建设与应用。 相似文献
11.
Modelling Transient Ground Surface Temperatures of Past Rockfall Events: Towards a Better Understanding of Failure Mechanisms in Changing Periglacial Environments 
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下载免费PDF全文 Rachel Luethi Stephan Gruber Ludovic Ravanel 《Geografiska Annaler: Series A, Physical Geography》2015,97(4):753-767
Despite the rising interest in mountain permafrost due to climatic changes and a noticed increase of registered rockfall events in the European Alps and other mountain ranges, little is known about transient thermal conditions in the detachment areas of rockfalls. Temperature conditions prior to the rockfall events of 144 past events in the European Alps were modelled with a physically based ground temperature model. To minimise the impact that uncertainty has on interpretations, only relative values were used, that is, percentiles obtained from cumulative distribution functions of the modelled ground surface temperatures from the beginning of the meteorological measurement series up to the event dates. Our results suggest that small and mid‐sized rockfalls (volumes up to 100 000 m3) from high elevation occurred mainly during short‐term periods of unusually high temperatures. This was neither found to be a result of the seasonal distribution (most analysed events in higher elevations occurred from July to September) nor of the longer‐term temporal distribution (most analysed events occurred after 2000) only. Plausible explanations are either a destabilisation related to advective thaw or failure due to stress redistribution caused by large temperature variations. Large deep‐seated rock slope failures (≥100 000 m3) in high elevation occurred all year round. 相似文献
12.
MANUELA PELFINI MAURIZIO SANTILLI 《Geografiska Annaler: Series A, Physical Geography》2006,88(3):223-236
ABSTRACT. Mountain landscapes show rapid evolution, especially at high altitudes, in response to current climate changes. In addition, the greater number of routes and trails made available and the increase in tourism have caused some impacts on mountain areas. Gradual soil erosion has been observed along some hiking trails, with the latter tending to deepen, and with stronger erosion where the trail cuts the slope. Where trails cross forested areas, trees can suffer root damage from foot trampling as roots become exposed. A dendrogeomorphological study was conducted on trees along two hiking trails in upper Valtellina (Italian Alps). On the first trail, in Valle dei Forni, European larches and stone pines, mostly with exposed roots, were sampled. A mean erosion rate of 2.7 mm/a, related to deepening of the footpath, was obtained, and various degrees of root growth disturbance along the trail were observed. In particular, the growth of many sampled roots shows an increase in ring width corresponding with the moment when root exposure occurred, followed, after 3–5 years, by rapid growth suppression. The exposure of many roots has taken place since the 1980s. No significant variations in stem growth were observed, even when there were exposed and damaged roots. Along the second trail, in Valle Alpisella, exposed roots of mountain pines were analysed. A mean erosion rate of 3.2–3.7 mm/a, related to the escarpments bordering the footpath, was obtained, while no significant changes were detected in root growth. 相似文献
13.
M. Bernet M. Brandon J. Garver† M. L. Balestieri‡ B. Ventura§ M. Zattin¶ 《Basin Research》2009,21(6):781-798
The European Alps are a mountain belt that is characterized by a series of discrete orogenic events, which have long been recognized. Despite the inherent episodic nature of orogenic evolution, the Alps have been continuously exhumed, mainly by erosion, but also by normal faulting. Since continental collision started in the late Eocene/Early Oligocene evidence for ongoing erosional exhumation has been preserved in synorogenic sediments that accumulated in basins adjacent to the pro- and retro-side of this double-vergent mountain belt. This long-term erosion record can be used to determine exhumation rates. Lag-times calculated from fission-track (FT) ages of detrital zircon from synorogenic sediments are fairly constant for the European Alps since the Oligocene–Late Miocene. Although the fast exhuming areas were unroofed at rates of 0.4–0.7 km Myr−1 , the overall average exhumation rate is between 0.2 and 0.3 km Myr−1 on a regional scale. The detrital and bedrock zircon FT data of the Alps do not detect the increase in erosion rates since the Pliocene over the past ∼5 Myr, as shown elsewhere. This increase cannot be detected yet with the detrital zircon FT method because not enough rock has been removed to widely expose zircons with Pliocene or younger cooling ages in the Alps. Long term (30 Myr) exhumation rates appear to have been approximately constant when averaged over a sliding time window of about 8 Myr, or depth window of 5 to 10 km (ZFT closure depths); shorter-term fluctuations are not identified using this method. 相似文献
14.
山区资源环境承载力研究现状与关键问题 总被引：13，自引：1，他引：12
承载力是度量区域可持续发展的重要参量。本文辨析了资源环境承载力、区域承载力和生态承载力概念的内涵差异,回顾了资源环境承载力的研究历程,探讨了山区资源环境承载力研究中存在的问题。研究认为,目前国内外对山区资源环境综合承载力的研究仍显不足,其系统性有待于深化。主要问题在于:理论体系尚不成熟,仍待继续完善;研究方法和技术手段不足,影响理论发展;多于静态评价分析,少于动态预测研究;山区资源环境承载力研究套用平原研究模式,未充分贴合山区自身特点。基于前瞻性,资源环境承载力研究需要进一步完善理论体系,深入探索其定量研究的技术和方法,充分重视山区资源环境承载力所具有的"国家性"特征,深刻认识山区少数民族文化因素对资源环境承载力的影响,更好地把握山区资源环境承载力的空间分异特征,从而使资源环境承载力研究成果更具有指导性。 相似文献
15.
本试验针对怀化地区山地制度建设问题,通过建立山地档案制度,使山地产权制度、使用权流转制度和山地开发管理制度更趋规范化、科学化,消除由于流转不规范而影响山地开发的隐患,对促进山地的集中,规模开发和利用,提高山地生产力取得了明显的成效。 相似文献
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17.
GIOVANNI LEONELLI MANUELA PELFINI 《Geografiska Annaler: Series A, Physical Geography》2008,90(1):75-86
Climate change and climate anomalies are inducing strong variations in the high‐mountain environment, driving the responses of physical and biological systems differently. This paper assesses tree‐ring growth responses to climate for two Norway spruce (Picea abies (L.) Karst.) sites at different altitudes from an Ortles‐Cevedale Group (OCG; internal zones of the Central Italian Alps) valley site and reports some examples of climate impact on glacier dynamics in the OCG in recent decades. Growth–climate relationships between tree‐ring chronologies and meteorological data were established by means of Pearson's correlation and response functions. In the high‐altitude chronology we found a strong signal of July temperatures, whereas the low‐altitude chronology also contained a signal of summer precipitation. Climate anomalies occurring in these months proved to influence tree growth at the two sites differently. In summer 2003 extreme climatic conditions established over Europe and the Alps, strongly affecting physical and biological systems. Spruce responses to the climate anomaly of 2003 were more evident with a one‐year lag. The high‐altitude site profited from the warmer growing season, whereas trees at the low‐altitude site experienced water stress conditions and their growth was strongly inhibited also in the following year. Glacier mass loss in the OCG in 2003 was the highest since yearly measurement started. The examples reported confirm the strong and even divergent variations affecting the Alpine environment, induced by recent climate change. 相似文献
18.
J?rg L?FFLER 《地理学报》2007,17(1):3-19
The dynamics of water and energy fluxes in the high mountains of central Norway was studied along micro-spatial topographic gradients in different altitudes and regions of the Scandes. Landscape ecological processes like snow accumulation during winter, snow melting, evaporation, percolation, soil moisture variability and temperature variations were quantified. Combining spatio-temporal data on physical environment functioning and vegeta-tion patterns resulted in a process-oriented characterisation of high mountain ecosystems. Extensive data from long-term measurements were synthesised illustrating the influence of micro-climate, snow cover, and soil moisture on high mountain ecosystem functioning. The results reveal that the micro-climatic impact on the vegetation is predominantly determined by snow cover overlaying soil moisture gradients. Water only becomes superior where near-surface water saturation and flooding occur. A lack of soil moisture availability was not found during any time of the year even under driest site conditions. Contrasting literature, the Norwegian mountain vegetation was found to be interpreted by environmental variable con-stellations excluding drought stress. 相似文献
19.
Mountain glaciers have an obvious location advantage and tourist market condition over polar and high latitude glaciers. Due to the enormous economic benefit and heritage value, some mountain glaciers will always receive higher attention from commercial media, government departments and mountain tourists in China and abroad. At present, more than 100 glaciers have been developed successfully as famous tourist destinations all over the world. However, global climate change seriously affects mountain glaciers and its surrounding environment. According to the current accelerated retreat trend, natural and cultural landscapes of some glaciers will be weakened, even disappear in the future. Climate change will also inevitably affect mountain ecosystems, and tourism routes under ice and glacier experience activities in these ecosystems. Simultaneously, the disappearance of mountain glaciers will also lead to a clear reduction of tourism and local economic benefits. Based on these reasons, this paper took Mt. Yulong Snow scenic area as an example and analyzed the retreat trend of a typical glacier. We then put forward some scientific and rational response mechanisms and adaptation models based on climate change in order to help future sustainable development of mountain glacier tourism. 相似文献
20.
Jrg LFFLER 《地理学报(英文版)》2007,17(1):3-19
1 Introduction High mountain landscapes above the tree-line are often regarded as close to nature, although human impact has obviously changed the environment, partly exceeding its carrying capac- ity (L?ffler, 2000). Due to their fragility regarding expe… 相似文献