新疆博格达山分段及深浅构造转换关系   总被引：15，自引：1，他引：15  

李涛  王宗秀  周高志  柳永清  李寅 《地学前缘》2004,11(3):103-114

研究表明 ,天山及邻区自中生代以来一直处于热衰减状态 ,博格达山新生代再造山具有“冷隆升”性 ,盆山边界断裂多限于上地壳内 ,而非直通中地壳低速体甚至上地幔的“深大断裂”。造山带内的韧性剪切带是在古生代形成的 ,而不是再造山期的断裂 ,它对造山带隆升及盆山耦合无贡献 ,博格达山的隆升为复式背斜构造所支持。博格达山与准东的关系为背斜北翼与盆地平缓基底构成的挠曲构造 ,而不是被深大断裂分隔的断块。博格达山具有独特鲜明的分段性 ,造山带的两个弧形构造与新生代再生前陆盆地构成独特的“斜方对称”分布样式。以板条观点为指导 ,从盆山单元的平面配置关系和深浅构造转换关系入手 ,探讨了博格达山板内造山阶段的几何学和运动学分段性的成因 ,构建了盆山耦合模式  相似文献   

Mountain Protection Forests against Natural Hazards and Risks: New French Developments by Integrating Forests in Risk Zoning   总被引：4，自引：0，他引：4  

Berger  F.  Rey  F. 《Natural Hazards》2004,33(3):395-404

Forests can play a very significant role in protection against natural hazards and risks in mountain lands, especially against erosion and rockfalls. This paper first assesses knowledge concerning the capacity of forests to control natural hazards, with emphasis placed on forest location in catchments or slopes. Zoning aspects are then presented; based on the use of GIS, they allow determining priorities for forestry operations (cuts and biological engineering), in view to setting up an 'optimal management' of mountain forest ecosystems. Finally, an explanation is given of how the results of research are used for the management and planning of mountain ecosystems, illustrated by an example of researcher-practitioner transfer in France. Zoning, prevention, display and regular aspects are developed. On the basis of the experience and knowledge presented here, recommendations are proposed to better take into account the role of mountain forests in the control of natural hazards and risks. It is necessary to have an adapted legislative and economic framework, define priority forest intervention zones and determine an adapted sylviculture.  相似文献   

重庆石碗溪小流域坡度和高程对土地利用及经济发展的影响   总被引：21，自引：3，他引：21  

罗云云  李瑞雪  屈明 《山地学报》2004,22(2):254-258

坡度和高程是土地资源固有的两个重要环境因子,与土地利用关系密切,尤其是在山区,坡度和高程基本上决定了土地利用的方向和方式,从而影响农业和经济的发展。石碗溪小流域面积20.73km2,为丘陵低山区。按坡度和高程对土地利用的影响程度,把坡度和高程各分为3级,即:0°～15°、15°~25°、>25°和500m以下、500~800 m、800m以上。从1:10 000地形圈上提取土地坡度和高程分级图,与土地利用现状图又叠加,获取各坡度、高程级及其土地利用类型和数据。结果表明,土地面积随坡度、海拔级的增加而加大。耕地分布在各个高程级0～15°的缓坡上,800m以上地区面积最大,果园和森林大多分布在800m以上>25°的陡坡地上。通过分析比较小流域各个行政村2002年农业总收入及种植业、林业、牧业收入与坡度和高程的关系,可以看出坡度和高程对经济发展的影响。最后,根据坡度和高程状况,结合小流域社会经济条件,提出几点建议,以其为山区小流域土地可持续利用及经济持续发展提供科学依据。  相似文献   

金沙江流域(云南境内)山地灾害危险性评价   总被引：14，自引：1，他引：14  

唐川 《山地学报》2004,22(4):451-460

云南境内的金沙江流域是斜坡不稳定的敏感区,根据1988-2000年的区域调查和统计,区内发育山地灾害点1697处,其中流域面积大于1km2的泥石流沟808条,体积大于1×104m3的滑坡580处,体积大于1000m3的崩塌309处。用于山地灾害危险性评价的主要敏感因子包括岩土体类型、山坡坡度、降雨、土地利用、地震烈度和人类活动。在对这些因子进行了敏感性评价的基础上,应用GIS对敏感因子集成评价而产生了云南金沙江流域山地灾害危险性评价图。评价结果表明:高危险区面积占全区面积6464km2的8 77%,中危险区占全区总面积的41 51%,低危险区占41 12%,无危险区占8 60%。山地灾害危险性评价图可以帮助规划者或工程师在土地发展规划中选择最佳建设场所,以减轻灾害的影响。  相似文献   

乌拉苔草光合速率日变化及日同化量   总被引：10，自引：0，他引：10  

徐惠风  刘兴土  徐克章 《湿地科学》2004,2(2):128-132

乌拉苔草沼泽是长白山沟谷湿地的重要类型 ,对其光合速率研究的结果表明 ,乌拉苔草光合速率日变化呈单峰曲线 ,最高峰出现在 1 0时 ,最大值是 1 8.0 7μmol(CO2 ) / (m2 ·s) ;与其该群落伴生的修氏苔草光合速率日变化出现“午休”现象。影响光合速率最大的环境因素是光量子通量密度和叶温 ,呈极显著的正相关 ,其他因素亦多呈正相关 ,环境因子综合影响了乌拉苔草的光合日进程。乌拉苔草光合作用的日总同化量为 1 896 0 1 .2 μmol(CO2 ) /m2 ,是光合能力较强的一种沼泽植物  相似文献   

Wood storage in a wide mountain river: case study of the Czarny Dunajec,Polish Carpathians     

Bart&#x;omiej Wyga  Joanna Zawiejska 《地球表面变化过程与地形》2005,30(12):1475-1494

Storage of large woody debris in the wide, mountain, Czarny Dunajec River, southern Poland, was investigated following two floods of June and July 2001 with a seven‐year frequency. Within a reach, to which wood was delivered only by bank erosion and transport from upstream, wood quantities were estimated for eighty‐nine, 100 m long, channel segments grouped into nine sections of similar morphology. Results from regression analysis indicated the quantity of stored wood to be directly related to the length of eroded, wooded banks and river width, and inversely related to unit stream power at the flood peak. The largest quantities of wood (up to 33 t ha^?1) were stored in wide, multi‐thread river sections. Here, the relatively low transporting ability of the river facilitated deposition of transported wood while a considerable length of eroded channel and island banks resulted in a large number of trees delivered from the local riparian forest. In these sections, a few morphological and ecological situations led to the accumulation of especially large quantities of wood within a small river area. Very low amounts of wood were stored in narrow, single‐thread sections of regulated or bedrock channel. High stream power facilitated transport of wood through these sections while the high strength of the banks and low channel sinuosity prevented bank retreat and delivery of trees to the channel. Considerable differences in the character of deposited wood existed between wide, multi‐thread channel sections located at different distances below a narrow, 7 km long, channellized reach of the river. Wood deposited close to the downstream end of the channellized reach was highly disintegrated and structured into jams, whereas further downstream well preserved shrubs and trees prevailed. This apparently reflects differences in the distance of wood transport and shows that in a mountain river wider than the height of trees growing on its banks, wood can be transported long distances along relatively narrow, single‐thread reaches but is preferentially deposited in wide, multi‐thread reaches. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

中国山岳型旅游地旅游环境研究进展综述   总被引：5，自引：2，他引：5  

魏鸿雁  张建春 《云南地理环境研究》2005,17(3):69-73

随着旅游业的发展，山岳型旅游地环境问题已成为国内外旅游研究的重要领域之一，从对国内相关文献的分析来看，可以从旅游对环境的影响、旅游环境质量及其评价、旅游环境管理、旅游的环境效益，以及对旅游环境的保护5个方面来分析和评价中国山岳型旅游地旅游环境研究进展，可以看出，总体来说目前中国对山岳旅游地环境的研究已经相当广泛和细致，但是在对有些领域的研究上，研究内容还不够全面，而在有些领域的研究上，研究方法也有所欠缺，有待进一步改进和加强。  相似文献   

Snow model sensitivity analysis to understand spatial and temporal snow dynamics in a high‐elevation catchment          下载免费PDF全文

Michael Engel  Claudia Notarnicola  Stefano Endrizzi  Giacomo Bertoldi 《水文研究》2017,31(23):4151-4168

In this paper, we addressed a sensitivity analysis of the snow module of the GEOtop2.0 model at point and catchment scale in a small high‐elevation catchment in the Eastern Italian Alps (catchment size: 61 km²). Simulated snow depth and snow water equivalent at the point scale were compared with measured data at four locations from 2009 to 2013. At the catchment scale, simulated snow‐covered area (SCA) was compared with binary snow cover maps derived from moderate‐resolution imaging spectroradiometer (MODIS) and Landsat satellite imagery. Sensitivity analyses were used to assess the effect of different model parameterizations on model performance at both scales and the effect of different thresholds of simulated snow depth on the agreement with MODIS data. Our results at point scale indicated that modifying only the “snow correction factor” resulted in substantial improvements of the snow model and effectively compensated inaccurate winter precipitation by enhancing snow accumulation. SCA inaccuracies at catchment scale during accumulation and melt period were affected little by different snow depth thresholds when using calibrated winter precipitation from point scale. However, inaccuracies were strongly controlled by topographic characteristics and model parameterizations driving snow albedo (“snow ageing coefficient” and “extinction of snow albedo”) during accumulation and melt period. Although highest accuracies (overall accuracy = 1 in 86% of the catchment area) were observed during winter, lower accuracies (overall accuracy < 0.7) occurred during the early accumulation and melt period (in 29% and 23%, respectively), mostly present in areas with grassland and forest, slopes of 20–40°, areas exposed NW or areas with a topographic roughness index of ?0.25 to 0 m. These findings may give recommendations for defining more effective model parameterization strategies and guide future work, in which simulated and MODIS SCA may be combined to generate improved products for SCA monitoring in Alpine catchments.  相似文献   

Unraveling complex hydrogeological processes in Andean basins in south‐central Chile: An integrated assessment to understand hydrological dissimilarity          下载免费PDF全文

Enrique Muñoz  José Luis Arumí  Thorsten Wagener  Ricardo Oyarzún  Victor Parra 《水文研究》2016,30(26):4934-4943

Groundwater storage, drainage, and interbasin water exchange are common hydrological processes but often difficult to quantify due to a lack of local observations. We present a study of three volcanic mountainous watersheds located in south‐central Chile (~36.9 ° S) in the Chillán volcanic complex (Chillán, Renegado, and Diguillín river basins). These are neighboring basins that are similar with respect to the metrics normally available for characterization everywhere (e.g., precipitation, temperature, and land cover). In a hydrological sense, similar (proportional) behavior would be expected if these catchments would be characterized with this general information. However, these watersheds show dissimilar behavior when analyzed in detail. The surface water balance does not fit for any of these watersheds individually; however, the water balance of the whole system can be explained by likely interbasin water exchanges. The Renegado river basin has an average annual runoff per unit of area on the order of 60–65% less than those of the Diguillín and Chillán rivers, which is contradictory to the hydrological similarity among the basins. To understand the main processes that control streamflow generation, two analyses were performed: (a) basin metrics (land cover, geologic, topographic, and climatological maps) and hydro‐meteorological data analyses and (b) a water balance model approach. The analyses contribute to a plausible explanation for the hydrogeological processes in the system. The soils, topography, and geology of the Chillán–Renegado–Diguillín system favor the infiltration and groundwater movements from the Renegado river basin, mainly to the neighboring Diguillín basin. The interbasin water exchanges affect hydrological similarity and explain the differences observed in the hydrological processes of these three apparently similar volcanic basins. The results highlight the complexity of hydrological processes in volcanic mountainous systems and suggest that a simple watershed classification approach based on widely available data is insufficient. Simple local analyses such as specific flow analysis with a review of the geology and morphology can contribute to a better understanding of the hydrology of volcanic mountainous areas.  相似文献   

基于CIPS软件探讨高山地DOM数据的生产方式     

刘涛  王明宇  于洪雨 《测绘与空间地理信息》2016,(4):186-188

在DOM数据生产中,山地、高山地数据一直以来都是重点和难点。本文分析了高山地影像数据的特点,提出一种与山地、高山地数据相适应的处理方式。最后基于CIPS软件,按需求设计对应的软件处理流程,并使用满足实验要求的高山地影像数据,对这种方式加以实现和验证。  相似文献