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561.
This paper presents a methodology for developing a landslide hazard zonation map by integration of global positioning system (GPS), geographic information system (GIS), and remote sensing (RS) for Western Himalayan Kaghan Valley of Pakistan. The landslides in the study area have been located and mapped by using GPS. Eleven causative factors such as landuse, elevation, geology, rainfall intensity, slope inclination, soil, slope aspect, distances from main road, distances from secondary roads, and distances from main river and those from trunk streams were analyzed for occurrence of landslides. These factors were used with a modified form of pixel-based information value model to obtain landslide hazard zones. The matrix analysis was performed in remote sensing to produce a landslide hazard zonation map. The causative factors with the highest effect of landslide occurrence were landuse, rainfall intensity, distances from main road, distances from secondary roads, and distances from main river and those from trunk streams. In conclusion, we found that landslide occurrence was only in moderate, high, or very high hazard zones, and no landslides were in low or very low hazard zones showing 100% accuracy of our results. The landslide hazard zonation map showed that the current main road of the valley was in the zones of high or very high hazard. Two new safe road routes were suggested by using the GIS technology.  相似文献   
562.
地理信息系统图例库的研究   总被引:7,自引:1,他引:6  
党安荣  乔彦友 《地理科学》1996,16(4):370-376
图例库是地理信息系统(GIS)的有机组成部分,开发灵活实用的图例库是研制GIS软件的重要内容之一,关系到GIS成果图形表达的科学性。借鉴INTERGRAPH/IGDS的图例库设计思想,引入“符合集合”及“操作函数”的概念,从图例库的基本内涵、实体内容及主要操作等几方面论述了作者对图例库的研究成果。  相似文献   
563.
五台山变质地体的区域变质相带和变质期次   总被引:5,自引:2,他引:5  
党修鹏 《岩石学报》1993,9(1):55-69
  相似文献   
564.
Zhang  Xiliang  Nguyen  Hoang  Choi  Yosoon  Bui  Xuan-Nam  Zhou  Jian 《Natural Resources Research》2021,30(6):4735-4751
Natural Resources Research - Peak particle velocity (PPV) is an important criterion for assessing the risk level of ground vibration induced by mine blasting. Based on this criterion, many efforts...  相似文献   
565.
白涛  麻蓉  马旭  哈燕萍  黄强 《中国沙漠》2018,38(3):645-650
围绕黄河上游沙漠宽谷河段“多大流量能冲动多大含沙量的泥沙”、“不同流量能冲走多少泥沙”两个关键问题,对沙漠宽谷河段的水沙阈值展开深入研究。通过分析各断面历年水量、沙量变化过程,揭示了沙漠宽谷河段各区间河段的冲淤规律,得到不同区间河段、不同含沙量情况下的水沙阈值系列。基于水量平衡原理与输沙量平衡原理,分析各断面冲沙输沙流量、含沙量与输沙量之间的关系,建立场次洪水的河道输沙量计算模型,量化水量与沙量的转化效果。通过实例计算,不考虑沙漠宽谷河段水沙调控时,头道拐站的输沙量为0.124×108 t,沙漠宽谷河段的冲刷量为0.0527×108 t,考虑水沙调控时,输沙量增加近4倍。水沙调控显著改善了沙漠宽谷河道的水沙关系,冲刷了河槽,验证了水沙阈值及输沙量计算的准确性和可靠性。  相似文献   
566.
Globally, adaptation policies and programmes are being formulated to address climate change issues. However, in the agricultural sector, and particularly in least developed countries (LDCs), concerns remain as to whether these policies and programmes are consistent with farmers’ preferences. This study empirically investigates Nepalese farmers’ willingness to support the implementation of adaptation programmes. To this end, we first developed suggested adaptation programmes in accordance with the adaptation measures identified by LDCs in their National Adaptation Programmes of Actions. We then employed a choice experiment framework to estimate farmers’ willingness to pay (WTP) for adaptation benefits. The findings indicate that the substantial benefits of the adaptation programmes for farmers result in a sizeable WTP to participate, which would appear to justify the programmes’ widespread implementation.

Key policy insights

  • Farmers are willing to participate in, and contribute to, the suggested adaptation programmes in the form of increased access to climate adaptive crop species and varieties, improved soil quality and irrigation and the provision of training in climate adaptive farming.

  • Key socio-economic factors influence farmers’ support of adaptation programmes. Older farmers, those households closer to government extension services, larger land holders, those involved in household labour exchange, farmers located in drought and flood-prone regions and those who perceive that the climate has changed are more likely to participate.

  • The more farmers are aware of climate change impacts, the greater their preference for adaptation programmes. Increasing farmer awareness prior to implementation of such programmes is therefore an obvious means of further raising participation rates.

  相似文献   
567.
Hu  Yijia  Zhong  Zhong  Zhu  Yimin  Ha  Yao 《Theoretical and Applied Climatology》2018,132(1-2):479-489
Theoretical and Applied Climatology - In this paper, a statistical forecast model using the time-scale decomposition method is established to do the seasonal prediction of the rainfall during flood...  相似文献   
568.
This study illustrates the characteristics of the data assimilation system at the Korea Institute of Atmospheric Prediction Systems (KIAPS), based on the cubed-sphere grid system. The most interesting feature is the use of spherical harmonic functions defined on cubed-sphere grid points, which makes it possible to control the allowable physical wavenumber for the analysis increments. The relevant computational costs and parallel scalability are represented. The multiple-resolution approach is a distinguishable aspect of this data assimilation system. The wavenumber, up to which the analysis is conducted, increases as the outer iteration progresses. This multiresolution strategy is based on an investigation into the change of spectral components of analysis increments. The multi-resolution outer-loop provides cost-effective analysis-improvement, by explicitly controlling the analysis increments entered into the observation operator. To utilize the high-resolution deterministic forecast as a background state, it is subtracted from the forecast ensemble, to produce ensemble forecast perturbation that is hybridized with static background error covariance. Based on the cycled analysis experiments, the higher-resolution deterministic forecast is shown to preserve the high-frequency feature of the analysis increment relative to the ensemble mean forecast.  相似文献   
569.
本文以土地变更调查在线核查工作的网络传输安全问题为例,探讨“互联网+”背景下动态网络安全防御策略.以动态网络安全防御机制构建为导向,建立基于可信第三方加密模块的在线传输模型,研究在线核查的网络传输数据加解密方式和用户合法性检验模式;通过图、证分离存储传输策略的制定,实现了一种在线核查数据内容安全的保障方法.  相似文献   
570.
高强度人类活动影响下永定河北京段水质水量模拟   总被引:1,自引:0,他引:1       下载免费PDF全文
自然条件下的河流水质模型在高强度人类活动影响的城市河流应用中存在局限性,构建耦合人类活动影响的水质模型是识别城市河流水质变化的关键。针对永定河北京段自然水循环与再生水、循环管线回水及外调水等人类活动相互作用的特点,构建了基于分布式时变增益水文模型与一维稳态的水质过程耦合的模型,分析了不同调水情景下永定河北京段水质变化过程。应用表明该模型在永定河北京段具有良好的适用性,不仅能描述过去天然条件、现状条件下水质过程,同时能应用于未来规划情景下的水质预测,同时表明外调水工程对永定河北京段的水量水质有显著的改善作用。  相似文献   
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