【摘 要】
:
In many arid and semiarid regions,saline playas represent a significant source of unconsolidated sediments available for aeolian transport,and severe saline dus
【机 构】
:
Xinjiang Institute of Ecology and Geography,Graduate University of Chinese Academy of Sciences
【基金项目】
:
国家重点基础研究发展规划(973计划);国家自然科学基金;the Xinjiang Natural Science Foundation of China
论文部分内容阅读
In many arid and semiarid regions,saline playas represent a significant source of unconsolidated sediments available for aeolian transport,and severe saline dust storms occur frequently due to human disturbance.In this study,saline dust storms are reviewed systematically from the aspects of concept,general characteristics,conditions of occurrence,distribution and ecological impact.Our researches showed that saline dust storms are a kind of chemical dust storm originating in dry lake beds in arid and semiarid regions;large areas of unconsolidated saline playa sediments and frequent strong winds are the basic factors to saline dust storm occurrence;there are differentiation characteristics in deposition flux and chemical composition with wind-blown distance during saline dust storm diffusion;and saline dust storm diffusion to some extent increases glacier melt and results in soil salinization in arid regions.An understanding of saline dust storms is important to guide disaster prevention and ecological rehabilitation.
其他文献
音乐是健美操的"灵魂",它在健美操教学中作用非常突出.本文试从音乐对健美操教学效果的影响,对学生情感和情操的培养,对学生的生理和心理的影响等几个方面进行分析,探讨音乐
Records of the May 12,2008 Ms8.0 Wenchuan,Sichuan,earthquake from 27 stations of Shaanxi Digital Strong Motion Network are processed and analyzed,including base
介绍了某多跨混凝土连续梁桥的整体转动提升技术和监控方法 ,并结合实际效果 ,对类似工程的施工和控制提出建议
This paper introduces the overall rotary lifting technol
介绍了一种使用计算机视觉技术进行苹果外形识别的方法 ,用傅立叶描述子提取苹果的形状特征 ,设计 3层前向神经网络形状进行识别 ,使用遗传算法和BP算法相结合的混合算法进行神经网络权矢量和神经元阈值的学习。试验结果表明该方法具有 80 %以上的正确率。
在宁波地区进行了较大范围的公路桥头跳车现象的调查 ,在此基础上 ,研究桥头引道段不均匀沉降的最大相对沉降量、纵向沉降曲线、纵坡相对差、横坡相对差的统计规律和相互关系
本文在对历年影响海门的台风气候特征分析基础上,总结了台风路径的预报着眼点,提出了台风灾害的防御对策,对提高影响海门的台风预报准确率和防灾减灾能力能起到一定的作用.
The common problem of cold strip continuous annealing furnaces is high exhaust gas temperature and great energy consumption.Taking the cold-strip continuous ann
随着计算机技术和测量仪器的高速发展,数字化测量技术得到快速的发展,本文探讨了数字测绘技术的优点以及几种方法。
对六矿三水平辅助回风巷中水平误差和高程误差计算,所得的实际测量相对闭合差与《测量规程》中规定的相对闭合差进行比较,得出:贯通测量误差预计中,采用实际测量数据比用规程数据进行贯通测量误差预计更能提高测量误差预计精度。
The paper proposes a new method of "Separated Same Rectangle Feature(SSRF)" for face detection.Generally,Haar-like feature is used to make an Adaboost training algorithm with strong classifier.Haar-li