首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 221 毫秒
1.
民勤县土地沙化特征研究   总被引:1,自引:0,他引:1  
阐述了民勤县土地沙化与荒漠化的发展历程,指出沙尘暴发生频率与降水多少及新垦地开发关系密切,并预测出今后沙化与沙尘暴的发展和防治土地沙化、荒漠化及沙尘暴发生的措施及建议.  相似文献   

2.
为了研究阿图什市干旱气候的变化和沙尘暴频发的原因,利用阿图什市2005-2007年连续3年的降水量、湿度、PM10浓度、风速、温度与沙尘暴的频发次数相关的气象数据资料,提出改变干旱气候及减少沙尘暴频发的建议,为阿图什市发展生态城市建设提供科学依据。  相似文献   

3.
沙尘暴的基本特征和成因初探   总被引:1,自引:0,他引:1  
从时空分布、气象要素变化等方面介绍了沙尘暴的基本特征,简要叙述了沙尘暴的危害,并从大风、沙尘物质及不稳定空气条件等方面初步分析了沙尘暴的成因,进一步提出了一些治理措施。  相似文献   

4.
沙尘暴对大气背景值的影响及遥感技术应用研究   总被引:3,自引:0,他引:3  
对近十多年来发生在我国西北地区的较大沙尘暴,及其对甘肃大气背景值的影响、沙尘暴降尘的沉降量、区域分布、化学组份、粒度分布,应用则沙尘暴和沙尘暴的危害等内容,进行了为期二年的调查、取样和研究,回答了沙尘暴研究者所关心的一些问题。  相似文献   

5.
沙尘暴是甘肃近年来的主要灾害天气之一.文章主要从空间分布、季节、年际变化上分析了甘肃沙尘暴的发生特征、沙尘暴产生的自然及人为原因,最后就甘肃主要生态系统的环境整治、沙尘暴治理提出了一些新的思路.  相似文献   

6.
沙尘暴是造成金昌市TSP污染的主要原因   总被引:2,自引:0,他引:2  
通过分析金昌市环境空气质量现状,提出了环境空气主要污染物为TSP,阐明了沙尘暴是导致环境空气中TSP污染严重的主要原因,提出了控制沙尘暴的对策及建议。  相似文献   

7.
沙尘暴对金昌市环境空气质量的影响及控制对策   总被引:3,自引:1,他引:3  
通过对金昌市环境空气质量现状的分析,指出了环境空气主要污染物为TSP,阐明了沙尘暴是导致环境空气中TSP污染严重的主要原因,并提出了控制沙尘暴的对策及建议。  相似文献   

8.
沙尘暴路径分析   总被引:4,自引:0,他引:4  
从气象状况、地理条件、沙尘暴路径实际分布等几个方面论述了我省沙尘暴移动的路径。从路径的形成机理谈起:强风、沙源、热不稳定性等因素是沙尘暴路径形成的充分条件,气象状况、地理环境是形成沙尘暴路径的必要条件,通过理论分析得出影响我省的主要沙尘暴路径,勾画出我省沙尘暴的路径并依据事实进一步验证沙尘暴路径。同时对相关的内容进行必要的讨论。  相似文献   

9.
东北亚地区沙尘暴监测合作机制研究   总被引:1,自引:1,他引:0  
近年来,东北亚各国重视沙尘暴问题,开展了沙尘暴监测及研究等合作,逐步建立起东北亚地区沙尘暴监测合作机制.合作机制对推动东北亚地区共同治理沙尘暴问题具有积极意义.文章通过分析东北亚主要国家中国、日本和韩国的沙尘暴监测机制,探讨沙尘暴监测的合作机制模式,进而分析合作机制对推动各国在监测方法、管理机制等方面的促进作用.  相似文献   

10.
一次特大沙尘暴对乌鲁木齐市环境空气质量的影响分析   总被引:7,自引:0,他引:7  
徐鸣  王建国 《干旱环境监测》2002,16(3):139-141,144
通过对2001年5月11日乌鲁木齐市发生的特大沙尘暴及同期有关监测数据进行分析比较,指出乌鲁木齐市沙尘暴中的主要污染物为空气中的可吸入颗粒物,其成因除自然环境因素处,还与城市扬尘有关。  相似文献   

11.
基于颗粒物浓度的沙尘天气分级标准研究   总被引:11,自引:2,他引:11  
沙尘天气在近年对我国城市空气质量造成明显影响。目前我国沙尘天气分级仍然按照气象标准 ,主要是以水平能见度进行分级。文章参考国外的有关标准 ,通过统计近年来我国沙尘天气过程中的颗粒物浓度 ,结合我国沙尘天气的发生情况和特点 ,提出了基于沙尘浓度的沙尘天气分级标准  相似文献   

12.
针对在新疆特殊干旱气候条件下PM10仪器多年来运行中暴露出的问题,研究和探讨PM10自动监测仪在干旱、风沙多发地区数据的适应性和准确性,提出仪器软硬件方面的改进措施以及减少测量误差的方法,为今后研究干旱区城市沙尘污染变化和改进国产自动监测仪器对干旱风沙区的适应性等提供一些参考。  相似文献   

13.
基于2012年11月至12月上午轨道星Terra共7景MODIS数据,对影响青海省的一次典型沙尘事件进行研究。结果表明,沙尘天气始于2012年11月18日,在12月1日及2日达到高峰,持续到12月18日趋于减弱;沙尘天气影响区域范围较广,主要影响省域西北、东北地区,面积占省域面积的11.26%至43.36%;沙尘天气扩散趋势与路径整体上由西北向东北地区,东部人口密集区沙尘天气出现时间相对西北地区、青南高原地区出现滞后。  相似文献   

14.
古尔班通古特沙漠边缘植被破坏严重,沙丘活化明显,是新疆干旱区植被恢复的重点地区之一,一般缺乏地表水补充,其沙丘的水分状况便成为植被生存和恢复过程的关键条件。为掌握古尔班通古特沙漠边缘活化沙丘水分状况,并在其上恢复自然植被,对植物生长期内沙丘水分进行连续监测,并采用当地采集的梭梭、白梭梭种子进行植被恢复实验,结果表明:活化沙丘表层存在干沙层,沙丘中部和下部存在稳定湿沙层,处在距沙丘表面60 cm以下,且厚度超过100 cm,具备植被自然恢复的基础,干沙层的形成速率和风蚀是制约活化沙丘植被自然恢复的决定因素。  相似文献   

15.
内蒙古土地盐渍化典型区域动态监测研究   总被引:4,自引:0,他引:4  
对内蒙古的巴盟河套、中西部草原区和科尔沁沙地土地盐渍化 1 987至 1 997年 1 0年间的动态变化趋势进行监测。结果表明 :巴盟河套地区盐渍化呈上升趋势 ;中西部草原区盐渍化呈下降趋势 ;科尔沁沙地土地盐渍化现象日趋严重。  相似文献   

16.
以1989—2016年玛纳斯河流域TM/OLI遥感影像为数据源,利用混合像元分解技术,计算玛纳斯河流域草地总覆盖度和裸沙面积。在此基础上通过监测年与基期年的比较,计算草地覆盖度相对基期年的减少率和裸沙面积相对基期年的增加率两个监测指标,依据《天然草地退化、沙化、盐渍化的分级指标》(GB 19377—2003),对计算出的两个指标分别进行沙化等级评定和赋值,将两种评定结果相综合来监测草地沙化。结果表明,玛纳斯河流域近30年来荒漠草地沙漠化总体呈现先增加后降低的趋势。分析表明,玛纳斯河流域草地沙化是人为和自然因素双重作用的结果。  相似文献   

17.
The low-rainfall ecologies of the northern fringes of Nigeria are prone to desertification and sand dune activities that are phenomenal and extensive. Stabilization structures put in place by various governmental and non-governmental agencies to check desertification in northwestern Nigeria were evaluated with respect to efficiency, impact on soil development and yield of millet. The study focused on the active and stabilized sand dune formations in NW Nigeria. Various stabilization techniques were identified within Gidan Kaura (the study site) and results were compared with an unstabilized sand dune (control site). Results obtained indicated that the sand dunes within the study area are still active despite the numerous stabilization structures, some of which were established over 15 years ago. Shelterbelts were the most effective techniques in sand dune stabilization and soil development when properly sited across wind direction. Shelterbelts recorded significantly higher levels of pH, organic carbon, total nitrogen, exchangeable bases and micronutrients except for copper, when compared with all other treatments. The least effective of all the structures was mechanical fencing, probably due to the inadequate quantity of plant residues used in its construction. The impact of the various structures on the physical and chemical soil properties was evaluated for surface soils as were the structures on the yield of millet in stabilized dunes and non-dune areas. The results are discussed in depth in this paper.  相似文献   

18.
Hydrostratigraphy and hydrogeology of the Maira vicinity is important for the characterization of aquifer system and developing numerical groundwater flow models to predict the future availability of the water resource. Conventionally, the aquifer parameters are obtained by the analysis of pumping tests data which provide limited spatial information and turn out to be costly and time consuming. Vertical electrical soundings and pump testing of boreholes were conducted to delineate the aquifer system at the western part of the Maira area, Khyber Pakhtun Khwa, Pakistan. Aquifer lithology in the eastern part of the study area is dominated by coarse sand and gravel whereas the western part is characterized by fine sand. An attempt has been made to estimate the hydraulic conductivity of the aquifer system by establishing a relationship between the pumping test results and vertical electrical soundings by using regression technique. The relationship is applied to the area along the resistivity profiles where boreholes are not drilled. Our findings show a good match between pumped hydraulic conductivity and estimated hydraulic conductivity. In case of sparse borehole data, regression technique is useful in estimating hydraulic properties for aquifers with varying lithology.  相似文献   

19.
Monitoring and assessment of the coastal aquifers are becoming a worldwide concern for the need of additional and sustainable water resources to satisfy demographic growth and economic development. A hydrochemical and geoelectrical investigation was conducted in the El-Omayed area in the northwestern coast of Egypt. The aim of the study was to delineate different water-bearing formations, provide a general evaluation of groundwater quality, and identify the recharge sources in aquifers. Thirty-seven water samples were collected and chemically analyzed from the sand dune accumulations and oolitic limestone aquifers. Fifteen profiles of vertical electrical soundings (VESs) were obtained in the oolitic limestone aquifer to examine the variations of subsurface geology and associated groundwater chemistry. The groundwater reserves in the El-Omayed area are mainly contained in sand dune accumulations and oolitic limestone aquifers. The aquifer of sand dune accumulations contains freshwater of low salinity (average total dissolved solids (TDS)?=?974 mg/l). Groundwater of oolitic limestone aquifer is slightly brackish (average TDS?=?1,486 mg/l). Groundwater of these aquifers can be used for irrigation under special management for salinity control, and regular leaching as indicated by electrical conductivity and sodium adsorption ratio. Results of VES interpretation classified the subsurface sequence of oolitic limestone aquifer into four geoelectric zones, with increasing depth, calcareous loam, gypsum, oolitic limestone, and sandy limestone. Oolitic limestone constitutes the main aquifer and has a thickness of 12–32 m.  相似文献   

20.
碳酸盐碳测定在沙尘暴来源地识别中的应用   总被引:7,自引:0,他引:7  
根据中国大气颗粒物特点 ,在国内沙尘暴研究中首次尝试利用碳酸盐碳进行沙尘暴来源地识别。测定了一系列黄沙、大气颗粒物和沙尘暴源区土壤样品。初步了解了上述样品中碳酸盐碳含量情况 ,结合国外研究结果对影响北京的沙尘暴源区进行推测并与其他方法作了比较  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号