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1.
库布齐沙漠穿沙公路两侧现有工程防沙体系破损情况日趋严重。调查显示,工程防沙体系破损的主要形式是风蚀、沙埋和材料的腐烂,体系破损具有不等时性、不等量性、不均匀性和效益的残留性。在此基础上,制定了防沙体系风蚀、沙埋破损程度的鉴别标准,并针对体系不同的破损形式、原因、程度提出了相应的维护技术,供公路养护部门参考。  相似文献   

2.
内蒙古杭锦旗穿沙公路沿线水资源合理开发利用   总被引:3,自引:0,他引:3  
内蒙古杭锦旗“穿沙公路”,穿越库布齐沙漠 ,沿线防沙治沙工程及生态工程的建设 ,均与水资源的合理开发利用有密切关系。本文根据已有资料和野外调查结果 ,对公路沿线水资源的基本特征进行了分析 ,提出了水资源合理开发利用的措施和建议 ,可为实践工作所参考。  相似文献   

3.
浑善达克沙地公路综合防护技术及其效益分析   总被引:5,自引:0,他引:5  
浑善达克沙地省际通道综合防护体系包括:公路沙害快速治理和沙源控制技术及耐风沙植被建植技术。阻沙带、固沙带改变了风沙流结构,降低了输沙强度,增加了地表粗糙度,有效的起到了削弱风速,阻截流沙,控制沙丘前移,保持地表稳定的作用;建立稳定的耐风沙植被是持久固沙和生物防护的核心;首次大规模使用“固沙网”专利技术产品用于公路快速固沙保苗,实践证明采用固沙网与柳条立式沙障的组合固沙技术对于快速固沙和植被恢复的作用更加显著;并提出了公路沙害快速治理技术体系与配套的技术措施。项目实施过程中3年投入产出比为1∶2.6,通过公路沙害治理工程的实施,稳定防护10年的经济总收益为4.67亿元;如将挖方路堑段砂质陡坡用植物固沙措施代替传统石砌护面墙技术推广至其它工程,效益更为显著。该项目技术研究与工程建设紧密结合,操作性强,能快速有效治理荒漠化地区公路沙害,总结出了沙区公路、铁路沙害的治理模式,对于我国荒漠化治理有推广应用价值。  相似文献   

4.
大沙冬青组织培养的探讨   总被引:8,自引:0,他引:8  
沙冬青(AmmoPiP tanthus C heng f)属豆科,系亚洲中部荒漠特有常绿灌木,在我国有两种,均为国家珍稀濒危保护植物。其中,矮沙冬青在我国仅分布在新疆西南部乌恰县山地;大沙冬青则为阿拉善荒漠特有种,由内蒙西部库布齐沙带至甘肃境内中条山均有分布。沙冬青(A.·mogolicus),又名大沙冬青、蒙古黄花木、蒙古沙冬青,为我国三级渐  相似文献   

5.
绿洲边缘积沙带的研究是一个新的科学问题。甘肃河西地区经过半个多世纪的防沙治沙,在绿洲边缘形成了一条积沙带。为了研究积沙带的形成和发育与气候环境因子之间的关系,对河西走廊东端至走廊中西部绿洲边缘的积沙带进行了调查。结果表明:① 年降水量是决定积沙带高度和宽度的关键因子;② 降水量是决定植被盖度的关键因子,降水对天然植被盖度的影响大于对包括人工植被在内的植被总盖度的影响,随着降水增加,背风坡植被盖度增加幅度大于迎风坡;③ 积沙带不同样点之间植被盖度的差异主要是由植株个体大小引起的,亦即降水对植株个体大小的影响大于对植株密度的影响。  相似文献   

6.
为了研究温带固定半固定沙漠土壤化学性质与地表植被的关系,本文以古尔班通古特沙漠西南缘莫索湾地区沙漠–绿洲过渡带为研究区,分别选取植被覆盖度为10%和15%的半固定沙垄及植被盖度为30%的固定沙垄。采集了各沙垄不同地貌部位的土壤样品,室内测试了土壤pH、电导率、有机质、全氮和全磷等指标。结果表明:① 随着植被覆盖度下降,沙垄西坡、坡顶和东坡,土壤pH、电导率、有机质、全氮和全磷呈逐渐降低趋势;② 不同地貌部位的分布格局各沙垄表现不一致,沙垄A和沙垄B的 pH、电导率、有机质、全氮和全磷含量最大值均出现在垄间地,其他部位之间没有明显的规律,沙垄C 的pH和电导率最大值出现在垄间地,而土壤养分含量于坡顶部位富集;③ 各沙垄不同土层土壤性质分布规律相对一致,土壤pH、电导率随着土层深度的增加呈上升的趋势,而土壤养分随着土层深度的增加而降低;④ 土壤化学性质空间分布异质性与植被的分布格局密切相关,相互影响,当植被覆盖度较高时,生物作用起主导作用,当植被覆盖度较低时,风蚀、地形等非生物因素作用加强,影响生物作用,植被对土壤颗粒和养分的拦截及富集作用逐渐减弱或消失。  相似文献   

7.
从沙物质粒度分析结果研讨沙生植物的固沙作用   总被引:1,自引:1,他引:0  
在库布齐沙漠西部地区固定半固定沙丘柽柳、梭梭、白刺、油蒿、花棒等沙生植物生长区,通过对表面干沙和深层湿沙的沙粒粒径进行对比分析,获得以下数据:表面干沙和深层湿沙极粗沙、粗沙、中沙、细沙、极细沙、粉沙的含量分别为0.14%、0.10%、0.24%、72.90%、24.12%、1.85%;0.04%、0.05%、0.27%...  相似文献   

8.
为了研究温带固定半固定沙漠土壤化学性质与地表植被的关系,本文以古尔班通古特沙漠西南缘莫索湾地区沙漠-绿洲过渡带为研究区,分别选取植被覆盖度为10%和15%的半固定沙垄及植被覆盖度为30%的固定沙垄。采集了各沙垄不同地貌部位的土壤样品,室内测试了土壤pH、电导率、有机质、全氮和全磷等指标。结果表明:①随着植被覆盖度下降,沙垄西坡、坡顶和东坡,土壤pH、电导率、有机质、全氮和全磷呈逐渐降低趋势;②不同地貌部位的分布格局各沙垄表现不一致,沙垄A和沙垄B的pH、电导率、有机质、全氮和全磷含量最大值均出现在垄间地,其他部位之间没有明显的规律,沙垄C的pH和电导率最大值出现在垄间地,而土壤养分含量在坡顶部位富集;③各沙垄不同土层土壤性质分布规律相对一致,土壤pH、电导率随着土层深度的增加呈上升的趋势,而土壤养分随着土层深度的增加而降低;④土壤化学性质空间分布异质性与植被的分布格局密切相关,相互影响,当植被覆盖度较高时,生物作用起主导作用,当植被覆盖度较低时,风蚀、地形等非生物因素作用加强,影响生物作用,植被对土壤颗粒和养分的拦截及富集作用逐渐减弱或消失。  相似文献   

9.
获取12条流域16 a的753次降雨数据,运用雨强、植被盖度、径流系数和产沙系数等指标,分析黄土高原次降雨径流产沙变化及其与雨强和植被盖度变化的相关性。结果显示:① 与1980-1989年相比,2006-2011年黄土高原的降雨-径流和径流-产沙关系发生了明显变化,大部分流域的产流产沙能力有所下降,10个流域中有8个流域的径流系数、产沙系数有所减小,分别减小25.93%~66.1%和59.05%~97.71%;② 分析雨强和植被盖度变化与径流产沙变化的相关性,发现径流产沙变化与植被盖度变化的相关性强于其与雨强变化的相关性,表明植被盖度变化对径流产沙变化的影响更明显;③ 分析不同干湿条件下径流产沙变化对植被盖度变化的敏感性,发现气候越湿润,流域的径流产沙变化对植被盖度变化越敏感,植被改善的减水减沙效果越明显。  相似文献   

10.
通过长期的飞播造林实践证明:1)在库布齐沙漠西段半荒漠地带高大沙丘设置间距4m平铺行列式沙障和间距6m直立行列式沙障,飞播植物成苗率分别为45.6%和46.2%,比其它类型沙障区的成苗率高出8.9%~30.2%,比未设沙障的对照(CK)区高出36.5%~37.1%。2)种子包衣丸化处理后,沙丘迎风坡等不易落种地段的落种...  相似文献   

11.
GAO Li 《干旱区科学》2022,14(9):993-1008
Guardrail, an important highway traffic safety facility, is mainly used to prevent vehicles from accidentally driving off the road and to ensure driving safety. Desert highway guardrails hinder the movement of wind-blown sand, resulting in the decline of sand transportation by the pavement and the deposition of sand gains on the pavement, and endangering traffic safety. To reveal the influence of guardrails on sand transportation of desert highway pavement, we tested the flow field and sand transport volume distribution around the concrete, W-beam, and cable guardrails under different wind velocities through wind tunnel simulation. Wind velocity attenuation coefficients, sand transportation quantity, and sand transportation efficiency are used to measure sand transportation of highway pavement. The results show that the sand transportation of highway pavement was closely related to the zoning characteristics of flow field and variation of wind velocity around the guardrails. The flow field of the concrete guardrail was divided into deceleration, acceleration, and vortex zones. The interaction between the W-beam guardrail and wind-blown sand was similar to that of lower wind deflector. Behind and under the plates, there were the vortex zone and acceleration zone, respectively. The acceleration zone was conducive to transporting sand on the pavement. The cable guardrail only caused wind velocity variability within the height range of guardrail, and there was no sand deposition on the highway pavement. When the cable, W-beam, and concrete guardrails were used, the total transportation quantities on the highway pavement were 423.53, 415.74, and 136.53 g/min, respectively, and sand transportation efficiencies were 99.31%, 91.25%, and 12.84%, respectively. From the perspective of effective sand transportation on the pavement, the cable guardrail should be preferred as a desert highway guardrail, followed by the W-beam guardrail, and the concrete guardrail is unsuitable. The study results provide theoretical basis for the optimal design of desert highway guardrails and the prevention of wind-blown sand disasters on the highway pavement.  相似文献   

12.
植被沙障对近地表风沙流特征影响的风洞实验   总被引:4,自引:1,他引:3  
植被沙障在一些地区已成为沙害防治的有效手段,其应用也越来越广泛,但对其治沙机理尚不很清楚.在盖度为10%,15%,20%,30%,40%,60%情况下,对植被沙障的防风固沙效益进行了风洞试验.实验风速设置为6,8,11 m/s,测定不同植被盖度的风速廓线特征、风沙流结构特征及其防沙效果.实验结果表明:①积沙总量随盖度增加而逐渐降低,风沙流中的砂粒分布在一定的高度范围内,但分布的高度随盖度的增加呈下降趋势;②植株的茂密程度对风沙流的结构有明显影响,盖度越高,积沙量越集中在下部;③盖度并不是导致积沙量为零的唯一指标,风蚀是否发生,还与植被的疏透度、防护林的高度等有关.  相似文献   

13.
Desertification is one of the most serious environmental problems in the world,especially in the arid desert regions.Combating desertification,therefore,is an urgent task on a regional or even global scale.The Taklimakan Desert in China is the second largest mobile desert in the world and has been called the'Dead Sea'due to few organisms can exist in such a harsh environment.The Taklimakan Desert Highway,the longest desert highway(a total length of 446 km)across the mobile desert in the world,was built in the 1990s within the Taklimakan Desert.It has an important strategic significance regarding oil and gas resources exploration and plays a vital role in the socio-economic development of southern Xinjiang,China.However,wind-blow sand seriously damages the smoothness of the desert highway and,in this case,mechanical sand control system(including sand barrier fences and straw checkerboards)was used early in the life of the desert highway to protect the road.Unfortunately,more than 70%of the sand barrier fences and straw checkerboards have lost their functions,and the desert highway has often been buried and frequently blocked since 1999.To solve this problem,a long artificial shelterbelt with the length of 437 km was built along the desert highway since 2000.However,some potential problems still exist for the sustainable development of the desert highway,such as water shortage,strong sandstorms,extreme environmental characteristics and large maintenance costs.The study aims to provide an overview of the damages caused by wind-blown sand and the effects of sand control measures along the Taklimakan Desert Highway.Ultimately,we provide some suggestions for the biological sand control system to ensure the sustainable development of the Taklimakan Desert Highway,such as screening drought-resistant species to reduce the irrigation requirement and ensure the sound development of groundwater,screening halophytes to restore vegetation in the case of soil salinization,and planting cash crops,such as Cistanche,Wolfberry,Apocynum and other cash crops to decrease the high cost of maintenance on highways and shelterbelts.  相似文献   

14.
With the aid of analyses to landscape ecology in the highway region of the arid area in Xinjiang of China, vegetation type, soil type and land-use type were ascertained as environmental factors of highway landscape ecosystem fragility, and seasonal flood, blown-wind sand and alkali-salinization as disaster factors of highway engineering. All items of these factors constitute an objective hierarchy of evaluating landscape ecosystem risk of the highway region in the arid area. The weighted values of the items were determined according to the number of occupied area or length by them against each unit. The area or length was interpreted with the aids of GIS technology and gained by measuring in the highway reconnaissance. The results of the eco-environmental risk assessment of G315 Yitunbulake-Qiemo section in Xinjiang shows that eight units of landscape ecology can be sorted into four categories according to the differences of the fragility indices (Σxiwi) and the disaster indices (Σyiwj).  相似文献   

15.
塔里木沙漠公路防沙体系的防护效益   总被引:26,自引:7,他引:19  
塔里木沙漠公路全长522km,其中有四百余公里在塔克拉玛干沙漠中穿行,风沙危害十分严重。为了研究适合塔里木沙漠公路的防沙体系和防沙措施,从1991年起在塔里木水公路两公里试验路段开展了公路防沙试验研究,1994年我们对两公里试验路段防沙体系中的各种防沙措施的防护效益进行了调查分析。通过分析可知:a.塔里木沙漠公路尽管风沙害严重,如何采用的防护措施得当,建立起外围阻沙,固沙和边坡防护相结合的防沙体系  相似文献   

16.
Although scientists have performed many studies in the Taklimakan Desert, few of them have reported the blown sand motion along the southern edge of the Taklimakan Desert Highway, which differs significantly from the northern region in terms of aeolian sand geomorphology and formation environment. Based on the field observation data of airflow and aeolian sand transport, continuous monitoring data of erosional and depositional processes between 14 April 2009 and 9 April 2011 and data of surface sand grains from the classical section along the southern edge of the Taklimakan Desert Highway, this paper reported the blown sand motion within the sand-control system of the highway. The main results are as follows: 1) The existing sand-control system is highly effective in preventing and controlling desertification. Wind velocities within the sand-control system were approximately 33%–100% of those for the same height above the mobile sand surface. Aeolian sand fluxes were approximately 0–31.21% of those of the mobile sand surface. Sand grains inside the system, with a mean diameter of 2.89 φ, were finer than those(2.15 φ) outside the system. In addition, wind velocities basically followed a logarithmic law, but the airflow along the classical section was mainly determined by topography and vegetation. 2) There were obvious erosional and depositional phenomena above the surface within the sand-control system, and these phenomena have very consistent patterns for all observation points in the two observed years. The total thicknesses of erosion and deposition ranged from 0.30 to 14.60 cm, with a mean value of 3.67 cm. In contrast, the deposition thicknesses were 1.90–22.10 cm, with a mean value of 7.59 cm, and the erosion thicknesses were 3.51–15.10 cm, with a mean value of 8.75 cm. The results will aid our understanding of blown sand within the sand-control system and provide a strong foundation for optimizing the sand-control system.  相似文献   

17.
科尔沁沙地人工固沙植被优化配置模式试验研究   总被引:1,自引:0,他引:1  
通过对科尔沁沙地7种人工固沙植被配置模式在植物生长季节土壤水分含量、蒸散量和植被盖度的综合分析,优选出可以维持较好的土壤水分状况、形成有效的植被盖度和保障稳定固沙效果的人工固沙植被建立初期的配置模式。结果表明:7种人工固沙配置模式处于人工固沙林定植初级阶段,沙地土壤含水量维持在2.32%~3.41%,基本满足固沙植被水分需求。但在降雨量较低的月份,部分固沙模式土壤含水量表现出较低水平,影响固沙植物的正常生长需求。7种人工固沙植被配置模式蒸散量占同期降雨量94%以上,基本能够维持土壤水量平衡。柠条纯林(525株/hm2)、山竹岩黄芪+沙蒿混交(沙蒿2 800株/hm2、山竹岩黄芪500株/hm2)、山竹岩黄芪(3 300株/hm2)的人工固沙配置模式适合初期建立的固沙工程应用。虽然山竹岩黄芪纯林(3 300株/hm2)固沙模式盖度较高,防风固沙效果好,但由于土壤耗水大,应采取措施,降低其密度。由于小叶杨纯林(1 350株/hm2)的固沙模式土壤耗水较高、植被盖度低,在固沙初级阶段,相对其他6种固沙模式,综合效果较差。  相似文献   

18.
本文以新地—麻黄沟高速公路防沙体系效益为依据,探讨分析了高速公路沙害的特点以及防沙体系建设的基本要求。研究表明,高速公路沙害防治需要采取适当抬高路基,建立稳固的防沙体系并要适当加大防护带宽度的综合措施。该地区公路防沙体系的结构配置对干旱、半干旱沙漠地区高速公路沙害防治具有一定的借鉴作用。  相似文献   

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