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1.
陈宝冲THECHANGEOFTHEGENERALFORMANDTHETRANSPORTOFTHEWATER,LOADANDSALTABOUTTHENORTH-BRANCHOFTHECHANGJIANGRIVERMOUTH¥ChenBaochong(N...  相似文献   

2.
RELATIONSHIPBETWEENQINGHAILAKELEVELDESCENDINGANDARTIFICIALWATER-CONSUMPTION¥PengMin(彭敏)ChenGuichen(陈桂琛)ZhouLihua(周立华)(Northwe...  相似文献   

3.
STUDYONGENESISOFHYDROCHEMICALPROPERTYOFFLUIDINCLUSIONSOFMINERALSZhangxiangxunDuShengbao(No.1GeologicalPartyofGuangxi,Guilin)(...  相似文献   

4.
RESEARCHESONSOILENVIRONMENTALBACKGROUNDVALUESINTIBET¥ZhangXiaoping(张晓平)KeYangchuan(科扬川)(ChangchunInstituteofGeography,theChin...  相似文献   

5.
THESTUDYOFGEOELECTROCHEMICALEXTRACTIONMETHODINSEARCHFORHIDDENOREDEPOSITSZhangXuehongLuoXianrong(GuilinInstituteoftechnology)〔...  相似文献   

6.
ASTUDYONTHEFLORAOFWOODYPLANTSOFSHANXIANDTHERELATIONSHIPAMONGTHEFLORAOFSHANXIANDSOMEREGIONS,CHINA①ZhangFeng(张峰)DepartmentofLif...  相似文献   

7.
GLACIER MELTWATER RUNOFF IN CHINA AND ITS NOURISHMENT TO RIVER   总被引:3,自引:0,他引:3  
GLACIERMELTWATERRUNOFFINCHINAANDITSNOURISHMENTTORIVER¥YangZhenniang(杨针娘)(LanzhouInstituteofGlaciologyandGeocryology,theChines...  相似文献   

8.
(张柏)THESTRUCTUREANDDYNAMICSOFTHELANDRESOURCESSYSTEMINTHEFARMLANDSHELTERFORESTREGIONINTHENORTHEASTPLAIN¥ZhangBai(ChangchunInst...  相似文献   

9.
RESPONSEOFRIVERTERRACESTOHOLOCENECLIMATICCHANGESINHEXICORRIDOR,GANSU,CHINA①LiYouli(李有利)YangJingchun(杨景春)DepartmentofGeography...  相似文献   

10.
郭荣星THEECONOMICIMPACTOFSPATIALORGANZATIONALSTRUCTURESONTHEPROVINCIALBORDER-REGIONSOFCHINA¥GuoRongxing(SchoolofEconomicsandTrad...  相似文献   

11.
泛北极是中国“一带一路”倡议的主要合作示范区域,已有的重大线性工程及新的基础设施建设均面临着与多年冻土相关的冻融灾害及工程病害问题。在全球气候变暖及人类活动增强的背景下,泛北极多年冻土主要呈现地温升高、活动层厚度增加趋势,且低温多年冻土地温升高更加明显,20世纪70年代以来年平均地温(MAGT)升温最高可达3℃;自北向南多年冻土活动层厚度增加,且增厚趋势趋于明显,在俄蒙边境地区活动层厚度增速为3~5 cm·年-1。多年冻土退化诱发系列与热喀斯特过程相关的地质灾害,主要包括热喀斯特滑坡与热喀斯特湖,且灾害数量急剧增加,如加拿大Banks Island地区1984~2015年热喀斯特滑坡数量增加了约60倍。在多年冻土退化、热稳定性降低的背景下,泛北极铁路、公路和管道等重大线性工程出现了沉陷、裂缝等不同类型、不同程度的病害,整体上多年冻土区道路工程病害率大于30%。热融灾害及工程病害的发育均与气候及岩土、冻土条件相关,但工程病害还与工程运营期限、工程结构形式密切关联。对比泛北极道路、管道等线性工程状况及其与工程结构的关系,以及病害特征和防治措施效果,表明基于保护冻土的“主动冷却”设计原则依然是多年冻土区工程设计的主导思想。  相似文献   

12.
青藏铁路主要冻土路基工程热稳定性及主要冻融灾害   总被引:5,自引:1,他引:4  
在介绍青藏高原多年冻土退化背景及其工程影响的基础上,通过主要冻土路基现场监测和沿线调查,对青藏铁路冻土路基2002年以来的地温发展过程、热学稳定性及次生冻融灾害进行了分析。结果表明:青藏铁路自2006年通车后冻土路基整体稳定,列车运行速度达100 km/h,达到设计要求,但不同结构路基的热学稳定性不同,采取"主动冷却"方法的路基稳定性显著优于传统普通填土路基。管道通风路基、遮阳棚路基及U型块石路基冷却下伏多年冻土的效果显著,块石基底路基左右侧对称性较差,而处于强烈退化冻土区和高温冻土区的普通路基热稳定性差,需结合路基所在区域局地气候因素予以调整或补强。以热融性、冻胀性及冻融性灾害为主的次生冻融灾害对路基稳定性存在潜在危害,主要表现为路基沉陷、掩埋、侧向热侵蚀等,其中目前最为严重的病害是以路桥过渡段沉降为代表的热融性灾害。  相似文献   

13.
Engineering construction has major influence on the permafrost environment.This paper analyzes the interaction between engineering construction and permafrost environment along the Chaidaer-Muli Railway(simply,CMR) based on the press-state-response(PSR) framework.The permafrost environmental system is divided into three subsystems,consisting of permafrost thermal stability,proneness to the freeze-thawing erosion and permafrost ecological fragility.Each subsystem considers its most important influencing factors.Catastrophe Progression Method(CPM) is applied to calculate the current environment condition along the railway.The result indicates that:(1) as far as the thermal stability is concerned,most sections along the CMR are mainly concentrated in rank Ⅲ(fair situation),and a few in Ⅱ(good situation) and Ⅳ(bad situation),respectively;(2) for the proneness tothe freeze-thawing erosion,the entire railway route falls largely in rank Ⅱ(good situation);(3) along the CMR,the ecological fragility of the permafrost environment is in rank Ⅱ(good situation),or slightly fragile;(4) overall,the permafrost environments along the CMR are in rank Ⅲ(fair situation) or Ⅱcondition(good situation).In general,the permafrost environment along the CMR is fair.It is mainly because a series of active measures of protecting permafrost were taken for stabilizing the CMR foundation soils.On the one hand,we should try our best to minimize the influences that engineering activities have exerted on ecology and environment,on the other hand,the positive measures have made improvements to prevent the permafrost environment from deterioration.  相似文献   

14.
International concerns about the effects of global change on permafrost-affected soils and responses of permafrost terrestrial landscapes to such change have been increasing in the last two decades. To achieve a variety of goals including the determining of soil carbon stocks and dynamics in the Northern Hemisphere. the understanding of soil degradation and the best ways to protect the fragile ecosystems in permafrost environment, further study development on Cryosol classification is being in great demand. In this paper the existing Cryosol classifications contained in three representative soil taxonomies are introduced, and the problems in the practical application of the defining criteria used for category differentiation in these taxonomic systems are discussed. Meanwhile, the resumption and reconstruction of Chinese Cryosol classification within a taxonomic frame is proposed. In dealing with Cryosol classification the advantages that Chinese pedologists have and the challenges that they have to face are analyzed. Finally. several suggestions on the study development of the further taxonomic frame of Cryosol classification are put forward.  相似文献   

15.
Recently, the degradation of permafrost and marsh environments in the Da and Xiao Hinggan Mountains has become a great concern as more human activities and pronounced climate warming were observed during the past 30 years and projected for the near future. The distr/bution patterns and development mechanisms of the permafrost and marshes have been examined both in theories and in field observations, in order to better understand the symbiosis of permafrost and marshes. The permafrost and marshes in the Da and Xiao Hinggan Mountains display discernible zonations in latitude and elevation. The marsh vegetation canopy, litter and peat soil have good thermal insulation properties for the underlying permafrost, resulting in a thermal offset of 3 ℃ to 4℃ and subsequently suppressing soil temperature. In addition, the much higher thermal conductivity of frozen and ice-rich peat in the active layer is conducive to the development or in favor of the protection of permafrost due to the semi-conductor properties of the soils overlying the permafrost. On the other hand, because permafrost is almost impervious, the osmosis of water in marsh soils can be effectively reduced, timely providing water supplies for helophytes growth or germination in spring. In the Da and Xiao Hinggan Mountains, the permafrost degradation has been accelerating due to the marked climate warming, ever increasing human activities, and the resultant eco-environmental changes. Since the permafrost and marsh environments are symbiotic and interdependent, they need to be managed or protected in a well-coordinated and integrated way.  相似文献   

16.
PERMAFROSTDEGENERATIONINTHEEASTOFQINGHAI-XIZANGPLATEAU¥ZhuLinnan;WuZiwang;LiuYongzhi;LiDongqing(StateKeyLaboratoryofFrozenSoi...  相似文献   

17.
Identification of failure susceptible slopes through different rock engineering approach is highly valuable in landslide risk management along crucial highway corridors in the high mountainous region. In this study, a critical highway(NH-5) segment in higher Himalaya has been investigated using the various rock mass characterization schemes based on detailed field observations. Since the highway corridor is highly susceptible to discontinuities-driven failures, consisting of jointed rock masses;Mean and Combined kinematic feasibility analysis has been performed for 20 highway slopes. Observed slope mass classes have been compared to the feasibility percentage of discontinuities driven failures(wedge, toppling, and planar) and accordingly the kinematic feasibility zonation along highway segment has been done for each as well as overall failure types. Based on the slope mass conditions and discontinuities driven failures probability(%), responsive remedial measures have been proposed for individual highway slopes to ensure safe and uninterrupted transportation.  相似文献   

18.
黄河三角洲高效生态经济区的建立,将迎来大规模的基础建设和资源的消耗,从而加剧经济发展—资源消耗—环境污染之间的矛盾。黄河三角洲地区成陆时间较短,地质资源环境比较脆弱,淡水资源相对贫乏,近海地区生态保护及堤防修复压力较大。确定该区地质资源(水资源、土地资源)环境所能承受的人类各种社会经济活动的能力,并预测今后该区大规模人类活动可能对资源环境造成的影响。  相似文献   

19.
利用CSR最新发布的GRACE RL06数据反演2006~2015年三江源地区陆地水储量的时空变化,并结合GLDAS水文模型、TRMM降水数据及地表冻融数据进行对比分析。结果表明,三江源地区的陆地水和地表水在2006~2015年的变化趋势分别为5.2±1.2 mm/a和-3.8±0.9 mm/a;降水与陆地水的变化密切相关,也是造成陆地水储量呈季节性变化的主要原因;冻土作为特殊的蓄水层,影响着三江源地区地表水与地下水之间的水力联系,冻土活动可能造成GRACE与GLDAS水储量之间的差异;根据GRACE与GLDAS水储量在空间趋势上的差异推测,三江源地区高原多年冻土退化,活动层增厚。  相似文献   

20.
This study proposes an equivalent-elevation method to evaluate the integrated effects of latitude and elevation on regional and local-scale permafrost distribution in the Qinghai-Tibet Plateau,and to model the general permafrost-distribution patterns in regional and local-scale area.It is found that the Gaussian curve―an empirical model describing the relation between variations of altitudinal permafrost lower limit (PLL) and latitude in the Northern Hemisphere―could be applied in regional-and local-scale areas in the Qinghai-Tibet Plateau in a latitude-sensitive interval of 30°-50°N.The curve was then used to evaluate the latitudinal effect on permafrost distribution through transforming the latitudinal effect into a kind of altitudinal difference of PLL.This study then calculated the local equivalent-elevation value by overlaying the altitudinal difference of PLL onto real elevation at a certain location.The equivalent-elevation method was verified in an experimental subwatershed of the Qinghai-Tibet Plateau.However,feasibility of the method should be further tested in order to extend for future studies.The use of equivalent-elevation values can build a platform for comparing the regional general permafrost distribution in the plateau,and for basing further evaluations of local factors’ effects on regional permafrost distribution.  相似文献   

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