山区流域高盖度斜坡对极端降雨事件的地下水响应   总被引：2，自引：0，他引：2  

徐则民  黄润秋 《地球科学进展》2011,26(6):598-607

受到日益加剧的全球变暖趋势的强力驱动,极端降雨及与之相伴的山区流域植被发育斜坡的群发性失稳事件在包括中国在内的多山国家的发生频率越来越高,因此对这一问题的深入研究具有重大的现实意义.到目前为止,降雨-滑坡领域的现有研究成果主要集中在并无成因联系的降雨事件与滑坡事件之间的相互关系及斜坡岩土体水岩相互作用方面,而降雨→滑坡...  相似文献   

土壤斥水性及其生态水文效应研究进展   总被引：3，自引：0，他引：3  

刘立超  杨昊天  李新荣  高艳红  贾荣亮 《地球科学进展》2011,26(9):926-932

土壤斥水性是指水分不能或很难湿润土壤颗粒表面的物理现象。土壤斥水性是一个全球性现象,可以出现在各种气候背景、土壤类型和植被覆盖条件下,并且影响到地表水文过程的诸多重要环节,因此受到广泛关注。有关土壤斥水性的研究是表面科学、生物学、土壤学以及物理学等学科交叉的前沿研究领域,已成为国际生态水文学研究的重要核心科学问题。复杂...  相似文献   

黄土旱塬区不同覆盖措施对土壤水分及冬小麦水分利用效率的影响   总被引：4，自引：0，他引：4  

官情  王俊  宋淑亚  刘文兆 《地下水》2011,(1):21-24

田间试验研究了不同覆盖措施对冬小麦农田土壤含水量及小麦生长状况和水分利用效率的影响.试验包括4个处理:作物生育期秸秆覆盖600 kg/ha(M600)、秸秆覆盖300 kg/ha(M300)、地膜覆盖(PM)和无覆盖处理(CK).结果表明:覆盖处理下的土壤贮水量均高于不覆盖,M600处理能显著增加土壤含水量(0～1m和...  相似文献   

鄂尔多斯盆地富县地区奥陶系岩溶风化壳储集层类型与形成条件     

马春生  许化政  郑浚茂  宫长红 《海相油气地质》2011,16(2):42-46

早奥陶世,庆阳-黄陵古隆起北侧形成蒸发台地斜坡白云岩坪膏质白云岩、含膏白云岩沉积.加里东期,该古隆起随同鄂尔多斯盆地整体抬升,其北坡不同层位的石膏质白云岩、含膏白云岩差异溶蚀形成了膏溶角砾白云岩、蜂窝状膏溶细晶白云岩、针孔状膏溶白云岩、粒间溶孔细晶白云岩和溶蚀孔洞泥粉晶碳酸盐岩等不同类型的岩溶储集层.斜坡宽缓、地下水流...  相似文献   

An experimental study of seabed responses around a marine pipeline under wave and current conditions   总被引：1，自引：0，他引：1  

Chunyan Zhou  Guangxue Li  Ping Dong  Jishang Xu 《Ocean Engineering》2011,38(1):226-234

Experiments on three types of soil (d₅₀=0.287, 0.057 and 0.034 mm) with pipeline(D=4 cm) either half buried or resting on the seabed under regular wave or combined with current actions were conducted in a large wave flume to investigate characteristics of soil responses. The pore pressures were measured through the soil depth and across the pipeline. When pipeline is present the measured pore pressures in sandy soil nearby the pipeline deviate considerably from that predicted by the poro-elasticity theory. The buried pipeline seems to provide a degree of resistance to soil liquefaction in the two finer soil seabeds. In the silt bed, a negative power relationship was found between maximum values of excess pore pressure p_max and test intervals under the same wave conditions due to soil densification and dissipation of the pore pressure. In the case of wave combined with current, pore pressures in sandy soil show slightly decrease with time, whereas in silt soil, the current causes an increase in the excess pore pressure build-up, especially at the deeper depth. Comparing liquefaction depth with scour depth underneath the pipeline indicates that the occurrence of liquefaction is accompanied with larger scour depth under the same pipeline-bed configuration.  相似文献   

日照茶树种植区典型茶园的土壤肥力状况评价     

王茂香  张祖陆  王学  张伦  代杰瑞 《山东地质》2011,(7):29-33

通过野外采样和室内测定,以日照茶树种植区3个典型茶园为研究对象,每个茶园分别取鸠坑、黄山群体、福鼎大白各3个品种。最终取得9种茶样生长地的土样,研究分析土样的pH。有机质,全N,P,K,有效N,P,K等指标的土壤养分含量状况,并以此为评价指标,运用模糊综合评判法,对3个茶园的土壤肥力质量进行了综合评价。结果表明,茶园肥力综合水平为北垛春〉碧波山庄〉北叶青i茶园土壤总体上,pH值较适中,有机质含量很缺乏,全N含量偏低,全P含量中等,全K含量较高,有效N含量很缺乏,有效P含量非常丰富,有效K含量中等,并据此提出了关于该地区3个典型茶园今后合理施肥的一些建议。  相似文献   

Downhole well log and core montages from the Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope     

T.S. Collett  R.E. LewisW.J. Winters  M.W. LeeK.K. Rose  R.M. Boswell 《Marine and Petroleum Geology》2011,28(2):561-577

The BPXA-DOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test Well was an integral part of an ongoing project to determine the future energy resource potential of gas hydrates on the Alaska North Slope. As part of this effort, the Mount Elbert well included an advanced downhole geophysical logging program. Because gas hydrate is unstable at ground surface pressure and temperature conditions, a major emphasis was placed on the downhole-logging program to determine the occurrence of gas hydrates and the in-situ physical properties of the sediments. In support of this effort, well-log and core data montages have been compiled which include downhole log and core-data obtained from the gas-hydrate-bearing sedimentary section in the Mount Elbert well. Also shown are numerous reservoir parameters, including gas-hydrate saturation and sediment porosity log traces calculated from available downhole well log and core data.  相似文献   

The characteristics of gas hydrates recovered from the Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope   总被引：1，自引：0，他引：1  

Hailong Lu  Thomas D. LorensonIgor L. Moudrakovski  John A. RipmeesterTimothy S. Collett  Robert B. HunterChris I. Ratcliffe 《Marine and Petroleum Geology》2011,28(2):411-418

Systematic analyses have been carried out on two gas hydrate-bearing sediment core samples, HYPV4, which was preserved by CH₄ gas pressurization, and HYLN7, which was preserved in liquid-nitrogen, recovered from the BPXA-DOE-USGS Mount Elbert Stratigraphic Test Well. Gas hydrate in the studied core samples was found by observation to have developed in sediment pores, and the distribution of hydrate saturation in the cores imply that gas hydrate had experienced stepwise dissociation before it was stabilized by either liquid nitrogen or pressurizing gas. The gas hydrates were determined to be structure Type I hydrate with hydration numbers of approximately 6.1 by instrumentation methods such as powder X-ray diffraction, Raman spectroscopy and solid state ¹³C NMR. The hydrate gas composition was predominantly methane, and isotopic analysis showed that the methane was of thermogenic origin (mean δ¹³C = −48.6‰ and δ_D = −248‰ for sample HYLN7). Isotopic analysis of methane from sample HYPV4 revealed secondary hydrate formation from the pressurizing methane gas during storage.  相似文献   

沈阳市不同功能区地表土壤多环芳烃(PAHs)污染特征研究     

侯伟  刘伟  万志强  宋昀地  陈来仪  李悦  姜磊  苏丹  于海波 《气象与环境学报》2020,36(1):108-112

采用高效液相色谱法对沈阳市地表土壤中的多环芳烃（Polycyclic Aromatic Hydrocarbons,PAHs）进行了定量分析,研究了沈阳市地表土壤中PAHs在不同功能区的含量及分布特征。结果表明：从土壤PAHs总量来看,居民区最低,其次是商业区,交通干道、文教区和公园排在商业区之后,工业区的PAHs总量最多;从PAHs的空间差异来看,靠近工业区以及机动车车流量较大的地区PAHs含量较高,靠近文教区和居住区的地区PAHs含量较低;从PAHs种类来看,所有功能区样品中PAHs的组分分布状况较为一致,以四环PAHs含量最多,其次是五环PAHs和三环PAHs;参考美国EPA沉积物PAHs质量标准和治理标准,沈阳市内五区PAHs总量超过质量标准的功能区有工业区、交通干道（4个采样点,占比36.3%）、文教区（3个采样点,占比75%）和公园区（4个采样点,占比40%）,超过治理标准的功能区有工业区,公园区（1个采样点,占比10%）,文教区（1个采样点,25%）。  相似文献   

Evaluation of Land Surface Scheme SABAE-HW in Simulating Snow Depth,Soil Temperature and Soil Moisture within the BOREAS Site,Saskatchewan     

Alireza Hejazi 《大气与海洋》2013,51(4):408-420

The Soil Atmosphere Boundary, Accurate Evaluation of Heat and Water (SABAE-HW) model is a multilayered, one-dimensional, physically based version of the Canadian Land Surface Scheme (CLASS) and uses the same methodologies as CLASS, version 2.6. SABAE provides an improved interface for groundwater modelling to simulate soil moisture, soil temperature, energy fluxes and snow depth for a wide range of soil and vegetation. This paper reports the results of the first field comparison of SABAE-HW using an extensive ten-year dataset from the Boreal Ecosystem Atmosphere Study (BOREAS) and the Boreal Ecosystem Research and Monitoring Sites (BERMS) project, an area in central Saskatchewan, Canada, rich in terms of hydrological and meteorological data. The model is also independently tested and verified with the Simultaneous Heat and Water (SHAW) model, which is an unsaturated-zone transport model. Two boundary conditions are considered at the bottom of the soil profile: a water table boundary condition and a unit gradient boundary condition. There was substantial agreement between the results of the simulations and observations in terms of snow depth and soil temperature. Snow depth and soil temperature were simulated reasonably well by SABAE, with correlation values of 0.96 and 0.98, respectively. However, there were some discrepancies for simulated soil temperature in winter. General agreement was obtained in terms of unfrozen soil moisture results, especially at greater depths, but there were general similarities in observed and simulated soil moisture trends in winter. An average correlation of 0.55 was found for SABAE while the correlation for SHAW was much smaller (less than 0.30), which indicates a better fit between simulated and field data by SABAE. Although a unit gradient boundary condition does not influence soil moisture, it was found that unit gradient boundary runs resulted in increased bias towards overestimation of the soil temperature. Thus, a safer and more accurate approach, we believe, is to adopt a first type boundary (i.e., water table) condition at the bottom of the domain. This has implications for climate and weather modelling in general. The result of this field testing demonstrated the potential and high accuracy of SABAE-HW as a Canadian model capable of simulating snow depth, snow temperature, soil moisture, energy fluxes, and we believe it is now appropriate to include this land surface scheme with its counterparts.

R ésumé ?[Traduit par la rédaction] Le modèle Soil Atmosphere Boundary, Accurate Evaluation of Heat and Water (SABAE-HW) est une version multicouche, à une dimension, basée sur la physique du schéma CLASS (Canadian Land Surface Scheme) qui utilise les mêmes méthodologies que le CLASS version 2.6. Le SABAE offre une interface améliorée pour la modélisation des eaux sous-terraines permettant de simuler l'humidité du sol, la température du sol, les flux d'énergie et l'épaisseur de la neige pour une grande variété de sols et de végétation. Cet article présente les résultats de la première comparaison terrain du SABAE-HW en utilisant une base de données étendue de dix ans de l'Étude de l'atmosphère et des écosystèmes boréaux (BOREAS) et du projet des Sites de recherche et de surveillance des écosystèmes boréaux (BERMS), une région du centre de la Saskatchewan, au Canada, riche en données hydrologiques et météorologiques. Le modèle est aussi indépendamment testé et vérifié à l'aide du Simultaneous Heat and Water (SHAW), un modèle de transport en zone non saturée. Deux conditions aux limites sont supposées au fond du profil du sol : une condition aux limites de nappe phréatique et une condition aux limites de gradient unitaire. On a trouvé une concordance importante entre les résultats des simulations et les observations en ce qui a trait à l'épaisseur de la neige et à la température du sol. L'épaisseur de la neige et la température du sol ont été raisonnablement bien simulées par le modèle SABAE, avec des corrélations de 0,96 et 0,98, respectivement. Cependant, il y avait certaines divergences pour la température simulée du sol en hiver. Pour ce qui est des résultats concernant l'humidité du sol non gelé, ils s'accordaient généralement, surtout pour les plus grandes profondeurs, mais il y avait des similarités générales dans les tendances observées et simulées de l'humidité du sol en hiver. Nous avons trouvé une corrélation moyenne de 0,55 pour le SABAE alors que la corrélation pour le SHAW était beaucoup plus faible (0,30), ce qui indique un meilleur ajustement des données simulées aux données de terrain pour le SABAE. Même si une condition aux limites de gradient unitaire n'influence pas l'humidité du sol, il ressort que des passes faites avec un gradient unitaire aux limites ont produit un biais accru vers la surestimation de la température du sol. Donc, nous croyons qu'une approche plus sûre et plus précise serait d'adopter une condition aux limites de Dirichlet (c.-à-d. une nappe phréatique) au fond du domaine. Ceci a des répercussions sur la modélisation du climat et du temps en général. Le résultat de cet essai sur le terrain a démontré le potentiel et la grande exactitude du SABAE-HW en tant que modèle canadien capable de simuler l'épaisseur de la neige, la température du sol, l'humidité du sol et les flux d'énergie et nous croyons qu'il est maintenant approprié d'inclure ce schéma de surface avec ses contreparties.  相似文献