一种空间建模环境及其在生态经济系统中的应用   总被引：1，自引：1，他引：0  

张耀南  韦五周  程国栋 《中国沙漠》2005,25(4):612-617

空间建模和模拟已成为生态系统研究的重要手段,其中SME(SpatialModelingEnvironment)是一个有广泛应用前景的空间建模环境之一。本文首先对SME的结构和功能及其在生态经济系统中应用的两个典型实例进行了介绍,然后介绍了在甘肃省高性能网格计算中心的曙光TC1700高性能计算系统上已建立的SME空间建模环境及其运行验证情况,最后就SME在黑河流域生态系统研究中的应用作了简要展望。  相似文献   

Incision of alluvial channels in response to a continuous base level fall: Field characterization, modeling, and validation along the Dead Sea   总被引：5，自引：1，他引：4  

L. Ben Moshe  I. Haviv  Y. Enzel  E. Zilberman  A. Matmon 《Geomorphology》2008,93(3-4):524-536

The dramatic lake level drop of the Dead Sea during the twentieth century ( 30 m) provides a field-scale experiment in transport-limited incision of gravel-bed channels in response to quasi-continuous base level fall at approximately constant rate. We apply a one-dimensional numerical incision model based on a linear diffusion equation to seven ephemeral channels draining into the Dead Sea. The model inputs include the measured twentieth century lake level curve, annual shoreline location (i.e., annual channel lengthening following the lake level drop), reconstructed longitudinal profiles of each of the channels based on mapped and surveyed terraces, and the current profiles of the active channels. The model parameters included the diffusion coefficient and the upstream-derived sediment flux. Both were first calibrated using a set of longitudinal profiles of known ages and then validated using additional sets of longitudinal profiles.The maximum at-station total incision observed at each of the studied channels was significantly less then the total lake level drop and varied in response to both drainage area and lake bathymetry. The model applied predicted degradation rates and the pattern of degradation with high accuracy. This suggests that sediment flux in the modeled channels is indeed linearly dependent on slope. Further support for this linear dependency is provided by a linear correlation between the diffusion coefficient and the mean annual rain volume over each basin (a proxy for discharge). The model presented could be a valuable tool for planning in rapid base level fall environments where incision may risk infrastructure.  相似文献   

Seismic wave amplification: Basin geometry vs soil layering   总被引：1，自引：0，他引：1  

J.F. Semblat  M. Kham  E. Parara  P.Y. Bard  K. Pitilakis  K. Makra  D. Raptakis 《Soil Dynamics and Earthquake Engineering》2005,25(7-10):529-538

  相似文献   

Modeling abiotic production of apparent oxygen utilisation in the oligotrophic subtropical North Atlantic     

Heiner Dietze  Andreas Oschlies 《Ocean Dynamics》2005,55(1):28-33

Apparent oxygen utilisation is potentially biased by abiotic, physical processes. Using a coupled 3-D circulation-oxygen model, this potential is quantitatively estimated for a region in the eastern subtropical North Atlantic, called the Beta Triangle, where an inconsistency exists between observational estimates of high carbon export from the euphotic zone, based on oxygen utilisation rates in the thermocline (Jenkins 1982), and those of low nutrient supply to the euphotic zone (Lewis et al. 1986, 2004). Our results indicate that in the upper ocean, the Jenkins (1982) estimate is indeed biased high by approximately 10% due to abiotic processes feigning respiration, thus contributing to the apparent inconsistency. Vertical integration, however, yields an abiotic fraction of less than 3%, so the apparent observational discrepancy can not be resolved.Responsible Editor: Franciscus Colijn  相似文献   

三维地质建模及其在地下空间开发中的应用   总被引：1，自引：0，他引：1  

金江军  潘懋  屈红刚  王占刚  明镜 《国土资源信息化》2007,(3):26-29

开发地下空间是许多城市谋求发展的重要途径,也是当前城市建设的重要组成部分。信息化是地下空间开发利用的必然要求,三维地质建模系统具有直观、高效、便利等特点,在城市地下空间开发利用领域有着广阔的应用前景。本文首先阐述了三维地质建模系统的理论方法,给出了三维地质建模流程,介绍了两种三维地质建模方法;然后分析了三维地质建模系统在地下空间选址、地下工程建设、地下空间管理中的应用  相似文献   

Dye dispersion in the surf zone: Measurements and simple models   总被引：1，自引：0，他引：1  

L.B. Clarke  D. Ackerman  J. Largier 《Continental Shelf Research》2007

To examine the spatial and temporal effect of low-volume land-based runoff on beach contamination, discrete batches of dye were released at the shoreline at three beaches in Santa Monica Bay in 2000 (Malibu Creek, Santa Monica Canyon and Pico–Kenter drain). Dye concentration was measured at the shoreline 25, 50 and 100 m alongshore from the dye release point for up to 40 min after dye release. The shoreline concentration time series are characterized either by approximately exponential decay in concentration after passage of the dye patch maximum concentration or by persistent low concentration up to 30 min after passage of the initial dye patch front. In the absence of detailed measurements of physical conditions, several simple advection–diffusion models are used to simulate shoreline concentration time series for an idealized surf zone in order to probe the roles of alongshore current shear and rip currents in producing the observed characteristics in dye concentration time series. Favorable qualitative and quantitative comparison of measured and simulated time series suggest alongshore current shear and rip currents play key roles in generating the observed characteristics of nearshore dye patch dispersion. The models demonstrate the potential effects of these flow features on the extent and duration of beach contamination owing to a continuous contamination source.  相似文献   

Further Study on the Kinetics of Bioremediation of Soils Contaminated with the Herbicide 2,4‐Dichlorophenoxy Acetic Acid     

Morteza Sohrabi  Azadeh Parvizi 《洁净——土壤、空气、水》2007,35(2):193-196

The bioremediation of soil contaminated with the herbicide 2,4‐dichlorophenoxy acetic acid has been studied applying the bacterium Ralstonia eutropha. The effects of temperature, pH, and moisture content of soils on the rate of degradation of this herbicide have been investigated. The Taguchi experimental design method was applied to determine the relative impacts of the pertinent system variables. According to this approach, four series of experiments were performed under various operating conditions. In all four series the herbicide was degraded efficiently, however, the highest rate was observed at a temperature of 35°C, pH 6, and at 80% moisture content of the soil. A kinetic model for the biodegradation of the herbicide was developed for this particular conditions based on the Monod type growth equation and autocatalytic behavior of the decomposition reaction. A close correlation has been observed between the experimental data and those predicted from the model. The degree of agreement was between 85–95%.  相似文献   

Source differentiation, modeling and simulating strong-motion data from Iran     

M.K. Hafizi   《Soil Dynamics and Earthquake Engineering》2007,27(3):212-222

For designing a structure to withstand the effects of strong earthquake ground motions, it is necessary to characterize the type of motion that probably affects the structure. The strong-motion accelerograms contain numerous data regarding the source, path, and receiver. Variables such as the Richter magnitude, hypocenter depth, duration of the event, and focal mechanism relate to the source. The soil parameter and distance to epicenter, relate to the path. The application of autoregressive moving average (ARMA) process in modeling an earthquake accelerogram of three different regions of Iran reveals a formulation, which relates the physical variables via a regression analysis. In order to generate time history data of a probable future earthquake, it is recommended to use the regression equations for a specific type of earthquake focal mechanism if the future earthquake mechanism and physical variables are known; otherwise, regional equations are more suitable.  相似文献   

南海北部陆坡气源条件对水合物成藏影响的模拟研究   总被引：3，自引：1，他引：2       下载免费PDF全文

卢振权  何家雄  金春爽  刘晖  祝有海  杨胜雄  张光学  黄霞  王平康 《地球物理学报》2013,56(1):188-194

南海北部陆坡包括神狐海域在内无论在横向上还是纵向上影响水合物形成与分布的地质因素差异较大,其气源条件的变化是否为一种重要因素值得探索.本文将前人南海北部陆坡气源类型和气体组成概括为14种情况,分别运用模拟手段定量-半定量地分析它们对水合物成藏可能带来的影响.模拟结果显示,与神狐海域已知水合物相比,不同气体组成形成水合物所需温度条件增大0.49~5.44℃,多数增大2℃以上.可以看出,不同气体组成明显改变水合物的形成条件,暗示着不同类型气源可能是影响南海北部陆坡水合物形成与分布的重要因素.  相似文献