共查询到18条相似文献,搜索用时 78 毫秒
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对地下水水源地进行保护区划分将提高地下水的安全保障程度。岩溶水型水源地由于含水层的非均质、各向异性的特点,难以合理准确的划分水源地保护区。以济南市曹楼水源地为研究对象,在充分收集和分析水源地水文水质、地形地貌等资料的基础上,采用组合法划定水源地保护区,结合地形地质条件对保护区范围进行修正,保护水源地免受污染。利用组合法划分的水源地保护区加强了对上游补给区,尤其是地下水主径流带的保护,划分结果更符合实际。利用该方法能提高对水源地主要补给区的保护,保障地下水的可持续开发利用,为水源地的保护提供科学的依据和参考。 相似文献
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岩溶隧道是否发生涌突水,主要取决于洞身岩溶发育程度和岩溶系统结构类型,而这与岩溶系统的演化过程密切相关。岩溶系统的发育演化始于具有侵蚀性的水对可溶性岩体中裂隙的溶蚀扩展。基于此,本研究耦合了渗流模型和溶蚀扩展模型,并结合鸡公岭隧道区水文地质背景资料,建立了隧道区岩溶系统岩溶演化模拟模型,模拟再现了隧道区岩溶含水介质的发育情况。结果显示:随着岩溶系统的发育演化,整个系统中裂隙不断被溶蚀扩展,差异性溶蚀越来越显著,岩溶含水介质的非均质性越来越强;同时随着埋深的增加,岩溶发育程度及非均质性越来越弱;浅部和深部裂隙的平均溶蚀扩展率相差近1 500倍;鸡公岭隧道洞身标高处岩溶发育微弱,裂隙溶蚀扩展较小,仍为裂隙岩体,其等效渗透系数为0.51m/d,岩溶突水概率极低,隧道发生涌水时的涌水量为127.9m3/d,对隧道施工影响较小。 相似文献
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2011年以来,中国地质调查局在沂蒙山区组织实施了1∶5万标准图幅水文地质调查4万余km2,并在严重缺水村镇开展了大量的找水打井示范工作,获得了较为丰富的地质数据,对断陷盆地地下水流系统取得了新认识。受中新生代构造影响,沂蒙山区发生断裂褶皱、伸展滑脱及岩浆侵入活动,形成一系列“南超覆北断陷”的地堑—半地堑盆地,并最终形成现今典型的“盆—山”岩溶水文地质结构,及以盆地为单元的相对独立的岩溶地下水流系统。为研究沂蒙山区地下水流系统发育特征,选择莱芜盆地为典型研究区,基于野外地质调查,通过综合分析盆地南北两侧地貌单元、含水岩组立体空间分布及地下水水位、水化学及同位素结果等,探讨了沂蒙山区典型“盆—山”结构塑造的多级岩溶地下水流系统特征。结果表明,莱芜盆地岩溶地下水由盆地外围向盆地中心呈“向心式”径流;受人类活动影响、地质构造控制和含水层分布制约,盆地南北两侧地下水流系统特征存在差异:盆地南部发育中间和局部两级地下水流系统;盆地北部则仅发育单一的局部地下水流系统,但占有已勘查论证的近1/2的地下水水源地。此外,研究发现在大汶河最低侵蚀基准面,区域滑脱构造及热液混合作用拆离... 相似文献
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文章借助信息熵和均衡度的概念,揭示淮阴区1998-2008年土地利用结构的动态演变规律.其信息熵先后经历了"上升-稳定-再上升-下降"四个阶段,总体呈上升趋势.在不同土地利用类型中,耕地、园地、林地等与土地利用结构信息熵负相关,居民点及工矿用地、交通用地等与土地利用结构信息熵正相关.最后,对淮阴区如何优化土地利用结构提... 相似文献
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地学信息图谱是一种现代信息技术条件下的地理时空分析方法论。本文阐述了土地利用结构优化图谱的时空尺度、情景过程、层次结构、图谱和模型的互馈等科学问题。提出遥感影像信息源和前期工作产生的土地利用现状、生态安全单因子评价系列的征兆图谱,中期工作得出的生态安全及土地利用综合评价系列的诊断图谱,后期的土地利用优化情景系列的实施图谱。各层次图谱在分类和分级体系上要具有一定的统一协调性。科尔沁沙地八仙筒镇的优化实例表明,应用地学信息图谱进行土地利用结构优化可以实现对过去、现在和未来的反演、评价和预测,进而为区域土地可持续发展提供决策依据。 相似文献
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采用深圳市2010年、2015年和2016年的土地利用现状数据,运用FLUS模型对自然发展情景、生态安全情景和生态优化情景3种情景下2030年深圳市土地利用结构和空间布局的变化进行模拟。研究结果表明:以2010年为基期模拟2015年土地利用布局的kappa指数为0.862,模拟结果较为理想。3种情景下深圳市2030年土地利用布局既有共性也存在差异。生态优化情景在禁止建设区把部分生产性用地转变为具有重要生态功能的林地,在限制建设区严格控制新增建设用地,在集中连片的控制区内限制生产活动,比自然发展情景和生态安全情景更能达到城市建设和生态保护的双重目标。 相似文献
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人工示踪试验是岩溶水文地质领域的重要研究手段,分别在基流期和降水条件下对苍蒲凹地下河实施了多源示踪试验,以探究其岩溶管道的展布特征。试验结果显示,基流期和降水条件下均检测到来自水箐、黄连村及廖家坡3个落水洞的示踪剂,降水条件下的示踪剂回收率分别为88.12%,90.01%,84.01%,表明苍蒲凹地下河为多源单汇型地下河。基流期及降水条件下示踪剂运移特征均表明,水箐至苍蒲凹的流动路径曲率最大,黄连村至苍蒲凹的流动路径为主岩溶管道,廖家坡至苍蒲凹的流动路径上存在双通道,且在靠近地下河出口处存在溶潭,据此建立了苍蒲凹地下河管道结构的概念模型。研究成果可为复杂岩溶地下河的水资源调查及开发利用提供依据。 相似文献
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水封性是保证地下水封洞库安全运营的关键,目前研究地下水封洞库水封性的主要难点在于裂隙岩体含水层强烈的非均质性和各向异性。以某地下水封洞库工程为背景,通过实测裂隙几何参数分析裂隙发育特征,建立了研究区离散裂隙网络模型。之后对研究区进行网格化划分计算了各单元体渗透系数张量,基于对裂隙渗流基本规律的理解和假设建立了研究区高精度的非均质各向异性渗流模型,并对研究区渗透性特征进行分析。通过建立非均质各向异性渗流模型对水幕系统水封性能进行了探讨并与传统均质各向同性渗流模型进行对比分析,利用该模型可以弥补传统均质各向同性渗流模型的不足,更加准确地评价由于裂隙岩体非均质各向异性造成的储品泄漏风险。 相似文献
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Groundwater is one of the most important resources, its monitoring and optimized management has now become the priority to satisfy the demand of rapidly increasing population. In many developing countries, optimized groundwater level monitoring networks are rarely designed to build up a strong groundwater level data base, and to reduce operation time and cost. The paper presents application of geostatistical method to optimize existing network of observation wells for 18 sub-watersheds within the Wainganga Sub-basin located in the central part of India. The average groundwater level fluctuation (GWLF) from 37 observation wells is compared with parameters like lineament density, recharge, density of irrigation wells, land use and hydrogeology (LiRDLH) of Wainganga Sub-basin and analyzed stochastically in Geographic Information System (GIS) environment using simple, ordinary, disjunctive and universal kriging methods. Semivariogram analyses have been performed separately for all kriging methods to fit the best theoretical model with experimental model. Results from gaussian, spherical, exponential and circular theoretical models were compared with those of experimental models obtained from the groundwater level data. Spatial analyses conclude that the exponential semivariogram model obtained from ordinary kriging gives the best fit model. Study demonstrates that ordinary kriging gives the optimal solution and additional number of observation wells can be added utilizing the error variance for optimal design of groundwater level monitoring networks. This study describes the use of Geostatistics methods in GIS to predict the groundwater level and upgrade groundwater level monitoring networks from the randomly distributed observation wells considering multiple parameters such as GWLF and LiRDLH. The method proposed in the present study is observed to be an efficient method for selecting observation well locations in a complex geological set up. The study concludes that minimum 82 wells are required for proper monitoring of groundwater level in the study area. 相似文献
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Kebiao Mao Ying Ma Lang Xia Xinyi Shen Zhiwen Sun Tianjue He Guanhua Zhou 《中国地理科学(英文版)》2014,24(5):599-606
It has been observed that low temperature, rainfall, snowfall, frost have never occurred over the past 50 years in the southern China, and weather in this area is very complex, so the monitoring equipments are few. Optical and thermal infrared remote sensing is influenced much by clouds, so the passive microwave Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) data are the best choice to monitor and analyze the development of disaster. In order to improve estimation accuracy, the dynamic learn- ing neural network was used to retrieve snow depth. The difference of brightness temperatures of TB18.7v and TB36.sv, TBI8.7H and TB36.sH, TB23,sv and TB89v, TBz3.8H and TB89H are made as four main input nodes and the snow depth is the only one output node of neural network. The mean and the standard deviation of retrieval errors are about 4.8 cm and 6.7 cm relative to the test data of ground measurements. The application analysis indicated that the neural network can be utilized to monitor the change of snow intensity distribution through passive microwave data in the complex weather of the southern China. 相似文献
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Catchments health assessment is fundamental to effective catchments management. Generally, an as-sessment method should be selected to reflect both the purpose of assessment and local characteristics. A trial in Shanghai was conducted to test the method for catchments health assessment in urbanized river network area. Seven indicators that described four dimensions of river, river network, land use and function, and local feature were used to assess catchments values; while possible change rate of urbanization and industrialization in the next 3 years were chosen for catchments pressure assessment in the value-pressure model. Factors related to catchments classi-fication, indicators measurement and protection priority have been considered in the development strategies for catchments health management. The results showed that value-pressure assessment was applicable in urbanized catchments health management, particularly when both human and catchments had multiple demands. As a result of over 30-year rapid urbanization, more than 70% of Shanghai river network area was still in a healthy condition with high catchments values, among them, 39.3% was under high pressure. Poor water quality, simplified river system and weakened local feature of river pattern had largely affected catchments health in Shanghai. Lack of long-term monitoring data would seriously restrict the development and validity of catchments health assessment. 相似文献
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Xichou County of Wenshan Zhuang and Miao Autonomous Prefecture in southeast Yunnan is one of the karst mountainous areas in southwest China showing typical rock desertification. During this study, we set up three soil erosion contrast test spots at Muzhe Village, Benggu Township, Xichou County, which was the birthplace of the Xichou rock-desertified land consolidation mode. The three spots included the terrace land spot (already consolidated land), sloping land spot (unconsolidated sloping land under rock desertification), and standard runoff spot (bare land spot). In 2007, a whole-year complete observation was conducted during the rainy season and "rainfall-erosion" data were obtained for 32 times. Our analysis showed that during the entire observation period, the number of the rainfalls that led to soil erosion accounted for 34.04% of the number of all rainfalls and the amount of the rainfalls that led to soil erosion accounted for 84.17% of the total amount of all rainfalls. The average erosive rainfall standard in the three test spots was 11.0 mm, slightly higher than the 10 mm standard that has been adopted all over China, but lower than the 12.7 mm standard of the US and the 13.0 mm standard of Japan. According to single-factor analysis, the soil loss in the sloping land spot (L2) and that in the bare land spot (L3) are correlated to certain extent to many other factors, including the single precipitation (P), rainfall intensity during the maximum ten minutes (I10), rainfall intensity during the maximum 20 minutes (I20), rainfall intensity during the maximum 30 minutes (I30), rainfall intensity during the maximum 40 minutes (I40), and rainfall intensity during the maximum 60 minutes (I60). Among these factors, they are of the highest relativity with I60. According to double-factor analysis, both L2 and L3 are of good relativity with P and I60. According to multi-factor analysis, L2 and L3 are also of good relativity with seven rainfall indexes, namely, P, Ia (average rainfall intensity), I10, I20, I30, I40, and I60, with their related coefficient R reaching 0.906 and 0.914, respectively. The annual soil losses in the three test spots are widely different: 1030.70 t/km2·a in the terrace land spot, which indicates a low-level erosion; 12913.22 t/km2·a in the sloping land spot (unconsolidated spot), some 12.5 times than that in the terrace land spot, which indicates an ultra-high-level erosion; and 19511.67 t/km2·a in the bare land spot, some 18.9 times than that in terrace land spot, indicating an acute erosion. These figures fully show that the Xichou rock-desertified land consolidation mode plays a significant role in soil conservation. 相似文献
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Land Use Allocation Based on Interval Multi-objective Linear Programming Model: A Case Study of Pi County in Sichuan Province 总被引:2,自引:1,他引:2
Adjusting and optimizing land use structure is one of the essential approaches to solve the conflict between land supply and demand. In this study,an uncertain interval multi-objective linear programming model was established and applied to analyzing the suitability of land use structure in Pi County of Sichuan Province. An adjustment scheme for optimizing land use structure was proposed on the basis of development planning drawn up by the local government. The results are summarized as follows: 1) the opti... 相似文献
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区域化探数据中包含了丰富的地质信息,提取出蕴含在这些数据中的地质体空间分布信息,对于区域地质研究和找矿勘查具有重要意义。区域化探数据通常包括数十个元素,属于高维数据,隐藏在这些高维数据中的地质体空间分布信息无法直接从数据中观察到。针对这个问题,构建了一个基于t分布随机近邻嵌入(t-distributed stochastic neighbor embedding,简称t-SNE)算法的高维区域化探数据降维可视化模型。t-SNE算法是一种非线性降维方法,特别适用于高维数据集的降维和可视化。选择对岩性鉴定比较稳定的元素,通过t-SNE算法将高维化探数据降维到人眼可观察的一、二、三维,把降维之后的变量表达为栅格图,通过三原色混合等方法进行可视化,从而把隐藏在高维化探数据中的地质体空间分布信息可视化表达出来。以英格兰西南部某地区水系沉积物区域化探数据为例进行研究来检验t-SNE算法在高维化探数据可视化上的实际应用效果。结果显示:①通过t-SNE算法对高维化探数据进行可视化得到的结果能够很好地反映研究区的地质体空间分布情况;②可视化的效果与t-SNE算法的目标维度和复杂度两个参数密切相关。在t-SNE算法中设定要降维到的目标维度越高,所显示的地质体信息越详细。③基于t-SNE算法的化探数据降维可视化效果比基于主成分分析(PCA)的化探数据降维可视化效果更好。本文研究表明基于t-SNE算法的化探数据降维可视化方法能够很好地将地质体空间分布信息可视化表达出来,对于推断地质体的空间分布有一定的指导意义。 相似文献