【作者】 邱海军；

【导师】 曹明明； 惠泱河；

【作者基本信息】 西北大学 ， 自然地理学， 2012， 博士

【副题名】以宁强县为例

【摘要】 地质灾害作为一种破坏性的地质事件,经常对人类的生命财产和生存环境构成严重威胁,制约着人类的可持续发展。经过几十年的探索,我国在地质灾害研究领域取得了丰硕的成果。但总体来说,与国际先进水平相比还存在着一定的差距。特别是对于区域地质灾害的自组织临界性、幂律相依性、频率空间相依性和规模参数对数正态分布性等方面,缺乏定量的认识;在区域地质灾害评价因子筛选与分析、易发性及危险性评价方面也有许多问题值得深入探索。宁强县地处秦巴山区,地质灾害充分发育,发生频率高,分布点多面广,是陕西省地质灾害重灾县之一,也是进行区域地质灾害特征分析和危险性评价的良好实验基地。基于此,本文以宁强县为例,依托陕西省“13115”科技创新工程重大科技专项项目(2008ZDKG-75)"基于3S技术的陕西省宁强县强震次生灾害监测评估研宄”,在小比例尺地质灾害详查和SPOT5等遥感数据解译基础上,建立了详细的地质灾害编录数据库。对地质灾害的某些特征进行了定量分析研究,对该区域地质灾害的易发性和危险性进行了评价与分区,最后对风险管理进行了探索。取得了以下主要成果：1.定量的探索和揭示了区域地质灾害某些特征：①宁强县地质灾害以滑坡为主,崩塌、泥石流次之。在地域分布上,呈现一带三区；在规模类型上,以小型为主,但特大型和巨型滑坡崩塌控制着滑坡崩塌总面积和总体积：在形态分布上,以半圆型和等长式滑坡为主；在物质组成上,滑坡以土质堆积层滑坡为主,崩塌以岩质崩塌为主；在空间分布上,既有分散性又有聚集性。聚集性有规模上的集聚性、受威胁对象的集聚性,有时间上的聚集性和空间上的聚集性等。特别是在空间聚集性上,本文通过最近邻分析法和Ripley K函数法进行了验证。②通过定量分析频率与规模之间的数量关系,探索了地质灾害的自组织临界性,并在国内首次发现了当滑坡规模较小时,在双对数曲线上滑坡崩塌频率出现“偏转效应”。③提出了地质灾害规模参数的幂律相依性,这在国内研究处于空白状态,即使是国外的研究也仅限于对体积与面积幂律相依性的讨论。本文在揭示体积与面积幂律相依性的基础上,进一步提出面积与长、宽等参数之间的幂律相依性,并给出了公式。④定量分析了地质灾害的分形与变维分形特征,采用盒维数法计算了单体滑坡和空间地质灾害分布的分形维数,并以滑坡空间分布与高程、坡度的关系为例,揭示了其变维分形特征。⑤论述了地质灾害频率的空间相依性及其分区,指出地质灾害频率是地质灾害的空间分布参数,在进行滑坡崩塌地质灾害评价分区时必须选择一个合理的目标区域：区域地质灾害分区、线性地质灾害分区和场地地质灾害分区。⑥指出了地质灾害参数的对数正态分布特征,通过箱式图和QQ图进行了验证,并用正态、韦伯和Logistic分布曲线进行了拟合。2.论述了制图单元的选择,将制图单元归结为5类：网格单元、地域单元、均一条件单元、斜坡单元和地形单元。根据研究需要,文中选择了斜坡单元和网格单元进行地质灾害的评价。3.建立了较为完善的区域滑坡崩塌地质灾害评价指标体系,通过定性与定量相结合的方法,系统分析和阐述了地质灾害与其评价因子之间的关系。采用信息量法、Logistic回归法、人工神经网络法和支持向量机等方法进行了易发性评价,采用乘积法和综合法进行了危险性评价。在此基础上,将宁强县地质灾害的易发性划分为3个分区,分别为：高易发区、中易发区和低易发区。危险性分为3个分区,分别为：高危险区、中危险区和低危险区。4.系统的提出了对地质灾害易发性评价结果比较的意义与方法,指出分类关乎成本,误分类类型不同,其成本也有很大的不同。并将模型准确性统计按照其是否受临界值约束这一条件分为受临界值约束和不受临界值约束两类。并采用ROC曲线、Kappa系数和成功率曲线等性能评价方法对各种方法和模型的易发性评价结果进行了比较分析,结果表明：相比于其它模型与方法,人工神经网络模型模拟计算结果更客观、更合理。5.探索了地质灾害事件的概率和频率分布,采用泊松分布模型对宁强县滑坡在不同面积、体积等级上5年、10年和50年的超越概率进行了计算。并将地质灾害的频率分为：绝对频率、相对频率和间接频率；最后,通过考虑过去地质灾害活动程度和未来影响因素来间接反映地质灾害的频率。6.探讨了地质灾害的风险及其风险管理和风险可接受水平,有针对性的建立了地质灾害风险管理体系以及控制途径。描述了地质灾害的矛盾性,风险的动态性等,进而指出灾害系统的实质是地球表层系统中的“人类-自然耦合系统”。更多还原

【Abstract】 As a destructive geological event, geological disasters affect human life,property and living environment seriously, and restrict the sustainable development of human beings. In spite of our country in the field of geological disasters has achieved fruitful results during the past several decades,on the whole, In comparison to the international advanced level there are large gaps. Especially for certain characteristics of regional geological disaster, such as self-organized criticality, power-law dependence, laggregation,spatial-dependence of frequency and log-normal of parameters of scale, lack of qualitative or quantitative cognition. About the assessment of regional geological disasters, such as deep and systematic analysis of impact factor, comparison of results of susceptibility assessment,frequency on geological hazard and other related fields,there are exploration space. Ningqiang County is located in Qin-Ba mountains, there are many geological disasters.they has the extensive distribution in Shaanxi Province.but it is also a good experimental base for characteristic analysis and hazard assessment of geological disaster. Therefore, this paper takes Ningqiang county as an example, which in Hanzhong city of Shaanxi province, on the back of "13115" science and technology innovation engineering major technology special project (2008ZDKG-75) named"The evaluation research of secondary disasters based on3S technique in Ningqiang county of Shanxi Province", and then established the detailed catalogue of geological disasters and the database based on scrutinize in small scale geological disasters and the interpretation of remote sensing data such as SPOT5. On the bases of above, fist, analysis the characteristics of geological disaster systematically, then do some researches on susceptibility assessment and do some exploratory study on risk assessment of Ningqiang country, finally discusses the risk of geological disasters and risk management briefly. Made the following main conclusions:1. Some features of the regional geological disasters were explored and revealed quantitatively as below:①The main type of geo-hazard is landslide in Ningqiang county and the second is landfalls and debris flow. In the regional distribution, the types of geological hazards present1belt and3areas.In the scale, mainly with small, but the total area and the bulk volume of the landslide and collapse were controlled by large and giant landslide; In the distribution pattern, primarily with half-round and equal-length landslide; In the material composition, the main type of landslide is soil and debris landslide and collapse is rock collapse; In the space distribution, the types of geo-hazard have the characteristics of dispersion and clustering; the characteristic of clustering are showed in the scale, the threatened object, time and space. Especially in the clustering of space, this article further verified the characteristic of clustering by the nearest analysis and Ripley K function method.②Self-organized criticality of geological disasters was explored quantitatively by analysis the relationship between frequency and scale. And found "rollover effect" of frequent of landslides and collapse at home for the first time in double logarithmic coordinate when the scale of landslide is small.③Power law dependency of scale parameter of geological disasters was put forward, which was blank in the research at home and limited to power law dependency discussion on volume and area on abroad. This paper further put forward power law dependency between the parameters of area, length and width on the basis of revealing the power law dependency of volume and area, and put forward the formula.④The fractal and variable dimension fractal feature of geological disasters were analyzed quantitatively, calculate fractal dimension of monomer landslide and space distribution of geological disasters by using the box counting dimension method, and took the relationship of space distribution of landslide between elevations and slope for example, reveals its variable dimension fractal feature.⑤The frequency of space dependency and zoning of geo-hazard were discussed, putting forward the frequency of geo-hazard is the parameters of spatial distribution of geo-hazard. A reasonable target area should be chose when making evaluation zone of geo-hazard:regional geo-hazard zone, linear geo-hazard zone and the field zone.⑥The logarithm normal distribution characteristic of parameters of geo-hazard was pointed out, which was verified by box figure and QQ figure and fitted with normal, Weibull and Logistic distribution curves.2.The selection of mapping unit was discussed and the mapping unit comes down to5kinds:the grid unit, regional unit, uniform conditions unit, slope unit and terrain unit. According to the needs, the evaluation of the geological hazard in this paper chose slope unit and grid unit.3. An integrated index system of regional geo-hazard assessment has been established, the relationship between the geo-hazard and their evaluation factor has been analyzed and discussed systematically.By using information model, Logistic regression model, artificial neural network and support vector machine method to evaluate geo-hazard susceptibility,and using product method and synthesis method to evaluate landslide hazard. On this basis, divided landslide susceptibility of Ningqiang County into three zones:high susceptibility zones,middle susceptibility zones and low susceptibility zones. divided landslide hazard into three zones:high middle and low hazard zone.4. Provided the significance and method of comparison of assessment results of landslide susceptibility, pointed out that the classification relates to the cost. the costs are very different in different type of misclassification error. Accuracy statistics of model were divided into cutoff-dependent performance criteria and cutoff-independent performance criteria according to whether the statistics are constrained by the critical value.At last,by using the method of receiver operating characteristic, cohen’s kappa and success-rate curves to make comparative analysis of susceptibility assessment.The results showed that:compared to other models and methods, the simulation results of artificial neural network model was more objective and reasonable.5.The geo-hazard in the probability of events and frequency distribution were explored, and the exceeding probability of landslide in different classes of area, volume on five years.10years and50years in Ningqiang county was calculated by using poisson distribution model. The frequency of the geological disasters is divided into:absolute frequency, relative frequency and indirect frequency, and the frequency of geo-hazard were reflected indirectly through geo-hazard in the past and future activity.6.The risk of geo-hazard, risk management and risk acceptable level were discussed, and the geological disaster risk management system and control system were established. In this article, the contradiction in geological disasters and the dynamic of risk were described. and pointed out that the essence of the disaster systems is "human-natural coupling system" in earth surface system.更多还原