SAR影像与光学影像的高斯伽玛型边缘强度特征匹配法

提出了一种基于影像边缘强度图描述的SAR影像与光学影像匹配方法。首先对影像进行粗纠正,消除影像之间的尺度和旋转变化;其次,改进相位一致性特征检测方法,提取对影像相干斑噪声稳健的特征点;然后基于高斯伽玛型双边窗口比值算子计算影像边缘强度图,在此基础上构造不变特征描述符;最后联合几何约束条件,实现SAR影像与光学影像匹配。试验结果证明,与现有方法相比,本文方法能够大幅提高SAR影像与光学影像匹配结果中的正确匹配特征数量以及影像配准精度。     

多光谱遥感影像亮度空间相位一致性特征点检测

提出了一种基于亮度空间和相位一致性理论的多光谱遥感影像特征点检测算法。首先利用参数自适应的灰度变换函数建立影像亮度空间;然后结合相位一致性方法在影像亮度空间进行候选特征点检测,并将候选特征点映射到原始影像上进行非极大值抑制;最后在尺度空间计算特征点的特征尺度值。本文方法有效结合了亮度空间特征检测和相位一致性特征检测的优势,对多光谱遥感影像的辐射变化具有较强的稳健性。试验结果证明,与传统特征点检测算法相比,本文方法在特征重复率和重复特征数量方面都具有明显的优势。     

基于热储法的鲁西平原地热资源评价

鲁西平原地处山东省的西南部,热储层主要有新近系馆陶组、明化镇组,古近系东营组和奥陶系。通过野外勘察和室内分析结果,选取合理的计算参数,利用热储法等对鲁西平原地热资源进行了评价。结果表明鲁西平原地区地热资源量达1.735 5×1021J,折合标准煤5.923 3×1010t;可利用地热资源量达3.252×1020J,折合标准煤1.110×1010t;热储层百年地热水储存量为4.229×1011 m3,地热水允许开发量为4.229×1011 m3。     

An optimized sequential extraction scheme for molybdenum association in environmental samples

By comparing three sequential extraction procedures, a new optimized extraction scheme for the molybdenum association in environmental samples was proposed. Five operational steps were described as exchangeable (KH₂PO₄ + K₂HPO₄: including water-soluble), associated with organic matter (NaOH), Fe–Mn oxides and/or carbonates (HCl), sulfides (H₂O₂) and residue (HNO₃ + HF + H₂O₂). An optimized extraction scheme was compared with Tessier’s procedure and the Commission of European Communities Bureau of Reference (BCR) was applied to black shales. Results showed Tessier’s procedure gave the lowest concentration values for exchangeable molybdenum and the highest values for the residual molybdenum, which could not present the efficiency of the extraction reagents. BCR’s procedure showed the highest values in oxidizable molybdenum and presented four fractions of molybdenum, which did not demonstrate the fractions of molybdenum in the black shales in detail. The optimized extraction scheme demonstrated a certain improvement on extraction efficiency over Tessier’s procedure for the lowest residual molybdenum, and revealed more featured fraction information of molybdenum in black shales than BCR’s. Therefore, after a comparison with other two extraction procedures, the optimized extraction scheme proved suitable for the molybdenum in black shales and it also showed an accurate determination of the molybdenum in the fractions and source of bioavailable Mo.     

Review on Montane Forest Eco-hydrology in Arid Area

Since the forest eco-hydrology of arid area shows a well sensitivity of the global climate change, the relationship between forest and water and the hydrological function has attracted the attention of academic communites and management departments. This paper expounds the research progress in arid mountain forest eco-hydrology, and analyses the formation and stable mechanism of forest patch pattern, the relationship between forest and water yield and the response of forest eco-hydrology to climate change from three aspects: Forest spatial pattern, hydrological process and its response to climate change. In addition, combined with the current research progress, the research emphases in the future are put forward: Strengthening the research on the coupling of vegetation pattern and hydrological process; solving the scale problem by using remote sensing technique and model; enhancing the understanding towards the hydrological function of forest; determining the suitable forest scale which can balance the relationship of ecology and hydrological effect.     

Regional debris flow susceptibility analysis based on principal component analysis and self-organizing map: a case study in Southwest China

A method was developed to analyze the susceptibilities of 541 regional basins affected by debris flows at the Wudongde Dam site in southwest China. Determining susceptibility requires information on source material quantity and occurrence frequency. However, the large number of debris flows can hinder the individual field investigation in a each small basin. Factors that may trigger debris flows can be identified using remotely sensed interpretation information. Susceptibility analysis can then be conducted based on these factors. In this study, SPOT5 satellite imagery, digital elevation models (DEM), a lithology distribution map, and rainfall monitoring data were used to identify 12 debris flow trigger factors: basin relief ratio, slope gradient in the initiation zone, drainage density, downslope curvature of the main channel, vegetation coverage, main channel aspect, topographic wetness index, Melton’s ruggedness number, lithology, annual rainfall, form factor, and cross-slope curvature of the transportation zone. Principal component analysis was used to obtain the eight principal components of these factors that contribute to susceptibility results. Then, a self-organizing map method was adopted to analyze the principal components, which resulted in a debris flow susceptibility classification. Field validation of 26 debris flow basins was used to evaluate the errors of the susceptibility classification, as well as assess the causes of such errors. The study found that principle component analysis and self-organizing map methodologies are good predictors of basin susceptibility to debris flows.     

长江河口北槽河道悬沙絮团特性及其影响因素研究

利用多种先进室内外测量仪器进行河口现场观测和室内电镜扫描获得相关资料,对长江河口北槽河道细颗粒泥沙絮凝的水沙环境、絮团的微观形态结构、絮团的粒径组成及其主要影响因素进行了综合分析和讨论。结果表明,北槽河道具有非常适宜细颗粒泥沙絮凝的潮流、盐度、含沙量和悬沙颗粒粒径等基本环境条件。北槽河道悬沙絮团形态多样,主要包括松散状絮团、蜂窝状絮团和密实状絮团。絮团主要由细粉砂和黏土类细颗粒泥沙组成,表面多粗糙不平,结构或密或疏。絮团粒径变化与潮周期动力过程密切相关,具有周期性变化特征。涨、落憩时絮团粒径较大,涨、落急时絮团粒径较小。絮团粒径涨憩大于落憩,小潮大于大潮。垂向上,絮团粒径由表层至底层逐渐增大。周期性潮流流速对北槽河道悬沙絮团粒径变化起到了控制作用。北槽细颗粒泥沙絮凝作用,是导致疏浚航道发生回淤的主要原因之一。     

近60年来长江河口河势变化及其对水动力和盐水入侵的影响I.河势变化

河势是影响河口水动力和盐水入侵基本因子。本文利用20世纪50和70年代长江河口海图,数值化岸线和水深,结合2012年长江河口实测水深资料,分析长江河口自50年代以来的河势变化。长江河口为分汊河口,50年代仅为二级分汊,至70年代才形成三级分汊,四口入海的河势格局。70年代相比于50年代,北支淤浅严重,其上、中、下段容积变化分别为-64.13×106、-306.60×106和-639.27×106 m3,对应的变化率分别为-16.30%、-22.74%和-25.69%,均显著减小;南支的上、中、下段容积变化分别为-28.61×106、-35.69×106和126.43×106 m3,相应的变化率分别为-1.30%、-2.12%和4.36%;北港由于崇明浅滩和横沙浅滩的淤浅,下段容积明显减小,其上段和下段容积变化分别为109.21×106和-797.14×106 m3,对应的变化率分别为5.01%和-15.25%;南港上段由于河道淤浅容积减小,下段北由于铜沙浅滩被冲开形成北槽,导致水深变深、容积增加,其上段、下段北和下段南容积变化分别为-238.95×106、203.58×106和153.34×106 m3,对应的变化率分别为-8.96%、6.85%和3.26%。2012年相比于70年代,北支由于大量淤浅和围垦容积大幅减小,其上、中、下段容积变化分别为-199.06×106、-504.61×106和-654.12×106 m3,对应的变化率分别为-60.45%、-48.44%和-35.38%;南支的上、中、下段容积变化分别为92.34×106、193.01×106和-163.62×106 m3,相应的变化率分别为4.24%、11.73%和-5.40%;北港上段青草沙水库的围垦和下段横沙东滩的围垦造成面积和容积减小,其上段和下段容积变化分别为-154.64×106和-511.79×106 m3,对应的变化率分别为-6.75%和-11.55%;南港由于上段河道刷深而下段九段沙以及南汇边滩淤浅、围垦,导致其容积上段增加,下段减小,上段、下段北和下段南容积变化分别为136.39×106、-658.28×106和-1266.11×106 m3,对应的变化率分别为5.62%、-20.73%和-26.06%。     

Study of Influence of Regional Geodynamic Background on Strata Behaviors in China's Tongxin Mine

Strata behaviors are mainly affected by regional geodynamic background. The influence of rock mass stress and energy distribution on strata behaviors in the Tongxin mine is studied in terms of regional tectonic movement, seismic activity and tectonic stress field. The results show that the extrusion lifting movement of Kouquan fault adjacent to the Tongxin mine results in the stress concentration in the rock of the Carboniferous coal bed and accumulation of a large amount of elastic energy and forms structural background of Tongxin mine. Due to various seismic activities in the mine area, the strain energy is known to reach much higher levels, up to 0.5×10⁸ J^1/2. Since the stratigraphic structure is sensitive to the mining operation, the strain energy could cause strong strata behaviors. A special geological structure model of the Tongxin mine is established based on the geodynamic division method. The distribution of regional structure stress field is determined by the rock mass stress analysis system. Based on this model, Tongxin mine is divided into five areas with high stress, eight areas with low stress and eight areas with gradient stress. The strong strata behaviors mostly occur in high stress areas. These results could provide guidance to predict the strength of regional or mine pressure and control strata behavior in different areas.