淤泥质海岸潮滩表层沉积特征遥感研究

发布时间：2018-04-17 11:20

本文选题：多光谱遥感 + 信息提取　；参考：《南京师范大学》2015年硕士论文

【摘要】：潮滩沉积物类型及粒度参数的空间分布可以用来反映潮滩沉积动力环境和水动力条件的变化,预测岸滩的冲淤变化规律。受潮滩自然条件限制,传统的潮滩沉积研究不仅费时费力,而且难以获取大面积的潮滩沉积物信息。遥感技术具有信息量大、覆盖范围广、多时相和不受自然条件限制等优点,在潮滩沉积物研究中相比传统方法具有很大的优势。本文以江苏中部运粮河口至川东港段粉砂淤泥质海岸潮滩为研究区,利用HJ-1A多光谱遥感影像结合野外采样数据为数据源,建立沉积物组分含量(砂、粉砂、黏土)及粒度参数(平均粒径、分选系数、偏态)的遥感反演模型,开展潮滩沉积物分类及粒径运移趋势遥感反演研究,获取沉积物的空间分布规律以及潮滩表层沉积物粒径输运趋势特征,为大范围潮滩沉积研究提供有效技术手段,并为我国海岸带潮滩资源的开发利用提供必要的基础数据和技术支撑。论文的主要研究结论如下：一、HJ-1A影像的近红外波段与沉积物组分含量和粒度参数有明显的线性相关性,分别建立线性相关模型,进行沉积物组分含量和粒度参数的遥感反演,模型验证的平均相对误差分别为19.85%和11.00%,总体反演精度较高；二、利用线性修正的沉积物组分含量遥感反演结果结合Shepard三角分类,获得研究区沉积物的空间分布。可以看出,沉积物在横向方向呈现明显的空间分带特征,总体表现为由陆向海砂含量升高、粉砂和粘土含量降低,沉积物类型主要由砂质粉砂向粉砂质砂过渡；纵向方向由北向南沉积物类型都以粉砂质砂和砂质粉砂为主,砂主要分布在研究区南端大丰港至川东港岸段,这与研究区的水动力环境及沉积物来源相吻合；三、沉积物粒度参数遥感反演结果表现出的粒度参数空间分布整体趋势为：由陆向海,平均粒径和分选系数逐渐减小,偏态系数逐渐增大,即由陆向海沉积物颗粒逐渐变粗、分选变好、偏态由正偏变为极正偏；四、利用遥感反演的沉积物粒度参数空间分布图层驱动GSTA (Grain Size Trend Analysis)模型,得到研究区潮滩表层沉积物的空间运移趋势。总体来看,研究区的沉积物整体呈现沿岸向南和东南方向输运的趋势。在潮滩中上部区域,沉积物主要沿岸线向南或东南方向输运；在潮间带下部,沉积物运移趋势稍显混乱,但多数岸段都表现出垂直岸边向岸运输的趋势。运移的结果导致潮间带下部岸滩向海淤长,滩面逐年增宽；五、为更好的揭示沉积物反演的局部特征,选择射阳河口和大丰潮滩作为典型区域进行潮滩沉积特性分析。研究发现,河口区和港口附近受人类活动的影响,改变了水动力环境和沉积物源供应,潮滩沉积物类型分布和粒径输运趋势更加复杂,主要表现为堤下细颗粒沉积物堆积,潮滩不断淤长,离堤较远的区域与研究区整体情况基本一致。
[Abstract]:The spatial distribution of sediment types and granularity parameters of tidal flat can be used to reflect the change of dynamic environment and hydrodynamic condition of tidal flat and to predict the regularity of erosion and deposition of shoreline.Limited by the natural conditions of tidal flat, the traditional study of tidal flat sediment is not only time-consuming and laborious, but also difficult to obtain a large area of tidal beach sediment information.Remote sensing technology has many advantages, such as large amount of information, wide coverage, multi-temporal phase and not restricted by natural conditions, so it has a great advantage over traditional methods in tidal flat sediment research.In this paper, the silty silt muddy coastal tidal flat in the middle of Jiangsu Province is used as the study area, and the HJ-1A multispectral remote sensing image combined with field sampling data is used as the data source to establish the content of sediment components (sand, silt, silt, silt).The remote sensing inversion model of clay and particle size parameters (mean particle size, sorting coefficient, skewness) is used to study the classification of tidal flat sediments and the trend of grain size migration.The characteristics of sediment spatial distribution and grain size transport trend of tidal flat surface sediment are obtained, which provide an effective technical means for the study of tidal flat sediment on a large scale.It also provides necessary basic data and technical support for the exploitation and utilization of tidal flat resources in coastal zone of China.The main conclusions of this paper are as follows: (1) the near infrared band of HJ-1A image has obvious linear correlation with sediment component content and particle size parameter. A linear correlation model is established to retrieve the sediment component content and particle size parameter by remote sensing.The average relative error of the model verification is 19.85% and 11.00% respectively, and the inversion accuracy is high. Secondly, the spatial distribution of sediment in the study area is obtained by using the linear modified remote sensing inversion results of sediment component content and Shepard triangle classification.It can be seen that there are obvious spatial zonation characteristics in the lateral direction of the sediments, which shows that the content of sand increases from land to sea, the content of silt and clay decreases, and the types of sediment mainly transition from sandy silt to silty sand.In the longitudinal direction, silty sand and sandy silt are the main types of sediment from north to south. Sand mainly distributes in the section between Dafeng Port and Donggang Port in the southern end of the study area, which is consistent with the hydrodynamic environment and sediment source in the study area.The overall trend of spatial distribution of grain size parameters in remote sensing inversion of sediment granularity parameters is as follows: the mean particle size and sorting coefficient decrease gradually, and the skewness coefficient increases gradually, that is, the grain size becomes thicker and thicker from the continental sediment to the sea.The spatial migration trend of surface sediments of tidal flat in the study area is obtained by using the spatial distribution layer of sediment granularity parameters, which is driven by GSTA grain Size Trend analysis model.As a whole, the sediment in the study area is transported along the coast south and southeast.In the middle and upper part of the tidal flat, the main coastal lines of sediments are transported south or southeast, and in the lower part of the intertidal zone, the trend of sediment migration is a little confused, but most of the shoreline show the trend of vertical shoreline transport.The result of migration results in the siltation of the lower intertidal shoreline and the widening of the beach surface year by year. 5. In order to better reveal the local characteristics of sediment inversion Sheyang estuary and Dafeng tidal flat are selected as typical areas to analyze the sedimentary characteristics of tidal flat.It is found that the hydrodynamic environment and sediment source supply are changed due to the influence of human activities around the estuary and port. The distribution of sediment types and the trend of grain size transport in tidal flat are more complicated, mainly as fine granular sediment accumulation under the embankment.The tidal flat is continuously silting, and the area far from the embankment is basically consistent with the whole situation of the study area.
【学位授予单位】：南京师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P737.1;P715.7

【参考文献】