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71.
72.
宁波市陆海及河海管理分界线的界定 总被引:2,自引:0,他引:2
宁波市东临东海,杭州湾和三门湾分别从其北边和南边挟裹,象山港从中间嵌入陆域,与上海、舟山隔海相望,东西宽为175 km,南北长为192 km,海域面积为9 758 km2,大陆岸线全长为1 594 km, 辖区浅海面积为4 524.84 km2.宁波市海岸线由于自然和人为因素不断变化,其中自然的滩涂淤涨使岸线向海推进,人为接连岛工程使海岸线长度增加,而滩涂围垦往往把曲折海岸线变成直线岸线,使总体岸线缩短,这些海岸线变化给陆海管理分界线的确定带来了一定难度.宁波市主要入海河流有钱塘江和甬江,对于入海河流河海管理分界线和部门管理权限尚不清楚,区域管理同样存在多头管理和低效率现象.通过社会调查和实地考察,对宁波市海岸线、海岸带和主要入海河流分布特征以及管理现状进行了深入研究,并根据国际海岸线、海岸带和河海分界理论与实践经验,针对宁波市海岸线和入海河流自然地理环境特征、管理现状和宁波市经济发展的特殊需要,按照我国法律法规的相关规定,我们对宁波市海塘或海堤为界的陆海管理分界线、滩涂或淤涨型岸滩的陆海管理分界线、稳定岸滩的陆海管理分界线、港口码头海域界线、其它海岸工程界址线的界定和大潮高潮痕迹线为围海(涂)内界线的界定以及对钱塘江入海口的河海管理分界线和甬江的河海管理分界线的界定提出了初步建议,旨在为贯彻实施海洋法律法规,进一步加强宁波市海岸带区域开发管理和有效保障海洋管理职能的实现提供理论依据. 相似文献
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ZHU Xiaohua 《中国海洋工程》2000,14(4):533-540
According to the fractal theory,the spatial fractal character of coastline is preliminarily dis-cussed on the basis of GIS in this paper.Two aspects are considered:one is the length demarcation ofcoastline with different scales,and the other is the confirmation of existence of the fractal character on dif-ferent boundaries of tidal flats.Finally,some significant conclusions are drawn:(1)The coastline ofJiangsu Province has the fractal character and its dimension is 1.0696.(2)It conforms to the exponentialcorrelation between different lengths(L)of coastline and scales(k).It conforms to the formula lgL(k)=-1.029lgk+2.9544 in the continental coastline of Jiangsu province.(3)Different boundaries of a tidal flathave fractal characters,and different fractal dimensions indicate different comparative intensities of ero-sion and deposition on the tidal flat.(4)The reciprocity between land and sea may affect the value offractal dimension of a coastline,just as the lithology,substantial constituent and geological s 相似文献
76.
福建省海岸线遥感调查方法及其应用研究 总被引:17,自引:0,他引:17
本文论述了利用遥感技术进行海岸线信息提取的实现方法,提供了完整的遥感调查技术路线,确定了海岸线的遥感解译标志和解译原则,完成了福建省海岸线信息解译工作.利用TM卫星遥感资料解译得出福建省大陆海岸线长度为3102km,其中淤泥海岸约740km,沙滩海岸约268km,基岩海岸约1367km,人工海岸约695km,河口海岸约32km. 相似文献
77.
ROBERT ANDRLE 《地球表面变化过程与地形》1996,21(10):955-962
Mandelbrot (Science, 1967, 156, 636–638) used the west coast of Britain as an example of a naturally occurring statistically self-similar fractal. Evidence from this study indicates that the west coast of Britain is not statistically self-similar over the range of scale of measurement, and that complexity reaches maxima at characteristic scales related to identifiable features on the coastline. A fractal analysis is conducted using the divider method, and although the resulting log–log plot of measured length against steplength appears linear, statistical tests for linearity strongly suggest that the coastline is not statistically self-similar. An angle measure technique (AMT) developed by the author to examine changes in line complexity with scale, shows that within the range of scale of measurement there are two peaks in complexity for the west coast of Britain, suggesting that two processes acting at different scales have influenced coastal development. The AMT is also used to identify differences in complexity between northern and southern sections of the coastline. Additionally, high r2 values associated with regressions of log L(G) against log G are shown to be insufficient evidence of statistical self-similarity, and apparently linear segments (fractal elements) often found in Richardson plots may contain systematic curvature revealed only by more rigorous tests for non-linearity. 相似文献
78.
Coastline configuration indexes of 34 typical arc-shaped coasts in South China are investigated by the method of principal component analysis, and meanwhile deposition and geomorphologic features of arc-shaped coast are also analyzed. The results show: (1) The configuration of arc-shaped coast in South China is of the characteristic of variability and complexity. (2) The wave power and the openings of the bay are the decisive factors to result in the changes of the configuration of the arc-shaped coast in South China, however, incidence direction of the wave has no effect on configuration development of the coast. (3) Commonly, geomorphologic modes of the arc-shaped coast system in South China consist of barriers, lagoons and tidal-inlets, and can be divided into four types:the openings of the bay leaning to the east, the openings of the bay leaning to the south, the openings of the bay leaning to the west and the openings of the bay leaning to the north. 相似文献
79.
This study examined the spatial distribution of the continent coastline in northern China using remote sensing and GIS techniques,and calculated the fractal dimension of the coastline by box-counting method,with a time span from 2000 to 2012.Moreover,we analyzed the characteristics of spatial-temporal changes in the coastline's length and fractal dimension,the relationship between the length change and fractal dimension change,and the driving forces of coastline changes in northern China.During the research period,the coastline of the study area increased by 637.95 km,at a rate of 53.16 km per year.On the regional level,the most significant change in coastline length was observed in Tianjin and Hebei.Temporally,the northern China coastline grew faster after 2008.The most dramatic growth was found between 2010 and 2011,with an increasing rate of 2.49% per year.The fractal dimension of the coastline in northern China was increasing during the research period,and the most dramatic increase occurred in Bohai Rim.There is a strong-positive linear relationship between the historical coastline length and fractal dimension(the correlation coefficient was 0.9962).Through statistical analysis of a large number of local coastline changes,it can be found that the increase(or decrease) of local coastline length will,in most cases,lead to the increase(or decrease) of the whole coastline fractal dimension.Civil-coastal engineering construction was the most important factor driving the coastline change in northern China.Port construction,fisheries facilities and salt factories were the top three construction activities.Compared to human activities,the influence of natural processes such as estuarine deposit and erosion were relatively small. 相似文献
80.
A coastline is defined as the average spring tide line. Different types of seacoast, such as sandy, silty, and bio- logical coast, have different indicators of interpretation. It is very difficult to develop a universal method for interpreting all shorelines. Therefore, the sandy, the silty, and the biological coast are regarded as research objects, and with data mining technolog,found the rules of interpretation of those three types of coastlines. Then, an intelligent coastline interpretation method based on rules was proposed. Firstly, the rules for ex- tracting the waterline in Landsat TM/ETM+ (Thematic Mapper/Enhanced Thematic Mapper Plus) imagery were discovered. Then, through analyzing the features of sandy, silty and biological coast, the indicators of interpreting different types of shoreline were determined. According to the indicators, the waterline could be corrected to the real coastline. In order to verify the validity of the proposed algorithms, three Landsat TM/ETM+ imageries were selected for case studies. The experimental results showed that the proposed methods could interpret the coastlines of sandy; silty, and biological coasts with high precision and without human intervention, which exceeded three pixels. 相似文献