CAJ | 학술논문

南海珊瑚礁地貌信息的提取是珊瑚礁资源利用、生态保护与管理及可持续发展的重要地学基础。本文提出了面向对象的珊瑚礁地貌单元提取模型，针对不同的地貌单元，以不同地貌单元的最优分割尺度、光谱参数、形状参数来分割影像并合并成不同对象，从而获得相应的地貌单元。通过大量实验得出自然地貌的最优分割尺度区间为[140,600]，其中附礁生物稀疏带及丛生带、礁坑发育带的光谱参数和形状参数分别为0.9和0.1，其他自然地貌单元的光谱参数和形状参数分别为0.8和0.2；人工地貌的最优分割尺度区间为[25,170]，其光谱参数和形状参数分别为0.8和0.2。进一步以南沙群岛簸箕礁WorldView-2高分辨率遥感影像为例提取地貌单元，并结合混淆矩阵和Kappa系数对分类结果进行了精度评价，地貌单元提取总体精度达到了85.75%，Kappa系数为0.8349。结果表明，该方法可有效运用南海珊瑚礁遥感影像的光谱特征、纹理特征，以及影像数据不同波段的组合特性，综合了影像和珊瑚礁地貌的关联特性，充分利用了珊瑚礁不同地貌相带的异质性，获得了理想的南海珊瑚礁地貌的整体信息，满足了我国南海珊瑚礁地貌信息提取和地貌数字产品生成的需求。
남해산호초지모신식적제취시산호초자원이용、생태보호여관리급가지속발전적중요지학기출。본문제출료면향대상적산호초지모단원제취모형，침대불동적지모단원，이불동지모단원적최우분할척도、광보삼수、형상삼수래분할영상병합병성불동대상，종이획득상응적지모단원。통과대량실험득출자연지모적최우분할척도구간위[140,600]，기중부초생물희소대급총생대、초갱발육대적광보삼수화형상삼수분별위0.9화0.1，기타자연지모단원적광보삼수화형상삼수분별위0.8화0.2；인공지모적최우분할척도구간위[25,170]，기광보삼수화형상삼수분별위0.8화0.2。진일보이남사군도파기초WorldView-2고분변솔요감영상위례제취지모단원，병결합혼효구진화Kappa계수대분류결과진행료정도평개，지모단원제취총체정도체도료85.75%，Kappa계수위0.8349。결과표명，해방법가유효운용남해산호초요감영상적광보특정、문리특정，이급영상수거불동파단적조합특성，종합료영상화산호초지모적관련특성，충분이용료산호초불동지모상대적이질성，획득료이상적남해산호초지모적정체신식，만족료아국남해산호초지모신식제취화지모수자산품생성적수구。
Geomorphology of coral reefs is the foundation for understanding the reef-building process and mech-anism. It is worthwhile to acquire the geomorphological information of coral reefs in the South China Sea be-cause this information can provide valuable insights for the resources utilization, ecological protection and man-agement as well as sustainable development of coral reefs in China. Based on the development of current remote sensing techniques, an object-oriented geomorphic unit extraction method for coral reefs is proposed in this pa-per. The satellite images are segmented by the optimal scales, spectral parameters and shape parameters and the segmented objects are combined to different objects to obtain the geomorphic units. Through a large number of experiments, the optimal scales for natural geomorphic units range from 140 to 600. Spectral parameters and shape parameters for sparse reef associations zone, numerous reef associations zone, and reef pits development zone are all 0.9 and 0.1, respectively. Spectral parameters and shape parameters for other natural geomorphic units are 0.8 and 0.2, respectively. On the other hand, optimal scales for man-made geomorphic units range from 25 to 170, while their spectral parameters and shape parameters are all 0.8 and 0.2, respectively. The WorldView-2 high resolution remote sensing image of Boji Reef in Nansha Islands is used as experimental data in this paper and the accuracy of classification results is assessed with the confusion matrix and Kappa coefficient, the overall accuracy of geomorphic unit extraction reaches 85.75%and the Kappa coefficient is 0.8349. The results show that this method can effectively take advantage of the features of spectra, texture and the stacking of different wave-bands of satellite images. In addition, this method can grasp the correlation of satellite image and reef geomor-phic zonation and make full use of the heterogeneity of reef geomorphology. Therefore, an ideal geomorphic zo-nation that has a higher accuracy can be obtained to acquire geomorphological information and produce geomor-phological digital products of coral reefs in the South China Sea.