A Multiscale Analysis of Coral Reef Topographic Complexity Using Lidar-Derived Bathymetry
A Multiscale Analysis of Coral Reef Topographic Complexity Using Lidar-Derived Bathymetry
复制标题
使用激光雷达测深技术对珊瑚礁地形复杂性进行多尺度分析
DOI：
10.2112/si53-002.1
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发表时间：
2009
影响因子：
2
通讯作者：
J. Brock
中科院分区：
文献类型：
--
作者：
D. Zawada;J. Brock
摘要 珊瑚礁是海洋环境中最不规则的基质之一。这种粗糙度或地形复杂性是珊瑚礁栖息地的重要结构特征，影响许多生态和环境属性，包括物种多样性和水循环。对于珊瑚礁内或不同珊瑚礁系统之间所表现出的地形复杂性范围知之甚少。本研究的目的是量化佛罗里达群岛北部珊瑚礁区沿线 5 公里 x 5 公里珊瑚礁景观的地形复杂性，空间尺度从米到数百米不等。底层数据集是根据激光雷达测量构建的 1 米空间分辨率数字高程模型。使用分形算法对地形复杂性进行量化，该算法提供了珊瑚礁粗糙度的多尺度表征。计算出的分形维数 (D) 是基质不规则性的度量，值介于 2 和 3 之间。D 中的空间模式与该地区已知的珊瑚礁分区呈正相关。研究地点的陆地区域包含相对光滑（D ≈ 2.35）的平顶斑块礁，这些斑块礁逐渐被粗糙（D ≈ 2.5）、深、小丘状的斑块礁所取代。向海边界包含多种基底特征，包括不连续的陆架边缘珊瑚礁，并表现出相应的粗糙度值范围 (2.28 ≤ D ≤ 2.61)。
Abstract Coral reefs represent one of the most irregular substrates in the marine environment. This roughness or topographic complexity is an important structural characteristic of reef habitats that affects a number of ecological and environmental attributes, including species diversity and water circulation. Little is known about the range of topographic complexity exhibited within a reef or between different reef systems. The objective of this study was to quantify topographic complexity for a 5-km x 5-km reefscape along the northern Florida Keys reef tract, over spatial scales ranging from meters to hundreds of meters. The underlying dataset was a 1-m spatial resolution, digital elevation model constructed from lidar measurements. Topographic complexity was quantified using a fractal algorithm, which provided a multi-scale characterization of reef roughness. The computed fractal dimensions (D) are a measure of substrate irregularity and are bounded between values of 2 and 3. Spatial patterns in D were positively correlated with known reef zonation in the area. Landward regions of the study site contain relatively smooth (D ≈ 2.35) flat-topped patch reefs, which give way to rougher (D ≈ 2.5), deep, knoll-shaped patch reefs. The seaward boundary contains a mixture of substrate features, including discontinuous shelf-edge reefs, and exhibits a corresponding range of roughness values (2.28 ≤ D ≤ 2.61).