Geomorphic features of the Antarctic margin and Southern Ocean 2012

Publicly available bathymetry and geophysical data has been used to map geomorphic features of the Antarctic continental margin and adjoining ocean basins at scales of 1:1-2 million. The key bathymetry datasets used were GEBCO08 and ETOPO2 satellite bathymetry (Smith & Sandwell 1997), in addition to seismic lines in key areas. Twenty-seven geomorphic units were identified based on interpretation of the seafloor bathymetry with polygons digitised by hand in ArcGIS. Seafloor features were classified largely based on the International Hydrographic Organisation (2001) classification of undersea features, and expanded to include additional features, including those likely to have specific substrate types and influence on oceanography. This approach improves the technique as a predictor of physical conditions that may influence seafloor communities. The geomorphic map has been used for developing a benthic bioregionalisation and for developing a representative system of Marine Protected Areas for East Antarctica. Slight modifications have been made since original publication in O'Brien et al. 2009 and Post et al. 2014. These include:- updating of some feature names;- combining "wave affected banks" with "shelf banks"- Combining "coastal terrance" with "island coastal terrane" as "Coastal/Shelf Terrane"- replacing canyon vectors with polygons by using a buffer around the vectorsFurther details of the original mapping can be found in: O'Brien, P.E., Post, A.L., Romeyn, R., 2009. Antarctic-wide geomorphology as an aid to habitat mapping and locating Vulnerable Marine Ecosystems, Commission for the Conservation of Antarctic Marine Living Resources Vulnerable Marine Ecosystems Workshop, Paper WS-VME-09/10. CCAMLR, La Jolla, California, USA.Post, A.L., Meijers, A.J.S., Fraser, A.D., Meiners, K.M., Ayers, J., Bindoff, N.L., Griffiths, H.J., Van de Putte, A.P., O'Brien, P.E., Swadling, K.M., Raymond, B., 2014. Chapter 14. Environmental Setting, In: De Broyer, C., Koubbi, P., Griffiths, H.J., Raymond, B., d'Udekem d'Acoz, C., et al. (Eds.), Biogeographic Atlas of the Southern Ocean. Scientific Committee on Antarctic Research, Cambridge, pp. 46-64.

本研究采用公开获取的海底测深（bathymetry）与地球物理数据，以1:100万至1:200万的比例尺对南极大陆边缘及毗邻海盆的地貌特征进行成图。本次研究所用的核心海底测深数据集包括GEBCO08与ETOPO2卫星测深数据（Smith & Sandwell, 1997），同时辅以重点区域的地震测线数据。研究人员基于海底测深数据解译，共识别出27个地貌单元，并通过ArcGIS地理信息系统软件手动矢量化生成多边形要素。海底地貌特征的分类主要参考国际海道测量组织（International Hydrographic Organisation, 2001）制定的海底地貌分类标准，并在此基础上扩展纳入了更多特征类型，包括可能具有特定底质类型或对海洋学过程产生影响的地貌单元。该方法可优化对可能影响海底群落的物理环境条件的预测能力。该地貌图已被用于构建南极东部的底栖生物分区体系，并助力建立具有代表性的南极东部海洋保护区（Marine Protected Areas）网络。自2009年O'Brien等人与2014年Post等人的原始成果发表以来，该数据集已进行了小幅优化调整，具体调整内容包括：
- 更新了部分地貌特征的名称；
- 将“受波浪影响的浅滩”与“陆架浅滩”合并为一类；
- 将“海岸地体”与“岛屿海岸地体”合并为“海岸/陆架地体”；
- 通过对峡谷矢量要素构建缓冲区的方式，将原矢量格式的峡谷数据转换为多边形格式。
有关原始成图工作的详细信息可参阅以下文献：
1. O'Brien, P.E., Post, A.L., Romeyn, R., 2009. 南极全域地貌学助力生境制图与脆弱海洋生态系统定位. 南极海洋生物资源养护委员会（Commission for the Conservation of Antarctic Marine Living Resources）脆弱海洋生态系统研讨会, 会议论文WS-VME-09/10. 美国加利福尼亚州拉霍亚市, CCAMLR.
2. Post, A.L., Meijers, A.J.S., Fraser, A.D., Meiners, K.M., Ayers, J., Bindoff, N.L., Griffiths, H.J., Van de Putte, A.P., O'Brien, P.E., Swadling, K.M., Raymond, B., 2014. 第14章 环境背景. 收录于：De Broyer, C., Koubbi, P., Griffiths, H.J., Raymond, B., d'Udekem d'Acoz, C. 等（主编）. 《南大洋生物地理图集》. 南极研究科学委员会（Scientific Committee on Antarctic Research）, 剑桥, 第46-64页.