Abalone fishing block 27 - High resolution acoustic data of reef habitat

The principle aim of this project was to map the fine-scale spatial distribution of key abalone habitat impacted by urchins in < 25 m water depth using multibeam acoustic imagery. Detailed substrate type (Pavement Reef, Megaclast Reef, Mixed Consolidated Sediment/Reef and Sand), and kelp coverage maps have been produced for the east coast of Tasmania. Large urchin barrens have been predicted and the minimum quantifiable unit of which small incipient barrens can be detected has been identified using this acoustic water column technique.This data provides a snapshot of the 2021 distribution of seafloor habitats and associated vegetation distribution, and will assist in the facilitation of strategic decision making for urchin control and abalone management.Data for download has been split by fishing block (22-24, 27-30). This record describes *FISHING BLOCK 27*. The following data products are available for download, for each fishing block:• 50cm resolution bathymetry• 50cm resolution substrate type (Seamap Australia classification)• bathymetry derivatives (seabed slope, curvature, rugosity, 1 and 2m contours)• water column data - 1m mean signal• water column data - 9m2 raw block statistic• water column data - vegetation likelihood classificationSee associated records for access to data from other fishing blocks (22, 23, 24, 28, 29, 30).

本项目的核心目标为借助多波束声呐成像（multibeam acoustic imagery）技术，绘制水深小于25米范围内受海胆影响的关键鲍鱼栖息地的精细空间分布格局。针对塔斯马尼亚东海岸，已生成详细的底质类型（substrate type）地图，涵盖硬质礁盘（Pavement Reef）、巨砾礁（Megaclast Reef）、混合固结沉积物/礁体以及沙质底四类底质，同时完成了海藻覆盖度制图。本研究采用该声学水体探测技术，实现了大型海胆荒礁（urchin barrens）的空间预测，并确定了可检出小型初期海胆荒礁的最小量化单元。本数据集呈现了2021年海底栖息地与相关植被分布的现状快照，可为海胆防控与鲍鱼资源管理的战略决策提供支撑。可下载的数据按捕捞区块（fishing block）划分为22-24、27-30共两组。本记录针对**捕捞区块27**进行说明。针对每个捕捞区块，可获取以下可下载数据产品：
• 分辨率达50厘米的水深测量数据（bathymetry）
• 分辨率达50厘米的底质类型数据（采用澳大利亚海图Seamap Australia分类标准）
• 水深衍生数据：包括海底坡度（seabed slope）、曲率（curvature）、粗糙度（rugosity）以及1米、2米等深线（contours）
• 水体柱数据（water column data）：1米平均信号值
• 水体柱数据：9平方米原始区块统计量
• 水体柱数据：植被可能性分类结果
可通过关联记录获取其余捕捞区块（22、23、24、28、29、30）的相关数据。