Spatiotemporal variability of epibenthic assemblages in Moreton Bay

Raw data on the abundance and percentage cover of epibenthic taxa identified during surveys in Moreton Bay from 1998-2002 and 2012-2015. Surveys were taken using underwater videography at a total of 63 sites and used to determine where and how epibenthic assemblage structure had changed from 1998 to 2015. <br>Original surveys were taken from 1998-2002 for a habitat mapping study (Stevens &amp; Connolly 2004). Resurveys of a subset of sites were taken from 2012-2014 by a study conducted for the Queensland Department of Science, Information, Technology, Innovation and the Arts (Stevens &amp; Richmond 2014). Re-surveys of the remaining sites that had not yet been revisited were taken in 2015 and were combined with the 2012-2014 data, for comparison with the 1998-2002 data.<br>From each survey a total of 50 still images were extracted at 5 second intervals, and the abundance or percentage cover of each identifiable organism was determined. These values were then divided by 50 to obtain the relative abundance and percentage cover of each species per site. This data was then incorporated into Primer E (v.6) for analysis.<br>The relative influence of abiotic variables on assemblage structure was determined using long term data on sediment mud content (O'Brien, Tuazon et al. 2012) and on other abiotic variables such as sea surface temperature, turbidity and nutrient content (made available from the Healthy Waterways Ecosystem Health and Monitoring Program).

本数据集为1998-2002年及2012-2015年在莫顿湾（Moreton Bay）调查中鉴定得到的底栖表生生物类群（epibenthic taxa）丰度与盖度百分比原始数据。本次调查采用水下摄像技术，共覆盖63个采样点，旨在明确1998年至2015年间底栖表生生物群落结构的空间分布与变化模式。
初始调查于1998-2002年间开展，用于一项生境制图研究（Stevens与Connolly，2004）。2012-2014年，昆士兰州科学、信息、技术、创新与艺术部主导的一项研究对部分采样点进行了重采样（Stevens与Richmond，2014）。2015年，研究人员对剩余未被重访的采样点开展补测，并将2012-2014年的采样数据与之整合，以与1998-2002年的初始调查数据进行对比分析。
每次调查均以5秒为间隔提取50张静态图像，进而确定每种可识别生物的丰度与盖度百分比。随后将各项数值除以50，得到每个采样点各物种种群的相对丰度与盖度百分比。最终将该数据导入Primer E（v.6）中开展分析。
研究基于沉积物泥质含量的长期监测数据（O'Brien、Tuazon等，2012）及海表温度、浊度、营养盐含量等其他非生物变量数据（由健康水道生态系统健康与监测计划提供），分析了非生物变量对底栖表生生物群落结构的相对影响程度。