Nella Dan: ADBEX II Cruise - Hydroacoustic krill survey data

This dataset contains hydroacoustic results from the Antarctic Division Biomass Experiment II (ADBEX II) cruise of the Nella Dan. This cruise is the third in a series of six cruises, performing a long term survey of krill and other zooplankton distribution and abundance.

Australia was to have participated in the Second International Biomass Experiment I (SIBEX I), but withdrew due to resupply problems. ADBEX II is a reduced sampling program of what was to have been sampled during SIBEX I. Three transects were made off Antarctica in the Mawson region of the Australian sector, in January to March 1984, covering a survey area of 70,000 square kilometers. Quantitative and geographic krill distribution, abundance, mean and variance of the krill weight density, and total krill biomass were obtained. Biomass estimates for ADBEX II are given as 3.5 million tonnes, obtained by extrapolating over the survey area used on the SIBEX II cruise (1.28x10^6 square kilometers). Temperature, nutrient and salinty data were also obtained, as well as trawl results. Summary results are listed in the documentation.

The fields in this dataset are:
pressure
temperature
salinity
volume
geopotential
samples
deviation

本数据集包含"内拉·丹号"（Nella Dan）科考船执行的澳大利亚南极局生物量实验II（ADBEX II）航次的水声探测结果。该航次为6个系列航次中的第三个，旨在长期调查磷虾及其他浮游动物的分布与丰度。

澳大利亚原本计划参与第二届国际生物量实验I（SIBEX I），但因补给保障问题退出。ADBEX II是原计划在SIBEX I中开展的采样项目的缩减版本。1984年1月至3月，科考团队在澳大利亚南极辖区的莫森海域南极近海完成了3条断面测线，覆盖调查面积7万平方千米。研究获取了磷虾的定量与地理分布特征、丰度、磷虾体重密度的均值与方差，以及总磷虾生物量。通过在SIBEX II航次使用的调查区域（1.28×10^6平方千米）上外推计算，ADBEX II的生物量估算值为350万吨。此外，本数据集还包含温度、营养盐与盐度数据，以及拖网采样结果。相关汇总结果已整理于配套文档中。

本数据集包含以下字段：
pressure（压强）、temperature（温度）、salinity（盐度）、volume（体积）、geopotential（位势）、samples（采样样本数）、deviation（偏差）