As part of the New Zealand government Ocean Survey 20/20 programme (OS 20/20, 2006–2013), samples from the Chatham Rise and Challenger Plateau collected in 2007 were analysed to determine the effects of key environmental parameters, in particular sediment and water mass properties, on spatial changes in the community structure (abundance, diversity and community composition) of bathyal asellotan isopods. Benthic collections were obtained in austral autumn (May/June 2007) and included a total of 21 epibenthic sledge samples taken from the upper slope between 218 and 1239 m. Due to the contrasting environmental settings between the Chatham Rise and Challenger Plateau, in terms of surface productivity and habitat heterogeneity, we expected the abundance, regional (or gamma-) diversity and community composition of benthic isopods to significantly differ between the two regions, and furthermore local (or alpha-) diversity and abundance (density) to decrease with increasing depth. Consistent with our assumptions, multivariate PERMANOVA analysis revealed a clear distinction in species composition between the Chatham Rise and Challenger Plateau with satellite surface chlorophyll (Chl) a and bottom temperature being the main environmental drivers. In contrast to previous benthic studies from the same sampling campaign, however, differences in isopod density and diversity between the two regions were not significant, either at species, or generic and family level. In addition, no depth-related changes in abundance and diversity could be observed at any hierarchical level. Instead, isopod densities at species and generic level were positively correlated with satellite surface Chl a and %silt, whilst species and generic diversity could be positively linked to the amount of total organic matter (TOM) in surficial sediments. In total, 97 asellote species in 54 genera and 15 families could be identified from both regions, of which 90.7% were likely new species. Species diversity was average to high when compared to other regions in the Northern and Southern hemispheres. However, neither for Chatham Rise nor for the Challenger Plateau did the species accumulation curves reach an asymptote, indicating that additional samples are required to provide more robust diversity estimates.

作为新西兰政府海洋20/20计划（OS 20 / 20，2006–2013）的一部分，分析了2007年查塔姆河谷和挑战者高原的样本，以确定关键环境参数的影响，特别是沉积物和的水质特性，取决于食盐性阿斯乐坦等足动物群落结构的空间变化（丰度，多样性和群落组成）。在南方秋季（2007年5月/ 2006年6月）获得了底栖动物的收集物，其中包括从218至1239 m之间的上坡采集的总共21个上栖动物的雪橇样本。由于Chatham Rise和Challenger Plateau之间的环境设置存在差异，因此在地表生产力和栖息地异质性方面，我们预计会有很多 底栖等足动物的区域（或γ-）多样性和群落组成在两个区域之间有显着差异，此外，局部（或α-）多样性和丰度（密度）随着深度的增加而降低。与我们的假设一致，多元PERMANOVA分析显示，在查塔姆河谷和挑战者高原之间，具有卫星表面叶绿素（Chl）的物种组成有明显区别a和底部温度是主要的环境驱动因素。但是，与之前来自同一采样活动的底栖生物研究相比，这两个区域的等足类动物密度和多样性差异在物种，属种或家族水平上均不显着。此外，在任何层次上都没有观察到深度相关的丰度和多样性变化。相反，在品种和仿制水平等足类密度呈正与卫星表面叶绿素相关一和％淤泥，而物种和通用多样性可能与表层沉积物中的总有机质（TOM）数量呈正相关。从这两个地区总共可以鉴定出54个属和15个科的97种亚种，其中90.7％可能是新种。与北半球和南半球的其他区域相比，物种多样性平均高。然而，对于查塔姆崛起和挑战者高原来说，物种积累曲线都没有达到渐近线，这表明需要更多样本才能提供更可靠的多样性估计。