SRE4 (Sediment Recruitment Experiment 4) Sediment grain size analysis, Casey Station, 2001-2006

Sediment Recruitment Experiment 4 (SRE4) was a large, long term (5 year) field experiment run at Casey Station (from 2001 to 2006) testing the effects of 4 different hydrocarbons on marine sediment ecosystems. Four different types of hydrocarbons were individually mixed with defaunated marine sediments and deployed in trays on the seabed at O'Brien Bay-1. Trays were collected after deployment periods of 5 weeks, 56 weeks, 62 weeks, 2 years and 5 years. In addition there was a bioturbation treatment using the burrowing urchin Abatus (at 56 weeks only). Samples were collected from 4 replicate trays of each treatment at each sampling time. Analyses were done of sediment hydrocarbon chemistry, microbial communities, meiofaunal communities, macrofaunal communities and diatom communities. The hydrocarbon treatments were: a synthetic Mobil lubricating oil; the same Mobil lubricating oil after 125? hours use in a vehicle engine; a Fuchs synthetic lubricating oil marketed as highly biodegradable; and Special Antarctic Blend diesel fuel (SAB). A control uncontaminated sediment treatment was used for comparison.

沉积物招募实验4（SRE4）是一项大型长期（为期5年）的野外实验，于2001年至2006年间在凯西站（Casey Station）开展，旨在探究4种不同烃类物质对海洋沉积物生态系统的影响。实验将4种不同的烃类物质分别与脱除动物群落的海洋沉积物混合，随后放置于奥布莱恩湾1号站位（O'Brien Bay-1）海床的托盘内。分别于部署后5周、56周、62周、2年及5年时回收托盘样品。此外还设置了生物扰动处理组：采用穴居海胆属（Abatus）物种进行扰动，该处理仅在第56周采样时实施。每次采样时，均从各处理组的4个重复托盘中采集样品。实验针对沉积物的烃类化学组成、微生物群落、小型底栖动物群落、大型底栖动物群落以及硅藻群落开展了检测分析。本次实验设置的烃类处理组包括：① 美孚（Mobil）合成润滑油；② 经车辆发动机运转125小时后的同款美孚合成润滑油；③ 福斯（Fuchs）一款宣传为高生物降解性的合成润滑油；④ 南极专用混合柴油（Special Antarctic Blend diesel fuel，简称SAB）。同时设置未受污染的沉积物对照组以作为参照。