“…Tests have been conducted in situ and ex situ, and researchers have compared effects of compaction, clay/sand proportions, clay type, organic content, pH, salinity, flora and fauna, and various other chemical and compositional parameters. In general, in situ flumes may be subdivided into two groups: (1) benthic re-circulating flumes (Amos et al, 1992;Black and Cramp, 1995;Houwing and van Rijn, 1998;Maa et al, 1993;Pierce et al, 1970;Widdows et al, 1998) and benthic straight flow-through flumes (Aberle et al, 2003;Gust and Morris, 1989;Ravens and Gschwend, 1999;Young, 1977), and (2) miscellaneous devices (Paterson, 1989;Schünemann and Kühl, 1993).…”