The bottom Sampler-a new technique for sampling bed sediments in streams and lakes

摘要

New,easy to use,liquid nitrogen-cooled equipment is described for sampling upper layer (80-160 mm) of water sediment and associated benthic organisms in streams and lakes up to 1.2 m deep.The sediment sample has an area of 0.0531 m~2 and retains its natural composition and spatial strucure.The two sampler components weight 15 kg in total,which enables sampler use by hand,even in rural areas that are not readily accessible.A successful 2-year testing period in several first and second orderstreams demosntrated the suitability of the apparatus for samplign sediment textures rangign from fine clay to cobbles and current velocities up to 1 m s~-1.