First, identify the target organisms and ecosystem, then apply appropriate sampling technique. Plant or animal; pelagic or benthic; micro- or macro-; migratory or resident, etc? Bio-indicator of what? Pollution? I do not think there is just one sampling technique suitable for all types.
@Francis Nwosu bio indicator of pollution organisms, thanks so much for your suggestion and @ Tomas (Tom) Tomascik, thanks so much for the materials, it really help.....