ABSTRACT
Th e shortage of simple in situ techniques with which to study environmental biofilms has resulted in the present lack of quantitative data on the architecture and function of these microbial structures, even though they play vital roles in water quality, wastewater treatment and industrial biofouling. Thin sectioning is widely performed on many biological specimens to permit visualization of microscopic structure within macroscopic samples. This ap proach however, is generally applied to tissues that are easily handled, rather than delicate surface layers such as biofilm. Although cryosectioning method ologies have previously been applied to artificial biofilm, the technique had been shown to be unsuitable for many environmental biofilms because of the more heterogeneous composition of natural biofilms and their substrata (Huang et al., 1996).
