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Biochar has been widely proposed as a habitat for soil microorganisms.This preliminary study explored imaging techniques to visualize and quantify microbial colonisation associated with biochar habitable spaces and microenvironment.In addition to characterisation of biochar,there was a need to optimise preparation and observation methodologies for examining microbial colonisation of biochar.Microbial colonisation of biochar surfaces and pores was investigated using several microscopy techniques.Biochar particles were experimentally prepared and compared in soilless media and following deposition in soil.Light, fluorescence and electron microscopy were employed for microscopic observation of biochar as a habitat for soil microorganisms.Visualization of fungal hyphal networks associated with biochar stained by fluorescent brightener RR 2200 was effective and this was validated using scanning electron microscopy (SEM).However, both the observation and quantification of microorganisms on the surfaces and in pores of biochar were difficult due to limitations of two-dimensional (2D) imaging associated with uneven biochar surfaces and biochar pore structure.Hyphal colonisation of biochar incubated in soil was much less than in soilless media.Observation of biochar particles colonised by microorganisms in soil posed a range of difficulties including obstruction by the presence of soil particles on biochar surfaces and in pores.This investigation highlights the need for a multi-scale approach and the importance of 3-dimensional observations to extend understanding of how biochar particles and its microenvironment provide habitat for soil microorganisms, especially under field soil conditions.