While this is for D09 (very late) -  it is very specifically related to the effect of pH rather than a much broader baseline characterisation of the microbial communities, and I appreciate that I am coming to this after an absence but wonder why he chose to do this. Especially as there is reference to the fact that this work doesn't reveal anything new. I am also left wondering what the impact this work has on the overall objective of the project..... Please ignore if none of this is appropriate at this stage.

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