Fig. 3From: Structure and predictive functional profiling of microbial communities in two biotrickling filters treated with continuous/discontinuous waste gasesPrincipal coordinate analysis (PCoA) of microbial communities. Samples collected from the bottom layer and upper layer are labeled by letter respectively. First number denote BTF1 or BTF2. Last two numbers indicates the sampling day. Sample from initial inoculums are showed with black circles, and sample from recycling nutrient showed with blue circlesBack to article page