highly significantp = 0.0012
Despite this, the eliminations in this study ( Figure 4 a,b) were highly significant ( p = 0.0012): in a system with three plants the removal on average was 79 and 80%; in systems with six plants 80 and 82%; in systems with nine plants 61 and 64%, and in controls without vegetation 84 and 90% in PET and PRS substrate respectively.