Fig. 13. Number of seedlings 30 and 60 d after seeding in the sand, clay, coal discard, and gold tailings media treated with 60 Mg kg-1 water treatment sludge.
Fig. 13. Number of seedlings 30 and 60 d after seeding in the sand, clay, coal discard, and gold tailings media treated with 60 Mg kg-1 water treatment sludge.