Page 157 - Plant-Based Remediation Processes

148 T. Vamerali et al.

Fig. 8.3 Metal concentrations (mg kg 1 DW) in shoots of various spontaneous herbs (above) and
wood of trees (below) collected at pyrite-contaminated site, sorted by root system type and
botanical family. Herbs studied: Carex hirta L., Sanguisorba officinalis L., Calamagrostis sp.,
Cynodon dactylon (L.) Pers., Dactylis glomerata L., Festuca arundinacea Schreb., Holcus lanatus
L., Phragmites australis (Cav.) Trin., Poa pratensis L., Ambrosia artemisiifolia L., Eupatorium
cannabium L., Taraxacum officinale Weber., Medicago lupolina L., Melilotus album Desr. Other
elements: As + Cd + Co + Cr + Ni + Pb

Setting up the phytoremediation plant at Torviscosa in 2005 gave us the oppor-
tunity of testing various soil management strategies, by comparing unaltered
stratigraphy with mixed layers, i.e., ripping vs. ploughing tillages, both at a depth
of 0.3 m. Ploughing entailed more thorough mixing of soil than ripping, which
simply broke up the surface. Ploughing was intended to dilute the waste with the
unpolluted top soil, and ripping to allow roots to encounter a clean habitat, at least