# The Suitability of Short Rotation Coppice Crops for Phytoremediation of Urban Soils
## 4 Conclusions  
Short rotation coppice phytoremediation was shown to be a promising method in an urban context to improve the landscape and to limit access to the contaminated area. All the tested plant genotypes showed good adaptation to the particular environment. _Robinia_ clones were demonstrated to be the most productive species in field conditions, probably due to the poor fertility of the soil, with respect to an agricultural soil, and to drought.  
Coppicing management modified the biomass relationships between roots, stem, and leaves. This, together with the differences in accumulation and translocation behavior of the genotypes, made evident the need, prior to a field trial, of a study to identify the management approach and suitable genotypes. Leaves contained a large part of the extracted PTE, thus a successful phytoremediation should include the collection of leaves, for example through the use of harvesting nets. _Poplar_ and _Salix_ species proved to be suitable for the field conditions (in particular clones P1, S1, and S3), diminished significantly the bioavailable concentrations of Zn in the soil. Conversely, in field conditions the 2-years of the project were not sufficient to diminish the total PTE concentration in the soil. Improving the biomass yield through phytomanagement options (fertilization, irrigation, coppicing, etc.) could make SRC phytoremediation an economic and effective solution to manage urban contaminated areas, coupling the added values of biomass production to the landscape benefits.  
**Supplementary Materials:** The Supplementary Materials are available online at [[http://www.mdpi.com/2076-3417/10/1/307/s1](http://www.mdpi.com/2076-3417/10/1/307/s1)]([http://www.mdpi.com/2076-3417/10/1/307/s1](http://www.mdpi.com/2076-3417/10/1/307/s1)), Table S1 Table S1. Coefficient of the equation to estimate aboveground biomass per tree (DW) in g from diameter at 10 cm of height (D10) in the first and second year of growth, Table S2: Table S2. Survival percentage (Sur), number of sprouts per stump (ns/s) and stem dry biomass yield at the end of first year in Mg per hectare, per genotypes and turnover coppicing, Table S3: Table S3. Survival percentage (Sur), number of sprouts per stump (ns/s) and stem dry biomass yield at the end of second year (B1+2) in Mg per hectare, per genotypes and turnover coppicing, Table S4: Table S4. Mean total trace element concentrations in leaves, stem, and roots of the nine cultivars for both harvesting seasons, Table S5: Table S5. Average Zn and Cu phytoextracted (calculated as g ha\({}^{-1}\)) and distribution among aboveground and belowground tissues, Table S6: Table S6. Ground water analysis, piezometers PV1 and PV2; Figure S1. Photo of the area before the remediation process and at the end of the first vegetative season.  
**Author Contributions:** [PERSON]-[PERSON], [PERSON], and [PERSON] developed the concept of the work. [PERSON]-[PERSON], [PERSON], and [PERSON] designed the methodology. [PERSON], [PERSON], [PERSON], and [PERSON] sampled and analyzed the samples. [PERSON] and [PERSON] wrote the manuscript. [PERSON], [PERSON], and [PERSON] reviewed and edited the manuscript. All authors have read and agreed to the published version of the manuscript All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research was funded from the Turin City Council, under the contract \"Progetto per applicazione di tecniche di phytoremediation su area all'interno del Parco Dora, zona Spina 3\".  
**Conflicts of Interest:** The authors declare no conflict of interest.