Monitoring and validation of the use of remediated sediments as a substrate for nursing and cultivation: food crop production". "Physical, chemical and biochemical properties of the growing media". Deliverable action C.3.3:

The sediments constitute a very difficult substrate to insert in agronomic and horticultural contexts due to their geomorphological characteristics and contamination, in particular, the bulk density, the clay component and the generally low carbon content constitute qualities that make their use in these context difficult. In the Subsed project, various percentages of the recovered sediment were tested in specific growth substrates for each type of cultivated species. The substrates were chemically, physically, and biologically characterized at the time of their preparation and after the growth of the plant species of interest. Specifically, these substrates have been used for the growth of Ocimum basilicum (basil), Fragaria vesca L. (wild strawberry), Vaccinium corymbosum L. (blueberry), Grafted Olea europaea L. (olive), Citrus limon L (citrus) and Citrus limon L (citrus) seedling rootstocks. The improvement of the physical and chemical properties of the substrates, in line with Italian legislation (D.lgs. 75/210), already occurred with the addition of 25% of coconut. As seen previously, the plant uptake further reduced the heavy metal concentration, that were in line with the law limits, except for Zn and Cu due to the chemical treatments applied. The release of plant exudates and remains could have affected the total nitrogen and total organic carbon over time, especially in 50% and 25% of sediment. In addition, the plant activity influenced the enzymatic activities that increased during the plant growth, as seen previously. The measurement of plant growth and physiology will indicate if the substrate differences have led to a different plant response.