Search Results (2)

Modern hydroponic substrates have contributed significantly to the popularity and progress of hydroponic cultivations worldwide, nevertheless, their development, transportation, and disposal often come at a significant environmental cost. Here we investigate the feasibility of partial to total replacement of conventional organic growing media constituents, such as cocodust (C), in a 20% perlite (P) and 80% cocodust substrate (hereafter control 8C), with compost from locally sourced grocery waste (W). For this purpose, four treatment mixtures were developed (6C:2W, 4C:4W, 2C:6W, 8W), with the grocery waste-compost fraction ranging from 20 to 80%, respectively (perlite constant at 20%). The new substrates were tested on hydroponic lettuce (Lactuca sativa var. Tanius) cultivation. During the 35-day experiment, lettuce physiology was evaluated using chlorophyll concentration [SPAD], chlorophyll fluorescence [Fv/Fm], number of leaves, and plant growth index. At harvest, the plant yield was evaluated using leaf area [cm²], leaf fresh and dry weight [g], as well as leaf firmness [g]. Results show that substrates with compost led to superior physiology and yield characteristics, with 8W inducing a significant increase in leaf area, chlorophyll concentration, dry weight, and firmness, by 11.6%, 5.4%, 19.8% and 12.8%, respectively, compared to the control treatment 8C. Results indicate that grocery waste-based compost is an excellent sustainable alternative for the soilless cultivation of lettuce. After its use in hydroponic cultivation, substrate material is safe to dispose of or be used as a soil amendment, thus contributing to a circular agro-food economy model. Full article

In recent years biodegradable plastic films have been increasingly used for various purposes, most often as grocery bags and for collecting bio-waste. Typically, the biodegradation of these films should take place in industrial compost facilities where the biodegradation process occurs under controlled conditions. Nevertheless, many of these films are often disposed of in home composting bins, so the aim of this study was to examine the course of biodegradation of compostable plastic films under uncontrolled conditions in garden composting sites during a period of four months. Mechanical properties were tested on seven different commercially available biodegradable films and bags that were placed in a garden composting bin from February to May. Both tensile properties and tensile-impact strength showed some unexpected results in terms of increase of the properties after the first, second, and third month for some films and bags. The same unpredictability was seen in FTIR and TG analyses. Full article