Substance release of waste rubber granules in extraction solution and effects of seed soaking with the extract on turfgrass growth
废橡胶颗粒浸提液物质释放及其浸种对草坪植物生长的影响

By the method of inductively coupled plasma-atomic emission spectrometer (ICP-AES), this paper determined the Cu, Zn, Cd and Pb concentrations in extraction solutions of waste rubber granules and their mixture with soil. The results showed that the Zn concentration in rubber granules extract was the highest, followed by Pb, and Cd and Cu. Compared with that of rubber granules, the extract of the mixture had an obviously decreased Zn concentration. Ultraviolet absorption spectrum suggested that the smaller the rubber granular size, the more complicated the organic substances in the extracts. The seed soaking experiment with two turfgrass species seeds and four granular size rubber extracts showed that the extracts had little effects on seed germination, but definite effects on plant height growth. For Lolium perenne, the plant height was the highest (8.99 cm) after seed soaking with 2-4 mm granules extract, followed by that after treated with 1-2 mm and 4-6 mm granules extracts, being 1.52 cm and 1.32 cm shorter, respectively, but had no significant difference with the control. For Festuca arundinacea, the plant height was the lowest (7.06 cm) after seed soaking with 1-2 mm granules extract, which was decreased by 18.76% as compared with the control, but no significant difference was observed among other treatments. Seed soaking decreased the underground biomass but promoted the root length growth of L. perenne, while little effects were detected on the underground biomass and root length growth of F. arundinacea as well as the aboveground biomass of the two turfgrass species. It was concluded that waste rubber granules could be safely applied as a medium amendment for sports turf.