Considerable research has been conducted on the fate of nutrients in compost-amended agricultural soils, but minimal information is available on the use of turfgrass for compost application and subsequent effects on soil organic matter and
(Florida Exotic Pest Plant Council, 2013). Composting is a biomechanical process during which microorganisms such as bacteria and fungi convert organic matter into a waste-free, soil-like product ( Epstein, 1997 ; Rynk, 1992 ). The mechanical manipulation
Compost applications alone or in combination with cultural practices or chemicals have the potential to contribute to the control of root pathogens ( Mazzola et al., 2006 ; Peryea and Covey, 1989 ; van Bruggen, 1995 ; Zinati, 2005 ). ARD is a
sought to identify alternatives to peat, focusing on renewable, locally available and low-cost materials derived from renewable and local available low-cost sources. Several waste materials can be successfully used, after composting, as alternative
walks” as impeding beach enjoyment ( Williams et al., 2015 ). Composting is a biomechanical process during which microorganisms such as bacteria and fungi convert organic matter (OM) and “waste” materials into a soil-like product called compost ( Rynk
82 COLLOQUIUM 3 Municipal Waste Compost Production and Uses for Horticultural Crops
Application of organic amendments can increase dissolved organic C (DOC) concentrations, which may influence movement of nutrients and heavy metals in soils. The objectives of this study were to investigate the influence of compost sources and application rates on concentrations of soil DOC, NO3-N, and extractable P over 29 months after a one-time application of compost to bermudagrass [Cynodon dactylon (L.) Pers.] turf. Few differences were evident between compost sources for soil total organic C (TOC), DOC, and NO3-N. However, the initial P content of compost sources significantly influenced soil extractable P. Increasing the rate of compost application increased soil TOC initially, but levels remained fairly stable over time. In contrast, DOC continued to increase from 3 to 29 months after application, suggesting that compost mineralization and growth of bermudagrass contributed to DOC dynamics in soil. Dissolved organic C was 98%, 128%, 145%, 175%, and 179% greater 29 months after application of 0, 40, 80, 120, and 160 Mg compost/ha, respectively, than before application. Rate of compost application had less effect on DOC than TOC, as DOC concentrations appeared controlled in part by bermudagrass growth patterns. Soil NO3-N was generally unaffected by compost application rate, as NO3-N decreased similarly for unamended soil and all compost treatments. Soil extractable P initially increased after compost application, but increasing the application rate generally did not increase P from 3 to 29 months. Seasonal or cyclical patterns of TOC, DOC, and extractable P were observed, as significantly lower levels of these parameters were observed in dormant stages of bermudagrass growth during cooler months.
led researchers to test the possibility of composting this material to use it as a horticultural substrate in place of peat ( Castaldi and Melis, 2004 ). Recently, some attempts have been made to use Posidonia deposits as growing media in soilless
Commercial citrus (Citrus sp.) groves in Florida use an average of 150 lb/acre (168 kg·ha-1) of elemental nitrogen (N) per year. There are about 853,000 acres (345,000 ha) of commercial citrus requiring about 63,975 tons (62,652 t) of N. At an average analysis of 12% N, about 533,125 tons (483,811 t) of blended nitrogenous fertilizers are applied to citrus annually. To meet this annual N demand from compost, it would be necessary to produce 3,198,750 tons (2,901,906 t) of 2% N compost. The market for high-quality compost products in Florida is far greater than the current or projected production capacity of the state. As long as the cost benefits of compost are clear to citrus growers, demand will always exceed supply. Not all composts are equal in their nutrient availability. The best composts for use as fertilizers are derived from sewage sludge or biosolids, municipal solid waste and sludge, food waste, and/or animal manure combined with a bulking agent such as sawdust or wood chips. Composts made from wood waste as their only feedstock contain large amounts of lignin and cellulose to break down within a reasonable period to directly offset chemical fertilizers. Ultimately, they will mineralize in the soil and provide all of the benefits described earlier, but their rates of availability are in years rather than months, like the other composts.
82 COLLOQUIUM 3 Municipal Waste Compost Production and Uses for Horticultural Crops