Browsing by Author "Tammeorg, Priit"

Meat and bone meal (MBM) is a valuable co-product of the rendering industry. Its feed and fertilizer uses were restricted in the EU in 2002 as a result of the occurrence of BSE crisis. Consequently, MBM was land filled, incinerated or used as an alternative fuel in cement production. The re-allowance of the fertilizer use of MBM in the EU since spring 2006 together with the rising prices of industrial nitrogen and phosphorus fertilizers have resulted in amplified research and use of MBM as a fertilizer. Additionally, growing consciousness of both finiteness of resources and deteriorating environmental effects of the artificial fertilizer use have contributed to growing popularity of nutrient recycling. The fertilizer effect and the nutrient uptake efficiencies of the Finnish MBM (N-P-K-Ca 8–6-0.5-15%) compared to mineral counterparts were tested for in present study. Additionally, the fertilizer effect of MBM in mixture with two potassium fertilizers was tested for. A greenhouse experiment with ryegrass (Lolium multiflorum) fertilized with five fertilizers (MBM, mineral fertilizers Y4PK and NK, two mixtures of MBM and potassium fertilizers) was conducted from 2007 to 2008 in Department of Agricultural Sciences greenhouses in University of Helsinki, Finland. Each of the fertilizers was applied on three nitrogen levels (80, 160 and 240 kg N ha-1). Four additional reference treatments (0 kg N ha-1 fertilizer, PK I, PK II and PK III) were included. Six cuts of ryegrass were cut and the yields were recorded. Post-harvest plant and soil analyses were conducted. MBM was shown to be a highly effective N and P fertilizer with fertilizer effect similar or even longer lasting than artificial Y4PK fertilizer. Additionally, unlike highest application levels of mineral fertilizer Y4PK and NK, meat and bone meal treatments did not lower the pH level of the soil. Therefore, it can be concluded that the relatively high Ca content of MBM is useful in preventing further costs for liming the soil. The nutrient uptake efficiencies of MBM were generally somewhat lower than for mineral counterparts. That could be partly attributable to possible immobilization of MBM-N to soil and partly to lower readily plant-available P content of MBM than mineral fertilizers. However, as significant amount of MBM-P is still available for following years, it is justified to use MBM only once in a crop rotation. That makes MBM an especially effective complementary N and P fertilizer for organic farming, where most of the nitrogen need in crop rotation is covered with legumes and manure. The fertilizing potential for mixture of MBM and K fertilizers was shown to be rather high. However, the lack of affordable potassium sources suitable for organic farming is a recognized challenge. Additional research is needed for convalescing MBM as NPK fertilizer.