Joint International Conference on Long-term Experiments ...

COMPOSTED SLAUGHTERHOUSE BY-PRODUCTS EFFECT
ON CROP YIELD
Péter Ragályi, Imre Kádár
Research Institute for Soil Science and Agricultural Chemistry
H-1022, Budapest, Herman Ottó Str. 15, Hungary. E-mail: ragalyi@rissac.hu
ABSTRACT
Use of treated slaughterhouse waste as fertilizer can be a good way to maintain soil
productivity as well as reduce organic waste. Effect and residual effect of different
composts and meat powder were examined on crop development and yield on a
calcareous sandy soil. The soil contained 1-6% CaCO3 and 1-1.5% humus, humus layer
was 60-80 cm and pH(H2O) 7.0-7.4 as an average. The site had a poor N, P and K
supply. Water table was at 6-8 m depth. Trials were set in 2002 and 2003 with 5 doses
(0, 25, 50, 100, 200 t/ha fresh compost and 0; 2,5; 5; 10; 20 t/ha meat powder once
applied) and 4 replications giving a sum of 20 plots with 5x8=40 m 2 area each, arranged
in split-plot design. Sown crops were maize in 2002, mustard in 2003 and triticale
monoculture from 2004.
In the first two years of the trial the yield was negligible due to draught, though
tendencies showed 50t/ha dose mature compost and 25 t/ha immature compost as
optimal treatment.
All of the composts had significant residual effect on triticale in 2004 as the weather
was favourable and immature compost increased harvested straw and grain air-dried
yield from 1.6 to 5.3 t/ha. Maximal yields occurred at the maximal compost doses
without depression. In following years residual effects were moderated, but differences
were significant in the case of stronger composts even in 2006, in the 4 th and 5 th
experimental years.
Keywords: compost, fertilization, crop yield, slaughterhouse by-product
INTRODUCTION
Fodder use of animal origin wastes is strictly regulated by EU since BSE (bovine
spongiform encephalopathy) disease showed up, so alternative utilities have to be
found. In Hungary 100-120 million tons of wastes produced of which 5% is so called
“hazardous”. Hazardous wastes from animal bodies reach 300-400 thousand tons of
which 70-90 thousand are composted. After heat treatment these wastes become nonhazardous,
and other treatments like composting make land application possible. This
practice may improve soil parameters like organic matter, nutrient content, water
holding capacity and also reduces the yearly deposited 55 000 tons of slaughterhouse
wastes and sewage sludge (Vermes 1998, Kiss et al. 2001). Burying or incineration of
these materials is expensive and can result in environmental pollution (Izsáki 2000).
Debreczeni and Izsáki (1985) set up pot experiments to study the changes of field crops
grown on calcareous sandy soil and chernozem meadow clayey soil mixed with various
doses of sewage sludge from a tannery. On calcareous sandy soil 13 g sludge D.M. / kg
soil increased mustard above ground parts with 74% but higher doses caused
depression. Maize yields (above ground) were doubled in 33 g sludge D.M. / kg soil
239