TY - JOUR N2 - This study applied a modified OxiTop® system to determine the oxygen uptake rate during a 2-day respiration test of selected composting materials at different moisture contents, air-filled porosities and composition of composting mixtures. The modification of the OxiTop® respirometer included replacement and adjustment of a glass vessel (i.e. a 1.9-L glass vessel with wide mouth was used instead of a standard 1-L glass bottle, additionally the twist-off vessel lid was adjusted to attach the measuring head) and application of a closed steel mesh cylinder of 5 cm in diameter and 10 cm in height with the open surface area of the mesh of approximately 56.2%. This modification allowed obtaining different bulk densities (and thus air-porosities) of the investigated composting materials in laboratory composting studies. The test was performed for apple pomace and composting mixtures of apple pomace with wood chips at ratios of 1:0.5, 1:1, 1:1.5 (d.w), moisture contents of 60%, 65% and 75% and air-filled porosities ranging from 46% to 1%. Due to diverse biodegradability of the investigated apple pomace and composting mixtures this test allows for the determination of the effects of different air-porosities (due to compaction in a pile) on the oxygen uptake rate for mixtures with a fixed ratio of a bulking agent. The described method allows for laboratory determination of the effects of moisture content and compaction on biodegradation dynamics during composting. L1 - http://journals.pan.pl/Content/86137/PDF/aep-2016-0007.pdf L2 - http://journals.pan.pl/Content/86137 PY - 2016 IS - No 1 DO - 10.1515/aep-2016-0007 KW - respiration tests KW - oxygen respiration rate KW - pressure drop method KW - OxiTop® respirometer KW - Composting KW - biodegradation A1 - Malińska, Krystyna PB - Polish Academy of Sciences VL - vol. 42 DA - 2016.01.01 T1 - Application of a modified OxiTop® respirometer for laboratory composting studies UR - http://journals.pan.pl/dlibra/publication/edition/86137 T2 - Archives of Environmental Protection ER -