Carbon dioxide and methane gases are greenhouse gases produced both naturally and through human activity. As the greenhouse effect is generally regarded as a long-term environmental problem, sources of greenhouse gas emissions are of general interest and especially those from human activity.
This experiment was designed to investigate probable carbon dioxide emissions and possible methane gas emissions from a simulated compost in a respirometer in a laboratory. The results, however, were not accurate and possible explanations for why this is the case are explored and discussed.
A compost sample was designed, manufactured, and placed in a respirometer. Air was passed through the vessel and samples of the effluent air were analysed by a gas chromatograph specifically set-up to detect carbon dioxide (CO2) and methane (CH4) concentrations. In this experiment, the carbon dioxide levels detected were lower than the concentration of carbon dioxide present in the atmosphere (levels detected were around half of that of air) which points to obvious large errors. The results are therefore inconclusive.
There are a number of improvements which could be made to the design for this experiment if it is repeated in the future. These improvements include incorporating prepared natural compost within the sample to introduce organisms which occur naturally in backyard compost heaps and incorporating analysis of the gas chromatograph calibration before the experiment begins.