Long-term effect of soil management on the carbon-dioxide emission of the soil

CO2 emission from soils is one of the most important elements of the global carbon cycle, thus it has crucial rule in climate change. Each soil cultivation operation intervenes in the microbiological life of the soil, hence tillage is a factor through that the processes taking place in soil can be controlled. During the last decades, the organic material content of agricultural soils decreased to the half due to the intensive management resulting in the degradation of natural soil fertility. While intensive, plough-based tillage can cause soil degradation and erosion, the physical, chemical and biological status of the soil can be significantly improved through the application of conservation tillage methods. The results of long-term experiments prove that soil protective tillage enhances the  enrichment of organic matter in the top layer of the soil. In order to reveal the role of tillage systems in CO2 emission from the soil,  regular measurements were carried out in the plots with conventional and reduced tillage of the soil cultivation experiment of Research Institute of Karcag. Anagas CD 98 and Gas Alert Micro 5w infrared gas analysers were used to measure CO2-concentrations, and a specially developed method (consisting of a frame and a bowl) was applied to delimitate the measuring area. Most of the  measurements were done on stubbles after harvest in order to exclude root respiration. The weather conditions of the examined 10 years were very changeable providing a good chance to compare them to each other. We found the tillage operations resulting in  higher emission values in both tillage systems. On stubbles higher and more even emission was characteristic to reduced tillage due to the lower degree of soil disturbance and higher soil moisture content.