The effect of soil organic matter amount on mineral nitrogen content in soils

The aim of this thesis was to determine the effect of soil organic matter content on soil mineral nitrogen in Çukurova Region. In the study, mineral nitrogen (Nmin) values were calculated by measuring NH4+ and NO3- using samples taken from three different soil depths (0-30, 30-60 and 60-90 cm) after the harvest period in 2017. In addition, the organic matter (OM), soil texture, total nitrogen, electrical conductivity (EC), pH, calcium carbonate of the soils were also measured, and their effects on soil mineral nitrogen were evaluated. The relationships between the soil OM content and the N forms in the soil (total N, NO3--N, NH4+-N, Nmin, organic N) are examined; It is determined that the OM content of the study area varies between %0.49 and %3.33 and the soil N content varies accordingly. Due to the low OM content of the soils, sufficient N may not be supplied to the soil; for a sustainable crop production, N fertilization is necessary. In conclusion, it has been determined that soil OM content has a relationship with soil N content as well as its effects on soil fertility. Therefore, for a sustainable and environmentally sound crop production, it is necessary to increase the soil OM content (such as organic fertilization and incorporating the harvest residues into the soil). Keywords: Soil Organic Matter, Soil Mineral Nitrogen, Nitrogen Forms in Soils