Natalia, YessiItnawitaHanifah, T. Abu2017-01-062017-01-062017-01-06http://repository.unri.ac.id/xmlui/handle/123456789/8852The different frequencies of fires on palm soil in the Pakning Asal of Bengkalis could change structures and component of nutrients inside of the soil as total of calcium, magnesium, sulphate and C/N. The analys were conducted on the soil with once on fire, several times burned and no burn in the last five years. The total content of calcium and magnesium was determined by using complexometry titration method, a total of sulphate was determined by turbidimetry method and the C/N was determined by visible spectrophotometry method that for carbon, while for total of nitrogen was determined using the method Kjeldahl. Based on the results in this research, the fires could change the content of calcium and magnesium in total from the soil without fire to several times burned, are increased from 0,217 – 0,371% and 0,095 – 0,137%. The total sulphate in the soil wihout fire 0,481% increased to 0,509% on the soil with once burned and decreased to 0,118% on the soil often burned. The C/N also increased from 16,580 – 25,393 with increasing frequency of fires.otherBurned soilcomplexometry methodKjeldahl methodspectrophotometrystudent Paper Post Degree