Abstract:In order to study the influence of cement dust on the magnetic properties of farmland soil, two perennial flipping typical paddy soil profiles (L01, L02) and one hilly area soil profile (L04) were excavated around the cement plant, and a reference profile (L03) was excavated at the same time. Environmental magnetic analysis method was employed and the magnetic parameters, mineral composition and chemical composition of the 4 soil profiles were measured. The feasibility of using magnetic parameters to indicate the pollution of cement dust to paddy soil around industrial area was discussed. Results showed that the main minerals in the 3 soil profiles around the cement plant were quartz, illite, goethite, montmorillonite and calcite. Ferrimagnetic minerals and antiferromagnetic minerals existed in the paddy soil profiles, but the contents were relatively low, the average values of mass susceptibility (χ), anhysteretic remanent susceptibility (χARM) and saturation isothermal remanent magnetization (SIRM) were 12.05×10-8 m3/kg, 52.71×10-8 m3/kg, 9.74×10-4 Am2/kg for profile L01 and 9.40×10-8 m3/kg, 43.82×10-8 m3/kg, 7.67×10-4 Am2/kg for profile L02, respectively. The magnetic mineral particle size in the 2 profiles became coarser, and the content of super-paramagnetic particles was relatively lower, the average values of 2 profiles' frequency susceptibility (χfd) were 3.41% and 3.08%, respectively. The content of ferromagnetic minerals in the hilly area soil profile L04 was very high, the average values of χ, χARM and SIRM were 53.85×10-8 m3/kg, 393.73×10-8 m3/kg and 26.90×10-4 Am2/kg, respectively. The magnetic mineral particle size in this profile was fine, the content of super-paramagnetic particles was very high, and the average value of χfd was 14.20%. Because of the influence of cement dust, the magnetic properties and ωCaO of 0-20 cm soil in the 3 soil profiles (L01, L02, L04) around the cement plant had been obviously changed, magnetism enhanced, magnetic particle size became coarser, ωCaO increased. ωCaO was significantly positively correlated with magnetic parameters χ, χARM and SIRM. In conclusion, the magnetic parameters χ, χARM, SIRM and ωCaO of paddy soil profiles can indicate well the effect of cement dust on paddy soil, the high values of these parameters usually indicate more serious pollution of cement dust to paddy soil.