TY - JOUR ID - 72530 TI - Mid-term Variations of Biogeochemical Indicators of Soil Quality under Agronomic Conditions JO - Iranian Journal of Soil and Water Research JA - IJSWR LA - en SN - 2008-479X AU - Mohseni, Parisa AU - Keshavarzi, Ali AU - Heidari, Ahmad AU - Maleki-Ghelichi, Elnaz AD - Graduate MSc. Student, Department of Soil Science, Faculty of Agricultural Engineering and Technology, Karaj, Iran AD - Assistant Professor, Soil Science Department, Faculty of Agricultural Engineering and Technology, University of Tehran, Karaj, Iran AD - Professor, Soil Science Department, Faculty of Agricultural Engineering and Technology, University of Tehran, Karaj, Iran AD - Graduate MSc. Student, Department of Agricultural Machinery Engineering, Faculty of Agricultural Engineering and Technology, Karaj, Iran Y1 - 2020 PY - 2020 VL - 51 IS - 1 SP - 119 EP - 133 KW - PCA KW - SQI KW - Standard scoring functions DO - 10.22059/ijswr.2019.282659.668223 N2 - In the present study, mid-term variations in soil quality were studied on the farm scale. The studied area was a research-educational farm of the Agricultural and Natural Resources Campus of University of Tehran covers 260 hectares, with thermic soil temperature and aridic soil moisture regimes, respectively. In this study, the process of improving or destruction of the integrated soil quality index at two depths (0-20 and 20-40 cm) in years of 1379 and 1396 was compared. The minimum data set was determined using the method of two-phases PCA. Definition of standard scoring functions and non-linear fuzzy membership functions were performed through programming in the MATLAB software environment. Covariance-correlation method was used for weighing the selected variables in determining Soil Quality Integrated (SQI) index. The results of this study showed that in most of the adaptive areas of the soil, the incremental and decreasing pattern of the soil quality index in the first and second depths of the previous and present studies were consistent and in some places, this pattern was almost constant. In profiles No. 1, 5, 11 of the previous research which include 27.3% of the samples, and in profiles No. 1, 5, 7, 9 and 18 of the present study which include 20.83% of the samples, the soil quality index at the first depth was less than the one in the second depth. Classification of the soil quality classes for all samples in both years revealed a reduction in soil quality index. So that the soil quality reduced from grade III (45%) and IV (54%) to grade IV (73-75%). UR - https://ijswr.ut.ac.ir/article_72530.html L1 - https://ijswr.ut.ac.ir/article_72530_7917491372e68796cced9173b55c53fe.pdf ER -