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Not AvailableSoil compaction by machinery traffic in agriculture is a well recognised problem in many parts of the world. To characterize the state of compactness of a soil layer, bulk density (BD) and total porosity are the most frequently used parameters. It is known that exchangeable sodium percentage (ESP), exchangeable Mg2+ and pH bear a close relationship with BD. This is because higher values of these properties cloggs the macropores (sometimes micropores) and increases the BD. If the size, nature and amount of these pores can be determined, it may be useful to explain the changes in BD in soils and also help to take proper crop management decisions. Soil micromorphology can be used as a viable tool to assess such pores in soils. Therefore, the present study has been taken up to study some micromorphology thin sections of some benchmark Vertisols from Maharashtra and the image analysis of the soil micrographs to find the amount of pores was done using geographic information system (GIS). BD of soils was determined by three methods, viz. field moist core method, wax clod coating method and pycnometer method. The soils were mainly benchmark Vertisols from Maharashtra as well as random samples collected upto 30cm depth within the study area. Micromorphological studies showed the presence of mainly micropores, whereas macropores were not found in all the soils. The micropores decreased with depth and were observed more in the surface horizons of Paral in Akola and Sait and Asra soils in Amravati districts of Maharashtra. Multiple regression analysis showed significant relationship between field moist core BD and micropores (%) and OC (%) with R2 value of 0.78 and standard error of 0.0813. The saturated hydraulic conductivity is also significantly related with the micropore (%) and OC (%) with R2 value of 0.77 and standard of error of 0.4324 which is less than the standard deviation of observed values i.e. 0.8221. The study also indicated that the field (moist core) BD and the wax clod method drawn bulk density are more effective in interpreting soil properties as they were also well correlated with the amount of micropores. The study exemplified that soil micromorphological thin section study in typical benchmark soils is effective in determining the amount of pores and also explained the reasons for the changes in BD with depth as related to the chemistry of soils. The increase in bulk density with depth was accentuated by the decrease in the quantity of pores in the subsurface soils. This was also reflected by the deteriorating structure of soils and increasing firmness of moist soil consistence. Therefore, increase in bulk density and decrease in the amount of pores with depth can be considered as an important soil quality parameter in the study area. Soil compaction which increases the BD by decreasing the amount of pores causing soil degradation can be prevented by adopting proper management practices that in the long term should be able to preserve good soil structure by minimizing the use of heavy machinery tillage operation and application of FYM regularly and specifically gypsum in problematic soils.Not Availabl