Subsurface Soil Compaction and Improvement Strategies: Studies on how compaction occurs, its effects on soil properties and crop growth and how compaction can be alleviated

Soil compaction is caused by tillage equipment, reduced use of organic matter, frequent use of chemical fertilizer and ploughing at the same depth for many years. In field experiments subsurface soil compaction was artificially created with seven tons roller. Number of rolling was considered the extent of compaction. In an adjacent field different improvement measures were incorporated in pre-compacted soil. Treatments were arranged in randomized complete block design replicated four times. After eight weeks soil samples were taken for determination of bulk density and porosity. Compaction treatments progressively increased bulk density between 15 to 26%, while decreased porosity in the range of 14 to 27% over control. An inverse relationship between bulk density and porosity was observed. Different improvement measures decreased bulk density in the range of 13 to 17% over control, however, increased porosity between 15 to 18% over control. Subsurface soil compaction may be redeemed by applying combination of different improvement measures such as addition of farm yard manure, gypsum and deep ploughing etc.