The effects of compaction on wheat yield in Pakistan | |
| Author | Qaisrani, Abdul Rashid |
| Call Number | AIT Thesis no. AE-87-17 |
| Subject(s) | Wheat--Pakistan Soil stabilization |
| Note | A thesis submitted in partial fulfillment of the requirement for the degree of Master of Engineering. School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Abstract | Results of field experiments with soil compaction induced by tractor passes applied uniformly to cover the entire surface of experimental plots are reported. Compaction was done immediately before sowing . The number of passes varied between 0 and 12. The experiment was conducted during the year 1986-87 in the same location with two different tyre pressures on wheat crop. The soil parameters such as cone penetrometer resistance and dry bulk density were increased with the increase of tractor passes and tyre pressure. Void ratio and porosity were decreased with the increase of tractor passes and tyre pressures. These parameters have achieved almost their maximum values with 4 passes and at 10-20 cm depths . All the soil parameters at high compaction levels decreased with time, where as low compaction levels showed an increase with time. Moreover all the soil parameters were observed maximum at 10-20 cm, small at 20-30 and zero at 30-40 cm depths. Grain yield and plant population were also adversely affected by wheel passes and tyre pressure. The average maximum decrease in plant population was 46% and average maximum decrease in yield was 63% at 12 passes with HTP as compared with non compacted plots. Root developments and plant heights were also adversely affected by tractor passes . All these affects were more severe at high tyre pressure as compared to those at low tyre pressures. |
| Year | 1987 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Agricultural and Food Engineering (AE) |
| Chairperson(s) | Gee-Clough, D. |
| Examination Committee(s) | Gupta, Chandra P. ;Singh, Gajendra |
| Scholarship Donor(s) | Government of Switzerland |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1987 |