26
year of the test, the average value of soil available P in
0-40 cm depth had increased to 11.1-6.8 mg kg-1 for S1-
S5 treatment.
Soil available .
$Iter $t the end oI the finDO yeDr oI the tests the soiO DYDiODbOe
K was seen to have arrived at a range of range of 155-179
Pg Ng in cP deSth oI soiO Ior the fiYe treDtPents
At higher SMP thresholds, soil reclamation was observed
to be Pore eIficient both Ior nXtrients Dnd Ior strXctXre
Zhich rDtified the diIIerences DPong the fiYe treDtPents in
SOC each year.
Cotton yield and soil carbon to nitrogen C:N ratio
The highest seed cotton yields for both years two and three
were in the S1 Treatment sector, where the yields were
67 and 84% of the average level for non-saline soil in this
region, respectively.
Conclusions
During the course of the trial, the levels of soil salinity, sodicity
Figure Three: Total nitrogen (TN) content at 0–40 cm depth
before seeding in year one and after irrigation terminated
in years one, two and three for each treatment
Figure Two: Monthly rainfall and mean temperature during
experimental stages during trial years one, two and three