Available Nitrogen and Phosphorus Status of Saline‐Sodic Soils of Punjab (India)¹

Abstract

Abtract The organic matter content of saline‐sodic soils of Punjab is very low and varies from 0.229 to 0.563%. It is an important cause of low available nitrogen and the correlation coefficient (r = 0.640) is significant. The values of available nitrogen are low in surface and very low in subsurface soils. Values of available phosphorus are medium in surface and low in subsurface saline‐sodic soils. Available nitrogen is very low in the districts of Karnal, Amritsar, and Rohtak, and low in Hissar, Gurdaspur, and Ferozepur. Available phosphorus ranges from very low to low in Rohtak, Hissar, and Gurgaon, but is medium to high in Gurdaspur, Ferozepur, Karnal, and Amritsar. pH has a significant effect on the availability and fixation of nutrients. Significant negative correlation coefficients between pH and available nitrogen (r = 0.444) and pH and available phosphorus (r = 0.362) have been found.

Assessment of Soil Fertility Status under Different Cropping Sequences in District Kapurthala

“…Although, the negative correlation was observed with available phosphorus be due to fixation of phosphorus under high pH conditions. Similar results were reported by Chawla (1969) that pH and available phosphorus (r=0.362) have negative significant correlation. The organic carbon was found to be non-significantly correlated with pH and EC.…”