LAUSR

This study was aimed to assess soil nutrient status, heavy metal content, and their impact on phosphate solubilizing bacteria (PSB) as well as to determine relationship between PSB and coliform in soils of urban area of Patna town during monsoon and winter. The eight sampling areas are included for study namely Bazar Samiti (S1), Moin-ul-Haq Stadium (S2), Agamkuan (S3), Kumhrar (S4), Beur Jail (S5), Phulwari Sharif (S6), BIT Campus (S7), and Danapur (S8). Nutrients, such as carbon, phosphorus, and potassium, varied with seasons and sites. The average concentration of heavy metals for monsoon followed the order Mn > Zn > Co > Pb > Cu > Ni > Hg, while for winter the order was Mn > Zn > Pb > Co > Cu > Ni > Hg, whereas Cd was below detection limit (0.1 ppm) in all sites. To evaluate the degree of pollution in soils of Patna region contamination factor (CF), enrichment factor (EF), geo-accumulation index (Igeo), and pollution load index (PLI) were calculated. An elevated concentration of Mn and Zn was reported on most of the sites; however, PLI showed that soils have become polluted with heavy metals. In addition, enumeration of bacterial cells revealed that PSB grew efficiently in winter when pH (6 to 6.8) was low, which might be due to production of organic acids, and coliform count was moderate to low. The negative correlation between PSB and coliform in winter suggests that both the species are competitor of each other.