A novel approach toward better use of saline soils vis-á-vis the evaluation of microbial responses

Abstract

The refurbishment of soil microbial properties is important for better use of saline soils. This study aimed to evaluate the effi ciency of amendments viz. vermicompost (VC), wood ash (WA) and zeolite (ZL) on microbial properties of two different coastal saline soils viz. soil A (ECe 9.25 mS m -1 ) and soil B (ECe 37.64 mS m -1 ). Amendments were incorporated at the rates of 1% and 2% both as single and combined applications resulting in 14 different treatments. After pre-incubation, the soils were amended and incubated for 72 days at 60% of water holding capacity (WHC). Microbial activity (MA) as measured by absorption in alkali and microbial biomass carbon (MBC) by chloroform fumigation-incubation increased after amendment treatments which were lower at higher salinity. Treatment T6, combination of VC and WA (132 and 112% increase in MA and 248 and 391% increase in MBC respectively for the soil A and soil B compared to their respective control) in both soils opted as the most effective treatment while the effect of ZL addition was not signifi cant. The increase of soil pH and ECe was proportional to the amendment type and application rate. The metabolic quotient (qCO 2 ) data also supported the salt stress abatement by amendment application. Higher rates were not necessarily effi cient in improving soil microbial properties as they imposed further salinity.