Vol. 8, Issue 8 (2019)

Author(s):
Indira Sarangthem, Kondareddy AN and L Devarishi Sharma

Abstract:
The Zinc content in six soil chemical fractions was determined in twenty four soil samples collected from different paddy fields of Gamdeiphai, Sadukoireng, Utonglok, Saijang villages of Saikul block of Kangpokpi district of Manipur using Stratified Random Sampling with proportionate allocation, to investigate the form of spontaneously accumulated Zn in the hill soils of Manipur and also to study the correlation coefficient between zinc fractions and soil properties. Sequential extraction was applied to every soil and each Zn fraction was designated. The water soluble and exchangeable zinc fractions (WSEX-Zn) varied from 0.45-0.93 mg kg-1 (mean 0.76 mg kg-1), organically bound zinc fractions (OC-Zn) 2.40-6.12 mg kg-1 (mean 4.65 mg kg-1), amorphous sesquioxide bound zinc (AMOX-Zn) 2.82-4.70 mg kg-1 (mean 3.69 mg kg-1), crystalline sesquioxide bound zinc (CRYOX-Zn) 1.08-2.20mg kg kg-1 (mean 1.52 mg kg-1 ), manganese oxide bound zinc (MN-Zn) 0.98-4.69mg kg-1 (mean 2.30 mg kg-1) and residual form of zinc (RES-Zn) varied from 58.91-100.32 mg kg-1 (mean 78.99 mg kg-1). Thus the different fractions of zinc viz. WSEX-Zn, OC-Zn, AMOX-Zn, CRYOX-Zn, MN-Zn and (RES-Zn) form constituted 0.83%, 5.06%, 4.01%, 1.65%, 2.50%, 85.95% of total zinc content in soils respectively. All the soil samples were acidic in reaction ranging from pH 4.5 to 6.06 with mean value of 5.20, electrical conductivity is ranging from 0.06 to 0.20 dSm-1 with mean value of 0.10 dSm-1, organic carbon content 0.30 to 1.59% with mean value of 0.91%, cation exchange capacity of the soils 9.2 to 23.6 [cmol (p+) kg-1] with mean value of 15.60 [cmol (p+) kg-1] and the clay content of soil varied from 33.50 to 54.40% (mean 45.39%). The DTPA zinc ranged from 0.30-1.36mg kg-1 (mean 0.88 mg kg-1) and total zinc 71.94-112.62 mg kg-1 (mean 91.90 mg kg-1).