Fig 1.
Study area in southern part of Bara district, Nepal which includes 23 Village Development Committees (VDCs).
A large part of the study area lies in Terai region where the topographic variation ranges from 80 to 95 m, and climate is subtropical monsoon. A total of 109 soil samples were taken from the depth of 0–15 cm (topsoil layer) for determination of pH, OM, N, P2O5, K2O, Zn and B status on it.
Table 1.
Methods used for testing of soil chemical parameters at Regional Soil Testing Laboratory, Kaski district of Nepal.
Table 2.
Summary statistical overview for selected soil chemical properties of study area (N = 109), including original and log transformed data (for skew and kurtosis).
Table 3.
Range for different soil parameters given by the Soil Management Directorate, Department of Agriculture for Terai region of Nepal.
Fig 2.
Soil pH spatial variability map in southern part of Bara district, Nepal.
Most of the study area was with moderately alkaline (30.69%) followed by moderately acidic (22.91%) and neutral (22.80%) pH. Strongly alkaline was present in about 2.5% of total area but could not see in the variable map.
Fig 3.
Soil OM spatial variability map in southern part of Bara district, Nepal.
Most of study area was with low (48.80%) and very low (26.88%) OM content.
Fig 4.
Soil N spatial variability map in southern part of Bara district, Nepal.
Most of study area was with low (50.86%) for total N content.
Fig 5.
Soil P2O5 spatial variability map in southern part of Bara district, Nepal.
Most of study area was with medium (42.95%) and low (29.88%) for available P2O5.
Fig 6.
Soil K2O spatial variability map in southern part of Bara district, Nepal.
Most of study area was with low (41.19%), followed by very low (30.77%) and medium (21.79%) for available K2O.
Fig 7.
Soil Zn spatial variability map in southern part of Bara district, Nepal.
Almost of the study area was with very low (98.33%) for Zn content.
Fig 8.
Soil B spatial variability map in southern part of Bara district, Nepal.
Most of study area was with low (55.52%) and medium (43.21%) for B content.
Table 4.
Areas under different soil categories based on soil fertility parameters.
Table 5.
Semivariance analysis of spatial structure in soil chemical properties.
Table 6.
Test of significance of pattern analysis for selected soil chemical properties.