Spatial Variability of Soil Organic Carbon, pH and Electrical Conductivity and Its Influencing Factors in a Watershed of Coastal Region of Odisha, India

ABSTRACT

Soil organic carbon (SOC), as a main component of the carbon cycle, contributes to biological and physico-chemical processes in the soil that influence plant growth and soil health. The pH of soil determines how acidic and basic the soil is, while the electrical conductivity (EC) of soil is used to determine the extent of soil salinity. Therefore, the quantification and spatial distribution of these soil properties are important for agricultural crop planning. In this study, the spatial variability of SOC, pH, and EC in soils of a watershed in Nayagarh (Odisha, India) was analyzed using geostatistical (ordinary kriging) techniques. The study revealed that the experimental semi-variogram of SOC and EC fits well with the spherical model; however, the Gaussian model was found to be the best fit for soil pH. The coefficients of variation for SOC, pH, and EC were 15%, 7.63%, and 40.3%, respectively, which suggests SOC may have moderate variability. SOC had moderate spatial variability, as shown by the nugget to sill ratio. The geostatistical method was able to accurately assess the spatial variability of SOC content and its influencing factors at the study watershed. The findings could help decision-makers and farmers in developing more effective land resource management.

KEYWORDS:

• EC
• ordinary kriging
• Ph
• semivariogram
• SOC
• spatial variability
• watershed

Disclosure statement

No potential conflict of interest was reported by the authors.

Author contributions

Gouranga Kar: Conceptualization, Investigation, Methodology, Writing – original draft; Prasanta Kumar Patra: Data curation, Mathematical analysis, Validation; Arvind Kumar Singh: Writing – review and editing.

Data availability statement

The data that support the findings of this study are available on request from the first author, [G. Kar].

Ethics approval and consent to participate

We all declare that manuscript reporting studies do not involve any human participants, human data, or human tissue. So it is not applicable.

Additional information

Funding

No funding for publication as Open Access.