Multivariate Assessment of Variability and Relationships of Soil Parameters Under Semi-Arid Alfisols Using Principal Component Analysis

ABSTRACT

Multivariate relationships and variability of initial and post-harvest soil parameters in the North and South Transects of Bengaluru during 2017 and 2018 are assessed. North (South) Transect soils indicated initial pH of 5.9 (7.1), EC of 0.17 (0.16) dS m⁻¹, N of 376.9 (415.3) kg/ha, P₂O₅ of 83.18 (64.31) kg/ha, K₂O of 169.7 (247.3) kg/ha, Fe of 11.78 (10.86) ppm, Zn of 1.59 (1.13) ppm, Cu of 0.71 (0.6) ppm, Mn of 8.24 (7.74) ppm and B of 0.24 (0.21) ppm; compared to post-harvest pH of 6.1 (6.8), EC of 0.26 (0.19) dS m⁻¹, N of 352.5 (383.4) kg/ha, P₂O₅ of 68.05 (54.14) kg/ha, K₂O of 153.5 (222.1) kg/ha, Fe of 9.91 (8.75) ppm, Zn of 1.35 (0.93) ppm, Cu of 0.58 (0.53) ppm, Mn of 6.88 (6.72) ppm and B of 0.20 (0.19) ppm. Four PCs of post-harvest parameters explained a maximum variance of 59.85% in the North compared to 69.94% in the South Transects. Soil pH (−0.623), Fe (0.648), Zn (−0.603) on PC-1; Cu (0.628) on PC-2; EC (0.613) on PC-3; and B (−0.657) on PC-4 were significant in North, while pH (−0.715), Fe (0.891), Zn (−0.624), Mn (0.835) on PC-1; EC (0.771), N (0.618) on PC-2; K₂O (0.718), B (0.774) on PC-3; P₂O₅ (0.673), Cu (0.647) on PC-4 were significant in South Transect. It may be recommended that the package of practices of crops should be modified by considering variability, relationships, loadings, and buildup of soil fertility parameters under semi-arid Alfisols.

KEYWORDS:

• Alfisols
• correlation
• principal components
• regression
• soil fertility
• variability

Acknowledgements

The authors are grateful to the Vice-Chancellor, University of Agricultural Sciences, GKVK, Bengaluru, Karnataka for providing all the facilities for conducting the research study. The authors are also grateful for the funding received under the Indo-German project from the Department of Biotechnology, Government of India for carrying out the research study.

Disclosure statement

No potential conflict of interest was reported by the author(s).