_____________________________________________________________________________________________________ ++ Ph. D Scholar; # Professor; † Associate Professor; ‡ Assistant Professor; *Corresponding author: E-mail: aparna.b@kau.in; Int. J. Environ. Clim. Change, vol. 13, no. 11, pp. 2939-2949, 2023 International Journal of Environment and Climate Change Volume 13, Issue 11, Page 2939-2949, 2023; Article no.IJECC.108695 ISSN: 2581-8627 (Past name: British Journal of Environment & Climate Change, Past ISSN: 2231–4784) Organic Carbon and Biological Properties of Soils in Various Agro-Ecological Units of Kerala, India Adilakshmi K. a++ , Aparna B. a#* , Rani B. a# , Gladis R. a† , Naveen Leno a‡ , Usha C. Thomas b# and Visveswaran S. a‡ a Department of Soil Science and Agricultural Chemistry, Kerala Agricultural University, India. b Department of Agronomy, Kerala Agricultural University, India. Authors’ contributions This work was carried out in collaboration among all authors. All authors read and approved the final manuscript. Article Information DOI: 10.9734/IJECC/2023/v13i113464 Open Peer Review History: This journal follows the Advanced Open Peer Review policy. Identity of the Reviewers, Editor(s) and additional Reviewers, peer review comments, different versions of the manuscript, comments of the editors, etc are available here: https://www.sdiarticle5.com/review-history/108695 Received: 27/08/2023 Accepted: 03/11/2023 Published: 15/11/2023 ABSTRACT A study was carried out in four agro-ecological units (AEUs), viz., southern laterites (AEU 8), south central laterites (AEU 9), north central laterites (AEU 10), and the northern laterites (AEU 11) of Kerala, with the objective of detailing the soil fertility status of the study area and unveiling the relationship between organic carbon (OC) and various biological properties of soils, like population of phosphorus solubilizers and acid phosphatase activity, by following one-way analysis of variance (ANOVA). The findings of the study revealed that the average values of OC among the four AEUs varied from 0.63 to 0.82%, and remarkably, 98% of the collected soils displayed OC content ranging from 0.5 to 1.5%. The mean values for the population of phosphorus solubilizers ranged from 3.12 to 3.34 log cfu g -1 soil. The acid phosphatase activity also varied across the study area, Original Research Article