The Effects of Sustainable Agricultural Practices on Biological Activities
Objective: This study systematically reviews the quantitative and qualitative impacts of sustainable agricultural practices including organic amendments, conservation tillage, and plant growth-promoting microorganisms (PGPMs) on soil enzymatic activities, microbial diversity, and plant biochemical responses. Methodology: A systematic literature search was conducted across Web of Science, Scopus, and PubMed databases targeting peer-reviewed studies published between 2015 and 2026. A final cohort of 87 studies meeting strict inclusion criteria (focusing on quantifiable microbial, enzymatic, and biochemical parameters) was synthesized. Results: The meta-synthesis revealed that transition from conventional to organic management significantly enhances soil organic matter (SOM) by 24–38% (p<0.01). Dehydrogenase, acid phosphatase, and urease activities exhibited average increases of 42%, 35%, and 29% respectively under conservation tillage compared to intensive conventional systems (p<0.05). Microbial biomass carbon (MBC) increased by up to 55% under PGPM inoculation (p<0.001), driving a parallel increase in plant secondary metabolite accumulation (phenolics and flavonoids) by 18–30%. Conclusion: Sustainable soil management represents a highly efficient biological strategy that actively restores rhizosphere functional networks, improves nutrient-use efficiency, and mitigates chemical degradation.