Plant-microbe interactions are pivotal in shaping terrestrial ecosystem processes, especially as climate change accelerates. Rising atmospheric CO₂ and global warming are altering ecosystem dynamics, making it essential to understand how plants and soil microbes collaborate to influence carbon sequestration, nutrient cycling, and ecosystem resilience. This chapter highlights the significance of mutualistic partnerships, such as those with mycorrhizal fungi and plant growth-promoting rhizobacteria, alongside specialized processes like the oxalate–carbonate pathway (OCP), in which plant-derived oxalate is transformed by microbes into stable soil carbonates. Field studies in Indian forests, particularly under oxalogenic trees like Terminalia alata, reveal that these interactions can enhance soil pH, calcium carbonate content, and fertility, while supporting diverse communities of beneficial bacteria and fungi. Climate change-induced stresses, such as increased temperature and altered rainfall, can disrupt plant-microbe relationships, potentially affecting ecosystem functions. Nevertheless, microbial diversity and functional redundancy offer resilience, helping maintain critical processes like nutrient cycling and long-term carbon storage. Practical applications, including agroforestry, reforestation, and microbial inoculants, leverage these plant-microbe partnerships to boost soil carbon sequestration, restore degraded lands, and promote sustainable agriculture in a changing climate. In summary, plant-microbe interactions are a vital but underutilized tool for climate change mitigation. Advancing our knowledge of these relationships through field research, molecular techniques, and biotechnology can unlock new strategies for sustaining ecosystem services, improving soil health, and enhancing carbon sequestration in terrestrial environments.