Soil Carbon Sequestration in Rice-Based Cropping Systems in Batac, Philippines

This study focused on the assessment of capacity of farm soils to sequester carbon under different rice-based cropping patterns. The results of this study may be valuable for the formulation of soil and crop management for climate change mitigation in the agriculture sector in Ilocos Norte, Philippines. This study was conducted in major cultivated areas in the City of Batac, characterized by intensified and diversified cropping patterns centered around rice cultivation. A quantitative research design was employed to determine the different cropping patterns and their influence on soil organic carbon (SOC). The dominant cropping patterns observed in Batac City was rice, followed by any of the following crops; corn, shallot, eggplant, rice, tomato, pepper, garlic and tobacco. These cropping patterns are assumed to have an influence in soil pH, organic matter (OM), % carbon, phosphorus (P), potassium (K), bulk density, soil texture, moisture content, and soil carbon stock (SOC). Results showed that soil organic matter content in various cropping patterns was proportional to the soil carbon stock in the soil. The analysis of variance between cropping patterns exhibited high variability in OM and SOC with an F-value >1. Rice-tobacco exhibited the highest carbon stock (1.80%), while rice-garlic (0.63%) and rice-corn (0.60%) had the lowest. Understanding the influence of crop biomass and management through this study can be beneficial in the design of informed decision-making strategies and advocacy on cropping pattern management, which can be disseminated to farmers to enhance the carbon sequestration potential of agricultural lands.