Carbon sequestration as affected by tillage practices and fertilizer application

The study was conducted at the Agricultural Experiment Center, Central Mindanao University [Philippines]. It aimed to determine the soil chemical properties such as pH, organic matter content, extractable phosphorus and exchangeable potassium as affected by tillage practices and fertilizer application; to evaluate the soil organic carbon and plant carbon as potential C stock; and to determine the yield components of corn as affected by tillage practices and fertilizer application. The experiment was laid out following factorial in Randomized Complete Block Design in three replications with tillage practices (No tillage and conventional tillage) as factor A and inorganic and organic fertilizer (No Fertilizer, 60-30-100 kg N-P sub 2 O sub 5-K sub 2 O/ha, 2 tons Vermicompost/ha and 4 tons Vermicompost/ha) as factor B. The different tillage system and fertilizer application affects the soil chemical properties. It was found out that the soil was strongly acidic (pH of 4.67 to 5.04), has marginal organic matter content (2.49 to 3.59%), high extractable phosphorus (14.45 to 21.78 mg/kg), and exchangeable potassium (0.191 to 0.37 cmol/kg). Results shows that the interaction of tillage practices and kind of fertilizers applied had significant effect on soil organic carbon, corn grain yield and weight of 1000 seeds. Corn plants under conventional tillage applied with 4 tons vermicast/ha and 30-60-100 of N-P sub 2 O sub 5-K obtained the highest grain yield and heaviest 1000 seeds weight. Across the tillage practices, the two practices did not significantly differ in all chemical properties. Highest soil organic carbon sequestered was obtained in no tillage and yield parameters was found significant on conventional tillage. Soil organic carbon, grain yield and weight of 1000 seeds were significantly affected by the fertilizers. However, further study is suggested to validate this result.