Soil Carbon Sequestration in Agroforestry Systems as a Mitigation Strategy of Climate Change: A Case Study from Dinajpur, Bangladesh

Abstract

The study was carried out in three different locations in Dinajpur district, Bangladesh，to observe soil carbon sequestration in agroforestry systems as a mitigation strategy for climate change. A total of 108 composite soil samples were collected at 0-30 cm in different study area sites. The total number of samples comprised three agroforestry systems (cropland agroforestry, homestead agroforestry, and orchard agroforestry)， where 36 samples were collected from each agroforestry system. Three adjacent soil samples were collected from each agroforestry system and mixed to get composite soil samples. The outcomes revealed that the soil organic carbon (SOC) and soil organic matter (SOM) changes over the age of the orchard. Moreover, the results indicated that there are significant differences among the systems. The highest SOC (1.60%) was found in Eucalyptus woodlot-based agroforestry system，and the lowest SOC (0.29%) was found in the Mahogany woodlot-based agroforestry system although both organic carbon and organic matter are deficient compared to the optimum level. Furthermore, in the case of soil pH, the highest value (5.45) was recorded under the Mango tree，while the lowest value (5.12) was recorded under the Mahogany tree. Based on the findings, the study determined that all the collected samples were acidic. The investigation concluded that most species of homestead agroforestry systems provide maximum SOC and SOM as compared to cropland and orchard. The present study provides significant recommendations for soil carbon enrichment and environmental safety practices in the agroforestry systems to mitigate climate change through soil carbon management.