Assessing the Role of Sacred Forests in Maintaining Soil Carbon Stocks in Imo State, South East Nigeria

Sacred forests represent an understudied category of informal conservation areas that may contribute significantly to landscape-level carbon storage in parts of South East Nigeria where formal protection is limited. This study assessed the role of sacred forests in maintaining soil carbon stocks by comparing soil carbon pools in sacred forests, secondary forests, and croplands across sixteen communities in Imo State. Soil samples were collected from three depth increments (0 to 10, 10 to 30, and 30 to 60 centimetres) at five plots per land cover type per community. Soil organic carbon concentration and bulk density were determined, and total soil organic carbon stocks were calculated for each land cover type. Microbial biomass carbon was measured as an indicator of active carbon pool dynamics. Structural equation modelling examined direct and indirect predictors of soil carbon stocks including canopy cover, litter depth, and soil moisture. Results showed that sacred forests stored on average 187 tonnes of carbon per hectare to 60 centimetres depth, compared to 134 tonnes in secondary forests and 68 tonnes in croplands. Sacred forests also supported significantly higher microbial biomass carbon, indicating more active carbon cycling. Canopy cover and litter depth were the strongest predictors of soil organic carbon stocks. The study demonstrates that sacred forests function as important landscape carbon stores and recommends their formal recognition in Nigeria's national forest carbon accounting and REDD-plus frameworks. Keywords: sacred forests, soil carbon, Imo State, carbon stocks, informal conservation.