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A total of 176 homestead forests at three altitudes in the Chittagong Hill Tracts, Bangladesh were randomly surveyed to estimate carbon (C) stocks and how stand structure affects the biomass C. All woody vegetations were measured, and litter and soil (0–30 cm depth) were sampled. The tree biomass C stock in the top two altitude forests was up to 37–48% higher than in low altitude, owing to significantly higher tree density and species diversity. An increase in species diversity index by one unit increased the biomass stock by 23 Mg C ha−1. The C stock of litterfall in low altitude forests was 22–28% higher than in the top two altitude due to the deposition of litters downslope and deliberate use of mulch for soil improvement and conservation, resulting in up to 5% higher total soil C. The topsoil C was 10–25% higher than the deeper soil, depending on the altitude. The forest stored 89 Mg C ha−1, indicating a potential for C sequestration in trees outside forest. This study would help policymakers to strengthen the recognition of small-scale forests for mitigation in REDD + (reducing emissions from deforestation and forest degradation, the role of conservation, sustainable management of forests, and enhancement of forest carbon stocks) and support owners through C credits from sustainably managed forests.

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Purpose For sustaining productivity and increasing biodiversity in Cox´s Bazar, a coastal area, and Bandarban, a hilly area, in Bangladesh, it is important to study the soil properties of the homegardens in these districts. We assessed the effects of varying forest management on soil carbon (C), nitrogen (N), and nutrients (P, K, Na, and Ca) between the hill and coastal homegardens. Methods Soil samples were collected from 24 homegardens; 12 from the hill and 12 from the coastal sites. ResultsIn both homegardens, the topsoil C and N stocks were up to 23% and 41%, respectively, higher than those in the deepest soil. We found a vertical decrease in C:N ratio in the soil of both homegardens, and the highest C:N ratios and C stock (49.90 Mg ha −1 ) were in the hill homegardens. The topsoil C in the hill homegardens was higher most probably due to higher deposition of litterfall and/or lower litter harvesting or mulching. The highest total N stock (5.97 Mg ha −1 ) was in the coastal homegardens, which may be due to higher tree density and species composition. The concentration and stocks of nutrients decreased vertically in the soil and this decrease was higher in the hill than in the coastal homegardens (except for P). Conclusions It could be concluded that overall nutrient dynamics may be significantly affected by litter deposition, stand structure, and the variation in the rainfall. Soil N and nutrient deficiency should be considered in the planning of sustainable forest management to sustain productivity and increase biodiversity.