• Journal of Forest and Environmental Science
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• v.37 no.2
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• pp.141-147
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• 2021

An experiment was conducted to observe the effect of polybag size on the growth and quality of Khaya anthotheca seedlings during September 2016 to June 2017 at the nursery of Silvicultural Research Division of Bangladesh Forest Research Institute. Three different polybag size such as T₁ (15 cm×23 cm), T₂ (13 cm×18 cm) and T₃ (11 cm×15 cm) with four replications were used for the experiment. The experiment was designed in Completely Randomized Design (CRD) with four replications. Different sized polybags showed significant influence on survival percentage (T₁-100%, T₂-93.5%, T₃-88%) and growth parameters (height, root collar diameter, leave number and root length) of the seedlings. The species grown in T₁ size polybag was observed to be superior to other bag size. Dickson's Quality index of seedlings raised in T₁ size polybag was observed highest value which is the indicator of best quality seedlings. Therefore, the use of T₁ poly bag size can be suggested for seedling production of K. anthotheca in the nursery.

• Journal of Forest and Environmental Science
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• v.30 no.2
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• pp.208-217
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• 2014

Leaf litter is the main and quick source of organic matter and nutrient to the soil compared to other parts of litter. This study focused on the nutrients (N, P and K) leaching from leaf litter of Melia azadirachta, Azadirachta indica, Eucalyptus camaldulensis, Swietenia macrophylla, Mangifera indica, Zizyphus jujuba, Litchi chinensis, Albizia saman, Artocarpus heterophyllus, Acacia auriculiformis, Dalbergia sissoo and Khaya anthotheca as the common cropland agroforest tree species of Bangladesh. About (9 to 35) % of initial mass was lost, while Electric Conductivity (EC) and TDS (Total Dissolved Solid) of leaching water increased to (573 to 3,247) ${\mu}S/cm$ and (401 to 2,307) mg/l respectively after 192 hours of leaching process. Mass loss (%) of leaf litter, EC and TDS of leaching water showed significant (ANOVA, p<0.05) curvilinear relationship with leaching time. Initial concentration of NH4, PO4 and K in leaching water was found to increase significantly (p<0.05) up to 48/72 hours and then remained almost constant at later stages (48/72 to 192 hours). Mass loss of leaves; EC, TDS, $NH_4$, $PO_4$ and K in leaching water was varied also significantly (ANOVA, p<0.05) among the studied tree species. All the tree species showed similar pattern of nutrients (K>N>P) release during the leaching process. The highest $NH_4$ (4,097 ppm) and potassium (8,904 ppm) concentration was found for M. azadirachta while the highest $PO_4$ (1,331 ppm) concentration was found for E. camaldulensis in the leaching water. Among the studied tree species, M. azadirachta, A. indica, D. sissoo, E. camaldulensis and Z. jujuba was selected as the best tree species with respect to nutrient leaching.