Allelopathic effects of different doses of Eucalyptus camaldulensis leaf litters were investigated through an experiment in the green house of Institute of Forestry and Environmental Sciences, Chittagong, Bangladesh. ...Allelopathic effects of different doses of Eucalyptus camaldulensis leaf litters were investigated through an experiment in the green house of Institute of Forestry and Environmental Sciences, Chittagong, Bangladesh. Three popular agricultural crops： Falen （Vigna unguiculata）, Chickpea （Cicer arietinum）, Arhor （Cajanus cajan） and two widely used plantation trees： Sada koroi （Albizia procera） and Ipil ipil （Leucaena leucocephala） were selected as bioassay species. Experiment was set on tray at room temperature 27℃. The effects of different doses of leaf litter extracts were compared to the control. Results suggest that leaf litters of E, camaldulesis induced inhibitory effects, It was also found that the effect depend on concentration of extract and litterfall, type of receiver species. Higher concentration of the materials had the higher effect and vice versa. Though all the bioassay species were suppressed some of them showed better performance. Vigna unguiculata, Cicer arietinum are recommended in agroforestry based on this present Experiment output. In mixed plantation, Leucaena leucochephala is a better choice while compared to Albizia procera.展开更多
An experiment was conducted to assess the effect of leaf litter of Leucaena leucocephala on two forest crops Sada koroi （Albizia procera）, Ipil ipil （L. leucocephala） and three agricultural crops Falen （Vigna ung...An experiment was conducted to assess the effect of leaf litter of Leucaena leucocephala on two forest crops Sada koroi （Albizia procera）, Ipil ipil （L. leucocephala） and three agricultural crops Falen （Vigna unguiculata）, Chickpea （Citer arietinum） and Arhor （Cajanus cajan） in the nursery of the Institute of Forestry and Environmental Sciences, Chittagong University, Bangladesh, in a Randomized Block Design. Results suggested that leaf litters ofL. leucocephala induced inhibitory effects on germination and growth of bioassay. It was also found that the effect depended on concentration of extract and litterfall, type of receptor species. Higher concentration of the materials had the higher effect and vice versa. Growth response of receptor crops varied with the variation of leaf litter application. The study revealed that application of low-dose leaf litter specially litter of 10 g·m^-2 had stimulating effect on shoot growth of C. arietinum, Vunguiculata and A. procera. While in all other cases significant inhibitory effect was observed and it was significantly increased with the increase of leaf litter application. However, the trend of inhibition was uneven with treatments. Root growth was found to be more affected than shoot growth.展开更多
Triple Super Phosphate, TSP fertilizer, was applied @ 80 kg·ha^-1 as the source of phosphorous on six months old polybag seed- lings of Albizia chinensis, Albizia saman and Pongamia pinnta in nursery beds in Bang...Triple Super Phosphate, TSP fertilizer, was applied @ 80 kg·ha^-1 as the source of phosphorous on six months old polybag seed- lings of Albizia chinensis, Albizia saman and Pongamia pinnta in nursery beds in Bangladesh. The effects of P-fertilizer on seedling growth and nodulation were comparcd to that of seedlings grown in unfertilized soil or in control at different harvesting intervals. The study revealed that, seedling growth was enhanced significantly with the application of P-fertilizer. The growth was found more pronounced in cases of A. saman and P. pinnata, whereas it was not noticeable and showed depressed growth in case of A. chinensis. The study also suggests that nodulation in terms of nodule number and size was also increased significantly with P-fertilization except in case ofP. pinnata, where higher harvesting intervals lowered the nodulation performance of that species展开更多
An experiment was conducted to observe the inhibitory effects of the leaf extracts derived from Albizia lebbeck （L.） Benth. On germination and growth behavior of some popular agricultural crops （receptor） of Bangl...An experiment was conducted to observe the inhibitory effects of the leaf extracts derived from Albizia lebbeck （L.） Benth. On germination and growth behavior of some popular agricultural crops （receptor） of Bangladesh. Experiments were set on sterilized petridishes with a photoperiod of 24 h at room temperature of 27-30℃. The effects of the different concentrations of aqueous extracts were compared to distil water （control.）. The aqueous extracts of leaf caused significant inhibitory effect on germination, root and shoot elongation and development of lateral roots of receptor plants. Bioassays indicated that the inhibitory effect was proportional to the concentrations of the extracts and higher concentration （50%-100%） had the stronger inhibitory effect whereas the lower concentration （10%-25%） showed stimulatory effect in some cases. The study also revealed that, inhibitory effect was much pronounced in root and lateral root development rather than germination and shoot growth.展开更多
An experiment was conducted to understand the growth inhibitory effects of aqueous extracts derived from Lantana camara L. （a globally recognized invasive alien weed） on six popular agricultural crops of Bangladesh....An experiment was conducted to understand the growth inhibitory effects of aqueous extracts derived from Lantana camara L. （a globally recognized invasive alien weed） on six popular agricultural crops of Bangladesh. The test was conducted in sterilized petridishes with a photoperiod of 24 hours and an average temperature of 29℃. The effect of different concentrations ofL. camara leaf extracts were recorded and compared with control （i.e., distil water）. Result showed different concentrations of aqueous leaf extracts caused significant inhibitory effect on germination, root and shoot elongation and development of lateral roots of receptor crops. Bioassays also indicated that the inhibitory effect was proportional to the concentrations of the extracts and higher concentration had the stronger inhibitory effect whereas the lower concentration showed stimulatory effect in some cases. The inhibitory effect was much pronounced in root and lateral root development rather than shoot and germination.展开更多
The effects of different inorganic fertilizers （Urea and Triple Super Phosphate （TSP）） on seedling growth and nodulation capabilities of four agroforestry tree species （Albizia chinensis, A. saman, Acacia nilotic...The effects of different inorganic fertilizers （Urea and Triple Super Phosphate （TSP）） on seedling growth and nodulation capabilities of four agroforestry tree species （Albizia chinensis, A. saman, Acacia nilotica and Sesbania sesban） were compared. The nodulation of these seedlings were treated with different fertilizer treatments （at the rate of urea 40 kg·hm^-2, urea 80 kg·hm^-2 TSP 40 kg·hm^-2, TSP 80 kg·hm^-2, （urea＋TSP） 40 kghm 2 and （urea＋TSP） 80 kg·hm^-2） after one month of seed germination. The results revealed that the seedling growth was enhanced significantly with moderate fertilizer treatment. In some cases, the higher levels of fertilizers reduced the seedling growth. The study also revealed that the nodulation in nodule number and size was significantly inhibited by the application of N fertilizer （Urea）, while it was increased significantly with the application of P fertilizer （TSP）. This study improved our understanding and provided insights that would be useful to the farmers in their efforts to amend the soil with inorganic fertilizers in order to enhance plant growth and biological nitrogen fixation.展开更多
We focused on key aspects of forest governance for biodiver- sity conservation in implementing new climate change policies. The national forest institutions must be adaptive to identify the existing pitfalls of prior ...We focused on key aspects of forest governance for biodiver- sity conservation in implementing new climate change policies. The national forest institutions must be adaptive to identify the existing pitfalls of prior conservation policies to take advantage of new climate change policies. Strengthening roles and technical capacity of national institutions for systematic biodiversity monitoring and carbon stock assessment is required in developing and least developed countries. Community participation needs careful analysis to ensure equitable ac- cess of particular social groups to local decision-making processes and to sustain optional livelihoods. The livelihood options around forest reserves or protected areas must be taken into account to enhance forest-based adaptation.展开更多
An experiment was conducted to assess the effect of Phosphorous （P） fertilizer （i.e. TSP or triple super phosphate @ 80 kg/hm^2） on seedling growth and nodulation capabilities of three potentially important agrofo...An experiment was conducted to assess the effect of Phosphorous （P） fertilizer （i.e. TSP or triple super phosphate @ 80 kg/hm^2） on seedling growth and nodulation capabilities of three potentially important agroforestry tree species （Acacia auriculiformis, Albizia lebbeck and Albizia procera） of Bangladesh. The study was conducted in nursery beds with six-month-old polybag seedlings ofA. auriculiformis, A. lebbeck and A. procera. The effects of P fertilizer on seedling growth and nodulation were compared with that of the seedlings grown in control （i.e. unfertilized soil）. The observations revealed that the seedling growth was enhanced significantly with the application of P fertilizer. The growth was found more pronounced in A. auriculiformis, whereas it was not apparent and shows depressed growth in case ofA. lebbeck. The study also suggests that the nodulation in terms of nodule number and size was also increased significantly with the application of P fertilizer.展开更多
Teak plantations date back to 1871 in Bangladesh. This study was designed to assess how teak monoculture has impacted the soil properties in Bangladesh. Multiple linear regression and correlation matrices were estimat...Teak plantations date back to 1871 in Bangladesh. This study was designed to assess how teak monoculture has impacted the soil properties in Bangladesh. Multiple linear regression and correlation matrices were estimated to evaluate these impacts. The means of soil physicochemical properties were compared across various attributes of the plantations. Older plantations accumulated more organic carbon in the soils than the younger plantations. Excessive removal of litter from the forest floor resulted in reduced levels of N, P, K, and other nutrients in the soils. Since bulk density was continuously decreasing deeper into the soil, the penetration of mineral nutrients into the soil was low. Furthermore, moisture content in the topsoil was significantly lower than that in the bottom layers due to the exposed and dry condition of the forest floor under teak plantations. For improving depleted teak plantation soils, teak could be planted with other tree species rather than just in monocultures. In addition, the forest floor could be enriched with leguminous herbs and shrubs to improve soil health in these plantations.展开更多
基金Intercooperation,Agroforestry Improvement Project and Village and Farm Forestry Project (IC-VFFP, AFIP) Rajshahi (Funded by Swiss Agency for Development Cooperation,SDC)
文摘Allelopathic effects of different doses of Eucalyptus camaldulensis leaf litters were investigated through an experiment in the green house of Institute of Forestry and Environmental Sciences, Chittagong, Bangladesh. Three popular agricultural crops： Falen （Vigna unguiculata）, Chickpea （Cicer arietinum）, Arhor （Cajanus cajan） and two widely used plantation trees： Sada koroi （Albizia procera） and Ipil ipil （Leucaena leucocephala） were selected as bioassay species. Experiment was set on tray at room temperature 27℃. The effects of different doses of leaf litter extracts were compared to the control. Results suggest that leaf litters of E, camaldulesis induced inhibitory effects, It was also found that the effect depend on concentration of extract and litterfall, type of receiver species. Higher concentration of the materials had the higher effect and vice versa. Though all the bioassay species were suppressed some of them showed better performance. Vigna unguiculata, Cicer arietinum are recommended in agroforestry based on this present Experiment output. In mixed plantation, Leucaena leucochephala is a better choice while compared to Albizia procera.
文摘An experiment was conducted to assess the effect of leaf litter of Leucaena leucocephala on two forest crops Sada koroi （Albizia procera）, Ipil ipil （L. leucocephala） and three agricultural crops Falen （Vigna unguiculata）, Chickpea （Citer arietinum） and Arhor （Cajanus cajan） in the nursery of the Institute of Forestry and Environmental Sciences, Chittagong University, Bangladesh, in a Randomized Block Design. Results suggested that leaf litters ofL. leucocephala induced inhibitory effects on germination and growth of bioassay. It was also found that the effect depended on concentration of extract and litterfall, type of receptor species. Higher concentration of the materials had the higher effect and vice versa. Growth response of receptor crops varied with the variation of leaf litter application. The study revealed that application of low-dose leaf litter specially litter of 10 g·m^-2 had stimulating effect on shoot growth of C. arietinum, Vunguiculata and A. procera. While in all other cases significant inhibitory effect was observed and it was significantly increased with the increase of leaf litter application. However, the trend of inhibition was uneven with treatments. Root growth was found to be more affected than shoot growth.
文摘Triple Super Phosphate, TSP fertilizer, was applied @ 80 kg·ha^-1 as the source of phosphorous on six months old polybag seed- lings of Albizia chinensis, Albizia saman and Pongamia pinnta in nursery beds in Bangladesh. The effects of P-fertilizer on seedling growth and nodulation were comparcd to that of seedlings grown in unfertilized soil or in control at different harvesting intervals. The study revealed that, seedling growth was enhanced significantly with the application of P-fertilizer. The growth was found more pronounced in cases of A. saman and P. pinnata, whereas it was not noticeable and showed depressed growth in case of A. chinensis. The study also suggests that nodulation in terms of nodule number and size was also increased significantly with P-fertilization except in case ofP. pinnata, where higher harvesting intervals lowered the nodulation performance of that species
文摘An experiment was conducted to observe the inhibitory effects of the leaf extracts derived from Albizia lebbeck （L.） Benth. On germination and growth behavior of some popular agricultural crops （receptor） of Bangladesh. Experiments were set on sterilized petridishes with a photoperiod of 24 h at room temperature of 27-30℃. The effects of the different concentrations of aqueous extracts were compared to distil water （control.）. The aqueous extracts of leaf caused significant inhibitory effect on germination, root and shoot elongation and development of lateral roots of receptor plants. Bioassays indicated that the inhibitory effect was proportional to the concentrations of the extracts and higher concentration （50%-100%） had the stronger inhibitory effect whereas the lower concentration （10%-25%） showed stimulatory effect in some cases. The study also revealed that, inhibitory effect was much pronounced in root and lateral root development rather than germination and shoot growth.
文摘An experiment was conducted to understand the growth inhibitory effects of aqueous extracts derived from Lantana camara L. （a globally recognized invasive alien weed） on six popular agricultural crops of Bangladesh. The test was conducted in sterilized petridishes with a photoperiod of 24 hours and an average temperature of 29℃. The effect of different concentrations ofL. camara leaf extracts were recorded and compared with control （i.e., distil water）. Result showed different concentrations of aqueous leaf extracts caused significant inhibitory effect on germination, root and shoot elongation and development of lateral roots of receptor crops. Bioassays also indicated that the inhibitory effect was proportional to the concentrations of the extracts and higher concentration had the stronger inhibitory effect whereas the lower concentration showed stimulatory effect in some cases. The inhibitory effect was much pronounced in root and lateral root development rather than shoot and germination.
文摘The effects of different inorganic fertilizers （Urea and Triple Super Phosphate （TSP）） on seedling growth and nodulation capabilities of four agroforestry tree species （Albizia chinensis, A. saman, Acacia nilotica and Sesbania sesban） were compared. The nodulation of these seedlings were treated with different fertilizer treatments （at the rate of urea 40 kg·hm^-2, urea 80 kg·hm^-2 TSP 40 kg·hm^-2, TSP 80 kg·hm^-2, （urea＋TSP） 40 kghm 2 and （urea＋TSP） 80 kg·hm^-2） after one month of seed germination. The results revealed that the seedling growth was enhanced significantly with moderate fertilizer treatment. In some cases, the higher levels of fertilizers reduced the seedling growth. The study also revealed that the nodulation in nodule number and size was significantly inhibited by the application of N fertilizer （Urea）, while it was increased significantly with the application of P fertilizer （TSP）. This study improved our understanding and provided insights that would be useful to the farmers in their efforts to amend the soil with inorganic fertilizers in order to enhance plant growth and biological nitrogen fixation.
文摘We focused on key aspects of forest governance for biodiver- sity conservation in implementing new climate change policies. The national forest institutions must be adaptive to identify the existing pitfalls of prior conservation policies to take advantage of new climate change policies. Strengthening roles and technical capacity of national institutions for systematic biodiversity monitoring and carbon stock assessment is required in developing and least developed countries. Community participation needs careful analysis to ensure equitable ac- cess of particular social groups to local decision-making processes and to sustain optional livelihoods. The livelihood options around forest reserves or protected areas must be taken into account to enhance forest-based adaptation.
文摘An experiment was conducted to assess the effect of Phosphorous （P） fertilizer （i.e. TSP or triple super phosphate @ 80 kg/hm^2） on seedling growth and nodulation capabilities of three potentially important agroforestry tree species （Acacia auriculiformis, Albizia lebbeck and Albizia procera） of Bangladesh. The study was conducted in nursery beds with six-month-old polybag seedlings ofA. auriculiformis, A. lebbeck and A. procera. The effects of P fertilizer on seedling growth and nodulation were compared with that of the seedlings grown in control （i.e. unfertilized soil）. The observations revealed that the seedling growth was enhanced significantly with the application of P fertilizer. The growth was found more pronounced in A. auriculiformis, whereas it was not apparent and shows depressed growth in case ofA. lebbeck. The study also suggests that the nodulation in terms of nodule number and size was also increased significantly with the application of P fertilizer.
文摘Teak plantations date back to 1871 in Bangladesh. This study was designed to assess how teak monoculture has impacted the soil properties in Bangladesh. Multiple linear regression and correlation matrices were estimated to evaluate these impacts. The means of soil physicochemical properties were compared across various attributes of the plantations. Older plantations accumulated more organic carbon in the soils than the younger plantations. Excessive removal of litter from the forest floor resulted in reduced levels of N, P, K, and other nutrients in the soils. Since bulk density was continuously decreasing deeper into the soil, the penetration of mineral nutrients into the soil was low. Furthermore, moisture content in the topsoil was significantly lower than that in the bottom layers due to the exposed and dry condition of the forest floor under teak plantations. For improving depleted teak plantation soils, teak could be planted with other tree species rather than just in monocultures. In addition, the forest floor could be enriched with leguminous herbs and shrubs to improve soil health in these plantations.
