No abstract

This paper studied the chemical composition of cultivated 3, 4 and 5 year-old highland bamboo (Y. alpina) which were classified into three position (top, medium and bottom) to determined the main compositions especially cellulose, lignin, extractive and ash content. From all culms representative samples were converted to the required size of wood chips to prepared sample for chemical testing. Then the specimens prepared from bottom, middle and top portions for the three ages were used to determine the chemical properties in accordance to American Society for Testing and Materials (ASTM) standards except for cellulose test determined according to Kurschner and Hoffer method. All parameters in the experiment were expressed by percent based on dry basis. From this research, we have found small but significant increases in mean cellulose content from the base to the top of the culm at all three ages. The lignin content in Y. alpina species of bamboo is in the ranged of 23.04 to 30.03%. The mean values of the chemical constituents in 3, 4 and 5- year-old culms were 51.83, 54.94 and 49.78% for cellulose content, 28.28, 24.99 and 24.53% for lignin content, 7.8, 10.09, and 9.54% for alcohol-toluene extractive, respectively. In general, the comprehensive knowledge of the chemical components in the bamboo species will facilitate the use of the materials in the forestry industrial sector and help to enhance their utilization in the chemical and bio-chemical related industry.

Biomass based traditional energy has been the main energy supply in Ethiopia. Efforts are being made to shift to modern bioenergy utilization but the level of contribution of modern bioenergy to the total energy supply of the country’s supply is not computed. In this synthesis we described the contribution of bioenergy to modern energy utilization in the country. Data used here was retrieved from the country’s official reports and published literatures. Access to modern cooking services in the country was particularly focused on and both biogas feedstock productivities and biogas processing efficiencies were calculated. Herfindahl Index (HI) was calculated to observe the change in the diversity of the total primary energy supply due to bioenergy in the country. Results indicated that only a few households, 10%, had access to modern bioenergy services. Less than 0.10% of households have a biogas digester. The HI values showed the low diversity of the energy supply and the very limited contribution of modern bioenergy. This synthesis indicated that the contribution of modern bioenergy to the energy supply of the country is very low. Very low difference was observed between Herfindahl Indexes with and without considering modern bioenergy in the total primary energy supply (TPES) of the country is also found to be insignificant. Results found indicated lower diversity of the energy supply of Ethiopia and very limited contribution of modern bioenergy to the diversity and security of the energy supply.

This paper studied the chemical composition of cultivated 3, 4 and 5 year-old highland bamboo (Y. alpina) which were classified into three position (top, medium and bottom) to determined the main compositions especially cellulose, lignin, extractive and ash content. From all culms representative samples were converted to the required size of wood chips to prepared sample for chemical testing. Then the specimens prepared from bottom, middle and top portions for the three ages were used to determine the chemical properties in accordance to American Society for Testing and Materials (ASTM) standards except for cellulose test determined according to Kurschner and Hoffer method. All parameters in the experiment were expressed by percent based on dry basis. From this research, we have found small but significant increases in mean cellulose content from the base to the top of the culm at all three ages. The lignin content in Y. alpina species of bamboo is in the ranged of 23.04 to 30.03%. The mean values of the chemical constituents in 3, 4 and 5- year-old culms were 51.83, 54.94 and 49.78% for cellulose content, 28.28, 24.99 and 24.53% for lignin content, 7.8, 10.09, and 9.54% for alcohol-toluene extractive, respectively. In general, the comprehensive knowledge of the chemical components in the bamboo species will facilitate the use of the materials in the forestry industrial sector and help to enhance their utilization in the chemical and bio-chemical related industry.