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For Japanese renewable energy policy, we propose the introduction of solar power generation in agricultural land, as a policy with great potential effects on energy independence, creation of employment, contribution to local economies, etc. Our estimate demonstrated that only a relaxation of regulations, without spending taxpayer’s money, would create one million jobs, improve energy independence by 30% of total power generation in Japan, and help economic growth by 3% of annual GDP.

Seasonal variations in abundance of Oithonidae copepods were investigated from zooplankton samples collected weekly to biweekly at the two different stations in the Kagoshima Bay, southern Japan. Oithonidae copepods showed the similar pattern between the two stations, which they occurred abundantly from April to September and decreased below 10 inds./m3 during October to January. Abundance of each developmental stage was simultaneously fluctuated, indicating that it was a short development time. Nauplii, young copepodites and adult females were found over the study period, whereas adult males disappeared in some sampling periods between October and March. During this season, adult females and nauplii were at predominant stages. Females comprised more than 70% of adults, showing a longer life span than males. These results suggest that the decline of their abundance is caused by low rates of egg production, copepodite recruitment from nauplii and/or survival of young copepodites during the cold season although they reproduce throughout the year.

博士（理学） ; 日本大学

After the nuclear accident at the Fukushima No. 1 nuclear power plant, electric energy by thermal power generation using natural gas or coal increased to make up for the decrease of electric energy produced by nuclear power generation. It is well known that greenhouse gas, such as carbon dioxide, increases with consumption of fossil fuels. Therefore, enhancement of renewable energy including solar, wind, geothermal, hydro and biomass is anticipated. Among the forms of renewable energy, energy from biomass is available in cities and the suburbs. Biogas results from anaerobic fermentation of wet biomass, such as sludge, food waste and agricultural waste. Considering the case studies about methane fermentation in a regional independent society, the Tama region around Tokyo possesses potential for mixed methane fermentation with plant biomass (paper, food waste and agricultural waste) and sludge. When the mixed methane fermentation is carried out in Tama region, establishment of a regional independent, sustainable and recycling-based society with low carbon will become possible.

Internal combustion engine has been required high efficiency and low pollution from increase of energy demand and environmental problem. Therefore, it has been attracted attention to use diesel engine that has superior environmental performance compared with gasoline engine and low environmental loading fuel from biomass as an alternative fuel. Diesel engine has low fuel consumption and CO2 emission compared with gasoline engine, therefore, sales of new cars over 50% are diesel in Europe. On the other hand, there is a strict regulation against emission such as NOx and PM in many countries, therefore, further performance improvement is needed. As a fuel from biomass, bioethanol made from plant and Bio Diesel Fuel (BDF) made from oil and fat has been using. Therefore, effects for combustion characteristics of diesel engine have been investigated by using alcohol-coconut-light oil blend fuels.The main results are as follows;1) NOx emission is reduced by using alcohol-light oil and alcohol-coconut-light oil blend fuels at any load conditions. 2) HC and CO emission are reduced by using multicomponent alcohol fuel and alcohol-coconut-light oil blend fuels at low load condition. 3) CO2 emission and Net Thermal Efficiency are same level as light oil by using alcohol-light oil and alcohol-coconut-light oil blend fuels.

地球環境研究論文集 第20巻 ; インドネシアでは, 国内温室効果ガス(GHG)排出量の約67%が農業・森林・土地利用変化(AFOLU)に由来している. 排出削減効果の定量的な評価および高い削減効果をもつ対策の特定は重要である. 我々は, AFOLU排出削減評価モデル(AFOLUB)を開発したが, これを用いAFOLU部門におけるGHG排出緩和のための具体策を提示した. GHG排出量を推計した結果, 2030年において対策を実施しない場合AFOLU部門に由来する排出量は2000年比2.5倍の1.7GtCO2eqになることが示された. その75%は泥炭地の排水・酸化による. また, 2030年, GHG排出削減のための追加的許容費用10USD/tCO2eq下において農畜産業部門では2000年排出量比45%に相当する33MtCO2eq/年の削減が見込まれ, うち11MtCO2eq/年は水田での水管理および農閑期の稲わらのすき込みによる効果であった. 一方, 森林・土地利用変化部門については10億USD(2005～2050年)の資金制約下において, 長期的な視点での対策策定を行えば, 自然回復の強化, 再植林, 森林伐採の減少により, 2050年まで平均して約829MtCO2eq/年の削減効果が示された. これは2000年時点のLULUCF部門の排出量の1.2倍, エネルギー部門の排出量の約2.6倍に相当する. ; In Indonesia, in 2000 around 67% of domestic GHG emissions derives from Agriculture, Forestry and Other Land Use (AFOLU). It is important to evaluate quantitatively mitigation potentials and to specify countermeasures with large mitigation potentials. Using the AFOLU Bottom-up Model, we estimated GHG emissions and mitigation in AFOLU sectors based on a future scenario, harvested area of crops, number of livestock and land use change. Based on the analysis, in 2030 we found that GHG emissions in AFOLU sectors are expected to increase by 2.5 times at the 2000 level in the BaU case. 75% of emission in 2030 derives from peat land drainage. Under 10USD/tCO2eq of allowable abatement costs, 33MtCO2eq/year of GHG emissions can be reduced in agriculture, which corresponds approximately to 46% of agricultural emissions in 2000. Midseason drainage in rice paddies, fall incorporation of rice straw and high efficiency fertilizer application are expected to reduce around 11MtCO2eq/year. For the Land Use, Land-Use Change and Forestry sectors, enhanced natural regeneration, reforestation and avoid deforestation will be the most cost-effective countermeasures considering cumulative mitigation potentials up to 2050.

Bamboo powder (particle size 0.2 mm) and three cube-shaped woods (1 mm, 2 mm and 3 mm) were carbonized in the superheated steam (SHS) combined with far infrared heating (FIH), and the effect of sample size on carbonization rate was investigated. Carbonization temperature was adjusted at 270, 280, 290, and 300°C by regulating the SHS temperature at 180°C with the FIH temperatures at 375, 400, 425, and 450°C. Carbonization energies for the combined treatment were also compared with those for the carbonization treatment in SHS alone at 255, 265, 275, and 285°C. The generation rate of the SHS was the same for both carbonization treatments. The carbonization rate of each sample obeyed a first order reaction rate equation. Average values of the activation energy for the combined treatment of SHS with FIH and for the treatment in SHS alone were 137 kJ/mol and 149 kJ/mol, respectively. These values were almost the same as the activation energies for thermal decomposition of starch and cellulose under nitrogen gas. The relationship between the logarithmic values of the sample sizes and those of the carbonization rate constants was expressed as a linear curve at each carbonization temperature. Compared with the carbonization in the SHS alone, the combine treatment of SHS and FIH was much easier to make the carbonization apparatus in high carbonization temperature conditions with small additional heat. The higher the FIH temperature, the smaller the carbonization energy was obtained, because of shortening the carbonization time significantly. ; 竹粉(粒径0.2mm)および試料サイズを1mm, 2mm, 3mm角に揃えた木片を遠赤外線加熱(FIH)を付加した過熱水蒸気(SHS)処理で炭化処理し, 試料サイズの違いが炭化速度に及ぼす影響について調べた. SHS温度180℃にFIH温度375, 400, 425, 450℃を付加して, 炭化温度を270, 280, 290, 300℃に調整した. また, SHS温度255, 265, 275, 285℃のSHS単独処理の場合とFIH付加に要する炭化エネルギを比較した. 2つの炭化処理で過熱水蒸気生成速度は同じとした. 炭化速度は, どの試料においても一次反応速度式に従った. 活性化エネルギの平均値は, 遠赤外線加熱を付加した過熱水蒸気処理の場合は137kJ/mol, 過熱水蒸気単独処理の場合は149kJ/molであった. これらの値は, 窒素ガス中での澱粉やセルロースの熱分解反応の活性化エネルギの文献値とほぼ一致した. 試料サイズと炭化速度定数の関係は, いずれの炭化温度でも両対数紙上で直線で表された. SHS処理にFIHを付加した場合には, ...

During the research of "WEST-COSMIC (Western Pacific Environment Assessment Study on C02 Ocean Sequestration for Mitigation of Climate Change)", vertical distribution of plankton community structure was studied at 39°N, 147°E (down to 2000 m) and 44°N, 155°E (down to 4000 m) in the western North Pacific Ocean. Plankton community was largely divided into four major groups (bacteria, phytoplankton, protozooplankton, and metazooplankton) and their biomass were expressed carbon unit by measuring volume and using volume-carbon equations. Total plankton biomass in the water column was 13,873 mgC m^-2 at 39°N, 147°E and 29,772 (daytime) to 32,780 (nighttime) mgC m^-2 at 44°N, 155°E. The water column was divided into three strata: epipelagic (0-200 m); mesopelagic (200-1000 m); bathypelagic (>1000 m), and their contribution to total water-column plankton biomass was 33-38% (epipelagic), 33-37% (mesopelagic), and 25-34% (bathypelagic), respectively. In the epipelagic, the contribution of four major taxa in plankton biomass was nearly equal (ratios of four taxa; bacteria, phytoplankton, protozooplankton, and metazooplankton to the total biomass were 18-25%, 29-38%, 6-25%, and 17-40%, respectively). Below the epipelagic zone, phytoplankton biomass was decreased rapidly (1-2% of total biomass). In the mesopelagic zone, metazooplankton was the most dominated (60-85%) and bacteria was the second (12-28%). These two taxa dominated also in the bathypelagic zone，but the contribution of metazooplankton was decreased (43-47%) while that of bacteria was increased (41-47%). Constantly，the biomass of each taxon (mgC m^-3) was decreased with depth, and the relationship between carbon biomass and depth was expressed by regression model: log10Y = log10a＋b×log10X (or Y=a×X^b), where Y is the biomass (mgC m^-3), X is the depth (m), and a and b are fitting constants. Most of the taxa fitted to the regression well, and the slope (b) of regression was different between taxa: -0.56 for bacteria, -1.32 to -1.34 for phytoplankton, -0.95 for ...