Municipal solid waste composition and food loss reduction in Kyoto City

For 35 years, Kyoto City has conducted detailed household waste composition surveys under the guidance of Kyoto University by dividing household waste into approximately 400 categories. In addition, the city has conducted detailed composition surveys of commercial waste generated by businesses. These surveys show that food loss accounts for approximately 40% of total waste, of which leftovers and untouched food account for about 40% in both households and business facilities. Consequently, the annual generation of household and commercial food loss is estimated at about 30,000 tons. Various efforts have been made to reduce waste, including food loss, but further reduction in environmental burden is needed. Thus, Kyoto City revised the ordinance for waste reduction, and in March 2015, formulated a new municipal waste management plan. The plan not only includes the 2Rs (reduce, reuse), but also, for the first time in Japan, sets quantitative targets for reducing food loss. Kyoto City must ensure that the necessary waste reduction measures are clearly explained to the residents and business operators. To ensure that this plan is successful, it is important to clarify concrete actions that residents and business operators should implement, along with their effects.     

Simplified Fabrication of Optically Transparent Composites Reinforced with Nanostructured Chitin

Optically transparent films reinforced with micro to nano scale chitin particles were successfully developed in this study. Chitin composites based on micro scale particles which are larger than the optical wavelength do not cause light scattering provided that chitin particles are composed of nano structure networks which allow monomer impregnation and polymerization. This could lead a simplified process for fabricating transparent composites. The composites reinforced by the chitin micro particles not only retained the transparency of the plastic but also helped the effectiveness of its co-efficient of thermal expansion as similar to chitin nanofibers. Furthermore, chitin nanofibers transparent films are thermally stable against temperature as high as 200 °C for a long period of time. This could lead to number of important commercial applications, and is a significant move towards the sustainable utilization of marine bio-resources.     

Quantitative analysis of perfluorinated chemicals in media for in vitro fertilization and related samples

The actual standard in vitro fertilization (IVF) protocol recommends an overnight gamete co-incubation. All of the culture media used for human IVF are supplemented with serum or albumin. In the present study, we determined the concentrations of perfluorinated chemicals (PFCs) in IVF media (IVFM) and related samples by liquid chromatography with tandem mass spectrometry (LC/MS/MS). The results indicated that the concentrations of PFOS and PFOA in the protein source were higher than those in the IVFM samples. Compared with human plasma concentrations of PFCs, PFCs in all of the IVFM samples, such as PFBS, PFHxS and PFOA, were either not detected or present at only trace levels, even when protein source was added. LC/MS/MS could be used to determine PFCs in IVFM samples in future studies of the effects of PFC exposure on intrauterine insemination.     

Greenhouse gas emissions from biogenic waste treatment: options and uncertainty

A simplified life cycle assessment was conducted to estimate greenhouse gas (GHG) emissions and energy production from each component of biogenic waste treated in an open dumping site, and by composting, anaerobic digestion, and incineration employed with additional options. The impact of uncertainties and sensitivities of the parameters in the treatment methods were investigated. We conducted a sensitivity analysis to identify the most sensitive parameters, and we discussed the relationship between uncertainty and sensitivity. Our results revealed that the moisture content of food waste and the biomass-derived carbon and methane concentration of the landfill gas of biogenic waste subjected to open dumping are the most sensitive parameters across all the treatment methods. The net GHG emissions from food waste treated in an open dumping site ranged over ten times (0.30 ? 3.67 Gg CO₂ eq/Gg). In addition, by employing additional options for the open dumping site, including soil cover, a landfill gas collection system, shifting to a semi-aerobic condition, and energy conservation by using a gas engine, we found that the net GHG emissions could be reduced by 10, 27.9, 37.4 %, and up to 56.7 %, respectively. Shifting to a semi-aerobic system is the most effective method for reducing GHG emissions, followed by landfill gas collection.     

Optimization of compost fermentation of glycerol by-product discharged from biodiesel fuel production process

Development of a cheap system for reuse of glycerol by-product discharged from the biodiesel fuel (BDF) production process is needed in parallel with development of a low-cost BDF production system. In this article, optimization of compost fermentation of glycerol by-product was studied. The type and amount of additive nitrogen source was studied, and good utilization of glycerol was observed when 0.5 g of urea was added to a mixture of 625 g dry sawdust, 25 g of microbial seed, and 50 g of glycerol by-product. To achieve efficient compost fermentation, repeated batch fermentation was applied and five batch cultures were repeated. Although the pH level and nitrogen and water contents were maintained at suitable levels for microbial growth, the glycerol consumption rate gradually decreased with accumulation of oily compounds in the compost. Finally, a material cost evaluation of the compost fermentation proposed in this study was performed. The total material cost decreased to ￥0.57 /l of BDF when employing an existing compost system for the fermentation process, although sawdust used for mushroom cultivation was used in this study at the very high cost of ￥123 /kg dry sawdust. However, the cost of disposal of the glycerol byproduct as an industrial waste was ￥5.2 /l of BDF produced; therefore, there might be an economical advantage to compost fermentation of glycerol by-product from BDF production.     

Troop size,habitat quality,and home range area in Japanese macaques

Summary The correlation between troop size (N) and home range area (R) is examined in terms of habitat quality with 32 data sets for the Japanese macaque (Macaca fuscata) from its entire distribution range. The habitat quality is represented by the vegetation type and the degree the habitat is disturbed. A proportional relationship is found between N and R when the two major vegetation types (deciduous and evergreen) are discriminated and only the data from relatively undisturbed habitats are considered. This result is discussed in relation to bioenergetics.     

Food nitrogen footprint reductions related to a balanced Japanese diet

Dietary choices largely affect human-induced reactive nitrogen accumulation in the environment and resultant environmental problems. A nitrogen footprint (NF) is an indicator of how an individual’s consumption patterns impact nitrogen pollution. Here, we examined the impact of changes in the Japanese diet from 1961 to 2011 and the effect of alternative diets (the recommended protein diet, a pescetarian diet, a low-NF food diet, and a balanced Japanese diet) on the food NF. The annual per capita Japanese food NF has increased by 55% as a result of dietary changes since 1961. The 1975 Japanese diet, a balanced omnivorous diet that reportedly delays senescence, with a protein content similar to the current level, reduced the current food NF (15.2 kg N) to 12.6 kg N, which is comparable to the level in the recommended protein diet (12.3 kg N). These findings will help consumers make dietary choices to reduce their impacts on nitrogen pollution.