This paper aims to identify the factors determining the adoption of the environmental direct-payment program in Japanese agriculture. The paper takes panel data from Japan's 47 prefectures between 2011 and 2014, the period during which these prefectures adopted the current program of environmental conservation through agricultural subsidies, and conducts a quantitative analysis of how economic and social factors affected the adoption of this system. To account for any unobserved heterogeneity among the prefectures, the analysis applies pooled OLS, a fixed-effects model, and a first difference model in its calculations. The findings reveal that the degree to which the agri-environmental direct-payment program was adopted depends on various factors that differ by prefecture, including subsidy amount per unit of land area, farming conditions, land prices, and the extent of population aging.

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 Integration of anaerobic and aerobic biodegradation is a perspective approach for remediating multiple volatile organic compounds (VOCs). The objective of this study was to elucidate aerobically degrading microorganisms of coexisting VOCs; toluene, benzene, and dichloromethane (DCM) in a microbial consortium with DNA-stable isotope probing, after anaerobically degradation of chlorinated ethylenes. The consortium was added with a ¹³C-labeled VOC and the other two unlabeled VOCs at a concentration of 30 mg/L each. DNA was extracted from the periodically sampled consortia according to degradation degree of the VOCs for 32 days. The DNA extracts were applied to next generation sequencing (NGS) to evaluate bacterial communities in the consortia, and density gradient fractionation was performed to clarify the bacteria that degraded the VOCs. Bacterial 16S rRNA gene amplicons in each fraction were analyzed with terminal restriction fragment length polymorphism (T-RFLP) using HhaI. The NGS confirmed the existence of Pseudomonas and Hyphomicrobium in the consortium. As for the T-RFLP, peaks of normalized DNA (558 bp with HhaI) in the treatment added with ¹³C-toluene shifted toward heavier fractions. The T-RF was derived from relatives of Pseudomonas stutzeri. In the treatment added with ¹³C-benzene, peaks of normalized DNA (201 bp with HhaI) shifted toward heavier fractions. The T-RF was originated from relatives of Pseudomonas alcaligenes. Such peak shifts did not occur in the treatment added with ¹³C-DCM, though Hyphomicrobium similar to a known DCM degrader existed. The results suggested that the bacteria involved in degrading toluene and benzene were inferred to be related species to P. stutzeri and P. alcaligenes, respectively. In sequential anaerobic and aerobic biodegradation, maintaining viability of nitrate-reducing bacteria such as Pseudomonas would be significantly useful for enhancing aerobic degradation of the aromatic compounds.

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 Adequate disaster waste management requires the determination of proper policies including (1) selection of equipment, facilities, and resources necessary for treatment, and (2) securing air space of utilization and/or landfill of treated or recovered materials. Further appropriate policies will possibly be determined if useful data exists regarding type of waste fractions before and after each treatment process, their quantities, and constitutive relations between them, which have never been studied before. In this study, comprehensive analyses were conducted to review the performance of the disaster treatment conducted for the recovery from 2011 East Japan earthquake, based on data of disaster waste treatment obtained in Yamada town and Kuji/Noda area in Iwate prefecture. The data used for these two towns were collected and compiled by a newly developed system implementing information and communication technology (ICT), in which all the necessary data (vehicle number, type of material, mass, date, transportation purpose, etc.) were automatically extracted when loaded vehicle was weighed before and after each treatment, and then integrated into a host computer. “Coefficient of separation” is defined in this study as an index of the relations between mass ratios of fractions before and after treatment. Reasonable values of “coefficients of separation” were obtained for larger-size and smaller-size waste mixtures before treatment, and for burnable fraction, unburnable fraction, recovered soil, and residue after treatment. In addition, change in the obtained coefficients were reasonably reflected by the change in treatment process with time. In conclusion, the obtained values of “coefficients of separation” are considered a useful index to be used in determining disaster waste treatment policy. Application of the proposed system with ICT is also considered effective not only to review the performance after treatment but also to implement an observational method during treatment.

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 The objective of this study was to develop a better understanding of the effects of operational parameters of decanter centrifugation, such as dry solid ratio (DS), sigma value (Σ), and volumetric flow rate of feed (Q_feed), on separation performance, especially corrected cut size (D_50C) and particle recovery to underflow (E_UF), with regard to separating a fine-grained fraction from soil slurry. The sigma value (Σ) represented the area of a settling tank capable of the same separation performance in the gravitational field.
 As a result of this study, following observations were made; 1) the values of E_UF declined in a linear fashion with Q_feed/Σ, 2) the corrected cut sizes (D_50C) increased in proportion to Q_feed/Σ, 3) the value of E_UF declined in a linear fashion with D_50C, 4) D_50C obtained through this experimental study differed significantly from the theoretical values calculated on the basis of the sigma values by assuming free settling. It was inferred that (a) centrifugal separation performance was strongly influenced by hindered settling even if feed slurry was relatively low concentration (11-20%DS), and (b) the smaller the grain size, the larger its percentage of platy and cylindrical particles.

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