Measuring marginal willingness to pay using conjoint analysis and developing benefit transfer functions in various Asian cities

We need a consistent methodology to measure the co-benefits of climate change mitigation across Asian countries. This study chose a strategy of modifying the Japan-specific life-cycle impact assessment method based on endpoint modeling (LIME) for wider application across countries. LIME has two dimensions. First, it is an environmental science that links the cause-and-effect chain. Second, it is an environmental valuation that weighs four endpoint damages in monetary terms through a conjoint analysis that is derived from an Internet-based questionnaire survey. This article describes the modification of the methodology for application of the conjoint analysis to weigh environmental impacts. We approached the investigation as follows. First, we conducted Internet surveys to measure marginal willingness-to-pay (MWTP). We used a sample of 112 respondents in their 20 s to 40 s, divided equally between men and women, in 11 cities across China, India, and Southeast Asia. The results obtained showed clear statistical significance and were comparable across the cities. Second, we attempted to develop functions (called benefit transfer functions) to simplify the measured MWTP in order to apply it across different Asian countries. The functions were derived through a stepwise meta-analytic method, a type of multiple regression analysis whose independent variable was MWTP and dependent variables were attributes of both respondents and surveyed cities. The functions showed that coal consumption and percentage of nature reserve were dependent variables. Then, the MWTPs estimated from the functions were compared with the measured MWTP for transfer error, which is calculated by the absolute value of the difference between the estimated value and the measured value divided by the latter. The transfer error was below 50% in about 90% of the 44 results (a combination of four endpoints and 11 cities), implying that the developed functions were statistically significant.     

Response surface method for modeling the removal of carbon dioxide from a simulated gas using water absorption enhanced with a liquid-film-forming device

This paper presents the results from using a physical absorption process to absorb gaseous CO_2mixed with N_2using water by producing tiny bubbles via a liquid-film-forming device(LFFD)that improves the solubility of CO_2in water.The influence of various parameters—pressure,initial CO_2concentration,gas-to-liquid ratios,and temperature—on the CO_2removal efficiency and its absorption rate in water were investigated and estimated thoroughly by statistical polynomial models obtained by the utilization of the response surface method(RSM)with a central composite design(CCD).Based on the analysis,a high efficiency of CO_2capture can be reached in conditions such as low pressure,high CO_2concentration at the inlet,low gas/liquid ratio,and low temperature.For instance,the highest removal efficiency in the RSM–CCD experimental matrix of nearly 80%occurred for run number 20,which was conducted at 0.30 MPa,CO_2concentration of 35%,gas/liquid ratio of 0.71,and temperature of 15°C.Furthermore,the coefficients of determination,R~2,were 0.996 for the removal rate and 0.982 for the absorption rate,implying that the predicted values computed by the constructed models correlate strongly and fit well with the experimental values.The results obtained provide essential information for implementing this method properly and effectively and contribute a promising approach to the problem of CO_2capture in air pollution treatment.     

Elementary budget of stag beetle larvae associated with selective utilization of nitrogen in decaying wood

Wood degradation by insects plays important roles for the forest matter cycling. Since wood is deficient in nitrogen compared to the insect body, wood-feeding insects need to assimilate the nitrogen selectively and discard an excess carbon. Such a stoichiometric imbalance between food and body will cause high metabolic cost; therefore, wood-feeding insects may somehow alleviate the stoichiometric imbalance. Here, we investigated the carbon and nitrogen budgets of the larvae of stag beetle, Dorcus rectus, which feed on decaying wood. Assimilation efficiency of ingested wood was 22%, and those values based on the carbon and nitrogen were 27 and 45%, respectively, suggesting the selective digestion of nitrogen in wood. Element-based gross growth efficiency was much higher for nitrogen (45%) than for carbon (3%). As a result, the larvae released 24% of the ingested carbon as volatile, whereas almost no gaseous exchange was observed for nitrogen. Moreover, solubility-based elementary analysis revealed that the larvae mainly utilized alkaline-soluble-water-insoluble fraction of wood, which is rich in nitrogen. Actually, the midgut of the larvae was highly alkaline (pH 10.3). Stag beetle larvae are known to exhibit coprophagy, and here we also confirmed that alkaline-soluble-water-insoluble nitrogen increased again from fresh feces to old feces in the field. Stable isotope analysis suggested the utilization of aerial nitrogen by larvae; however, its actual contribution is still disputable. Those results suggest that D. rectus larvae selectively utilize alkaline-soluble nitrogenous substrates by using their highly alkaline midgut, and perhaps associate with microbes that enhance the nitrogen recycling in feces.     

Suppression of arsenic leaching from excavated soil and the contribution of soluble and insoluble components in steel slag on arsenic immobilization

Environmental Science and Pollution Research - A huge amount of soil is excavated by tunnel and road construction projects in urban, coastal, and mountainous regions. These projects enable the...     

Predicting the particle size distribution of fine-grained and sandy soils using deep learning for classifying recovered soils separated from tsunami deposits

Journal of Material Cycles and Waste Management - Disaster wastes, particularly those generated in the tsunami, comprise soil and sediments, and recovered soil is yielded through treatment such as...     

Inactivation effect of pressurized carbon dioxide on bacteriophage Qβ and ΦX174 as a novel disinfectant for water treatment

The inactivation effects of pressurized CO2 against bacteriophage Qβ and ΦX174 were investigated under the pressure of 0.3–0.9 MPa, initial concentration of 107–109PFU/mL, and temperature of17.8°C–27.2°C. The optimum conditions were found to be 0.7 MPa and an exposure time of 25 min. Under identical treatment conditions, a greater than 3.3-log reduction in bacteriophage Qβ was achieved by CO2, while a nearly 3.0 log reduction was observed for phage ΦX174. The viricidal effects of N2O(an inactivation gas with similar characteristics to CO2), normal acid(HCl), and CO2 treatment with phosphate buffered saline affirmed the chemical nature of CO2 treatment. The pumping cycle, depressurization rate, and release of intracellular substances caused by CO2 were its viricidal mechanisms. The results indicate that CO2 has the potential for use as a disinfectant without forming disinfection by-products.     

Toxicity test using medaka (Oryzias latipes) early fry and concentrated sample water as an index of aquatic habitat condition

The aim of the present study was to show a relationship between toxicity of 100-fold concentrated water and aquatic habitat conditions. Environmental waters are 100-fold concentrated with solid-phase extraction. Medaka early fry was exposed in these waters for 48 h. The number of death and disorder was counted at 1, 2, 3, 6, 12, 24, and 48 h; toxicity was expressed using inverse median effect time and median lethal time (ET (50)(-1), LT (50)(-1)). Average score per taxon (ASPT) for benthic animals and Index of Biotic Integrity (IBI) for fish were applied as indices of aquatic habitat conditions. The results of toxicity test were compared using ASPT and IBI. The different levels of toxicity were detected in the seawater of Japan. At the Husino River area, toxicity cannot be detected. In rivers, high toxicity appeared at urban districts without sewerage. By Spearman coefficient, the relationship between toxicity and high biochemical oxygen demand (BOD) were obtained. BOD household wastewater contains hydrophobic toxic matters; otherwise, seawater in industrial area does not show clear relationship between toxicity and chemical oxygen demand. Gas chromatography to mass spectrometry simultaneous analysis database may give an answer for the source of toxicity, but further test is required. Ratio of clear stream benthic animal sharply decreased over 0.25 of LT (50)(-1) or 0.5 of ET (50)(-1). Tolerant fish becomes dominant over 0.3 of LT (50)(-1) or 0.5-1.0 of ET (50)(-1). By Pearson product-moment correlation coefficient, correlation coefficient between toxicity and ASPT was obtained at -0.773 (ET (50)(-1)) and -0.742 (LT (50)(-1)) at 1 % level of significance with a high negative correlation. Toxicity (LT (50)(-1) ) has strong correlation with the ratio of tolerant species. By Pearson product-moment correlation coefficient, correlation coefficient between toxicity and IBI obtained were -0.155 (ET (50)(-1)) and -0.190 (LT (50)(-1)) at 1 % level of significance and has a low or no correlation between toxicity and IBI. Even with low toxic environmental waters, toxicity test using 100-fold concentrated and medaka early fly could detect acute toxicity. The detected toxicity seemed to limit the inhabiting aquatic species in the water body.     

Effect of aging time on the availability of freshly precipitated ferric hydroxide to coastal marine diatoms

Cell growth and iron uptake of the coastal marine diatoms Chaetoceros sociale and Thalassiosira weissflogii were studied in the presence of short-aged amorphous ferric hydroxide (am-Fe(III)) media. These were prepared by aging for 1 day, 3 days, and 3 weeks after adding a small amount of ferric iron acidic stock solution to autoclaved filtered seawater and were experimentally measured in culture experiments at 10°C for C. sociale and 20°C for T. weissflogii. The order of cell yields for both species was: 1-day aged am-Fe(III) >3-day aged am-Fe(III) >> 3-week aged am-Fe(III) media. The iron uptake rates by C. sociale during 0–1 day in 1 day and 3-day aged am-Fe(III) media were about two-thirds and one-fourths, respectively, lower than that in the direct Fe(III) input medium containing C. sociale into which an acidic Fe(III) stock solution was added directly. The longer aging time of am-Fe(III) in media results in reducing the supply of bioavailable iron in the media by the slower dissolution rate of am-Fe(III) with the longer aging time. These results suggest that the chemical and structural changes of freshly precipitated amorphous ferric hydroxide with short aging time affect their ability, such as iron solubility and dissolution rate to supply bioavailable iron for the phytoplankton growth. The chemical and structural conversion of solid iron phases with time is one of the most important processes in changing the supply of available iron to marine phytoplankton in estuarine and coastal waters and in iron fertilization experiments.     

液相色谱-大气压光电离/质谱测定鱼肉中的氯霉素残留

用液相色谱 大气压光电离质谱开发出测定鱼肉中氯霉素的方法 .为优化大气压光电离子 (APPI)考察了几种离子源参数 .使用该参数 ,得到了简单的质谱图和对应于 [M H]- 的强信号 .样品用乙酸乙酯萃取并挥发至干 ,然后用乙腈和正己烷通过液液分配进行纯化 .对于加入量为 0 1— 2ng·g- 1 的样品 ,小鲱肉和比目鱼肉中氯霉素的平均回收率分别为 89 3%— 1 0 2 5 %和 87 4%— 94 8% .小鲱肉和比目鱼肉中氯霉素残留的检测极限 (信噪比 =3)分别为 0 2 7ng·g- 1 和 0 1 0ng·g- 1 .     

Examining farmland applications of composted biosolid wastes depending on nutrient balance in soils

This study emphasizes nutrient balance of soils in the farmland application of composted biosolid wastes. The loading rates of plant nutrients following the compost application to farmland in Japan were estimated and compared with the nutrient uptake of agricultural plants. Results show that the current compost application in Japan can meet the requirements of agricultural plants for plant nutrient Ca, except for K, Mg, P, Fe, Mn, Cu, and Zn. The compost application could realize the safe disposal of biosolid wastes and the effective recycling of plant nutrients in composts to soils without causing heavy metal accumulation. The application manner of composts affects the heavy metal accumulation in farmlands. Field examination indicates that the excessive compost application has led to the heavy metal accumulation in compost-amended farmlands. Measuring the nutrient balance in compost-amended farmlands is well suitable for explaining the accumulation of heavy metals, such as Cu and Zn.