Differences in the Spatial Variability Among CO2, CH4, and N2O Gas Fluxes from an Urban Forest Soil in Japan

The spatial variability of carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O) fluxes from forest soil with high nitrogen (N) deposition was investigated at a rolling hill region in Japan. Gas fluxes were measured on July 25th and December 5th, 2008 at 100 points within a 100 × 100 m grid. Slope direction and position influenced soil characteristics and site-specific emissions were found. The CO₂ flux showed no topological difference in July, but was significantly lower in December for north-slope with coniferous trees. Spatial dependency of CH₄ fluxes was stronger than that of CO₂ or N₂O and showed a significantly higher uptake in hill top, and emissions in the valley indicating strong influence of water status. N₂O fluxes showed no spatial dependency and exhibited high hot spots at different topology in July and December. The high N deposition led to high N₂O fluxes and emphasized the spatial variability.     

Developing joint educational programs in sustainability science across different universities: a case study from Japan

The challenge for sustainability educational programs lies in how to imbue students with the strong motivation necessary to move the world in a more sustainable direction. Five universities in Japan have mutually collaborated in the design and development of a unique curriculum and education system for sustainability science since 2008. Specifically, they have developed a common and remote lecture system called the “Frontier of sustainability science” (FSS). This paper discusses the concepts and challenges of FSS and how it was organized to teach students to actively learn how to work with people of various disciplines to realize interdisciplinarity.     

Importance of picocyanobacteria biomass (unicellular,blue-green algae) in the phytoplankton population of the coastal waters off Japan

Picocyanobacteria, which specifically excited the phycobilin pigments by green light, were numerically counted under an epifluorescence microscope in the Kuroshio and the Oyashio between 1 and 9 July 1983, and in coastal waters between 10 and 12 August 1983 off Japan. The fluorescence, and the various morphological and chemical characters of the picocyanobacteria were evaluated by using monospecific strains isolated from the study area. Plasma volume determined on the epifluorescence microscopic photographs was converted into cellular organic carbon using a relation obtained from the isolates. Percentages of the picocyanobacteria biomass in terms of cellular carbon ranged between 8.3 to 79.4% of the total picophytoplankton (<3 m), and between 4.7 to 46.4% of the total phytoplankton. The larger percentages of the picocyanobacteria occurred consistently in low chlorophyll waters.     

Sustainability assessment with time-series scores: a case study of Chinese provinces

Asian nations are currently facing a number of challenges, including environmental degradation and growing societal inequalities, in the course of their rapid economic growth and industrialization. Under such conditions, it is of critical importance to develop appropriate assessment tools with which to comprehensively measure the sustainability status of a region in order to guide its transformation into a sustainable society. This paper proposes a method of sustainability assessment consisting of the three components of environment, resource, and socio-economic with aggregated time-series scores. This method can demonstrate the relative sustainability scores of targeted regions for different time periods, thereby, enabling the comparison of relative sustainability status for different regions over these periods. We carried out a case study of Chinese provinces for the years 2000 and 2005 using the proposed method and confirmed its applicability as the indicative type of sustainability assessment at the regional level, while actually investigating the sustainability status and its chronological changes. The results indicated that aggregate sustainability index scores improved between 2000 and 2005 in most provinces, mainly due to significant improvement in the scores for the socio-economic component, whereas the scores for the environment component deteriorated in some provinces over the study period. Our method proves to be effective in analyzing the relative sustainability status among targeted regions for different time periods in the form of aggregate scores, paving the way for practical applications, such as policy analysis, in the pursuit of a sustainable society.     

Field and laboratory evaluation of the treatment of DNAPL source zones using emulsified zero‐valent iron

Emulsified zero‐valent iron (EZVI) is a surfactant‐stabilized, biodegradable emulsion that forms droplets consisting of a liquid‐oil membrane surrounding zero‐valent iron (ZVI) particles in water. This article summarizes the results obtained during the first field‐scale deployment of EZVI at NASA's Launch Complex 34 (LC34) located on Cape Canaveral Air Force Station, Florida, in August 2002 and presents the results of recent follow‐on laboratory tests evaluating the mechanisms, which contribute to the performance of the technology. The field‐scale demonstration evaluated the performance of EZVI containing nanoscale zero‐valent iron (NZVI) when applied to dense, nonaqueous phase liquid (DNAPL) trichloroethylene (TCE) in the saturated zone. Results of the field demonstration indicate substantial reductions in TCE soil concentrations (greater than 80 percent) at all but two soil boring locations and significant reductions in TCE groundwater concentrations (e.g., 60 percent to 100 percent) at all depths targeted with EZVI. Laboratory tests conducted in 2005 suggest that both NZVI particles and EZVI containing NZVI can provide significant reductions in TCE mass when used to treat TCE DNAPL in small test reactors. However, EZVI was able to reduce TCE concentrations to lower levels than were obtained with NZVI alone, likely as a result of the combined impact of sequestration of the TCE into the oil phase and degradation of the TCE with the NZVI. © 2006 Wiley Periodicals, Inc.     

Purification and immunolocalization of a vitellin-like protein from the Pacific oyster Crassostrea gigas

A female-specific protein from the hemolymph, and a related ovarian protein were identified in the Pacific oyster Crassostrea gigas using immunological procedures. The latter protein was isolated from ovarian extract by a combination of precipitation in distilled water, ammonium sulfate fractionation, hydroxylapatite chromatography and gel filtration on a Sepharose 6B column, and was identified as a macromolecular glycolipoprotein of 500 kD; sodium dodecylsulfate polyacrylamide gel electrophoresis, under reducing conditions, revealed seven heterogeneous polypeptides. Using a specific antiserum against purified protein, we also examined the immunohistochemical distribution of the protein at light- and electron-microscopic levels. Light microscopy revealed its presence in the oocytes, and electron microscopy identified it in yolk granules and the vitelline coat of the oocytes. These results indicate that the purified protein is a vitellin-like protein. Since no organ other than the ovary reacted with the antiserum, it is probable that the protein is produced inside the ovary, probably autosynthetically by oocytes.     

Driver exposure to particulate matter in Bangkok

The aims of this study were to determine the particulate matter with aerodynamic diameters > or = 2.5 microm (PM2.5) and 2.5-10 microm (PM10-2.5) exposure levels of drivers and to analyze the proportion of elemental carbon (EC) and organic carbon (OC) in PM2.5 in Bangkok, Thailand. Four bus routes were selected. Measurements were conducted over 10 days in August (rainy season) 2008 and 8 days in January (dry season) 2009. The mean PM2.5 exposure level of the Tuk-tuk drivers was 86 microg/m3 in August and 198 microg/m3 in January. The mean for the non-air-conditioned bus drivers was 63 microg/m3 in August and 125 microg/m3 in January. The PM2.5 and PM10-2.5 exposure levels of the drivers in January were approximately twice as high as those in August. The proportion of total carbon (TC) in PM2.5 to the PM2.5 level in August (0.97 +/- 0.28 microg/m3) was higher than in January (0.65 +/- 0.13 microg/m3). The proportion of OC in the TC of the PM2.5 in August (0.51 +/- 0.08 microg/m3) was similar to that in January (0.65 +/- 0.07 microg/m3). The TC exposure by PM25 in January (81 +/- 30 microg/m3) remained higher than in August (56-21 microg/m3). The mean level of OC in the PM2.5 was 29 +/- 13 microg/m3 in August and 50 +/- 24 microg/m3 in January. In conclusion, the PM exposure level in Bangkok drivers was higher than that in the general environment, which was already high, and it varied with the seasons and vehicle type. This study also demonstrated that the major component of the PM was carbon, likely derived from vehicles.     

Difference in concentration trends of airborne particulate matter during rush hour on weekdays and Sundays in Tokyo,Japan

Suspended particulate matter (SPM) and fine particulate matter (less than or equal to 2.5 μm: PM_2.5) have generally been decreasing for the last decade in Tokyo, Japan. To elucidate the major cause of this decrease, the authors investigated the different trends of airborne particulates (both SPM and PM_2.5 concentrations) by evaluating comparisons based on the location of the monitoring stations (roadside vs. ambient), days of the week (weekdays vs. Sundays), and daily fluctuation patterns (2002 vs. 2010). Hourly mean SPM and PM_2.5 concentrations were obtained at four monitoring stations (two roadside stations, two ambient stations) in Tokyo, Japan. Annual mean concentrations of each day of the week and of each hour of the day from 2002 to 2010 were calculated. The results showed that (1) the daily differences in annual mean concentration decreased only at the two roadside monitoring stations; (2) the high hourly mean concentrations observed on weekdays during the daily rush hour at the two roadside monitoring stations observed in 2002 diminished in 2010; (3) the SPM concentration that decreased the most since 2002 was the PM_2.5 concentration; and (4) the fluctuation of hourly concentrations during weekdays at the two roadside monitoring stations decreased. A decreasing trend of airborne particulates during the daily rush hour in Tokyo, Japan, was observed at the roadside monitoring stations on weekdays since 2002. The decreasing PM_2.5 concentration resulted in this decreasing trend of airborne particulate concentrations during the daily rush hours on weekdays, which indicates fewer emissions were produced by diesel vehicles.

ImplicationsThe authors compared the trends of SPM and PM_2.5 in Tokyo by location (roadside vs. ambient), days of the week (weekdays vs. Sundays), and daily fluctuation patterns (2002 vs. 2010). The high hourly mean concentrations observed at the roadside location during rush hour on weekdays in 2002 diminished in 2010. The SPM concentration that decreased during rush hour the most was the PM_2.5 concentration. This significant decrease in the PM_2.5 concentration resulted in the general decreasing trend of SPM concentrations during the rush hours on weekdays, which indicates fewer emissions were produced from diesel vehicles.