Search Results (7)

Estimating the source contribution to polycyclic aromatic hydrocarbons (PAHs) and nitropolycyclic aromatic hydrocarbons (NPAHs) in the atmosphere is necessary for developing effective disease control and pollution control measures. The NPAH-PAH combination method (NP method) was used to elucidate the contributions of vehicles and coal/biomass combustion to seasonal and long-term urban atmospheric particulate matter (PM)-bound Pyr and 1-NP concentrations in Kanazawa, Kitakyushu, Shenyang and Shanghai in the Western Pacific region from 1997 to 2021. Among the four cities, Kanazawa demonstrated the lowest Pyr concentration. The contribution of vehicles to Pyr before and after 2010 was 35% and 5%, respectively. The 1-NP concentration was reduced by a factor of more than 1/10. These changes can be attributed to the emission control from vehicles. Kitakyushu revealed the second-lowest Pyr and the lowest 1-NP concentrations. Coal combustion was found to be the main contributor to Pyr, while its contribution to 1-NP increased from 9% to 19%. The large contribution of coal combustion is attributed to iron manufacturers. Shenyang demonstrated the highest atmospheric Pyr concentration with its largest seasonal change. Vehicles are the largest contributors to 1-NP. However, coal combustion, including winter coal heating, contributed 97% or more to Pyr and more than 14% to 1-NP. Shanghai revealed the second-highest Pyr and 1-NP concentrations, but the former was substantially lower than that in Shenyang. Coal combustion was the major contributor, but the contribution of vehicles to Pyr was larger before 2010, which was similar to Kanazawa. Full article

To reduce atmospheric pollutants, the sources need to be identified. To this end, combustion-derived particulates (P_c) in atmospheric suspended particulate matter (TSP) in ten Western Pacific cities from 1997 to 2018 were analyzed using the NP method, which we have recently developed. The method separates P_c into particulates originating from high-temperature (P_h) and low-temperature (P_l) combustion sources. Using this method, ten cities in the Asia-Pacific region were separated into three classes. Class 1: commercial cities whose major contributor to P_c was from vehicles, and which showed lower [P_c] values with larger [P_h]/[P_c] ratios. Sapporo, Kanazawa, Tokyo, Sagamihara (Japan), Shanghai (China), and Busan (Korea) were contained in this class. Class 2: cities whose main source of P_c was from coal heating, and which showed much higher winter [P_c] with larger [P_l]/[P_c] ratios. Beijing, Shenyang (China), and Vladivostok (Russia) were contained in this class. Class 3: steel manufacturing city which showed lower [P_c] with larger [P_l]/[P_c] ratio. The low [P_c] appeared to be due to elimination of P_l from coke oven plants. Only Kitakyushu was contained in this class. This study has elucidated the contribution of sources to urban atmospheric TSP in the Western Pacific that was previously unknown. Overall [P_c] was decreasing in this region, mainly due to the decreasing contribution of vehicles to P_c, but not due to a decrease in coal combustion. Full article

Outdoor thermal comfort is an important indicator to create a quality and livable environment. This study examines a relationship between micro-meteorological and personal variables of outdoor thermal comfort conditions in an urban park. The data collection of outdoor thermal comfort is carried out using two methods in combination: micro-meteorological measurement and questionnaire survey. This finding shows that most of the respondents were comfortable with the thermal, wind, and humidity condition. The acceptability and satisfaction level of thermal comfort were positive. The most significant micro-meteorological variable for the physiologically equivalent temperature (PET) value is mean radiant temperature (Tmrt). As the Tmrt value is influenced by how much shading is produced from the presence of vegetation or buildings around the measurement location, this finding shows that the shadow was very important to the thermal comfort conditions in the Green Park Kitakyushu. The most influential micro-meteorological variable for the three different personal variables (TSV, WFSV, and HSV) is air temperature. The strongest relationship among the four variables is between TSV and PET. The findings will be the basis for the city authorities in preparing regional development plans, especially those related to the planning of city parks or tourist attractions. Full article

The generation of map units is a fundamental step for an appropriate assessment of landslide susceptibility. Recent studies have indicated that the terrain relief-based slope units perform better in homogeneity compared with the grid units. However, it is difficult at present to generate high-precision and high-matching slope units by traditional methods. The problem commonly concentrates in the plain areas without obvious terrain reliefs and the junction of sudden changes in terrain. In this paper, we propose a novel object-oriented segmentation method for generating homogeneous slope units. Herein, the multi-resolution segmentation algorithm in the image processing field is introduced, enabling the integration of terrain boundary conditions and image segmentation conditions in slope units. In order to illustrate the performances of the proposed method, Kitakyushu region in Japan is selected as a case study. The results show that the proposed method generates satisfactory slope units that satisfactorily reproduce the actual terrain relief, with the best within-unit and between-unit homogeneities compared with the previous methods, in particular at the plain areas. We also verify the effectiveness of the presented method through the sensitivity analysis using different resolutions of digital elevation models (DEMs) data of the region. It is reported that the presented approach is notably advanced in the requirements of the quality of DEM data, as the presented approach is less sensitive to DEM spatial resolution compared with other available methods. Full article

Industrial heritage tourism is aimed at promoting sustainable development in the regional social economy. Japan published Heritage Constellations of Industrial Modernization in 2007 and 2008, and treated them as an important resource to promote the activation of the local economy. Evolutionary economic geography offers a useful framework for studying the evolution of industries and has already been applied to study the different types of tourism destinations, what is often unclear, however, is under what conditions declining industrial cities can be transformed into an industrial heritage tourism destination and by whom. Thus, this article tries to employ the EEG approach to understand the development of industrial heritage tourism in Japan, using Kitakyushu City as a case. The case of Kitakyushu City illustrates the importance of initial conditions and stakeholder collaboration in promote the development of industrial heritage tourism. The results of this study also showed that participation of community residents and the application of new technologies, strong support from national and local governments are critical to the new path creation. Full article

We sequenced the entire genomes of ten biphenyl/PCB degrading bacterial strains (KF strains) isolated from biphenyl-contaminated soil in Kitakyushu, Japan. All the strains were Gram-negative bacteria belonging to β- and γ-proteobacteria. Out of the ten strains, nine strains carried a biphenyl catabolic bph gene cluster as integrative conjugative elements (ICEs), and they were classified into four groups based on the structural features of the bph genes. Group I (five strains) possessed bph genes that were very similar to the ones in Pseudomonas furukawaii KF707 (formerly Pseudomonas pseudoalcaligenes KF707), which is one of the best characterized biphenyl-utilizing strains. This group of strains carried salicylate catabolic sal genes that were approximately 6-kb downstream of the bph genes. Group II (two strains) possessed bph and sal genes similar to the ones in KF707, but these strains lacked the bphX region between bphC and bphD, which is involved in the downstream catabolism of biphenyl. These bph-sal clusters in groups I and II were located on an integrative conjugative element that was larger than 110 kb, and they were named ICE_bph-sal. Our previous study demonstrated that the ICE_bph-sal of Pseudomonas putida KF715 in group II existed both in an integrated form in the chromosome (referred to as ICE_bph-salKF715 (integrated)) and in a extrachromosomal circular form (referred to as ICE_bph-sal (circular)) (previously called pKF715A, 483 kb) in the stationary culture. The ICE_bph-sal was transferred from KF715 into P. putida AC30 and P. putida KT2440 with high frequency, and it was maintained stably as an extrachromosomal circular form. The ICE_bph-salKF715 (circular) in these transconjugants was further transferred to P. putida F39/D and then integrated into the chromosome in one or two copies. Meanwhile, group III (one strain) possessed bph genes, but not sal genes. The nucleotide sequences of the bph genes in this group were less conserved compared to the genes of the strains belonging to groups I and II. Currently, there is no evidence to indicate that the bph genes in group III are carried by a mobile element. Group IV (two strains) carried bph genes as ICEs (59–61 kb) that were similar to the genes found in Tn4371 from Cupriavidus oxalacticus A5 and ICE_KKS1024677 from the Acidovorax sp. strain KKS102. Our study found that bph gene islands have integrative functions, are transferred among soil bacteria, and are diversified through modification. Full article

In coastal cities, the effect of the sea breeze in mitigating the urban heat island (UHI) phenomenon has attracted attention. This study targeted the Fukuoka–Kitakyushu metropolitan area, the fourth largest metropolitan area in Japan which is also coastal. Doppler Light Detection And Ranging (LiDAR) observations were conducted in the summer of 2015 to clarify the transition of the wind field over the targeted area. To investigate the effects on the UHI of land-use change related to urbanization, the National Land Numerical Information (NLNI) land-use datasets for Japan in 1976 (NLNI-76) and 2009 (NLNI-09) were used in the Weather Research and Forecasting (WRF) model. The results of the simulation showed that most of the northern part of the Kyushu region became warmer, with an average increase of +0.236 °C for the whole simulation period. Comparing the two simulations and the Doppler LiDAR observations, the simulation results with the NLNI-09 dataset (for the year closest to the study period in 2015) showed closer conformity with the observations. The results of the simulation using NLNI-76 showed faster sea breeze penetration and higher wind velocity than the observations. These results suggest that the land-use change related to urbanization weakened the sea breeze penetration in this area. Full article