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Bacterial Characteristics of Dust Particle Saltation in Gobi Dust Sites, Mongolia

Katsuro Hagiwara, Tamaki Matsumoto, Purevsuren Tsedendamba, Kenji Baba, Buho Hoshino
2021 Atmosphere  
The Gobi Desert is a major source of Asian dust events, and the resulting health hazards have increased significantly in recent years. We reported that a variety of live bacteria were distributed in the Gobi Desert in relation to land use. Bacterial distribution was confirmed in the environment and on the land used by animals; however, bacterial saltation due to dust events has not been investigated in detail. In this study, to understand the distribution of surface bacteria in the atmosphere
more » ... dust saltation, live bacteria in four dust-generating areas in the Gobi area were monitored using an artificial dust generating device. The live bacteria were detected by experimental saltation at a wind speed of 6.5–8 m/s in all areas. A certain number of live bacteria are constantly saltated by dust events, and these bacteria depend on land use. Moreover, the bacterial saltation strain depended on land use and diversity, indicating that live bacteria are lifted into the environment by dust events. These findings indicate that dust events saltate environmental bacteria on the ground, suggest the risk of animal-derived bacterial saltation affected by land use, and present cross-border public health challenges to be considered in the future.
doi:10.3390/atmos12111456 fatcat:ncugamolg5d4bca7drxyib27cu

Distribution of Viable Bacteria in the Dust-Generating Natural Source Area of the Gobi Region, Mongolia

Katsuro Hagiwara, Tamaki Matsumoto, Purevsuren Tsedendamba, Kenji Baba, Buho Hoshino
2020 Atmosphere  
The Gobi Desert is a major source of dust events, whose frequency of occurrence and damage caused have recently significantly increased. In the present study, we investigated the types of live bacteria present in the surface soil of the Gobi Desert in Mongolia, and determined their genetic identification as well as their geographical distribution. During the survey, four different topographies (dry lake bed, wadi, well, and desert steppe) were selected, and land characteristics were monitored
more » ... r moisture and temperature. The surface soil was aerobically cultured to isolate bacterial colonies, and their 16s rDNA regions were sequenced. The sequence data were identified through NCBI-BLAST analysis and generated phylogenetic trees. The results revealed two phyla and seven families of isolates from the sample points. Each isolate was characterized by their corresponding sample site. The characteristics of land use and soil surface bacteria were compared. Most of the bacteria originated from the soil, however, animal-derived bacteria were also confirmed in areas used by animals. Our findings confirmed the existence of live bacteria in the dust-generating area, suggesting that their presence could affect animal and human health. Therefore, it is necessary to further investigate dust microbes based on the One Health concept.
doi:10.3390/atmos11090893 fatcat:dbchece5bnhkvohwe6k3jlzp5a

Determining the Frequency of Dry Lake Bed Formation in Semi-Arid Mongolia From Satellite Data

Yuta Demura, Buho Hoshino, Kenji Baba, Christopher McCarthy, Yuki Sofue, Kenji Kai, Tsedendamba Purevsuren, Katsuro Hagiwara, Jun Noda
2017 Land  
In the Mongolian Plateau, the desert steppe, mountains, and dry lake bed surfaces may affect the process of dust storm emissions. Among these three surface types, dry lake beds are considered to contribute a substantial amount of global dust emissions and to be responsible for "hot spots" of dust outbreaks. The land cover types in the study area were broadly divided into three types, namely desert steppe, mountains, and dry lake beds, by a classification based on Normalized Difference Water
more » ... x (NDWI) calculated from MODIS Terra satellite images, and Digital Elevation Model (DEM). This dry lake beds extracting method using remote sensing offers a new technique for identifying dust hot spots and potential untapped groundwater in the dry lands of the Gobi region. In the study area, frequencies of dry lake bed formation were calculated during the period of 2001 to 2014. The potential dry lake area corresponded well with the length of the river network based on hydrogeological characterization (R 2 = 0.59, p < 0.001). We suggest that the threshold between dry lake bed areas and the formation of ephemeral lakes in semi-arid regions is eight days of total precipitation.
doi:10.3390/land6040088 fatcat:wmewhjbfbbd3djog36234b5one

Northeast Asian Dust Transport: A Case Study of a Dust Storm Event from 28 March to 2 April 2012

Purevsuren Tsedendamba, Jugder Dulam, Kenji Baba, Katsuro Hagiwara, Jun Noda, Kei Kawai, Ganzorig Sumiya, Christopher McCarthy, Kenji Kai, Buho Hoshino
2019 Atmosphere  
The distribution and transport of windblown dust that occurred in Northeast Asia from 28 March to 2 April 2012 was investigated. Data of particulate matter less than 10 micrometers (PM10) near the surface and light detection and ranging (LiDAR) measurements from the ground up to 18 km were used in the study. A severe dust event originated over southern Mongolia and northern China on 28 March 2012, and the widespread dust moved from the source area southeastward toward Japan over several days.
more » ... ndblown dust reached Japan after two days from the originating area. LiDAR measurements of the vertical distribution of the dust were one to two km thick in the lower layer of the atmosphere, and increased with the increasing distance from the source area.
doi:10.3390/atmos10020069 fatcat:xazmwc3h7rbo7cmmor6op7chsi

Imaging of micro-organisms on topsoil particles collected from different landscape in the Gobi Desert

Morine Kuribayashi, Keiichi Kawano, Yuta Demura, Kenji Baba, Yuki Sofue, Purevsuren Tsedendamba, Tamaki Matsumoto, Katsuro Hagiwara, Olaf Karthaus, Kenji Kai, Buho Hoshino, D. Altausen (+2 others)
2019 E3S Web of Conferences  
This study shows the results of field experiments of soil particles saltation and laboratory experiments of imaging of the surface structure of dust particles. In the Gobi area, dust occurs when the wind speed at ground level exceeds 7 m/s. It has been reported that bacteria are attached to dust, but the details of its attachment are unknown. It is also expected that these bacteria will fly at the time of occurrence of dust, and fundamental research is important to clarify the relationship between dust components and bacteria.
doi:10.1051/e3sconf/20199901011 fatcat:vefgosifzzgsxfpzic4slvrnna