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The Abundance, Species, Size Distribution and Influencing Factors of Airborne Microorganism in the Marine Boundary Layer and Polar Region

Author: LiMing
Tutor: XieZhouQing；SunLiGuang
School: University of Science and Technology of China
Course: Environmental Science
Keywords: Microorganism Marine boundary layer South Pole Arctic
CLC: Q93
Type: Master's thesis
Year: 2011
Downloads: 37
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Abstract

Microbial ecosystem which most closely associated with human part: on the one hand, the microorganisms involved in the production of fermentation engineering, medicine and engineering human life, on the other hand they are also closely related to human health. Micro-organisms in the atmosphere is affecting one of the factors in the atmospheric environment. They are both an important part of the atmospheric aerosol, also plays a special role in the process of material recycling and climate change, so the types of micro-organisms, the content in the atmosphere, in particular the large-scale distribution of more and more attention. In order to understand the temporal and spatial distribution of microorganisms in the atmosphere during the third Chinese National Arctic Research Expedition (2008.7-2008.9) and 26th Chinese Antarctic Scientific Expedition (2009.10-2010.4), based on the total bacteria in the atmosphere, sea source of bacteria, total fungi characteristics, in the sampling points along the route design. Site using the FA-1 six microbial air sampler, collecting the Arctic Ocean, the Sea of ??Okhotsk, Sea of ??Japan, China Yellow Sea, East China Sea, Philippine Sea, Coral Sea, the Southern Ocean, Antarctica inland places such as atmospheric microbial samples, and in situ microbial culture and statistical analysis. Specific results below: 1. Changes in the total content of the bacteria is large, some of the sample points is not detected. Up to 919 CFU/m3 (the number of bacterial colonies per cubic meter). The marine source of bacterial content from 4 CFU/m3 to 276 CFU/m3. General airborne microbes with latitude and reduce the southern hemisphere and the northern hemisphere more than less. This feature is more obvious. Terrigenous microorganisms 2 in the particle size distribution, maximum particle diameter greater than 8.2 μm, the minimum is less than 1.0μm. The large area change of the particle size of the micro-organisms and microbial aggregates is basically the same, but the small particle size of the micro-organisms in the high latitudes reduce speed slower than large particle size, so the rise in the proportion. Selected Arctic Ocean two sampling points collected samples, using 16S rDNA technology on which the microbial sample types were identified, mainly genus Bacillus genus Deinococcus. More than the content of microorganisms of the genus Deinococcus in the Arctic than Bacillus genus. Microbiological distribution has obvious regional characteristics (1) the overall Arctic sea microbial content is not high (average 102.47CFU/m3) and changes in the larger (coefficient of variation of 1.73); particle size aspects of small particle size ones, in the part of the sampling points , up to 50% the proportion of the microorganism of the diameter of less than 1.0μm. Terms of the types to four thick wall of Bacillus genus (circulaus, firmus, subtilis and alvei) and UV resistance characteristics of the Deinococcus genus two (grandis and murrayi), the largest number. By sea ice melting sea ice melting regional (floe zone) of microorganisms obvious impact. (2) Northwest Pacific Ocean microbial content with temperature changes significantly, showing the trend of the south than in the north, this area near the Asian mainland by land-based sources of microbial greater impact. Terrigenous microorganisms mainly by terrigenous air mass ratio can be as high as 60% or more. Particle size of microbiological aspects of coarse particles majority, the lower latitudes and more obvious. (3) Pacific Ocean and the Southern Ocean sea marine source microorganisms significantly higher (60% -80%), and the ratio is relatively stable (coefficient of variation of 0.87). Content on the Pacific Ocean (71 CFU/m3 -147 CFU/m3) slightly more than the Southern Ocean Ocean (56 CFU/m3 - 112 CFU/m3). (4) in the Antarctic inland microbial quantity obviously very rare, the the fluctuating range from 2 to 24 CFU/m3,. Slightly more close to the coast, deep into the Antarctic interior airborne microbes of various size are extremely rare, and show a random distribution of the particle size distribution. Atmospheric microbial content related to weather conditions and air mass movement meteorological conditions affect the performance of micro-organisms in terms of temperature, precipitation, and UV irradiation. Increasing latitude, the temperature of the sampling point is gradually reduced, the content of micro-organisms also showing a trend of gradual reduction. Precipitation of microorganisms in the atmosphere, mainly scouring action of rain or snow. UV irradiation has a more significant role in the high-latitude regions: on the one hand, UV irradiation tolerance species (Deinococcu, Bacillus, etc.) as well as the increase in proportion of dormant spores, on the other hand in the sea salt or snow The increase in the proportion of the particles of the smaller particle size of microorganisms. Air mass movement of airborne microbes. The air mass from the continent makes some sampling points airborne microbes mainly terrigenous, mainly Zeyi marine source microbial samples from marine air mass sampling points.

The Abundance, Species, Size Distribution and Influencing Factors of Airborne Microorganism in the Marine Boundary Layer and Polar Region

Abstract

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