CAJ | 학술논문

为剖析长春市城区近地表灰尘粒度特征，分别沿南北和东西轴线采集了34件城市近地表灰尘样品，采用激光粒度仪对样品进行了粒度测试分析。结果表明：长春市近地表灰尘颗粒物平均中值粒径和算术平均粒径分别为21．58μm和24．24μm ，分选极差；以粗粉粒（10．00～80．00μm ）为主，平均约占71．28％，黏粒组（＜5．00μm ）和细粉粒组（5．00～10．00μm ）分别约占14．75％和13．05％。频率曲线呈正偏双峰型分布，峰态中等偏窄，与现代尘暴和城市街道灰尘分布特征相一致，反映出其起源的多元性和相对稳定性，表明近地表灰尘沉积仍是风积作用的继续。近地表灰尘颗粒物粒径均小于100．00μm ，极易在外动力条件下再次扬起并悬浮搬运，PM 10和PM 2．5所占比例分别为27．76％和7．32％，其生态环境效应不应被忽视。粒径分布无显著空间变化，但城市中心区域粒径变化范围小，这可能说明城市边缘区域较中心区域近地表灰尘的起源更具多源性和复杂性。
위부석장춘시성구근지표회진립도특정，분별연남북화동서축선채집료34건성시근지표회진양품，채용격광립도의대양품진행료립도측시분석。결과표명：장춘시근지표회진과립물평균중치립경화산술평균립경분별위21．58μm화24．24μm ，분선겁차；이조분립（10．00～80．00μm ）위주，평균약점71．28％，점립조（＜5．00μm ）화세분립조（5．00～10．00μm ）분별약점14．75％화13．05％。빈솔곡선정정편쌍봉형분포，봉태중등편착，여현대진폭화성시가도회진분포특정상일치，반영출기기원적다원성화상대은정성，표명근지표회진침적잉시풍적작용적계속。근지표회진과립물립경균소우100．00μm ，겁역재외동력조건하재차양기병현부반운，PM 10화PM 2．5소점비례분별위27．76％화7．32％，기생태배경효응불응피홀시。립경분포무현저공간변화，단성시중심구역립경변화범위소，저가능설명성시변연구역교중심구역근지표회진적기원경구다원성화복잡성。
A series of investigations were performed to provide particle size signatures of urban dust near the ground in Changchun ,China .A total of 34 samples of dust were collected along the north-south and the east-west axis using a systematic sampling strategy (about 1 .5 m above the ground surface) .The laser particle size instrument was employed to analyze the particle size .According to the analytical results ,the mean median grain size and the arithmetic mean diameter of the near-surface urban dusts in Changchun was 21 .58 μm and 24 .24 μm ,respectively .The coarse silt (10 .00 80 .00 μm) content in the urban dusts was higher relatively ,which was 71 .28% on average ,while the clay particle (<5 .00 μm) and fine silt (5 .00 10 .00 μm) was 14 .75% and 13 .05% ,respectively .The distribution of grain size was characterized by skewed positively ,bimodal and middling to narrow kurtosis ,which was similar to the gain size distribution of modern dust storms and street dust and indicated that urban dust near the ground is a mixture of coarse grains derived from local area and fine grains transported over long distances ,and was derived from aeolian processes .The gain size in urban dust near the ground was almost completely below 100 .00 μm ,which indicated that these particles were pick up and transported by suspension under proper aerodynamic conditions .Meanwhile ,the average content of PM10 and PM2 .5 in urban dust near the ground was 27 .76% and 7 .32% ,respectively ,which were much higher ,showing the high potential hazards . There were no significant spatial variations of gain size distribution , however ,the variation range of grain size in central urban area was small relatively ,which indicated that the origination of urban dust near the ground was multiple and complicated in suburban compared with that of the central urban area .