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Vegetative barriers as porous medium are considered to be effective to purify air,including collecting particulates matter(PM).A study was conducted to investigate the effect of porous structure and micro-scale surface characteristics of vegetation barriers on the mitigation of particulate matter in the wind tunnel.Since lots of particulate matters may emit from concentrated animal feeding operations(CAFOs)and affect the health of residents and air quality in rural communities,leading to public concern,the emission sources of PM from CAFOs were considered in this study.Dust and soil were collected from the pen and ventilation area of a laying-hen house in Jilin Province of China and grinded into two levels of powder with 5%and 10%of fine particles,which were used as the PM source for the wind tunnel tests.The concentrations of PM(PM2.5,PM10,and total suspended particulates or TSP)at upwind and downwind of the barriers were measured in the wind tunnel at three wind speed of 0.8m/s,1.6m/s and 2.7m/s.The velocity of airflow through vegetation barriers were simultaneously measured at five points besides the two PM concentration-monitoring points using hot-wire anemometers.At present,experiments were performed under three levels of surface area density with 198 leaves,132 leaves and 66 leaves in the volume of vegetative barriers of mature syzygium aromaticum.In addition,to decide critical micro-scale structures that affected particle collection efficiency,leaves samples with more accumulated dust were observed via scanning electron microscope(SEM).There will be another two species of plants tested for the comparison in the coming time.This study will provide basic information for future bionic research on porous structure and micro-scale surface characteristics of vegetation barriers.