关键词: 北京地区, 风沙活动, 监测, 风沙天气, 沙尘暴, 扬沙, 浮尘, Q-V图

Abstract: Following two-year survey from 1985 to 1986,the Beijiang Wind-sand control experiment station conducted monitoring of wing-sand activities in sandy soil areas of southeastern Berjing.The monitoring resuits show that:1.The number of days with wind-sand is continuously decreasing,e.g,the annual mean number of days with wind-sand decreased from 19.8 in 1981-1985 to 12.4 in 1986-1990.2.The sand of wind-sand activities mainly come from local origin,therefore,we must put priority on local sand control sand control in the comming years.In 1951-1985 the number of bloqing sand days occupied 71.6%,while in 1986-1990 this value reached up to 77.4%.3.The ratio between the number of days with wind-sand and the number of days with gale reduced from 1.40 in the past 35 years to 0.82 in recent 5 years.4.The results observated in typical areas show that under the same wind velocity the blowing sand amount greatly reduced due to increasing vegetation cover and soil crust fromed on cultivated sruface.5.Obserbation results in sandy loam fields showed that the total dustfall deposition rate from April of 1990 to March of 1991 was 267.9 T/km².yr,monthy averaged 22.31 T/km²,i.e.slightly higher than the mean value in urban area of Beijing.