对广西北热带山口林场２ 种林龄窿缘桉防护林内及空旷地的主要气象要素进行定位对比观测。结果表明： １５ 年生和４５ 年生窿缘桉林内的平均太阳辐射日总量分别为２４６ ×１０３ ｋ Ｊ·ｍ － ２ 和２０２ ×１０３ ｋ Ｊ·ｍ － ２ ， 分别比空旷地（５４３ ×１０３ ｋ Ｊ·ｍ － ２）减少５４７ ％ 和６２８ ％ ； 平均气温分别低０２ ℃和０７ ℃； ０ ～２０ ｃｍ 土层的平均温度分别低１３ ℃和１８ ℃； 平均空气相对湿度高１ ％ 和３ ％ ； ４５ 年生林内的平均风速降低８２４ ％ 。表１ 参９ The main meteorological elements in two types of forest eucalyptus and their open areas in north tropical mountain pass of Guangxi were compared. The results showed that the average daily solar radiation days in eucalyptus forests of 15 years and 45 years were 2.46 × 103 kJ · m -2 and 202 × 103 kJ · m -2, respectively Which is 547% and 628% less than the open area (543 × 103 kJ · m -2), respectively. The average temperature is lower than or equal to 02 ℃ and 07 ℃, respectively. The average temperature of 0 ~ 20 cm soil layer Respectively, 13 ℃ and 18 ℃ lower; average relative humidity of 1% and 3% respectively; average wind speed of 45 years decreased by 824%. Table 1 reference 9