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吴旗县年平均气温7.8℃,最高气温37.1℃,最低气温-25.1℃,≥10℃的活动积温28.8℃,无霜期100～150天,年平均降水量483.4厘米,干燥度1.53。据调查,全县目前有刺槐人工林6400多亩,蓄积9700多米~3。为摸索刺槐在吴旗县的生长规律,我们在不同立地条件下选择了36块标准地,结合伐取解析本,对刺槐的生长情况进行了调查。结果得出:(1)11龄刺槐的平均高为10.0米,平均胸径11.26厘米,在自然条件较好的沟底部位,年均高生长量可达1.30米,年均胸径生长量可达1.51厘米。(2)刺槐在10龄前高生长最快,10龄后便开始大幅度下降。胸径生长最快出现在5年后,持续时间较长,15年后开始大幅度下降。(3)地貌部位、坡度、坡向等因子对刺槐生长有显著影响,海拔因子影响不显著。(4)水分因子是影响林木生长的主导因子。
Wuqi County, the annual average temperature of 7.8 ℃, the highest temperature of 37.1 ℃, the lowest temperature of -25.1 ℃, ≥ 10.0 ℃ accumulated temperature 28.8 ℃, frost-free period of 100 to 150 days, the average annual rainfall of 483.4 cm, dryness of 1.53. According to the survey, there are currently 6400 mu of acacia plantation in the county, accumulating over 9,700 meters ~ 3. In order to explore the law of growth of Robinia pseudoacacia in Wuqi County, we selected 36 standard plots under different site conditions, and investigated the growth of Robinia pseudoacacia in combination with the analysis of fecundity. The results showed that: (1) The 11-day-old locusts had an average height of 10.0 m and an average diameter of 11.26 cm. The average annual height growth of up to 1.30 m was achieved at the bottom of ditches with good natural conditions. The average annual DBH growth was 1.51 cm. (2) Robinia pseudoacacia grew fastest before the tenth instar and began to decline significantly after the tenth instar. The fastest DBH growth occurred after 5 years and lasted for a long time and dropped sharply after 15 years. (3) The topography, slope, aspect and other factors have significant effects on the growth of Robinia pseudoacacia, and the influence of altitude factors is not significant. (4) Water factor is the dominant factor affecting the growth of trees.