论文部分内容阅读
金沙江边宁南县南华弹乡段,属干热河谷地带,年平均气温22℃,绝对高温42.7℃,年降雨量742mm,蒸发量1940mm,相当于降雨量的近3倍.土壤趋于沙化.1965年南宁县林业局,在该乡营造木麻黄防护林,长12km,宽30m.目前树木长势良好,据实测22年生树高21m,胸径1.38m,冠幅7.3m;12年生树高20m,胸径0.85m,冠幅5.8m; 11年生树高15.1m,胸径
The Nanhua Danxiang section of Ningnan County in the Jinsha River is a dry and hot valley with an annual average temperature of 22 ℃ and an absolute high temperature of 42.7 ℃ with annual rainfall of 742mm and evaporation of 1940mm, equivalent to nearly 3 times of rainfall. 1965 Nanning County Forestry Bureau, in the township to build Casuarina Shelterbills, 12km long and 30m wide. At present the trees grow well, according to the actual measured 22-year-old tree height 21m, diameter 1.38m, crown 7.3m; 12-year-old tree height 20m, DBH 0.85m, crown width 5.8m; 11-year-old tree height 15.1m, DBH