兰州北山“三水”造林区柠条的生长适宜性

为了找出影响柠条生长的主导立地因子,确定适宜柠条生长的立地条件类型,在兰州北山"三水"造林区对不同立地条件下柠条的生长指标进行样地调查,运用相关分析和回归分析法研究立地因子和生长指标之间的关系,并采用模糊最优局势决策法评价柠条的生长适宜性。结果表明:海拔仅和株高呈极显著负相关关系;坡度与株高、基径和冠幅呈显著负相关关系;坡向与株高、丛枝数和冠幅呈显著负相关关系,坡度和坡向是影响柠条生长的主导立地因子。柠条最适生的立地类型为海拔1609～1658m、阴向、半阴向的缓坡;较适宜立地类型为海拔1659～1708 m、阴向、半阴向的缓坡和斜坡。

Growth suitability of Caragana korshinkii in Three Water Types afforested area in northern mountain of Lanzhou City

In order to find dominant site factors affecting growth of Caragana korshinkii and determine its suitable site type, growth indicators of C. korshinkii were investigated using sample plot method under different site conditions in Three Water Types afforested area in northern mountain of Lanzhou City, relationship between site factors and growth indicators were analyzed by correlation and regression analysis method and growth suitability Was evaluated using fuzzy optimization decision method. The results showed that the elevation only had highly significantly negative correlation with the tree height; the elevation was significantly negatively correlated to the tree height base diameter and crown; the slope aspect was markedly negatively correlated to the tree height, branch number, and crown. Slope degree and slope aspect were the leading factors affecting growth of C. korshinkii. The optimum site type for C. korshinkii were the conditions with the altitude of 1 609 - 1 658 m, shady and semi-shady mild slope and the more suitable type were the conditions with the altitude of 1 659 - 1 708 m, shady and semi-shady mild slope and slope.