Kira与Holdridge热量指标对常绿树种耐低温能力的评价

广泛收集了南京地区分布或栽培的14种常绿阔叶树种的分布资料,利用目前被国际公认的研究植被—气候相互关系的2种指标,K ira热量指标与Holdridge热量指标,以及年平均气温,计算了14种树种的寒冷指数以及生物温度的最适范围、全范围与均值,分析了这些树种的耐低温能力.结果表明2种热量指标基本能很好地反映树种本身耐低温能力高低,如大叶冬青,其自然分布于亚热带北纬32,°运用上述2种热量指标都表示大叶冬青耐低温能力强,这与大叶冬青本身引种到南京地区的越冬表现相一致.因此该研究结果对常绿阔叶树种耐低温评价以及在高纬度地区园林中的合理运用有一定的指导意义.

Application of Kira and Holdridge''''s temperature indexes to low temperature tolerance of evergreen trees

Based on the records of geographical distribution of 14 evergreen broad-leaved trees collected extensively,which mainly distributed or cultivated in Nanjing,two international accepted indexes of vegetation-climate interaction including Kira′s temperature index and Holdridge′s temperature index were used.Coldness index(CI) and biotemperature(BT) of 14 trees were used to(analyse) the ability of them to withstand the rigors of cold temperature.The results indicated two temperature indexes were correspondent nearly to their low temperature tolerance,the best example was that the stronger hardness of Ilex latifolia calculated in two temperature indexes was unanimous to adaptability to winter in Nanjing,and it naturally distributed to 32° north latitude.Altogether the results were conducive to predicting the low temperature tolerance of evergreen tree species and the reasonable cultivation of them in landscape forests of higher latitude regions.