云南热区坡柳对立地因子的生长响应

Growth Response of Dodonaea viscosa L. to Different Site Factors in the Hot Regions of Yunnan Province

为了探讨不同立地因子对热区坡柳(Dodonaea viscosa L.)生长特征的影响,确定影响坡柳生长主导因子,在对坡柳在云南热区的资源分布进行初步踏查的基础上,选择14个地区开展了坡柳株高、地径、冠幅及生物量的调查,并进行了统计分析。结果表明:部分地区坡柳生长差异显著,其中大姚地区生物量最高,达到14.14 t·hm-2;低海拔区坡柳平均地径、平均株高及生物量均大于高海拔地区,分别为18.28 mm、179.16 cm和8.94 t·hm-2,但海拔高度对坡柳生物量及生长特征的影响未达到显著水平;坡柳总生物量、平均地径和平均株高均随坡位变化自下而上逐渐减少,下坡位生物量最大,达到10.01 t·hm-2,且上坡位生物量、平均地径及平均株高显著低于中坡位、下坡位(P<0.05);坡向对坡柳生长影响不明显,但是阴坡地段坡柳的生长指标平均地径、平均株高和总生物量都要优于阳坡地段。因此,可以认为影响坡柳生长的主导立地因子是坡位,坡柳最适宜的立地条件为低海拔,下坡位和阴坡。

We investigated the influence of different site factors on the growth characteristic of Dodonaea viscosa L.in the hot re-gions, and the factors on the growth of the D.viscosa.We selected 14 regions as the sampling plots based on the extensive field survey on the resource of main distribution area of D.viscosa in Yunnan Province to measure the plant height , basal diameter, crown diameter and biomass of D.viscosa in each plot.The growth characteristics of D.viscosa were significant in some sampling plots.Biomass in Daoyao County was the highest among all sampling plots with the amount of 14.14 t· hm-2 .The mean diameter , average height and biomass of low altitudes were 18.28 mm, 179.16 cm and 8.94 t· hm-2 , re-spectively .They were higher than those of high altitudes , but not reached statistical significant level .The mean diameter , height and increased with the decrease of slope position .The highest biomass were in downhill with amount of 10.01 t· hm-2 , the mean diameter , height and biomass at upper slope were significant lower than those at downhill and middle slope （P〈0.05）.The effect of slope aspect on the growth of D.viscosa was insignificant.However, the growth indexes including mean diameter , height and biomass on the shady slope were slightly higher than those on the sunny slope .The determinate site factor was slope position , and the best site factor for D.viscosa was the combination of lower altitude , downhill and shady slope .