14种竹子在西藏拉萨引种的适应性

Adaptation of 14 Woody Bamboo Species in Lhasa,Tibet,China

以位于拉萨市郊的西藏自治区林木科学研究院苗圃为试验地,以园林绿化竹种为研究对象,自2018年3月起,从西藏引种高山竹类4种、从浙江引种温带竹类7种、从云南引种热带竹类3种;竹苗定植后,于2018年8月份和2019年8月份,测量引种的14个竹种在西藏拉萨栽植近2 a的苗木成活、发笋数量、新笋(幼竹)干径和干高,分析14种竹子在西藏拉萨引种的适应性。结果表明:高山竹类中的西藏本地箭竹属(Fargesia)、筱竹属(Thamnocalamus)竹种具有最高的成活率(62.8%~87.5%),发笋率为4.1%~12.5%;温带竹类中的罗汉竹(Phyllostachys aurea)、黄竿京竹(Ph.aureosulcata f.aureocaulis)、赤竹属菲白竹(Sasa fortunei)等具有较高的成活率(39.0%~66.4%),发笋率为2.0%~2.9%,性状基本正常;其余的温带竹种成活率急剧下降,发笋率低;3种热带竹种栽种2 a后全部死亡。竹苗中,分株数量、竹种原分布区海拔,与竹子分篼苗的成活率、发笋率之间存在显著相关性(r=0.740~0.835,P<0.01);累年日平均气温、累年平均日最低气温,与成活率、发笋率之间存在负相关关系(r=-0.997~-0.909)。不同类型竹种,在当地的适应性差异显著。在拉萨进行园林绿化竹子引种时,应优先考虑当地的牛色玛(Thamnocalamus unispiculatus)等抗寒性较强的高山竹种,避免因较长时间低温影响竹种的成活和生长。

In order to expand ornamental bamboo resources for landscaping in Lhasa,Tibet,China,seedlings of 14 candidate bamboos,including 4 alpine bamboos from Tibet,7 temperate bamboos from Zhejiang and 3 tropical bamboos from Yunnan,were introduced and planted at the nursery of the Institute of Forestry Sciences of Tibet Autonomous Region since March 2018.In August 2018 and August 2019,the survival rate of seedlings,number of shoots,culm diameter and height of young culm of the introduced bamboos were measured to investigate and analyze their adaptability in Lhasa.The four native alpine species from Fargesia and Thamnocalamus possessed highest survival rates(62.8%-87.5%)and shooting rate(4.1%-12.5%).Among 7 temperate bamboos,Phyllostachys aurea,P.aureosulcata f.aureocaulis and Sasa fortunei had reasonably high survival rate(39.0%-66.4%)and shooting rate(2.0%-2.9%)with totally normal growth and development,while the survival rate of remaining temperate bamboos decreased sharply,and the shooting rate was low.On the other hand,all three tropical bamboo species died after two-year planting.Of bamboo seedlings,the number of ramets and the altitude of original distribution areas were significantly correlated with the survival rate and shooting rate(r=0.740-0.835,P<0.01),while the annual average daily temperature and the annual average daily minimum temperature were negatively correlated with the survival rate and shooting rate(r=-0.997--0.909).The above results indicated that adaptability of different types of bamboo species in Lhasa was significantly different.As a whole,when introducing ornamental bamboos for landscaping in Lhasa,priority should be given to native alpine bamboo species with strong cold resistance,such as T.unispiculatus,to avoid low survival and weak growth of bamboo species affected by long-term low temperature.