高寒城市郊区外来园林树种适应性评价

Evaluation of Introduced Garden Tree Species in the Alpine Suburban Areas

为了确定外来园林树种在高寒城市郊区的适应性,以典型区域——青海西宁市火烧沟外来园林树种为对象,基于野外定株监测及室内统计分析,对其抗寒性、性状稳定性及生长发育能力等进行了研究,并综合评价了不同树种的适应能力。结果表明:(1)乔木树种紫叶稠李主干基部在晚冬期出现轻微冻裂,其他3种乔木在早春期发生了严重的抽条及轻度的冻害,4者叶色或叶形均明显改变,适应能力依次为:紫叶稠李>金叶复叶槭>金枝国槐>金叶榆。(2)小乔木类树种均发生了较严重的抽条,芽、叶、花出现了明显的冻斑,花朵变色或畸形率低于10%,适应性强弱依次为:西府海棠>独干红叶榆叶梅=绚丽海棠>红叶碧桃。(3)几种丁香属植物抵御冻害能力较强,仅部分物种一年生枝发生了轻微的抽条,但一些物种后期生长发育能力较差,例如黄丁香不发育花器官,综合适应能力大小为:紫罗兰丁香=波峰丁香=红叶丁香>辽东丁香>其他5者。(4)小灌木类树种胶东卫矛和小叶黄杨冬季地上部全部冻干,其他小灌木也发生了不同程度的冻害和抽条,球冠类适应能力为:榆叶梅=珍珠绣线菊>金叶榆>圆柏,绿篱类为:水蜡=紫叶矮樱>金叶榆。基于以上结果可以得出,高寒城郊区外来园林树种移栽初期抽条问题非常严重,因此建议采取一些行之有效的防抽条措施。

To determine the adaptability of introduced garden tree species in the alpine suburban areas,in Huoshaogou of Xinning,a typical alpine region,the abilities of the introduced garden trees to resist freezing injury and maintain characteristic stability were studied by using field plant monitoring and indoor statistical analysis.The results showed that:(1)a slight frost crack at the base of the trunk of Padus virginiana‘Canada Red’in late winter and serious shoot shriveling and mild freezing injury of other arbor species in early spring were observed,the color or shape of their leaves changed significantly,and their adaptability value declined in the order of P.virginiana‘Canada Red’>A.negundo‘Aurea’e>S.japonica‘Golden Stem’>U.pumila‘Jinye’;(2)the shoot shriveling(branches,trunks)and frozen spots(buds,leaves,flowers)in the introduced small-arbor species were relatively serious,however,the percentage of flower discoloration or deformity were very low(<10%),and the order of the comprehensive value of adaptability was:Malus micromalus>Amygdalus triloba+davidiana=M.‘Radiant’>A.persica f.atropurpurea;(3)most of introduced Syringa species possessed very strong ability to resist freezing injury,whilst only part of annual branches of the four species showed a slight strip;whereas,some species had poor growth and development ability,for example,the Syringa pekinensis var.jinyuan did not develop flower organ,moreover,the order of their comprehensive adaptability was:S.oblatacv Luo-Lan-Zi=S.oblata‘Buffon’=S.villosa>S.wolfii>the other five species;(4)the branches or leaves of Euonymus kiautschovicu and Buxus sinica var.Parvifolia were freeze-dried in winter,and the other small shrubs also suffered different degrees of freezing injury and shoot shriveling,the adaptability of shrub species with spherical crown pattern was Prunus triloba var.plena=Spiraea thunbergii>U.pumila‘Jinye’>Sabina chinensisr,and the adaptability of the species used for hedgerow was Ligustrum obtusifolium=P.×cistenena‘Pissardii’>U.pumila‘Jinye’.Based on the above results,it is concluded that shoot-shriveling of the introduced garden tree species in Alpine suburban areas is very serious,so some effective measures of preventing shoot shriveling should be taken at the early stage after transplanting.