青海省三江源区高海拔城镇园林树种的组成与生长调查

Composition of Tree Species and Structure of High-altitude Towns in Sanjiangyuan Region

本文以三江源区海拔高于3500 m的城镇绿化树种为研究对象,介绍了9个城镇绿化树种的组成,生长结构特征及不同绿地类型中树种应用状况。结果表明:(1)三江源高海拔城镇绿化树种有30种,11科,29属,其中针叶树种5种,占比38.0%。阔叶树种25种,占比62.0%;乡土树种9种,占比52.4%,外来树种21种,占比47.6%。(2)绿化树种的平均树高为1.6 m,平均冠幅为0.9 m。树高和冠幅<2 m的树木占的比例较多,分别为54.4%和91.2%,2 m以上的树木所占的比例少。(3)在庭院、广场、行道树和滨河4种绿地类型中青海云杉、紫丁香、榆叶梅和珍珠梅应用的最多。总体看,三江源高海拔城镇绿化树种丰富度偏低,景观配植简单。

The species composition,growth structure and application in different green space types of nine urban greening tree species of high-altitude towns in Sanjiangyuan region were described in this paper.The results showed that i)there are 30 species of plant belonging to 29 genera in 11 families;5 species of tree belonging to coniferous trees with proportion of 38.0%whereas 21 species of tree belonging to broadleaf trees,accounting for 62.0%.9 species of tree are native trees,accounting for 52.4%;21 species of tree are alien trees,accounting for 47.6%;ii)the average height is 1.6m,and the average crown width 0.9m.There are majority of trees with height or crown width less than 2.0 m,that is,54.4%and 91.2%respectively.Trees over 2.0 m in height are less;iii)there are more trees planted in 4 kinds of green spaces-courtyard,square,streets and riverside,tree species like Picea crassifolia Kom.,Syringa oblata Lindl.,Amygdalus triloba and Sorbaria sorbifolia(L.)A.Br.Overall,tree richness is lower and its landscapes configuration is simple compared with the trees of high-altitude towns in Sanjiangyuan region.