塔里木河中游天然植被的数量分类与排序研究

Quantitative Classification and Ordination Analysis on Vegetation in the Middle Reaches of Tarim River

通过塔里木河中下游天然植被带的调查研究 ,应用数量分类 (TWINSPAN)和排序 (CCA)方法 ,对塔里木河中下游地区天然植被类型进行了划分 ,并探讨了决定该地区天然植物群落类型的主要环境因子。该地区天然植被可分为 4个植被型组 ,4个植被型 ,6种植被亚型 ,9个群系 ,15个群丛。通过对 8个环境因子的CCA排序分析 ,结果表明制约塔里木河中下游天然植被组成和结构的主导环境因子为地下水位、地下水矿化度、地下水酸碱度。通过CCA二维排序图将 16种植物对干旱、盐碱的适应性划分 5类型。 2 1个样地在CCA二维排序图上可聚集成 9个植物群落类群 ,即胡杨 (Populuseuphratica)群落、铃铛刺 (Halimodendronhalodendron)群落、库尔勒沙拐枣(CalligonumKuerlese)群落、多枝柽柳 (Tamarixramosissima )群落、黑果枸杞 (Lyciumruthenicum)群落、盐穗木(Halostashyscaspica)群落、花花柴 (Kareliniacaspica)群落、疏叶骆驼刺 (Alhagisparsifolia)群落、罗布麻(Apocynumvenetum)群落 ,与TWINSPAN结果中的群系分类单位一致。CCA连续排序与TWINSPAN分类结果吻合较好。 9种植物群落类型中 ,能耐受最大盐胁迫的为盐穗木群落 ,能耐受最大干旱胁迫的为铃铛刺群落 ,能耐受最大地下水碱胁迫的为黑果枸杞群落。

Based on the data obtained from 21 plots of natural plant community and 16 plant species in the middle reaches of Tarim River of China, quantitative classification (TWINSPAN) and ordination (CCA) methods were used. The natural plant communities are classified and the major environmental variables that correlated with the natural plant community types are discussed. TWINSPAN results show that the natural plant communities in the middle and lower reaches of Tarim River can be divided into 15 groups which belonged to 4 Vegetation type groups, 4 Vegetation types, 6 Vegetation subtypes, 9 Formations. CCA was combined with 8 environmental variables. The results of CCA ordination reflect sufficiently the relationship between vegetation and groundwater depth, groundwater pH and groundwater degree of mineralization Five groups are identified from 16 plant species by their compatibility to endure drought and salt-alkali. The gathered groups of 21 plant plots in CCA ordination are consistent with the result of quantitative classification (TWINSPAN) in formation class. The results of the two analysis methods were in good agreement. Nine types of plant communities are Populus euphratica forest, Halimodendron harodendron shrubland, Calligonum Kuerlese forest, Tamarix ramosissima shrubland, Lycium ruthenicum shrubland, Halostashys caspica shrubland, Karelinia caspica community, Alhagi sparsifolia community, Apocynum venetum community . Among nine types of plant communities Halostashys caspica shrubland can endure the highest salt stress, Halimodendrom halodendron shrubland can endure the highest drought stress and Lycium ruthenicum shrubland can endure the highest alkali stress of the groundwater.