干旱区研究 ›› 2011, Vol. 28 ›› Issue (5): 839-848.

• 植物生态与植物地理 • 上一篇    下一篇

鄂尔多斯高原藏锦鸡儿(Caragana tibetica)个体层次对干旱的生态适应性

 张璞进, 杨劼, 赵利清   

  1. 内蒙古大学 生命科学学院,内蒙古 呼和浩特 010021
  • 收稿日期:2010-09-14 修回日期:2010-11-18 出版日期:2011-09-15 发布日期:2011-10-16
  • 通讯作者: 杨劼.E-mail:Jyang@mail.imu.edu.cn
  • 基金资助:

    内蒙古自治区科学技术项目重大专项(20091402)和内蒙古自然科学基金重大项目(20080404ZD06)

Ecological Adaptability of Caragana tibetica Individuals in the Ordos Plateau

 ZHANG  Pu-Jin, YANG  Jie, ZHAO  Li-Qing   

  1. College of Life Sciences, Inner Mongolia University, Hohhot 010021, China
  • Received:2010-09-14 Revised:2010-11-18 Online:2011-09-15 Published:2011-10-16
  • Supported by:

    张璞进(1981-),男,在读博士,从事草地生态学相关研究.E-mail:Zhangpujin0819@163.com

摘要: 藏锦鸡儿(Caragana tibetica)群落是草原与荒漠过渡带上的一个地带性植物群落类型,分布面积大,是牧草地重要的环境保护屏障。通过野外观察,对藏锦鸡儿地上部分和地下部分的形态特征以及沙堆内外的土壤水分进行了测定;采集藏锦鸡儿的根和茎的样品,在室内分析根和茎的劈裂现象。结果显示:研究区藏锦鸡儿个体平均长57 cm,宽44 cm,高22 cm;沙堆平均长77 cm,宽52 cm,高16 cm,体积0.071 m3。藏锦鸡儿分枝密集,次级分枝数约为上级分枝数的2~3倍;在沙堆内各级枝条约2/3枯死,枝条长度在8~10 cm。沙堆表面枝条无明显节间,每100 cm2内约含18个小枝。根冠比在0.35~0.53之间,根系为双层根系类型,小根和细根在20~60 cm土层所占比例最高,土壤水分在20~60 cm土层也最高。藏锦鸡儿形成的沙堆对地上部分具有支撑和保护作用,沙堆内生有不定根;根和茎具有劈裂现象,表明藏锦鸡儿对干旱环境具有很好的适应性。

关键词: 藏锦鸡儿(Caragana tibetica), 沙堆, 垫状灌木, 茎, 根系, 劈裂现象, 鄂尔多斯高原

Abstract: A peculiar ecotone forms in the arid and semiarid Ordos Plateau of China, and it provides an important habitat for diverse shrub communities that play an important role in maintaining the desert ecosystem and sustaining the local stock raising. Caragana tibetica community is a zonal vegetation type in this grasslanddesert ecotone. It occupies a largest area constituting an important rangeland and contributing to ecological stability in this region. We investigated the morphological characteristics of aboveground part of C. tibetica individuals. Underground part was studied only for the selected medium and small sized individuals. Soil moisture content inside and outside of C. tibetica nebkhas was measured, sand landforms were distributed around shrubs, and fissuration of roots and stems of C. tibetica was examined. We found that the individuals of C. tibetica were 57 cm long, 44 cm wide and 22 cm tall in average. Nebkhas were 77 cm long, 52 cm wide and 16 cm high in average, and their average volume was 0.071 m3. It was found that 18 thick stems of C. tibetica emerged from each nebkha surface in average. The length of stems buried in nebkhas varied in a range of 8-10 cm for each class with about 2/3 of them being dead. Number of stems in the lower class was 2-3 times higher than that in the higher class. Roots were stratified into two layers. In addition, stems buried in nebkhas grew adventitious roots. The rootshoot ratio varied in a range of 0.35-0.53. Generally, the soil layer of 20-60 cm in depth is characterized by small and fine roots and higher soil moisture content. Nebkhas play an important role in supporting and protecting aboveground part of C. tibetica. Stems and roots of the shrub are also characterized by the interesting phenomenon of fissuration. Our findings indicate that morphological characteristics of  C. tibetica are developed as a result of adaptability of C. tibetica to drought environment.

Key words: Caragana tibetica, nebkha, cushion shrub, stem, root, fissuration, Ordos Plateau

中图分类号: 

  • Q948.1123