植物生态学报 ›› 2022, Vol. 46 ›› Issue (4): 428-439.DOI: 10.17521/cjpe.2020.0385

• 研究论文 • 上一篇    下一篇

早春首次降雨时间及降雨量对古尔班通古特沙漠两种短命植物形态特征与叶绿素荧光的影响

张玉林1,2, 尹本丰1, 陶冶1, 李永刚1, 周晓兵1,*(), 张元明1,*()   

  1. 1中国科学院新疆生态与地理研究所, 荒漠与绿洲生态国家重点实验室, 乌鲁木齐 830011
    2中国科学院大学, 北京 100049
  • 收稿日期:2020-11-23 接受日期:2021-11-24 出版日期:2022-04-20 发布日期:2021-12-13
  • 通讯作者: 周晓兵,张元明
  • 基金资助:
    国家自然科学基金(41977099);新疆创新环境项目(2018Q009);新疆创新环境项目(2021D01E03);中国科学院青年创新促进会项目(Y201976)

Effects of the first rainfall timing and amount on morphological characteristics and chlorophyll fluorescence of two ephemeral species in the Gurbantünggüt Desert, northwestern China

ZHANG Yu-Lin1,2, YIN Ben-Feng1, TAO Ye1, LI Yong-Gang1, ZHOU Xiao-Bing1,*(), ZHANG Yuan-Ming1,*()   

  1. 1State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Ürümqi 830011, China
    2University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2020-11-23 Accepted:2021-11-24 Online:2022-04-20 Published:2021-12-13
  • Contact: ZHOU Xiao-Bing,ZHANG Yuan-Ming
  • About author:*(Zhou XB, zhouxb@ms.xjb.ac.cn) ;
  • Supported by:
    National Natural Science Foundation of China(41977099);Xinjiang Innovation Environment Project(2018Q009);Xinjiang Innovation Environment Project(2021D01E03);Youth Innovation Promotion Association of the Chinese Academy of Sciences(Y201976)

摘要:

早春降雨事件是影响荒漠短命植物生长的重要因子, 为了解古尔班通古特沙漠积雪完全融化后早春首次降雨时间及降雨量对短命植物光合生长的影响。该研究选取两种优势短命植物尖喙牻牛儿苗(Erodium oxyrhinchum)和琉苞菊(Centaurea pulchella)为研究对象, 设置3个首次降雨时间(积雪完全融化后第10、20和30天)和3个降雨水平(5、10和15 mm), 探究两物种的形态、生物量及光化学效率的响应差异。结果显示: 积雪完全融化后第10天进行首次降雨处理时, 随着首次降雨量的增加, 尖喙牻牛儿苗的叶面积和总生物量呈显著增加趋势, 最大光化学效率呈下降趋势。在第20和30天进行首次降雨处理时, 尖喙牻牛儿苗和琉苞菊的叶面积均呈显著增加趋势。在积雪完全融化后5 mm降雨处理时, 随着首次降雨时间的延迟, 尖喙牻牛儿苗和琉苞菊的最大光化学效率呈先下降后上升趋势; 10 mm降雨处理时, 尖喙牻牛儿苗的冠根比降低, 根长和总生物量呈先增加后下降趋势, 琉苞菊的根长呈显著增加趋势; 15 mm降雨处理时, 尖喙牻牛儿苗的叶面积、冠根比和最大光化学效率呈显著增加趋势; 琉苞菊的冠根比和最大光化学效率呈下降趋势, 总生物量呈显著增加趋势。尖喙牻牛儿苗和琉苞菊的根长分别与0-5 cm和5-10 cm土壤含水量呈显著正相关关系。这说明早春首次降雨量比首次降雨时间更能影响植株生长, 但不同物种对降雨格局变化的响应不一致, 这可能通过影响早春短命植物的形态特征, 进而影响早春荒漠生态系统的稳定性。

关键词: 荒漠短命植物, 首次降雨时间, 首次降雨量, 总生物量, 最大光化学效率

Abstract:

Aims Early spring rainfall event is an important factor affecting the growth of desert ephemeral plants. This study aims to understand the effects of the first rainfall timing and amount on the photosynthesis and growth of desert ephemeral plants in early spring.

Methods Two dominant ephemeral species, Erodium oxyrhinchum and Centaurea pulchella were selected in the Gurbantünggüt Desert, and treatments of three times of the first rainfall (10, 20 and 30 days after the snow melted completely) and three amounts of rainfall (5, 10 and 15 mm) were conducted. The plant morphology, biomass and chlorophyll fluorescence of the two plants were determined.

Important findings When the rainfall occurred on the 10th day after the snow melted completely, the leaf area and total biomass of the E. oxyrhinchum increased significantly with the rainfall amount, while the maximum photochemical efficiency decreased. If the rainfall was applied on the 20th and 30th day after the snow melted completely, the leaf area of the E. oxyrhinchum and C. pulchellaincreased significantly with the rainfall amount. On the other hand, if the treatments were applied with the addition of 5 mm rainfall, the maximum photochemical efficiency of the E. oxyrhinchum and C. pulchella decreased firstly and then increased significantly with the delay of the first rainfall timing. If the treatments were applied with the addition of 10 mm rainfall, the shoot to root ratio (S/R), root length and total biomass of the E. oxyrhinchum increased firstly and then decreased significantly with the delay of the first rainfall timing, but the root length of the C. pulchella increased significantly. If the treatments were applied with the addition of 15 mm rainfall, the leaf area, S/R and maximum photochemical efficiency of the E. oxyrhinchum increased with the delay of the first rainfall timing. For the C. pulchella, total biomass increased significantly, maximum photochemical efficiency and S/R decreased significantly with the delay of the first rainfall timing. The root length of the E. oxyrhinchum and C. pulchella were significantly positively correlated with soil moisture content of 0-5 cm and 5-10 cm, respectively. In general, the effects of the first rainfall amount on plant growth are much larger than effects of the first rainfall timing in early spring. However, different ephemeral species showed different trends with the changes in rainfall pattern. The variation in early spring rainfall caused by climate change can affect the morphological characteristics of desert ephemeral plants in desert, and then may affect the stability of desert ecosystem in early spring.

Key words: desert ephemeral plant, first rainfall timing, first rainfall amount, total biomass, maximum photochemical efficiency