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草业学报 ›› 2025, Vol. 34 ›› Issue (7): 145-157.DOI: 10.11686/cyxb2024333

• 研究论文 • 上一篇    

模拟增温对河西走廊典型荒漠灌木光合作用的影响

郭彬1(), 罗维成2, 单立山1(), 安宁2,3, 刘冰2   

  1. 1.甘肃农业大学林学院,甘肃 兰州 730070
    2.中国科学院西北生态环境资源研究院,干旱区生态安全与可持续发展全国重点实验室,中国科学院临泽内陆河流域研究站,甘肃 兰州 730000
    3.中国科学院大学,北京 100049
  • 收稿日期:2024-08-28 修回日期:2024-11-06 出版日期:2025-07-20 发布日期:2025-05-12
  • 通讯作者: 单立山
  • 作者简介:E-mail: shanls@gsau.edu.cn
    郭彬(2000-),男,甘肃庆阳人,在读硕士。E-mail: guo486246@163.com
  • 基金资助:
    国家自然科学基金项目(42177457);中国科学院西部青年学者项目资助

Effects of simulated warming on photosynthesis of typical desert shrubs in the Hexi Corridor

Bin GUO1(), Wei-cheng LUO2, Li-shan SHAN1(), Ning AN2,3, Bing LIU2   

  1. 1.Forestry College of Gansu Agricultural University,Lanzhou 730070,China
    2.Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,National Key Laboratory of Ecological Security and Sustainable Development in Arid Region,Linze Inland River Basin Research Station,Chinese Academy of Sciences,Lanzhou 730000,China
    3.University of Chinese Academy of Sciences,Beijing 100049,China
  • Received:2024-08-28 Revised:2024-11-06 Online:2025-07-20 Published:2025-05-12
  • Contact: Li-shan SHAN

摘要:

在全球气候变暖的背景下,西北地区气候趋于暖湿化,对植物的生长发育和生理生态过程产生重要影响。然而,气候变暖对荒漠植物光合作用的具体影响尚无一致结论。本研究以河西走廊典型荒漠灌木泡泡刺、梭梭、柠条和荒漠区植物柽柳为对象,利用不同高度(1.0、1.8和2.3 m)开顶式气室(OTC)模拟增温,探究典型荒漠灌木光合作用对增温的响应机制。结果表明:1)在植物生长季(4-9月),不同高度OTC使空气平均温度分别升高1.7、2.5和3.5 ℃,10 cm土壤温度升高0.6、1.2和1.8 ℃,40 cm土壤温度升高0.8、1.2和1.8 ℃。2)增温显著提高了C3植物泡泡刺、柽柳和柠条的净光合速率,但对C4植物梭梭的影响不显著,其中柠条的净光合速率随增温幅度增加先下降后上升。3)增温显著提高了泡泡刺、梭梭和柠条的气孔导度和胞间CO2浓度,而柽柳的气孔导度和胞间CO2浓度随增温幅度增加先升后降。4)增温显著提高了梭梭的蒸腾速率,柠条仅在最高温下显著提高,柽柳显著降低,而泡泡刺无显著变化。增温还显著提高了泡泡刺、柽柳和柠条的水分利用效率,但显著降低了梭梭的水分利用效率。4种植物的凌晨水势和正午水势均显著降低。综上所述,荒漠植物对增温表现出较强适应性,其中C4植物比C3植物在高温环境中更具优势。增温条件下,C4植物梭梭的蒸腾速率提高和水势降低有助于其水分吸收,维持光合作用稳定;而C3植物泡泡刺、柽柳和柠条的气孔导度和胞间CO2浓度的增加促进了光合作用。

关键词: 荒漠灌木, 光合作用, 模拟增温, 水分利用效率, 水势

Abstract:

With global climate warming, the climate in Northwest China is becoming increasingly warm and humid. This is significantly impacting plant growth and development, and physiological-ecological processes. However, the specific effect of climate warming on the photosynthesis of desert plants is still not fully understood. In this study, typical desert shrubs of the Hexi Corridor, including Nitraria sphaerocarpaHaloxylon ammodendron, and Caragana korshinskii, along with the desert plant Tamarix ramosissima, were grown in open top chambers (OTCs) of varying heights (1.0, 1.8, and 2.3 m) to simulate increased temperatures, and the photosynthetic responses of these typical desert shrubs to warming were investigated. The results indicated that: 1) During the plant growing season (April to September), the OTCs of 1.0, 1.8, and 2.3 m height increased the average air temperature by 1.7, 2.5, and 3.5 ℃, respectively; the soil temperature at 10 cm depth by 0.6, 1.2, and 1.8 ℃, respectively, and the soil temperature at 40 cm depth by 0.8, 1.2, and 1.8 ℃, respectively. 2) Warming significantly increased the net photosynthetic rate of the C3 plants N. sphaerocarpaT. ramosissima, and C. korshinskii, but had no significant effect on the C4 plant H. ammodendron. Under increasing temperature, the net photosynthetic rate of C. korshinskii initially decreased before increasing. 3) Warming significantly increased stomatal conductance and the intercellular CO2 concentration in N. sphaerocarpaH. ammodendron, and C. korshinskii; however, in T. ramosissima, the stomatal conductance and intercellular CO2 concentration initially increased before subsequently declining as the temperature increased. 4) Warming significantly increased the transpiration rate of H. ammodendron. The transpiration rate of C. korshinskii was increased only at the highest temperature, and that of T. ramosissima exhibited a significant decrease under increased temperatures. Warming did not significantly affect the transpiration rate of N. sphaerocarpa. Warming significantly enhanced the water use efficiency of N. sphaerocarpaT. ramosissima, and C. korshinskii, but significantly reduced that of H. ammodendron. The predawn and midday water potentials of all four plant species were significantly reduced under warming conditions. In summary, these desert plants exhibited strong adaptability to warming, with C4 plants demonstrating greater advantages over C3 plants in the high-temperature environments. Under warming conditions, the increased transpiration rate and reduced water potential of the C4 plant H. ammodendron facilitated its water absorption and stabilized photosynthesis, and the increase in stomatal conductance and intercellular CO2 concentration promoted photosynthesis in the C3 plants N. sphaerocarpaT. ramosissima, and C. korshinskii.

Key words: desert shrubs, photosynthesis, simulated warming, water use efficiency, water potential