摘要
非结构性碳水化合物(NSC)是植物碳光合产物的重要组分,在植物碳分配、逆境适应等方面起关键作用。近年来,全球变暖对青藏高原高寒草地生态系统的结构与功能造成了显著影响。以青藏高原的高寒草地为研究对象,选取了甘南、海北、那曲三个地区作为实验区,利用随海拔升高,环境胁迫逐渐增强这一特点,分析了四种植物功能群(禾草、莎草、豆科以及杂类草)对环境胁迫的NSC响应机制。研究结果显示:(1)高海拔地区的植物NSC含量显著高于低海拔地区;(2)豆科植物NSC含量显著低于其它三个功能群;(3)禾草类植物通过增加可溶性糖含量来响应胁迫;而莎草类植物则通过积累淀粉来响应胁迫。结果表明,面对环境胁迫(如高海拔代表的低温、强辐射等),高寒草地植物普遍通过提高NSC含量进行响应,但不同功能群采取了截然不同的碳分配策略以适应胁迫:豆科植物表现出较低的NSC投资,禾草侧重于增加可溶性糖以参与渗透调节增强抗逆性,而莎草则倾向于积累淀粉储存能量以备胁迫解除后生长之需。这些发现为理解全球气候变暖背景下青藏高原高寒草地植物对环境胁迫的响应机制提供了重要的科学依据,对于该区域生物多样性的保护和管理具有指导意义。
Non-structural carbohydrates(NSC)are critical components of plant photosynthetic products,playing key roles in carbon allocation and stress adaptation.Recent global warming has significantly impacted the structure and function of alpine grassland ecosystems on the Qinghai-Tibet Plateau.Using an elevation gradient(representing increasing environmental stress)in three regions—Gannan,Haibei,and Naqu,this study investigated the response mechanisms of NSC to environmental stress in four plant functional groups(grasses,sedges,legumes,and forbs)across alpine grasslands.Key findings include:(1)NSC content of plant at high elevations was significantly higher than low elevations.(2)Legumes exhibited significantly lower total NSC content than the other three functional groups.(3)Grasses responded to stress by significantly increasing soluble sugar content,while sedges responded by significantly accumulating starch content.These results demonstrated that alpine grassland plants generally elevated NSC levels under environmental stress(e.g.,low temperature and high radiation at high elevations).However,divergent carbon allocation strategies emerged:legumes deployed lower NSC investment;grasses prioritized soluble sugar accumulation for osmotic regulation to enhance stress tolerance;sedges favored starch storage to fuel post-stress regrowth.This study provides critical insights into how alpine grassland plants on the Qinghai-Tibet Plateau respond to environmental stress under global warming,offering a scientific basis for biodiversity conservation and ecosystem management.
作者
苗琪
孙芳慧
陈曦
才让拉毛
夏京
万玛措
袁婉凤
韩信
井新
索南吉
MIAO Qi;SUN Fanghui;CHEN Xi;CAI Ranglamao;XIA Jing;WAN Macuo;YUAN Wanfeng;HAN Xin;JING Xin;SUO Nanji(College of Life Sciences,Qinghai Normal University,Xining 810006,China;Qinghai Province Key Laboratory of Formation Mechanisms and Comprehensive Utilization of Biodiversity in the Qinghai-Xizang Plateau,Qinghai Normal University,Xining 810006,China;College of Grassland Agricultural Science and Technology,Lanzhou University,Lanzhou 730000,China)
出处
《生态学报》
北大核心
2026年第3期1221-1228,共8页
Acta Ecologica Sinica
基金
国家自然科学基金项目(32160285)。
关键词
非结构性碳水化合物
植物功能群
环境胁迫
碳分配策略
高寒草甸
non-structural carbohydrate
functional groups
environmental stress
carbon allocation strategy
alpine meadow
