摘要
生态系统的养分循环和养分供求平衡影响植物生态化学计量特征,碳(C)、氮(N)、磷(P)含量和计量比反映植物生理过程.青海省位于青藏高原东北部,了解该地区森林乔木各器官C、N、P含量及差异与养分分配机制对高原生态环境及其功能的维持有重要作用.以青海省不同地区森林中4个优势树种为对象,野外采集树种不同器官(叶片、树枝、树干、树根和树皮)测定C、N、P含量,分析青海省优势树种C、N、P含量分配及其生态化学计量特征.结果显示:(1)尖扎地区叶片中C含量和树枝中C、N、P含量都显著高于其他地区;而互助、大通、循化和祁连树皮中C含量最高;(2)门源地区树根N、P含量最低,叶片对N、P利用效率高;(3)高海拔地区树种叶片P含量高于低海拔地区,N含量则相反;(4)各地区优势树种各器官N/P < 14,主要受N元素限制.综上所述,植物在不同环境条件下采取的适应性机制不同,门源、尖扎地区植物叶片中C含量高,光合作用强,对N、P需求大且利用效率高;互助、大通、循化和祁连地区树皮中C含量最高,说明植物为抵御严寒气候采取保守生长策略;各地区植物生长在N元素限制条件下有较高的养分利用效率.
Nutrient cycling and the balance of nutrient supply and demand in ecosystems affect the eco-stoichiometric characteristics of plants. The content and ratios of C, N, and P reflect the physiological process of plants. Qinghai Province is located in the northeastern part of the Qinghai-Tibet Plateau. An understanding of the C, N, and P content and differences in various organs of forest trees and the distribution mechanism of nutrients is important to maintain the ecological environment and functions of the plateau. In this study, four dominant tree species were selected from forests in different areas of Qinghai Province. The content of C, N, and P in different organs (leaves, branches, trunks, roots, and bark) of field species at different regions was measured, to analyze the distribution of C, N, and P content and eco-stoichiometric characteristics of the dominant tree species in Qinghai Province. The results showed that: 1) the C content in leaves and C, N, and P content in branches in Jianzha area were significantly higher than those in other areas, while the C content in bark was highest in Huzhu, Datong, Xunhua, and Qilian. 2) The N and P content in roots was lowest in Menyuan, while the N and P utilization efficiency of leaves was high. 3) The P content in leaves of tree species at high altitude was found to be higher than that at low altitude, while N content showed the opposite trend. 4) The N/P < 14 in organs of the dominant tree species in different regions was mainly limited by N. In summary, plants adopt different adaptive mechanisms under different environmental conditions. In Menyuan and Jianzha, plant leaves have high C content, strong photosynthesis, high demand for N and P, and high utilization efficiency. The C content in bark of Huzhu, Datong, Xunhua, and Qilian is the highest, which indicate that plants adopted a conservative growth strategy to resist the severe cold climate. Plant growth in all regions has higher nutrient utilization efficiency under the N restriction.
作者
所尔阿芝
字洪标
罗雪萍
程瑞希
王艳丽
毛睿
王长庭
SUOER Azhi;ZI Hongbiao;LUO Xueping;CHENG Ruixi;WANG Yanli;MAO Rui;WANG Changting(College of Life Science and Technology, Southwest Minzu University, Chengdu 610041, China;Research Institute of the Qinghai Tibet Plateau, Southwest Minzu University, Chengdu 610041, China)
出处
《应用与环境生物学报》
CAS
CSCD
北大核心
2019年第4期783-790,共8页
Chinese Journal of Applied and Environmental Biology
基金
国家自然科学基金项目(31840707,31370542)
四川省重点研发项目(2018SZ0333)
中国科学院战略性先导科技专项(XDA05050207)
中央高校基本科研业务费专项资金(2018NZD13)
西南民族大学研究生“创新型科研项目”重点项目(CX2018SZ69)资助~~
关键词
优势树种
器官
生态化学计量
养分分配
乔木层
青海森林
dominant tree
organ
eco-stoichiometry
nutrient distribution
arbor layer
Qinghai forest
