Chenjun Du1, Xiaodan Wang2, Mengyao Zhang1, Jie Jing1, Yongheng Gao3. 1. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China. 2. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China. 3. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China. Electronic address: yhgao@imde.ac.cn.
Abstract
A substantial number of experiments have so far been carried out to study the response of the C-N-P stoichiometry of terrestrial plants to the rising CO2 level of the earth. However, there is a need of systematic evaluation for assessing the impact of the elevated CO2 on plant C-N-P stoichiometry. In the present investigation, a comprehensive meta-analysis involving 386 published reports and including 4481 observations has been carried out. The goal of the research was to determine the response of plants to their C-N-P stoichiometry due to elevated levels of global atmospheric CO2. The results showed that rising CO2 altered the concentration of C (+2.19%, P < 0.05), N (-9.73%, P < 0.001) and P (-3.23%, P < 0.001) and C:N (+13.29%, P < 0.001) and N:P ratios (-7.32%, P < 0.0001). Overall, a slightly increasing trend in the C:P ratio (P > 0.05) in the plant was observed. However, plant leaf, shoot and herbaceous type of plants showed more sensitivity to rising CO2. CO2 magnitude exhibited a positive effect (P < 0.05) on C:N ratio. Additionally, "CO2 acclimation" hypothesis as proposed by the authors of the current paper was also tested in the study. Results obtained, especially, show changes of C and N concentrations and C:P ratio to an obvious down-regulation for long-term CO2 fumigation. At spatial scales, a reduction of plant N concentration was found to be higher in the southern hemisphere. The CO2 enrichment methods affected the plant C-N-P stoichiometry. Compared to FACE (free-air CO2 enrichment), OTC (open top chamber) showed larger changes of C, N, P, and N:P. The results of the present study should, therefore, become helpful to offer a better understanding towards the response of the terrestrial plant C-N-P stoichiometry to an elevated global atmospheric CO2 in the future.
A substantial number of experiments have so far been carried out to study the response of the class="Chemical">C-N-P stoichiometry of terrestrial class="Chemical">plants to the rising class="Chemical">pan class="Chemical">CO2 level of the earth. However, there is a need of systematic evaluation for assessing the impact of the elevated CO2 on plant C-N-P stoichiometry. In the present investigation, a comprehensive meta-analysis involving 386 published reports and including 4481 observations has been carried out. The goal of the research was to determine the response of plants to their C-N-P stoichiometry due to elevated levels of global atmospheric CO2. The results showed that rising CO2 altered the concentration of C (+2.19%, P < 0.05), N (-9.73%, P < 0.001) and P (-3.23%, P < 0.001) and C:N (+13.29%, P < 0.001) and N:P ratios (-7.32%, P < 0.0001). Overall, a slightly increasing trend in the C:P ratio (P > 0.05) in the plant was observed. However, plant leaf, shoot and herbaceous type of plants showed more sensitivity to rising CO2. CO2 magnitude exhibited a positive effect (P < 0.05) on C:N ratio. Additionally, "CO2 acclimation" hypothesis as proposed by the authors of the current paper was also tested in the study. Results obtained, especially, show changes of C and N concentrations and C:P ratio to an obvious down-regulation for long-term CO2 fumigation. At spatial scales, a reduction of plant N concentration was found to be higher in the southern hemisphere. The CO2 enrichment methods affected the plant C-N-P stoichiometry. Compared to FACE (free-air CO2 enrichment), OTC (open top chamber) showed larger changes of C, N, P, and N:P. The results of the present study should, therefore, become helpful to offer a better understanding towards the response of the terrestrial plant C-N-P stoichiometry to an elevated global atmospheric CO2 in the future.