CO2倍增条件下不同生育期水稻碳氮磷含量及其计量比特征  

Effect of CO_2 Doubling and Different Plant Growth Stages on Rice Carbon,Nitrogen,and Phosphorus and Their Stoichiometric Ratios

作　　者：唐美玲 肖谋良[2] 袁红朝[2] 王光军[1] 刘守龙[2] 祝贞科[2] 葛体达[2] 吴金水[2] TANG Mei-ling;XIAO Mou-liang;YUAN Hong-zhao;WANG Guang-jun;LIU Shou-long;ZHU Zhen-ke;GE Ti-da;WU Jin-shui(College of Life Science and Engineering,Central South University of Forestry and Technology,Changsha 410004,China;Key Laboratory of Agro-ecological Processes in Subtropical Region,Institute of Subtropical Agriculture,Chinese Academy of Sciences,Changsha 410125,China)

机构地区：[1]中南林业科技大学生命科学与技术学院,长沙410004 [2]中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室 [3],长沙410125

出　　处：《环境科学》2018年第12期5708-5716,共9页Environmental Science

基　　金：国家自然科学基金项目(41771334,41771337)

摘　　要：生态化学计量比的变化特征在一定程度上可反映植物对环境条件变化适应的本质.本研究利用CO_2连续标记系统模拟大气CO_2体积分数升高(800×10-6)条件,探讨水稻各器官C、N、P含量及其计量比变化的特征.结果表明,CO_2倍增促进水稻各器官生长,并增加了根冠比.在植株生长过程中CO_2倍增可一定程度上降低不同生育期内秸秆全氮(TN)含量,同时使得水稻根系、秸秆和籽粒的C/N比值增大,降低N和提高P的利用效率.多重比较和韦恩图分析表明CO_2体积分数仅对水稻秸秆TN有着显著影响,对水稻养分含量及其计量比特征的变异解释率均为-1. 0%,即几乎不受CO_2倍增影响.在大气CO_2体积分数升高条件下,水稻各器官C、N、P含量及其计量比具有良好的计量学内稳性特征,同时在不同生育期内其计量比变化特征与"生长速率理论"相符.在农田管理措施中,可适当施加氮肥来缓解CO_2体积分数升高带来的养分平衡压力.The variation characteristics of ecological stoichiometric ratios can reflect the nature of plant adaptation to environmental changes. The C, N, and P contetns, and their stoichiometric ratios in different organs of rice were studied using a CO2 continuous labeling system, by simulating the increase of atmospheric CO2 concentration （800×10^-6）. The results showed that CO2 doubling promoted the growth of rice organs and increased the root/shoot ratio. CO2 doubling reduced the shoot TN content in different growth periods, increased the C/N ratio in the rice root, shoot, and grain, decreased the N use efficiency, and improved the P use efficiency. Multiple comparison and Venn diagram analyses showed that CO2 concentration only has a significant impact on the TN content in the rice shoot; it contributed little to the variation in rice nutrient content and their stoichiometric ratios, indicating that CO2 doubling had no effect on these. Under the condition of elevated atmospheric CO2 concentrations, the C, N, and P contents and their stoichiometirc ratios, in rice organs had good homeostasis, and the stoichiometrie change during growth periods was consistent with ＂the Growth Rate Theory＂. In farmland management, appropriate nitrogen fertilizers can alleviate the nutrient balance pressure caused by the increase in CO, concentration.

关 键 词：生态化学计量学 CO2倍增 生育期 动态平衡理论 生长速率理论 

分 类 号：X171[环境科学与工程—环境科学]