二氧化碳浓度升高和根系分区交替灌溉的节水和养分利用的效应研究已有些证实，但对于二氧化碳升高环境下交替灌溉方式对土壤与作物系统中水分和矿质元素的汲取与分配过程及果实营养平衡的调控机理仍不清楚。本项目引入稳定碳氧同位素的指示和氮同位素的示踪技术，以土壤理化特性和酶活性为基础，重点围绕营养元素化学计量的响应研究，采用气候室试验定量监测和理论分析相结合的方法探究二氧化碳升高情景下交替灌溉对番茄气孔形态与水分利用的调节机理，明确土壤水分动态变化下根系对不同矿质营养吸收的影响方式，揭示从根系到果实中矿质元素运移和分配的内在调控关系，在此基础上进一步阐明二氧化碳升高下交替灌溉对果实内元素化学计量的改变途径和营养品质的调控机制，从而为作物节水、优质、高效的可持续发展提供更深层次的机理解释，对未来高二氧化碳环境下干旱半干旱农业区水分和养分高效利用的合理管理理论提供依据与支撑。

The effects of water-saving and nutrient utilization under elevated carbon dioxide concentration (e[CO2]) environment and alternate partial root-zone irrigation (PRI) have been partly confirmed, nonetheless the mechanism of PRI regime on absorption and distribution processes of water and mineral elements in soil-plant system, and fruit nutrient balance at e[CO2] still remains largely elusive. In this project, introducing the indication of carbon and oxygen isotope and trace of nitrogen isotope, forum on soil physicochemical property and enzymatic activity, and focus on response of nutrient element stoichiometry, the phytotron quantitative monitoring combined with theoretical analysis are presented to explore the mechanism of PRI strategy and on stomatal morphology and water use in tomato plant, clarify the way of roots influencing different minerals uptake under soil water dynamic, illuminate the intrinsic relationship of minerals transport and distribution from root to fruit under e[CO2] environment, and further elucidate the regulation mechanism of PRI on element stoichiometry and nutrient quality of tomato fruit in e[CO2] environment. This findings are anticipated to offer a deeper explanation for the sustainable development on achieving crop efficient irrigation and high quality, and further provide reasonable management theory on efficient utilization of water and nutrient resource for adapting to arid and semi-arid agricultural regions in future [CO2]-enriched environment.