Effect of CO_2 concentration on photosynthesis in deciduous broad-leaved tree species

CO_2浓度对落叶阔叶树种光合作用的影响

• 批准号: 03660150
• 负责人: MARUYAMA Koohei
• 金额: $ 1.41万
• 依托单位: Niigata Univ.
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-03660150/
• 关键词: Photosynthesis rate; CO_2 concentration effect; Decidous broad-leaved tree species; Temperature effect; Water stress effect; Conductance; 個葉レベル; 水ポテンシャル; 水ストレス; 個体レベル; 短期処理効果

(1) Effects of CO_2 levels on net photosynthesis of single leaf in several deciduous broad-leaved tree species : P_n and the saturated PAR were generally increased with inceasing CO_2 levels in most species tested. From the light-photosynthesis curves, we classified fagus crenate(Fc) as low CO_2-weak light use type, Zelkova serrata(Zs) as high CO_2-weak light use type, Alnus firma(Af) as high CO_2-strong light use type, and Ginkgo biloba(Gb) as high CO_2-intermediate type.(2) Effects of short-term CO_2 levels and temperatures on the photosynthesis and respiration of some deciduous broad-leaved tree species seedlings : Temperature-photosynthesis curves in strong light showed a distinct optimum curves. The optimum temperatures were found at 15-35ﾟC, the values shifted from low to high temperatures with increasing CO_2 levels. Among five species, Af & W.hortensis(Wh), shrub species, had a higher P_n and the broad optimum ranges. Fc, Qc & Gb, tree species, exhibited a contrasting pattern. (3) Effects of CO_2 levels on a leaf photosynthesis in Qc, Q.dentata(Qd) and Wh seedlings : CO_2 levels that saturated P_n were found above 900ppm in 2Quercus species, and 600ppm in Wh. The water use efficiency enhanced with higher CO_2 levels irrespective of species.(4) Effects of high CO_2 levels and water stress on gas exchange in Alnus firma : The rates of Pn, Tr and g_s decreased with increasing water stress. The critical water potentials were found at -12, -10, -8 bars, respectively. COn_2 effects were observed in Pn and g_s under well-watered conditions above -8 bar water potentials.

(1) CO_2水平对几种落叶阔叶树单叶净光合作用的影响：大多数树种的P_n和饱和PAR均随CO_2水平的升高而升高。从光-光合作用曲线上，我们将麻豆（fagus crenate, Fc）划分为低co_2 -弱光利用型，泽尔科瓦（Zelkova serrata, Zs）划分为高co_2 -弱光利用型，桤木（Alnus firma, Af）划分为高co_2 -强光利用型，银杏（Ginkgo biloba, Gb）划分为高co_2 -中间型。(2)短期CO_2水平和温度对部分落叶阔叶树幼苗光合和呼吸的影响：强光条件下温度-光合曲线表现出明显的最优曲线。在15 ~ 35℃的温度下，随着CO_2浓度的增加，温度由低到高。5个树种中，灌丛树种（af&w .hortensis, Wh）的P_n值较高，且最适范围较宽。不同树种Fc、Qc和Gb表现出不同的变化规律。(3) CO_2浓度对Qc、Qd和Wh幼苗叶片光合作用的影响：2种栎的CO_2浓度大于900ppm， Wh的CO_2浓度大于600ppm。水利用效率随CO_2浓度的升高而提高。(4)高CO_2水平和水分胁迫对桤木气体交换的影响：Pn、Tr和g_s速率随水分胁迫的增加而降低。临界水势分别为-12、-10、-8 bar。在水势高于-8 bar的条件下，在Pn和g_s中观察到COn_2效应。