Key message

Large differences were detected between genera and among species in chlorophyll pigment and macronutrient concentrations. Pines have greater variances than spruces and showed less downregulation of chlorophyll pigment concentrations than spruces in response to eCO₂ and DRT. There was strong genetic control of chlorophyll pigments and most macronutrients.

Abstract

Chlorophyll pigment and needle macronutrient concentrations were quantified for eight tree species in two commercially important genera, Pinus and Picea grown in a 2 × 2 factorial of atmospheric CO₂ (370 and 740 ppm) and soil moisture stress (− 0.1 to − 0.5 and − 0.7 to − 1.0 MPa) treatments. Four of the pines and three of the spruces are native to eastern North America, while a fourth spruce, Norway spruce (NS: Picea abies), is from Europe but has been widely used for reforestation in northeastern North America. Overall, spruces had significantly greater chlorophyll a, b, (CHLa, CHLb), and total chlorophyll concentration (TCC) and carotenoid concentration (CAR) than pines. Ambient CO₂ (aCO₂) had significantly greater TCC than in response to elevated CO₂ (eCO₂), and TCC and CAR was significantly downregulated more in spruces than in pines in response to eCO₂. Pines had equal or greater TCC and CAR in response to drought treatment (DRT) than well-watered treatment, whereas spruces had significantly lower values in response to DRT. Needle N, P and Ca concentrations were greater for spruces than pines. Needle N concentrations declined in response to both eCO₂ and DRT. Needle P increased in response to eCO₂ but declined in response to DRT. Using total biomass as a covariate, needle N showed no response in pines; whereas spruces showed a slight positive response to increasing total biomass. Covariate analysis showed that TCC had a significant positive relationship to needle N and Mg, with greater TCC in spruces than in pines for a given needle N. Photosynthetic quantum efficiency (QE), derived from light response curves, had a significant positive relationship to TCC that was greater in pines than in spruces for a given TCC. Photosynthetic light convexity had a significant positive relationship to TCC that was also greater in pines than in spruces for a given TCC, indicating a sharper curvature compared to a more progressive curve for spruce. Pine species have greater variances than spruce species. While Pinus strobus (white pine, subgenus Strobus) stands out as having greater chlorophyll and nutrient concentrations than the other three pines (subgenus Pinus). Overall, pines showed less downregulation of chlorophyll pigment concentrations than spruces in response to eCO₂ and DRT. There was strong genetic control for chlorophyll pigments and most macronutrients.

中文翻译：

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八种松树和云杉树种的叶绿素色素和针状常量营养素对土壤水分和大气 CO2 处理的响应和相互作用

关键信息

在叶绿素色素和常量营养素浓度方面，在属和​​种之间检测到很大差异。松树比云杉具有更大的差异，并且在响应 eCO ₂和 DRT 时显示出比云杉更少的叶绿素色素浓度下调。叶绿素色素和大多数常量营养素受到强烈的遗传控制。

抽象的

叶绿素色素和针常量营养素浓度两个商业上重要的属八个树种量化，松和云杉在2×2阶乘大气CO的生长₂（370和740 ppm的）和土壤水分应力（ - 0.1〜 - 0.5和- 0.7 至 - 1.0 MPa) 处理。其中四种松树和三种云杉原产于北美东部，而第四种云杉，挪威云杉（NS：Picea abies）来自欧洲，但已广泛用于北美东北部的重新造林。总体而言，云杉的叶绿素a、b、（CHL a、CHL b)，总叶绿素浓度 (TCC) 和类胡萝卜素浓度 (CAR) 比松树高。环境 CO ₂ (aCO ₂ ) 的 TCC 显着高于响应升高的 CO ₂ (eCO ₂ )，并且在响应 eCO _{2 时}，云杉中的 TCC 和 CAR 比松树中的显着下调更多。松树对干旱处理 (DRT) 的 TCC 和 CAR 的响应值等于或大于浇水充足的处理，而云杉对 DRT 的响应值显着较低。云杉的针叶 N、P 和 Ca 浓度高于松树。针头 N 浓度随着 eCO ₂和 DRT 的变化而下降。针 P 增加以响应 eCO ₂但在回应 DRT 时拒绝了。使用总生物量作为协变量，针叶氮在松树中没有表现出响应；而云杉对增加总生物量表现出轻微的积极反应。协变量分析表明，TCC 与针状 N 和 Mg 呈显着正相关，对于给定的针状 N，云杉的 TCC 比松树中的 TCC 大。光合量子效率 (QE)，来自光响应曲线，与 TCC 呈显着正相关对于给定的 TCC，松树比云杉更大。光合光凸度与 TCC 具有显着的正相关关系，对于给定的 TCC，松树的光凸度也大于云杉，表明与云杉的渐进曲线相比，其曲率更锐利。松树物种比云杉物种具有更大的差异。虽然松（白松，Strobus亚属）比其他三种松树（松属亚属）具有更高的叶绿素和营养浓度。总体而言，松树对 eCO ₂和 DRT 的响应比云杉显示出较少的叶绿素色素浓度下调。叶绿素色素和大多数常量营养素受到强烈的遗传控制。