Gas exchange characteristics of wheat stands grown in a closed, controlled environment

Information on gas exchange of crop stands grown in controlled environments is limited, but is vital for assessing the use of crops for human life-support in closed habitats envisioned for space. Two studies were conducted to measure gas exchange of wheat stands (Triticum aestivum L. cv. Yecora Rojo) grown from planting to maturity in a large (20 m2 canopy area), closed growth chamber. Daily rates of dark-period respiration and net photosynthesis of the stand were calculated from rates of CO2 build-up during dark cycles and subsequent CO2 drawdown in the light (i.e., a closed-system approach). Lighting was provided as a 20-h photoperiod by high-pressure sodium lamps, with canopy-level photosynthetic photon flux density (PPFD) ranging from 500 to 800 micromoles m-2 s-1 as canopy height increased. Net photosynthesis rates peaked near 27 micromoles CO2 m-2 s-1 at 25 d after planting, which corresponded closely with stand closure, and then declined slowly with age. Similarly, dark-period respiration rates peaked near 14 micromoles CO2 m-2 s-1 at 25 d and then gradually declined with age. Responses to short-term changes in irradiance after canopy closure indicated the stand light compensation point for photosynthesis to be near 200 micromoles m-2 s-1 PPFD. Tests in which CO2 concentration was raised to approximately 2000 micromoles mol-1 and then allowed to draw down to a compensation point showed that net photosynthesis was nearly saturated at > 1000 micromoles mol-1; below approximately 500 micromoles mol-1, net photosynthesis rates dropped sharply with decreasing CO2. The CO2 compensation point for photosynthesis occurred near 50 micromoles mol-1. Short-term (24 h) temperature tests showed net photosynthesis at 20 degrees C > or = 16 degrees C > 24 degrees C, while dark-period respiration at 24 degrees C > 20 degrees C > 16 degrees C. Rates of stand evapotranspiration peaked near Day 25 and remained relatively constant until about Day 75, after which rates declined slowly. Results from these tests will be used to model the use of plants for CO2 removal, O2 production, and water evaporation for controlled ecological life support systems proposed for extraterrestrial environments.     

Carbon dioxide effects on potato growth under different photoperiods and irradiance

Carbon dioxide concentration can exert a strong influence on plant growth, but this influence can vary depending on irradiance. To study this, potato plants (Solanum tuberosum L.) cultivars Norland', Russet Burbank', and Denali' were grown in controlled-environment rooms at different levels of CO2 and irradiance. Carbon dioxide levels were maintained either at 350 or 1000 micromoles mol-1 and applied in combination with 12- or 24-h photoperiods at 400 or 800 micromoles m-2 s-1 photosynthetic photon flux. Air temperatures and relative humidity were held constant at 16 degrees C and 70%, respectively, and plants were harvested 90 d after planting. When averaged across all cultivars, CO2 enrichment increased tuber yield and total plant dry weight by 39 and 34%, respectively, under a 12-h photoperiod at 400 micromoles m-2 s-1; 27 and 19% under 12 h at 800 micromoles m-2 s-1; 9 and 9% under 24h at 400 micromoles m-2 s-1. It decreased dry weights by 9 and 9% under 24 h at 800 micromoles m-2 s-1. Tuber yield of Denali showed the greatest increase (21%) in response to increased CO2 across all irradiance treatments, while tuber yields of Russet Burbank and Norland were increased 18 and 9%, respectively. The results show a pattern of greater plant growth from CO2 enrichment under lower PPF and a short photoperiod.     

斑皮柠檬桉不同种源光合特性比较分析

以斑皮柠檬桉10个种源的苗木为研究材料,测定分析其光响应曲线和特定光强的光合参数。结果表明:光饱和点最大的2个种源19694和20756达到1 700μmol.m-2.s-1,最小的是种源20883,光饱和点为1 333.33μmol.m-2.s-1。种源19666、19691和20883光补偿点最低,低于14.0μmol.m-2.s-1,利用弱光的能力最强;种源19664、19665和20787光补偿点超过40μmol.m-2.s-1,对弱光的利用能力相对较差,种源19691、19694和19666光饱和点较高,光补偿点较低,对光环境的适应范围较大。光强为1 500μmol.m-2.s-1时,10个种源的斑皮柠檬桉的净光合速率、气孔导度、胞间二氧化碳和蒸腾速率的差异都达到显著水平;光合特征参数与种源地地理信息的相关关系均未到达显著水平;种源19694、19665和20756属于高净光合速率较高水分利用效率的类型,种源19691属于高净光合速率低水分利用效率的类型;种源19666和20883属于低净光合速率高水分利用效率的类型;相关分析表明,经度、纬度和海拔对斑皮柠檬桉的光合特征参数均未起到主导作用。通过比较分析不同种源斑皮柠檬桉的光合作用差异性,以便在造林时根据环境、地形、地貌选择合适的种源。     

Modeling the effects of light, carbon dioxide, and temperature on the growth of potato

This study examined the effects of light, temperature and carbon dioxide on the growth of potato (Solanum tuberosum L.) in a controlled environment in order to ascertain the best growing conditions for potato in life support systems in space. 'Norland' and 'Russet Burbank' were grown in 6-L pots of peat-vermiculite for 56 d in growth chambers at the University of Wisconsin Biotron. Environmental factor levels included continuous light (24-h photoperiod) at 250, 400, and 550 micromoles m-2 s-1 PPF; constant temperature at 16, 20, and 24 degrees C; and CO2 at approximately 400, 1000, and 1600 microliters L-1. Separate effects analysis and ridge analysis provided a means to examine the effects of individual environmental factors and to determine combinations of factors that are expected to give the best increases in yields over the central design point. The response surface of Norland indicated that tuber yields were highest with moderately low temperature (18.7 degrees C), low CO2 (400 microliters L-1) and high light (550 micromoles m-2 s-1 PPF). These conditions also favored shorter stem growth. Russet Burbank tuber yields were highest at moderately low temperature (17.5 degrees C), high CO2 (1600 microliters L-1) and medium analyses will be used to project the most efficient conditions for growth of potatoes in closed ecological life support systems (CELSS) in space colonies.     

Developmental Responses of Wheat cv. Norin 61 to Fluence Rate of Green Light

Summary

Wheat (Triticum aestivum L. cv. Norin 61) plants were grown under five different photon flux densities obtained by modulating the number of green light-emitting diodes (LEDs) under white fluorescent lamps. The experiment was conducted under continuous irradiation at a constant temperature of 20°C to clarify the developmental responses of wheat to the fluence rate of green light. The higher the photon flux density of green light, the shorter the number of days from emergence to heading. The earliest heading was observed in the plants grown under 496 green LEDs, 32.0 days after emergence. A significant logarithmic function could fit the relationship between the fluence rate of green light and developmental rate. In this report, principal component analysis (PCA) was adopted to analyze the confounding of green light versus photosynthetic photon flux density (PPFD) with 17 developmental and morphological traits. The eigenvalues explained were 5.64, 3.20, and 2.61, respectively, for the first, second and third principal components (PCs). The first PC was assumed as the factor related to the isometric growth, and the third PC was assumed as the factor related to the developmental rate and culm elongation. Therefore, it was supposed that the first and third PCs were affected by the PPFD and the photon flux density of green light, respectively. The results suggested that the fluence rate of green light affects the development of wheat as a signal source. Furthermore, the development of wheat was promoted by the green light independent of PPFD.     

茶树新品种桂绿1号光合特性初步研究

采用Li-6400便携式光合测定系统对茶树新品种桂绿1号的光合-光响应曲线和光合日变化进行了测定分析。结果表明,在夏季晴天条件下,桂绿1号净光合速率（Pn）日变化呈单峰曲线,峰值出现在11:00,约为9.36βμmol·m^-2·s^-1;蒸腾速率（Tr）的日变化也为单峰曲线,但其最大值出现在15:00,约为4.06βmmol·m^-2·s^-1。该品种的光饱和点与光补偿点分别为354.60βμmol·m^-2·s^-1和7.13βμmol·m^-2·s^-1,表观量子效率（Φ）为0.088βmol·mol^-1。逐步多元回归分析表明,光合有效辐射和空气相对湿度是直接影响桂绿1号茶树净光合速率日变化的主要因子。该研究为桂绿1号的引种、速生丰产和制定栽培管理措施提供理论依据。     

生菜苗期生长最优光照模式的模糊综合评判

为探讨不同光照模式对生菜苗期生长和品质的影响,以荧光灯为对照（CK）,采用发光二极管（LED）调控光谱能量分布,设计LED红蓝配比（7:3、5:5、3:7）、光周期（12L/12D、16L/8D、20L/4D）及光照强度(100、150、200μmol·m-2·s-1)3因素3水平的正交试验,共9个试验处理组。以"意大利"全年耐抽薹生菜为材料,测定苗期生长和品质相关的指标,采用层次分析法（AHP）确定各生长和生理指标的权数,通过模糊数学原理对生菜苗期生长进行综合评价分析。结果表明:生菜苗期株高、茎粗、下胚轴长、整株鲜重、叶绿素、可溶性糖、可溶性蛋白质和硝酸盐的权重依次为0.101 8、0.046 6、0.078 0、0.273 6、0.148 7、0.054 8、0.054 8和0.241 8。综合评价结果为红蓝配比为5:5、光周期为20L/4D、光强为100μmol·m-2·s-1的光照模式栽培效果最好,其次是红蓝配比为7:3、光周期为20L/4D、光强为200μmol·m-2·s-1的光照模式。层次分析法对生菜不同光照模式的栽培效果的综合评价有较好的适应性,有助于获得南方设施工厂化生菜育苗最佳的光照模式。     

夜间补光对小麦叶片激素含量及光合特性的影响

为探究夜间补光对小麦生育后期的调控作用,以冬小麦品种豫农186为材料,以自然光照时间为对照,在小麦抽穗后设置夜间人工补光2h、4h和6h三个处理,研究补光时间对小麦叶片内源激素含量、光合特性及产量的影响。结果表明,夜间补光可增加小麦叶面积及旗叶叶绿素含量和光合速率,以补光6h的效果最显著。与自然对照相比,夜间补光显著增加旗叶GA3、IAA、ZR含量,且激素含量的升高幅度随补光时间的延长而增加,但ABA含量受影响较小。夜间补光能显著提高灌浆前期和中期籽粒灌浆速率及千粒重和产量,其中补光6h处理的最大灌浆速率比自然对照增大16.21%,产量提高14.07%。说明小麦抽穗后适当延长光照时间有利于叶片的生长发育,可提高激素含量和光合效率,促进籽粒灌浆,增加产量。     

Effect of Light Quality on Developmental Rate of Wheat under Continuous Light at a Constant Temperature

Abstract

The developmental rate of wheat was investigated under continuous light of eight different qualities (in eight plots) obtained by combining three out of four different kinds of fluorescent lamps (white, blue, purplish red and ultraviolet-A) at a constant temperature of 20°C. A Japanese spring wheat var. Norin 61 and a winter wheat var. Shun-yo were used.The number of days from seeding to heading varied extensively with the variety and the light quality. The first heading wasobserved in the plot under three white fluorescent lamps (W + W + W) at 37 and 81 days after seeding in Norin 61 and Shun-yo, respectively. The developmental rate in both cultivars was significantly correlated with the ratio of energy in 500–550 nm range (green light) and 600–700 nm range (red light) to that in the whole spectral range (250–1,000 nm). These results suggest that green and red lights play important roles in the regulation of the developmental rateindependent of photoperiodism and vernalization.     

灰色关联分析法对叶用莴苣生长期光环境的优化

为保证设施叶用莴苣周年生产的供给,研究了人工气候条件下不同光照模式对叶用莴苣生长期生长特性的影响,以确定叶用莴苣生长的最优光环境,实验以‘意大利’全年耐抽薹叶用莴苣（Lactuca sativa L.）为试材,设计 LED 红蓝配比（7:3、5:5、3:7）、光周期（12L/12D、16L/8D、20L/4D）及光照强度[100 μmol/(m2·s)、150 μmol/(m2·s)、200 μmol/(m2·s)]的 3 因素 3 水平正交实验,利用灰色关联分析法分析不同光照模式对生长期叶用莴苣植株的生长、光合色素含量及营养品质的影响。结果表明,不同处理对叶用莴苣生长期生长及品质的影响不同。相比于其他光环境条件,处理 9[红蓝配比 3:7,光周期 20L/4D,光强 150 μmol/(m2·s)]更有利于光合色素的积累。红蓝配比 3:7 的光照模式较其他处理更有利于蛋白质合成;处理 3[红蓝配比 7:3,光周期 20L/4D,光强 200 μmol/(m2·s)]有利于降低生长期叶用莴苣叶片硝态氮含量,促进可溶性糖的积累。综合分析得出 3 个光照因子对水培叶用莴苣生长及品质影响的重要程度依次为：光强、光质配比、光周期,最适的光照模式组合为：红蓝配比 7:3、光强 200 μmol/(m2·s)、光周期 20L/4D。本研究结果可为叶用莴苣生长的最适光环境提供参考,同时为 LED 灯具在植物照明领域的设计提供 技术支持。     

Growth,leaf photosynthesis and canopy light use efficiency under differing irradiance and soil N supplies in the forage grass Brachiaria decumbens Stapf

Irradiance and soil nitrogen effects on growth, net photosynthesis and radiation use efficiency (RUE) of Brachiaria decumbens were investigated in fertilized and non‐fertilized stands. Three levels of photosynthetic photon flux (PPF: S0 = 100%, S1 = 50% and S2 = 30%) and two N supplies, with (N+) and without (N?), were used. Forage biomass and nutrient accumulation, specific leaf area (SLA), leaf area index (LAI), fractional intercepted photosynthetic photon flux (fPPF), leaf photosynthetic response to light and efficiency of radiation use at leaf (A/Q) and canopy (RUE) levels were measured. Shade effects were mostly independent of soil N. Final yield was decreased by 34% (S1) and 57% (S2). Shade increased SLA (25–46%), so maximum LAI (2·4–3·3) was similar among light regimes. In N? stands, reductions in leaf biomass (14%), SLA (17%) and LAI (27%) were recorded, although forage yield was similar between soil N conditions. Under shade, peaks of A were comparable to those at full light, so A/Q was higher around midday. Derived parameters of the A‐PPF curves were similar between S0 and S2. A maximum fPPF = 0·8 (S0N+, S1N+) was recorded at LAI = 3–4. Under limited sunlight, relatively high RUE (1·6–2·8 g MJ^?1) were observed over both soil N conditions. We concluded that B. decumbens had a high plasticity to shade, thus explaining its success under silvopastoral systems.     

The Impact of Retail Light Source on Greening of Russet Burbank Potato Tubers

The use of accent lighting in retail stores has focused illumination on potatoes for greater consumer awareness. Unfortunately, this directed light on displayed potatoes may impact the rate or level of tuber greening. The objective of this study was to evaluate the influence of various retail accent light sources on greening and quality of illuminated tubers. Two separate experiments exposed ‘Russet Burbank’ potato tubers to fiber optic, ceramic metal halide, fluorescent, fluorescent with filter lighting (experiment 1) and fiber optic, halogen, and fluorescent lighting (experiment 2). In each experiment, tubers were exposed to a consistent light intensity (1390 lx in experiment 1 and 1300 lx in experiment 2) in addition to a dark control. Tubers were illuminated for 22 h per day at an ambient room temperature of 22 C. Six randomly selected tubers were evaluated for level of greening, chlorophyll concentration, and weight loss at day 0, 2, 4, 7, and 9. Total glycoalkaloid content was analyzed at days 0 and 9. In experiment 1, the fiber optic and fluorescent illuminated tubers showed significantly lower chlorophyll content compared to the ceramic metal halide light source. There was no significant difference in chlorophyll level or greening rating between the fluorescent light source and fluorescent with filter. In experiment 2, the fiber optic illuminated tubers had lower chlorophyll content and less visual greening compared to the halogen illuminated tubers. Total glycoalkaloids were not significantly impacted by light source. The use of fiber optic lighting or a combination of fiber optic lighting with standard fluorescent lighting would retard the progression of greening in the retail store yet potentially highlight the commodity for consumer eye-appeal.     

不同光质对紫苏光合特性的影响

以紫苏为材料,利用LED灯调制光源,按照光质组成的不同设置8个处理,测定紫苏叶片的光合与荧光参数,研究不同光质处理对紫苏光合特性的影响。结果表明:红蓝黄配比光(RBY)处理有利于提高紫苏叶片光合速率(P_n)、气孔导度(G_s)、蒸腾速率(T_r)、光合性能指标(PI_(ABS))、单位面积电子传递的量子产额(ET_O/CS)、PSⅡ最大光化学效率(ψ_(PO),即F_v/F_m)、电子传递到电子传递链中Q_A~-下游的其他电子受体的概率(ψ_O)和反应中心吸收的光能用于电子传递的量子产额(ψ_(EO)),说明RBY处理促进了紫苏PSII的活性,提升了光能利用率,而G和Y处理有减弱作用。不同光质处理下紫苏的光能利用率表现为红蓝黄配比光(RBY)红蓝配比光(RB)白光(CK)蓝光(B)红蓝绿配比光(RBG)红光(R)绿光(G)黄光(Y)。     

不同光质配比对大豆幼苗形态及光合生理参数的影响

室内模拟玉米/大豆套作下大豆冠层光质配比,设定白光（对照）、红光/蓝光=0.8和红/远红光=0.6三个处理,大豆品种选用贡选1号和桂夏3号,研究大豆幼苗形态及光合生理参数在不同光质配比下的变化特征。结果表明：红光/蓝光配比和红光/远红光配比处理与对照相比,大豆幼苗株高分别降低和增加,茎粗则相反。而根长、地上生物量、地下生物量及根冠比在红光/远红光配比处理下最低,与白光和红光/蓝光配比处理相比差异极显著（P<0.01）,但白光和红光/蓝光配比处理间差异不显著（P>0.01）。叶面积和叶绿素含量在红/远红光配比处理下分别最低和最高,而两大豆品种的净光合速率（Pn）、气孔导度（Gs）和PSII实际光化学量子产额（ΦPSⅡ）均在红光/蓝光处理下最高,而非光化学猝灭系数（NPQ）最低。两大豆品种的胞间CO2浓度（Ci）,蒸腾速率（Tr）, PSⅡ原初光能转化效率（Fv/Fm）,PSⅡ潜在活性（Fv/F0）在各处理间规律不明显。     

Effect of incandescent and fluorescent lighting used in photoperiod extension on the vegetative growth and floral development of four lines of pigeonpea

The effects of light quality, as used in photoperiod extension, on vegetative growth and floral development of pigeonpea [Cajanus cajan (L.) Millsp.] were studied using three photoperiod-insensitive lines, QPL2, Prabhat, and Hunt, and one photoperiod-sensitive line, Royes. Plants were grown in controlled-environment cabinets under day/night temperature regimes of 24/16°C (low) and 28/24°C (high) for 72 days after emergence (DAE). The five light treatments consisted of 12 and 16-h photoperiods and a 12-h photoperiod extended to 16 h with low-intensity lighting from either incandescent (I), fluorescent (F), or incandescent plus fluorescent (I+F) lamps.Little genetic variation occurred in vegetative response (main stem length and node number, leaf area and shoot dry weight) to extension light source. Response varied with temperature, plant age and growth stage. Main stem node appearance and stem extension tended to decline following floral initiation (FI), whereas leaf area and shoot dry weight accumulation increased rapidly after 35 or 42 DAE, irrespective of whether plants were vegetative or floral. Plants were larger under the high-temperature regime. Temperature altered plant response to extension light source. I-extension promoted growth under both temperature regimes, whilst I+F promoted growth under high temperatures but was unexpectedly inhibitory under low. Under high temperatures F extension was inhibitory prior to FI, but promoted later growth during floral bud development (FBD). Under low temperatures, F-extension was not inhibitory during the pre-initiation phase.The four genotypes differed in their floral response to extension light source, the effect on initiation and development of floral primordia varying dependent upon temperature. Low temperatures resulted in sensitivity to extension light source, delaying FI and FBD. In Royes, failure to initiate under low temperatures was associated with small plant size (≤3.5 g shoot dry weight). High temperatures tended to negate the delaying effects of extension light source, but resulted in photoperiod sensitivity, delaying FI in the early-flowering lines QPL-2 and Prabhat. Under high temperatures, Royes was insensitive (FI and FBD) to extensions containing incandescent light (I, I+F). Under high temperatures, time of flowering was least affected by incandescent extensions (I, I+F), and most by F-extension, which delayed FBD in all lines. Under low temperatures, I+F extensions resulted in the greatest variation in flowering time.It was concluded that where heterogeneity exists in floral response to the intensity and/or quality of light, use of artificial lighting to select for photoperiod sensitivity may lead to misclassification.     

不同比例红蓝LED灯对蔬菜育苗的补光效应

为解决华南地区冬春季节蔬菜育苗缺光现象,采用不同比例红蓝光组合的LED灯（红 ∶ 蓝=7 ∶ 3,7R3B;红 ∶ 蓝=8 ∶ 2,8R2B;红 ∶ 蓝=9 ∶ 1,9R1B）进行补光,以自然光为对照,探讨不同光质的LED灯补光对苦瓜、豆角、茄子和辣椒育苗的效应。结果表明：不同的红蓝光组合LED灯补光对苦瓜、豆角、茄子和辣椒育苗具有一定的促进作用,其中对苦瓜幼苗的鲜重、地下部分干物质积累、叶绿素含量以及根系活力具有显著的促进效应;对豆角幼苗地下部分干物质积累、叶绿素含量以及根系活力具有显著的促进效应;对辣椒和茄子的形态指标和生理指标均有显著的促进效应,辣椒育苗的最适壮苗光源为9R1B,茄子育苗的最适壮苗光源为8R2B。     

影响水稻叶片光合日变化因素的分析

 选择典型的干热天气,测定了盆栽水稻二九丰孕穗期的光合日变化及其影响因子,利用相关性分析和通径分析,考查了光强、叶温、胞间CO₂浓度、气孔导度、蒸腾速率和相对湿度对光合速率的影响。早晨8:30以前,光合速率的上升主要是光强造成的;光合速率在8:30达最大值,此后逐渐下降,其间光合速率的降低,尤其是“午睡”期间的下降,气孔因素是主要限制因子;下午14:30～18:00,光合速率与胞间CO₂浓度呈一定负相关,但未达显著水平,与光强、气孔导度、叶温和相对湿度有一定关系,相关系数达显著水平。     

不同LED光源对碧玉兰组培苗淀粉含量的影响

采用LED光源单色红光、蓝光、绿光及白光不同光质配比7种组合处理,以荧光灯为对照,研究其对野生碧玉兰组培苗叶片淀粉含量的影响。结果表明：在红蓝绿复合光(RBG)下,组培苗的淀粉含量最高,为9.977 8 mg/g,极显著高于荧光灯处理。在单色蓝光(B)下,组培苗的淀粉含量最低,为3.684 5 mg/g,极显著低于荧光灯(CK)和单色红光(R)处理,说明蓝光会明显抑制碧玉兰组培苗的淀粉合成。因此,在碧玉兰组培苗培育过程中,利用LED红蓝绿复合光源(RBG)取代传统的荧光灯光源是值得推荐的。     

Stomatal resistance of three potato cultivars as influenced by soil water status, humidity and irradiance

Summary Leaf stomatal resistance varies considerably in response to changes in environmental conditions. Understanding cultivar differences in the response of stomata to these conditions is important for effectively simulating water-use and growth. In this study the stomatal resistance of three field grown potato (Solanum tuberosum L.) cultivars Atlantic. Monona and Norchip was observed in response to photosynthetic photon flux density, leaf to air vapour pressure difference and root zone available soil water. Substantial variation in stomatal resistance was accounted for by functions of the environmental variables for both Monona and Norchip. The explained variation for Atlantic was considerably less. Light saturation occurred near 500 μmol m⁻² s⁻¹. Increasing stomatal resistance above 1000 μmol m⁻²s⁻¹ was also observed but is likely an artifact of stomatal closure on days in which mid-day leaf water potentials dropped below critical levels. Although the leaf presumably insufficient to obtain substantial effects. The soil water status was partially linked to the average 1000 h to 1500 h stomatal resistance on clear, sunny days. Significant differences were observed among the cultivars in the response of stomata to changes in the available soil water.     

石碌含笑光合及固碳特性

本文以石碌含笑二年生嫁接苗为研究对象,采用LI-6400便携式光合仪对其光合参数特征进行测定分析,并对其固碳释氧量进行估算,综合评价其适应性及生态效应。结果表明：石碌含笑的四季净光合速率（Pn）日变化并非呈现单一的双峰。1月、4月、7月的变化曲线为双峰型,10月为单峰型。石碌含笑不同月份Pn日均值由大到小依次为：10月>7月>4月>1月。其生长旺盛期在10月,石碌含笑在大气温度较低和光强较弱的秋季反而有更高的光合速率。石碌含笑的光补偿点低而光饱和点较高,说明能够适应不同的光照环境,在强光环境和弱光环境都有较强的光能利用能力。石碌含笑全年日均净固碳量为10.07 g/(m ²·d),拥有较强固碳能力。石碌含笑对强弱光均有较强的利用能力,在华南地区炎热气候条件下也具有“午休”的适应性自我调节机制,并且拥有较强的碳汇能力,兼具良好的景观效益与优良的生态效益,因此适合在华南地区推广种植。