不同光质LED光源对黄瓜幼苗光合参数、水分利用效率和叶绿体超微结构的影响   总被引：1，自引：0，他引：1  

曹刚  张帆  任静  马彦霞  张国斌  郁继华 《中国沙漠》2013,33(3):765-771

采用发光二极管（LED）为光源,以白光作对照,研究了红光、蓝光和红蓝组合光对黄瓜品种“银胚99”幼苗叶片光合参数及水分利用效率的影响,并观察了叶绿体超微结构的变化。结果表明,蓝光和红蓝组合光均显著提高了叶片的净光合作用,在处理到第10天时,蓝光提高幅度最大,较白光高出27.29%;在处理到第20天时,红蓝组合光8R/2B提高叶片光合速率幅度最大,较白光高出56.94%。红蓝组合光处理下叶片的后期净光合速率下降较小,水分利用效率提高显著。与白光相比,红光处理对叶片净光合速率的影响不存在差异,且在处理第20天时叶片净光合速率和水分利用效率与第10天相比,有明显下降。叶片叶绿体超微结构显示,不同光质对黄瓜幼苗叶绿体发育有显著影响;白光不利于叶片叶绿体的成熟,红光造成叶片叶绿体淀粉粒过分积累,抑制了光合产物从叶片中的输出;红蓝组合光8R/2B和7R/3B处理则有利于叶绿体基质、基粒片层的形成和同化产物的输出。  相似文献   

灌溉量对2种灌木光合特性和水分利用效率的影响     

郭自春  曾凡江  刘波  罗维成  宋聪  王会提  郭京衡 《中国沙漠》2014,34(2):448-455

采用野外试验,研究了灌溉量对新疆策勒绿洲木沙拐枣（Calligonum mongolicum）和花棒（Hedysarum scoparium）光合特性和水分利用效率的影响。结果表明：（1） 随着灌溉量的增加,沙拐枣和花棒的净光合速率均增加,但是蒸腾速率、气孔导度、胞间CO₂浓度没有明显增加;（2） 灌溉增加了沙拐枣的清晨水势和正午水势,并且只有灌溉和无灌溉处理的正午水势差异显著（p<0.05）;而灌溉只增加了花棒的清晨水势,并且只有充分灌溉和无灌溉的条件下差异显著（p<0.05）;（3） 在不同的灌溉条件下,沙拐枣和花棒的稳定碳同位素比率δ¹³C变化不大,沙拐枣在无灌溉、适度灌溉、充分灌溉下δ¹³C的平均值分别为-12.267、-12.147、-11.958,花棒的δ¹³C分别为-27.928、-28.068、-27.166;（4） 沙拐枣和花棒的水分利用效率均在无灌溉条件下明显高于灌溉条件下,而且一次性的灌溉不会改变其水分利用效率。  相似文献   

鄱阳湖南矶山湿地沉水植物活体的光合荧光特性     

简敏菲  汪斯琛  余厚平  李玲玉  简美锋  余冠军 《资源与生态学报(英文版)》2015,6(1):52-59

采用FluorCam便携式叶绿素荧光成像仪测定鄱阳湖南矶山国家级自然保护区白沙湖和常湖冬季沉水植物的光合荧光特性,包括QY-max（即Fv/Fm,PSⅡ的最大光量子产量）、ΦPSⅡ（PSⅡ实际量子效率）、qP（光化学淬灭系数）等参数及其相应的荧光成像;应用频度法统计估测沉水植物的频度,并测定水环境的营养水平。结果表明：白沙湖优势沉水植物黑藻（Hydrilla verticillata）和苦草（Vallisneria natans）的PSⅡ的最大量子产量分别为0.48-0.68和0.52-0.71,PSⅡ实际量子效率分别为0.32-0.58和0.20-0.46,表明白沙湖的黑藻和苦草具有相似的光合作用效率;而常湖优势沉水植物莕菜（Nymphoides peltatum）和苦草的PSⅡ最大光量子产量分别为0.66-0.77和0.19-0.68,PSⅡ实际量子效率分别为0.26-0.48和0.22-0.43,表明莕菜有较高的光合作用效率,容易形成优势物种。调查中发现,白沙湖黑藻的频度为90%,苦草为93.3%,小茨藻（Najas minor）为26.7%,眼子菜（Potamogeton franchetii）为10%;常湖中莕菜的频度为86.7%,苦草为16.7%,小茨藻为56.7%。白沙湖中沉水植物的频度值总体高于常湖,优势物种也存在差异性。综合分析白沙湖和常湖水体的营养水平、沉水植物多样性和光合荧光特性,结果表明：白沙湖的富营养化水平高于常湖,黑藻和苦草同为沉水植物中的优势种,光合活性相似;常湖中莕菜和苦草为优势种,但莕菜的光合活性显著高于苦草,这与湖泊水体透明度和南矶山湿地不同水体的富营养化差异及不同沉水植物的生态位有着密不可分的关系。  相似文献   

Effects of acidified seawater on calcification,photosynthetic efficiencies and the recovery processes from strong light exposure in the coral Stylophora pistillata          下载免费PDF全文

Takashi Nakamura  Akira Iguchi  Atsushi Suzuki  Kazuhiko Sakai  Yukihiro Nojiri 《Marine Ecology》2017,38(3)

The aim of this study was to investigate whether coral photosynthetic efficiencies and recovery processes are affected by CO₂‐driven ocean acidification in symbiont photosynthesis and coral calcification. We investigated the effects of five CO₂ partial pressure (pCO₂) levels in adjusted seawater ranging from 300 μatm (pre‐industrial) to 800 μatm (near‐future) and strong and weak light intensity on maximum photosynthetic efficiency and calcification of a branching coral, Stylophora pistillata, as this species has often been used in rearing experiments to investigate the effects of acidified seawater on calcification and photosynthetic algae of corals. We found that, the photosynthetic efficiencies and recovery patterns under different light conditions did not differ among pCO₂ treatments. Furthermore, calcification of S. pistillata was not affected by acidified seawater under weak or strong light conditions. Our results indicate that the photosynthetic efficiency and calcification of S. pistillata are insensitive to changes in ocean acidity.  相似文献   

MODIS大气产品的光合有效辐射估算研究   总被引：2，自引：0，他引：2  

陈卓奇  邵全琴  刘纪远  王军邦 《遥感学报》2012,16(1):25-37

利用气溶胶、水汽、云以及臭氧等MODIS标准大气产品,在简单辐射传输模型基础上估算青藏高原光合有效辐射,经验证估算的光合有效辐射与实测数据存在显著的线性相关,相关系数在0.8—0.9之间,最大误差为13%。经过敏感性分析发现云层厚度、气溶胶含量以及大气压力对光合有效辐射的影响大。臭氧和水汽含量的变化不敏感。云层厚度、Angstrom浑浊度系数和大气压力分别变化30%、25%和15%时,光合有效辐射变化分别为20%、5%和5%。  相似文献   

Photosynthesis versus irradiance relationships in the Atlantic sector of the Southern Ocean     

S Thomalla  E Kean  M Lucas  M-J Gibberd  R Barlow 《African Journal of Marine Science》2017,39(1):43-57

Eleven incubation experiments were conducted in the South Atlantic sector of the Southern Ocean to investigate the relationship between new production (ρNO^–₃), regenerated production (ρNH⁺₄), and total carbon production (ρC) as a function of varying light. The results show substantial variability in the photosynthesis–irradiance (P vs E) parameters, with phytoplankton communities at stations that were considered iron (Fe)-limited showing low maximum photosynthetic capacity (P^B_max) and low quantum efficiency of photosynthesis (α^B) for ρNO₃, but high P^B_max and α^B for ρNH₄, with consequently low export efficiency. Results at stations likely relieved of Fe stress (associated with shallow bathymetry and the marginal ice zone) showed the highest rates of P^B_max and α^B for ρNO₃ and ρC. To establish the key factors influencing the variability of the photosynthetic parameters, a principal components analysis was performed on P vs E parameters, using surface temperature, chlorophyll-a concentration, ambient nutrients, and an index for community size structure. Strong covariance between ambient nitrate (NO₃) and α^B for ρNO₃ suggests that Fe and possibly light co-limitation affects the ability of phytoplankton in the region to access the surplus NO₃ reservoir. However, the observed relationships between community structure and the P vs E parameters suggest superior performance by smaller-sized cells, in terms of resource acquisition and Fe limitation, as the probable driver of smaller-celled phytoplankton communities that have reduced photosynthetic efficiency and which require higher light intensities to saturate uptake. A noticeable absence in covariances between chlorophyll-a and α^B, between P^B_max and α^B, and between temperature and α^B may have important implications for primary-production models, although the absence of some expected relationships may be a consequence of the small dataset and low range of variability. However, significant relationships were observed between ambient NO₃ and α^B for ρNO₃, and between the light-saturation parameter E_k for ρNO₃ and the phytoplankton community’s size structure, which imply that Fe and light co-limitation drives access to the surplus NO₃ reservoir and that larger-celled communities are more efficient at fixing NO₃ in low light conditions. Although the mean P^B_max results for ρC were consistent with estimates of global production from satellite chlorophyll measurements, the range of variability was large. These results highlight the need for more-advanced primary-production models that take into account a diverse range of environmental and seasonal drivers of photosynthetic responses.  相似文献   

Simultaneous estimates ofsynechococcus spp. Growth and grazing mortality rates in the English Channel     

Ning Xiu-ren  Daniel Vaulot 《中国海洋湖沼学报》1996,14(1):8-16

The marine chroococooid phycoerythrin-containingSynechococcus spp. cyanobacterium has been implicated as a substantial component of the photosynthetic picoplankton in the ocean. Although its importance as food source for heterotrophic nanoplankton is now recognized, information about the cycling ofSynechococcus biomass and its diel pattern is limited and study methodology varies among authors. The selective metabolic inhibitor method was used to simultaneously estimate growth and grazing disappearance rates ofSynechococcus in the English Channel where growth rates ranged from 0.25 to 0.72/d (mean ±SD=0.51±0.17/d) and grazing mortality rates ranged from 0.19 to 0.64/d (mean ±SD=0.48±0.17/d). Size-fractionated experiments demonstrated that up to 70% ofSynechococcus disappearance could be attributed to grazers going through a 2 μm Nuclepore filter.Synechococcus grazing mortality rates (mean=0.74 ±0.25/d) during the day were always higher than that (mean=0.2±0.20/d) during the night, while growth rates showed no clear diel pattern. A positive correlation was observed between growth rates andin situ temperature ranging from 9 to 17°C, while in contrast grazing was independent of temperature. The close similatiry between average growth and grazing rates suggests a rapid recycling ofSynechococcus biomass in English Channel coastal waters.  相似文献   

STUDY ON PHOTOSYNTHETIC PARAMETERS AND PRIMARY PRODUCTION OF MARINE PHYTOPLANKTON IN MINNAN-TAIWAN SHOAL     

王宪  李文权 《中国海洋湖沼学报》1994,12(1):91-96

Carbon assimilation rates were determined in situ in the Minnan-Taiwan Shoal with the C-14 tracer method. Seasonal variations of photosynthetic parameters of marine phytoplankton were measured together with determination of Chl a and carbon content, Experimental results indicated that the average carbon-specific carbon accumulation rate is 0.85 d~(-1), mean primary productivity is 0.55 g C (m~2d)~(-1). Temperature effect on the growth of the algae can be described by the modle of Goldman and Carpenter. Supplementation of nutrients brought up by the upwelling in summer caused the observably higher primary productivities in autumn.  相似文献   

Effect of turbulence and inorganic carbon supply on growth ofDunaliella viridis Teodoresco     

Carlos Jiménez  Jesus Mercado  José Aguilera  J. M. rodriguez-Maroto  F. X. Niell 《International Journal of Salt Lake Research》1995,4(3):223-232

Turbulence is known to enhance growth in microalgae. We studied the possible effects of the extra inorganic carbon supplied to the cultures when air bubbling is the source of turbulence. A set of experiments was carried out to separate the effects of the subsidiary action of agitation on growth from those due to possible carbon enrichment from air CO₂ when air bubbling was the source of mixing. It was found that air bubbling does not induce an increase of the concentration of inorganic carbon in HCO ₃ ^– -enriched growth media, and that no differences appear between air-bubbled and CO₂-free air-bubbled cultures. On the other hand, photosynthetic O₂ was accumulated in the medium in non-mixed cultures, which showed higher respiration and lower photosynthetic rates, probably due to photoinhibition induced by oversaturation of O₂. Growth rate, maximal cell density and photosynthetic efficiency were higher in aerated cultures than in non-aerated ones.  相似文献   

干旱胁迫对甘草光合特性与生物量分配的影响   总被引：28，自引：13，他引：28  

刘长利  王文  崔俊茹  李帅英 《中国沙漠》2006,26(1):142-145

 为了探讨干旱胁迫对甘草光合特性与生物量分配的影响，采用土壤干旱胁迫处理盆栽2 a生甘草实生苗，测定胁迫30 d的甘草叶片净光合速率、蒸腾速率、气孔导度、胞间CO2浓度等生理指标和胁迫60 d的地上地下各器官生物量。结果显示，在土壤相对含水量为50％的轻度干旱胁迫下，甘草叶片光合生理指标与根生物量变化不显著，在土壤相对含水量为35％的严重干旱胁迫下，甘草叶片净光合速率与蒸腾速率显著下降，胞间CO2浓度显著升高，气孔导度显著降低，各器官生物量显著下降。但随着干旱胁迫程度的加剧，甘草水分利用效率与气孔限制值能够保持相对的稳定，生物量分配更多地流向地下器官，地上器官生物量分配明显变少，根冠比增大。研究表明，甘草的光合特性与生物量分配格局对于干旱环境具有很强的适应能力，引起甘草叶片光合速率下降的主要原因是非气孔因素。另外，在土壤相对含水量35％以上的干旱胁迫下，不但不会影响人工种植药材的产量，而且可能会促进甘草酸在根中的合成积累，提高药材质量。  相似文献