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春季西沙永乐龙洞浮游植物的昼夜垂直分布特征 预览
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作者 葛汝平 傅亮 +7 位作者 毕乃双 陈畅 刘光兴 庄昀筠 杨作升 范德江 姚鹏 陈洪举 《中国海洋大学学报:自然科学版》 CAS CSCD 北大核心 2020年第1期65-73,共9页
南海永乐龙洞位于西沙群岛永乐环礁,是迄今为止发现的最深的海洋蓝洞,水文环境及理化因素特殊,90 m以下水体为无氧环境。为研究永乐龙洞浮游植物的群落组成及其昼夜变化,于2017年3月在龙洞、潟湖及外礁坡进行浮游植物样品采集。研究结... 南海永乐龙洞位于西沙群岛永乐环礁,是迄今为止发现的最深的海洋蓝洞,水文环境及理化因素特殊,90 m以下水体为无氧环境。为研究永乐龙洞浮游植物的群落组成及其昼夜变化,于2017年3月在龙洞、潟湖及外礁坡进行浮游植物样品采集。研究结果表明:龙洞内叶绿素a浓度呈现随深度先增大后减小的趋势,日间浓度最大值层出现在40 m层(0.42μg/L),夜间则出现在20 m层(0.59μg/L)。永乐龙洞微微型浮游植物丰度介于1.1×10^3~5.1×10^4 cells/mL。聚球藻在上层水体占优势(0~20 m),40 m以下水层原绿球藻丰度对微微型浮游植物丰度贡献率最大(90%以上),微微型真核浮游植物丰度在整个水体都较低(除20 m层)。微微型浮游植物昼夜存在明显差异,夜间其丰度最大值层为20 m层,日间则上移至表层。本研究共记录微型和小型浮游植物5门41属55种(含未定种)。其中,硅藻门25属34种、甲藻门12属15种、金藻门1属1种、蓝藻3属、隐藻1属。微型和小型浮游植物丰度介于3.3×10^2~9.8×10^4 cells/L。甲藻丰度对浮游植物总丰度贡献率最大,其次是硅藻,隐藻和蓝藻丰度仅在少数水层占优势。微型和小型浮游植物昼夜变化明显,夜间丰度最大值层为20 m层,日间则出现在40 m层。微微型、微型和小型浮游植物垂直分布与叶绿素a浓度垂直分布一致性高。龙洞浮游植物的种类数和丰度高于潟湖和外礁坡。 展开更多
关键词 永乐龙洞 南海 叶绿素A 微微型浮游植物 微型和小型浮游植物 垂直分布 昼夜变化
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大气氮沉降对南黄海初级生产过程影响的数值研究 预览
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作者 郭伟 史洁 +1 位作者 朱君莹 赵亮 《中国海洋大学学报:自然科学版》 CAS CSCD 北大核心 2020年第1期115-125,共11页
本研究利用三维物理-生物耦合模型模拟了大气氮沉降对南黄海主要初级生产过程的影响,并通过数值实验区分了不同季节大气氮沉降的贡献。模拟结果显示,大气氮沉降明显增大了南黄海表层溶解无机氮的浓度,近岸海域增加量较大,可以达到3.0 mm... 本研究利用三维物理-生物耦合模型模拟了大气氮沉降对南黄海主要初级生产过程的影响,并通过数值实验区分了不同季节大气氮沉降的贡献。模拟结果显示,大气氮沉降明显增大了南黄海表层溶解无机氮的浓度,近岸海域增加量较大,可以达到3.0 mmol/m^3,且由近岸海域到黄海中部海域有明显的递减趋势,这主要是由于近岸海域无机氮来源众多,导致浓度较高,大气沉降的氮不会被浮游植物生长吸收,出现氮累积。大气氮沉降明显促进了黄海中部春季表层水华和夏季次表层叶绿素最大值两个重要初级生产过程,春季表层叶绿素增加量最大,可达0.20 mg/m^3,夏季次表层叶绿素浓度增加最显著,可达0.10 mg/m^3,分别约为峰值浓度的10%和6%。不同季节大气氮沉降对初级生产过程的贡献不同,冬季氮沉降可以存留下来影响春季水华过程,但作用小于春季氮沉降;夏季,由于水体层化较强,本季的氮沉降对次表层叶绿素最大值的促进作用并不明显,反而冬季氮沉降的影响大于春季和夏季的氮沉降。同时,大气氮沉降也促进了氮循环的各个过程,包括浮游植物生长吸收、呼吸释放和矿化过程。 展开更多
关键词 大气氮沉降 南黄海 溶解无机氮 叶绿素 初级生产过程
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基于计算机视觉的水稻叶绿素含量测定 预览
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作者 吴少俊 《农机化研究》 北大核心 2020年第4期223-226,共4页
叶绿素含量影响植物的各种生理机能,准确测定水稻叶绿素含量有利于了解水稻的光合作用能力,为高产育种和栽培提供依据。叶绿素含量的测定方法有多种,传统测定方法步骤繁琐且耗时费力,而便携式叶绿素仪只能进行点测定。计算机视觉是一种... 叶绿素含量影响植物的各种生理机能,准确测定水稻叶绿素含量有利于了解水稻的光合作用能力,为高产育种和栽培提供依据。叶绿素含量的测定方法有多种,传统测定方法步骤繁琐且耗时费力,而便携式叶绿素仪只能进行点测定。计算机视觉是一种快速便捷的图像处理技术,可以用于作物的色素含量测定和营养状况诊断。为此,设计了一种基于计算机视觉的水稻叶绿素含量测定方法,叶片图像通过扫描获得,经过处理并提取叶片轮廓后以G-R、B-R和R/(G+B)等3个颜色特征参数建立叶绿素含量的估算模型。结果表明:以G-R和R/(G+B)建立的模型精度较高,对检验样本SPAD值拟合方程的决定系数和斜率都接近1,可以用来准确测定水稻的叶绿素含量。 展开更多
关键词 水稻 叶绿素 计算机视觉
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Study on the Applicability of Landsat-8 Images as a Tool for Monitoring the Trophic State of Lake Guiers (Senegal) 预览
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作者 Charles Diédhiou Seybatou Diop +2 位作者 Gayane Faye Tijani Moshod Souléye Wade 《水资源与保护(英文)》 2019年第4期434-447,共14页
In this study, an algorithm to transform LANDSAT 8 images of Lake Guiers into chlorophyll-a concentration maps was developed. The objective was to see the feasibility of this method as a mapping tool for monitoring th... In this study, an algorithm to transform LANDSAT 8 images of Lake Guiers into chlorophyll-a concentration maps was developed. The objective was to see the feasibility of this method as a mapping tool for monitoring the trophic state of the Lake. The available data are 15 in-situ measurements of the CHL-a content of Lake Guiers’ water using a Micro FLU device and images of the lake acquired in 2013 and 2016 by the LANSAT 8 OLI sensor. A series of correlation tests (simple linear functions, multi-variables, or containing two- order terms) were performed between the spectral sensor signal of June 19, 2016 LANSAT 8 image (“corrected” and converted into reflectance) and the CHL-a content of Lake waters measured on the same day of the satellite record. This was, to find the best regression equation that can be inferred to develop an algorithm to transform LANDSAT 8 image into CHL-a concentration maps. The best equation obtained by correlating the ground truths and the reflectance ratios of the visible and near infrared bands (B2, B3, B4 and B5), is as follows: where B2 = Blue band, B3 = Green band, B4 = Red band, B5 = NIR band. The obtained R2 is 0.703 (e.g., a correlation coefficientof 0.84), revealed that the measured concentrations are well reproduced by the regression model. Applying this model to the 2013 and 2016 image data revealed the monthly variations of the lake CHL-a contents and their seasonal evolution and interannual variations. The obtained results are quite consistent with those from similar studies and provide valuable information regarding Lake Guiers’ vulnerability to algal development. The calculation and analysis of the variability of the CHL-a contents over the study period made it possible to evaluate the trophic state of the Lake, which shows a general tendency for eutrophication process, leading to a progressive degradation of the quality of the water resource. 展开更多
关键词 LAKE Guiers LANDSAT 8 CHLOROPHYLL a TROPHIC State
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毛竹茎秆发育过程中不同节间叶绿素荧光的变化 预览
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作者 王柯杨 卜柯丽 +5 位作者 马元丹 栗青丽 王灵杰 高岩 高海波 张汝民 《浙江农林大学学报》 CAS CSCD 北大核心 2019年第4期697-703,共7页
为了揭示毛竹Phyllostachys edulis快速生长期茎秆不同节间叶绿素荧光特征,以毛竹笋竹茎秆为材料,用YZQ-500型非调制式叶绿素荧光仪和JIP-test数据分析方法,研究了茎秆不同节间光合色素质量分数和叶绿素荧光参数的变化特征。结果显示:... 为了揭示毛竹Phyllostachys edulis快速生长期茎秆不同节间叶绿素荧光特征,以毛竹笋竹茎秆为材料,用YZQ-500型非调制式叶绿素荧光仪和JIP-test数据分析方法,研究了茎秆不同节间光合色素质量分数和叶绿素荧光参数的变化特征。结果显示:随着节间的升高,毛竹笋竹茎秆中叶绿素a,叶绿素b和类胡萝卜素质量分数显著下降(P<0.05);单位面积捕获的光能(TRo/CSo),单位面积电子传递的量子产额(ETo/CSo),PSⅡ反应中心吸收光能用于电子传递的量子产额(φEo),PSⅡ最大光化学效率(φPo),光合性能指数(PIABS)和反应中心数量(RC/CSo)显著下降(P<0.05);用于热耗散的量子比率(φDo),单位面积热耗散(DIo/CSo)和单位反应中心耗散掉的能量(DIo/RC)显著上升(P<0.05),表明茎秆上下部节间的生长发育存在明显差异,中下部节间PSⅡ反应中心活性较强,光能转换效率较高,能量耗散较少,生长较快;上部节间光合功能相对较弱,生长比较缓慢。研究成果对明确毛竹快速生长机制具有参考价值。 展开更多
关键词 植物学 毛竹 茎秆 节间 叶绿素 叶绿素荧光
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金边杂种胡颓子叶色突变体叶色变化机理的初步研究 预览
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作者 陈红 吴昌琦 +5 位作者 高若诚 刘志强 李云龙 王传永 李丹丹 陆小清 《江苏林业科技》 2019年第4期49-53,共5页
以野生型杂种胡颓子(WT)和突变型金边杂种胡颓子(MT)的3年生扦插苗为供试材料,研究突变型金边杂种胡颓子叶绿素含量与光合特性等生理指标,分析叶色变化的原因。结果显示:(1)叶绿素总含量:杂种胡颓子(WT1.530mg/g)>金边杂种胡颓子叶... 以野生型杂种胡颓子(WT)和突变型金边杂种胡颓子(MT)的3年生扦插苗为供试材料,研究突变型金边杂种胡颓子叶绿素含量与光合特性等生理指标,分析叶色变化的原因。结果显示:(1)叶绿素总含量:杂种胡颓子(WT1.530mg/g)>金边杂种胡颓子叶片绿色部位(MT-绿色1.078mg/g)>金边杂种胡颓子叶片黄色部位(MT-黄化0.031mg/g);类胡萝卜素含量:WT(0.505mg/g)>MT-绿色(0.318mg/g)>MT-黄化(0.050mg/g);(2)金边杂种胡颓子叶片绿色部位的Chla/b比值较WT叶片绿色部位,没有显著性的差异,但其叶片黄化部位的Chla/b比值显著低于野生型杂种胡颓子;(3)金边杂种胡颓子较野生型胡颓子光合速率及相关参数都有显著的改变。可见,金边杂种胡颓子的叶色变化是由叶片色素含量变化导致,导致植株的光合参数与叶绿素荧光参数等指标发生改变。 展开更多
关键词 胡颓子 叶绿素 叶色 光合速率 叶绿素荧光参数
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Effect of low-nitrogen stress on photosynthesis and chlorophyll fluorescence characteristics of maize cultivars with different lownitrogen tolerances 预览
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作者 WU Ya-wei LI Qiang +6 位作者 JIN Rong CHEN Wei LIU Xiao-lin KONG Fan-lei KE Yong-pei SHI Haichun YUAN Ji-chao 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第6期1246-1256,共11页
Nitrogen(N)is a critical element for plant growth and productivity that influences photosynthesis and chlorophyll fluorescence.We investigated the effect of low-N stress on leaf photosynthesis and chlorophyll fluoresc... Nitrogen(N)is a critical element for plant growth and productivity that influences photosynthesis and chlorophyll fluorescence.We investigated the effect of low-N stress on leaf photosynthesis and chlorophyll fluorescence characteristics of maize cultivars with difference in tolerance to low N levels.The low-N tolerant cultivar ZH311 and low-N sensitive cultivar XY508 were used as the test materials.A field experiment(with three N levels:N0,0 kg ha–1;N1,150 kg ha–1;N2,300 kg ha–1)in Jiyanyang,Sichuan Province,China,and a hydroponic experiment(with two N levels:CK,4 mmol L–1;LN,0.04 mmol L–1)in Chengdu,Sichuan Province,China were conducted.Low-N stress significantly decreased chlorophyll content and rapid light response curves of the maximum fluorescence under light(Fm′),fluorescence instable state(Fs),non-photochemical quenching(qN),the maximum efficiency of PSII photochemistry under dark-adaption(Fv/Fm),potential activity of PSII(Fv/Fo),and actual photochemical efficiency of PSII(ΦPSII)of leaves.Further,it increased the chlorophyll(Chl)a/Chl b values and so on.The light compensation point of ZH311 decreased,while that of XY508 increased.The degree of variation of these indices in low-N tolerant cultivars was lower than that in low-N sensitive cultivars,especially at the seedling stage.Maize could increase Chl a/Chl b,apparent quantum yield and light saturation point to adapt to N stress.Compared to low-N sensitive cultivars,low-N tolerant cultivars maintained a higher net photosynthetic rate and electron transport rate to maintain stronger PSII activity,which further promoted the ability to harvest and transfer light.This might be a photosynthetic mechanism by which low-N tolerant cultivar adapt to low-N stress. 展开更多
关键词 MAIZE NITROGEN CHLOROPHYLL content PHOTOSYNTHESIS CHLOROPHYLL FLUORESCENCE characteristics
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Genetic Nature of the “Hanthoviresens” Mutation of l - 4 Yellow Line—Transforming into Green and Their Relationship with the Chlorophylls Content 预览
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作者 Yahyo Bakhodirovich Tursunov Miradham Fuzailovich Abzalov 《美国植物学期刊(英文)》 2019年第11期2047-2051,共5页
It was determined that the yellow colour of Hanthoviresens mutation in L4 line of leaves is the result of genetic transforming into green and correlation of their hybrids on the L3. The yellow color in the leaves of L... It was determined that the yellow colour of Hanthoviresens mutation in L4 line of leaves is the result of genetic transforming into green and correlation of their hybrids on the L3. The yellow color in the leaves of L4 line is the result of recessive mutation relatively to anthocyanin colour in L3 line. This mutation and chlorophylls quantity in L4 line are being controlled by nuclear genes and high quantity of chlorophylls in L3 line is the result of linkage in gene group where gene Rstv is located or the result of the effect of pleiotropia on chlorophylls content. That is why chlorophylls quantity in plants with yellow colour is lower than in L3 line as these plants resulted from expression of rprprst<sup style="margin-left:-6px;">v rst<sup style="margin-left:-6px;">v gene type. 展开更多
关键词 CHLOROPHYLL Experimental PHENOTYPE ONTOGENESIS
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Growth and Photosynthetic Pigments of Cotton Cultivars Irrigated with Saline Water 预览
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作者 Elka Costa Santos Nascimento Ronaldo do Nascimento +5 位作者 André Alisson Rodrigues da Silva Carlos Vailan de Castro Bezerra Mateus Costa Batista Luana Lucas de Sá Almeida Veloso Márcia Cristina de Araújo Pereira Hallyson Oliveira 《农业科学(英文)》 2019年第1期81-91,共11页
The cultivation of cotton is a relevant socioeconomic activity in the Brazilian agricultural scenario. In the Brazilian Northeast, however, production is limited by low rainfall, requiring water supplementation, a pro... The cultivation of cotton is a relevant socioeconomic activity in the Brazilian agricultural scenario. In the Brazilian Northeast, however, production is limited by low rainfall, requiring water supplementation, a problem for the cotton cultivation practiced in the semi-arid region, due to the presence of saline ions in several water sources, from where the water is used for irrigation. It is necessary to identify cultivars that better tolerate saline stress in order to provide subsidies for their cultivation under such conditions. In this sense, the objective was to evaluate the tolerance of cotton cultivars to salinity. The experiment was conducted in a greenhouse, belonging to the Natural Resource Technology Center of the Federal University of Campina Grande, Campus I, Campina Grande, Brazil, in a completely randomized design in a 2 × 5 factorial scheme, with four replications, totaling 40 experimental units (BRS 368 RF and BRS SAFIRA) submitted to five saline levels (1.5, 3.0, 4.5, 6.0 and 7.5 dS·mˉ1). Irrigation with water saline of EC from 1.5 dS·mˉ1 affects adversely the growth of cotton cultivars, causing reductions in plant height, stem diameter, leaf area and number of leaves. Saline stress reduced the levels of the photosynthetic pigments of the cotton plants studied. 展开更多
关键词 GOSSYPIUM hirsutum L. SALINITY CHLOROPHYLL
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Eastern Oyster (<i>Crassostrea virginica</i>) Filtration Efficiency of Chlorophyll-<i>a</i>under Dynamic Conditions in the Hudson-Raritan Estuary at Pier 40, New York City 预览
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作者 Jane E. Perrino Dennis R. Ruez Jr. 《生态学期刊(英文)》 2019年第7期238-271,共34页
Eastern oyster (Crassostrea virginica) abundance has declined severely over the past century along the Atlantic and Gulf coasts of the United States. For varied reasons, overfishing among the foremost, bivalves no lon... Eastern oyster (Crassostrea virginica) abundance has declined severely over the past century along the Atlantic and Gulf coasts of the United States. For varied reasons, overfishing among the foremost, bivalves no longer make up considerable reefs as was common. While discourse continues on oyster restoration and augmentation, gaps in knowledge of C. virginica and regional environmental interactions remain. Our primary aim was to examine the C. virginica filter feeding of phytoplankton in the Hudson River Estuary, New York City. Secondarily, this study examined the filtration of these oysters in relation to environmental attributes. Chlorophyll-a, the predominant photosynthesizing pigment in red and green algae, is an indicator of phytoplankton productivity in aquatic settings. Crassostrea virginica consumes first-tier plankton from the water column’s seston;thus analysis of chlorophyll-a content allows estimating phytoplankton concentrations, from which oyster filtration efficiency (FE) was quantified. Water conditions (temperature, dissolved oxygen, pH, salinity, turbidity, tide and flow rate) also were recorded. Spectrophotometric determination of chlorophyll-a concentration methodology was derived from the Standard Methods text favored by the US EPA. This project compared real-time Hudson River Estuary (HRE) water samples prior to passing through a contained oyster reef and samples of water post-filtration. This sampling scenario was unique as the contained reef used was fed by HRE water. Most studies on oyster filtration have been laboratory-based, and few assessed oysters in the field. This study took place at Pier 40, the River Project Wetlab, lower Hudson River along Manhattan. The FE of this reef was calculated for two months during various environmental states which can be the basis of future investigations. Statistically significant differences were found between pre- and post-filtration water samples (Z = 4.620, p < 0.001). This study provides a glimpse at how the oysters fare in the HRE environment 展开更多
关键词 CHLOROPHYLL-A CRASSOSTREA virginica Filtration Efficiency HUDSON River
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Data Mining of Spatio-Temporal Variability of Chlorophyll-a Concentrations in a Portion of the Western Atlantic with Low Performance Hardware 预览
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作者 Italo F. Di Paolo Nelson A. Gouveia +3 位作者 Luiz C. Ferreira Neto Eduardo T. Paes Nandamudi L. Vijaykumar ádamo L. Santana 《软件工程与应用(英文)》 2019年第5期149-170,共22页
The contemporary scientific literature that deals with the dynamics of marine chlorophyll-a concentration is already customarily employing data mining techniques in small geographic areas or regional samples. However,... The contemporary scientific literature that deals with the dynamics of marine chlorophyll-a concentration is already customarily employing data mining techniques in small geographic areas or regional samples. However, there is little focus on the issue of missing data related to chlorophyll-a concentration estimated by remote sensors. Intending to provide greater scope to the identification of the spatiotemporal distribution patterns of marine chlorophyll-a concentrations, and to improve the reliability of results, this study presents a data mining approach to cluster similar chlorophyll-a concentration behaviors while implementing an iterative spatiotemporal interpolation technique for missing data inference. Although some dynamic behaviors of said concentrations in specific areas are already known by specialists, systematic studies in large geographical areas are still scarce due to the computational complexity involved. For this reason, this study analyzed 18 years of NASA satellite observations in one portion of the Western Atlantic Ocean, totaling more than 60 million records. Additionally, performance tests were carried out in low-cost computer systems to check the accessibility of the proposal implemented for use in computational structures of different sizes. The approach was able to identify patterns with high spatial resolution, accuracy and reliability, rendered in low-cost computers even with large volumes of data, generating new and consistent patterns of spatiotemporal variability. Thus, it opens up new possibilities for data mining research on a global scale in this field of application. 展开更多
关键词 DATA Mining Clustering CHLOROPHYLL ATLANTIC MISSING DATA Small HARDWARE
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黄花柳3个无性系叶色及叶绿素荧光特性比较 预览
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作者 王晓叶 王力源 +3 位作者 刘兴菊 贾泽云 杨春弟 梁海永 《安徽农业科学》 CAS 2019年第9期118-121,共4页
[目的]了解黄花柳资源的变异特性。[方法]以黄花柳3个无性系为材料,通过柯尼卡CR-400全自动色差计对其叶色参数进行测定,通过乙醇提取方法对其叶绿素含量进行测定,使用PocketPEA快速荧光仪对其叶绿素荧光特性进行分析比较。[结果]叶绿... [目的]了解黄花柳资源的变异特性。[方法]以黄花柳3个无性系为材料,通过柯尼卡CR-400全自动色差计对其叶色参数进行测定,通过乙醇提取方法对其叶绿素含量进行测定,使用PocketPEA快速荧光仪对其叶绿素荧光特性进行分析比较。[结果]叶绿素含量与L、a均呈显著负相关;金枝黄花柳的叶色偏黄、叶绿素含量较低,但其潜在光化学活性最强,对强光胁迫具有较强的自我保护能力;普通黄花柳叶色偏绿、叶绿素含量较高,其潜在光化学活性也较强,但其对光能的利用率最低;红枝黄花柳的叶色较金枝黄花柳偏绿,较普通黄花柳偏黄,其叶绿素含量与光能利用率均介于二者之间。[结论]叶绿素含量越高叶片颜色越偏绿色且越明亮;金枝黄柳较其他2个黄花柳无性系叶片颜色更鲜艳,且其光化学活性最强,对光能的利用率最大。 展开更多
关键词 黄花柳 叶色参数 叶绿素 叶绿素荧光特性
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Phytoplankton Productivity and Hydrology in an Impacted Estuarine Complex in Northeastern Brazil 预览
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作者 Laisa Madureira da Silva Fernando Ant?nio do Nascimento Feitosa +3 位作者 Manuel de Jesus Flores Montes Amanda Yumi Otsuka Flávia Saldanha-Corrêa Carlos Noriega 《生态学期刊(英文)》 2019年第10期458-477,共20页
The aim of the current study was to evaluate the productive capacity of the phytoplankton community and other environmental variables in the estuarine area of Suape;while considering the constant morphological, sedime... The aim of the current study was to evaluate the productive capacity of the phytoplankton community and other environmental variables in the estuarine area of Suape;while considering the constant morphological, sedimentological and hydrological changes, the site has been facing due to the implementation and expansion of an industrial and port complex. The study comprised 6 campaigns: 3 in the dry season and 3 in the rainy season. Water samples were collected from the surface layer of the internal and external portions of the estuarine bay during low spring tides. The salinity ranged from 32.20 to 37.10, the water temperature ranged from 26.60°C to 29.40°C, and the oxygen saturation rate ranged from 58.5% to 114.5%. There was significant seasonal variation. The nitrite concentration was higher during the rainy season, whereas the ammonia concentration was higher during the dry season;the higher ammonia concentration helped increase chlorophyll-a levels and rates of primary productivity, which ranged from 0.02 - 2.45 mg·m&#8722;3 and from 0.34 to 4.32 mg·C·m&#8722;3·h&#8722;1, respectively. Chlorophyll-a a-containing biomass, and this reflected the low nutrient content in the water and indicated that the area was free from eutrophication processes. The decrease of rainfall during the sampling months and the anthropogenic changes in the environment led to reduced continental contributions, increased marine interference, nutrient dilution and loss of phytoplankton production capacity in Suape Bay, which severely damaged other trophic links in the ecosystem. 展开更多
关键词 ESTUARINE Area PHYTOPLANKTON Primary PRODUCTIVITY CHLOROPHYLL a Suape Bay
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盐胁迫对多花水仙部分生理特性和叶绿素荧光参数的影响 预览
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作者 李全超 刘洋 +3 位作者 肖瑶宇 李琳 胡邵彬 陈晓静 《福建农林大学学报:自然科学版》 CSCD 北大核心 2019年第2期161-167,共7页
以'云香'、'黄花2号'、白花Ⅰ号和白花Ⅱ号4种多花水仙为材料,测定盐胁迫(NaCl浓度分别为 0、50、100、150、200和250 mmol·L^-1)7 d后水仙叶片叶绿素含量、丙二醛(MDA)含量、过氧化物酶(POD)活性及叶绿素荧光参... 以'云香'、'黄花2号'、白花Ⅰ号和白花Ⅱ号4种多花水仙为材料,测定盐胁迫(NaCl浓度分别为 0、50、100、150、200和250 mmol·L^-1)7 d后水仙叶片叶绿素含量、丙二醛(MDA)含量、过氧化物酶(POD)活性及叶绿素荧光参数的变化,研究多花水仙的耐盐性.结果表明,盐胁迫下,4种水仙叶片的叶绿素含量均有所下降,当NaCl浓度增大到100 mmol·L^-1时,白花Ⅰ号和白花Ⅱ号的叶绿素含量比'云香'和'黄花2号'下降得更为显著. MDA含量随着盐浓度的增大而上升,白花Ⅰ号和白花Ⅱ号的MDA含量明显高于'云香'和'黄花2号'.POD活性随着盐浓度的增大整体有所上升,但'云香'的POD活性呈先上升后下降的趋势.盐胁迫下,4种水仙的最大荧光产量(Fm)、潜在光化学效率(Fv/Fo)、最大光化学效率(Fv/Fm)、有效光化学效率(Fv'/Fm')和光化学猝灭系数(qP)下降,初始荧光产量(Fo)上升;随着盐浓度的增大,白花Ⅰ号和白花Ⅱ号各种叶绿素荧光参数的变化比'云香'和'黄花2号'更加显著.总之,随着盐浓度的增大,4种水仙叶片叶绿素荧光参数的变化幅度明显小于叶绿素含量、MDA含量和POD活性的变化,表明短期盐胁迫对4种水仙造成一定程度的损伤,但没有对光系统造成不可逆的破坏,说明水仙具备一定的抗盐性. 展开更多
关键词 多花水仙 盐胁迫 叶绿素含量 过氧化物酶活性 丙二醛含量 叶绿素荧光参数
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Free-Living Nematodes as Pollution Indicator in Incomati River Estuary, Mozambique 预览
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作者 Mthobisi Innocent Soko Thomas Kwadwo Gyedu-Ababio 《生态学期刊(英文)》 2019年第5期117-133,共17页
Four sites following the salinity gradient of the Incomati River Estuary E1 (0-3NST), E2 (3-5NST), E3 (6-18NST) and E4 (19-27NST) were selected for the study. The aim of the study was to use free-living marine nematod... Four sites following the salinity gradient of the Incomati River Estuary E1 (0-3NST), E2 (3-5NST), E3 (6-18NST) and E4 (19-27NST) were selected for the study. The aim of the study was to use free-living marine nematodes as pollution indicators in an area strongly affected by anthropogenic activities. Multivariate statistical analyses were used to determine the relationship between different environmental factors and with free-living marine nematodes. Metals such Cadmium, Colbat, Chromium, Copper, Iron, Manganese, Nickel, Vadium, Zinc and Aluminium influenced the diversity and density of free-living nematodes. Shannon-Wiener Diversity, Maturity Index and colonize-persisters percentage (c% - p%) were found to be good tools for use as pollution indicators in the study. Nematode genera such as Terschellingia, Theristus and Halalaimus were found to be dominant at a site strongly impacted by both metals concentration and organic matters. The three genera are believed to be good indicators of pollution in the Incomati River Estuary. It is recommended that further studies are done along the Mozambican Coast to identify nematodes that can be used as pollution indicators. 展开更多
关键词 ESTUARY Nematodes CHLOROPHYLL-A Metals ORGANIC MATTER POLLUTION
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Remote Sensing Applied to the Evaluation of Spatial and Temporal Variation of Water Quality in a Coastal Environment, Southeast Brazil 预览
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作者 Pedro Bettencourt Julio Cesar Wasserman +5 位作者 Fábio Ferreira Dias Paulo Roberto Alves Dandara Bernardino Bezerra Camila Américo Santos Luis Perez Zotes Sérgio Ricardo Barros 《地理信息系统(英文)》 2019年第5期500-521,共22页
The monitoring of water quality in large coastal regions demands great analytical efforts through the collection of many samples, over long periods. Remote sensing is a reliable tool that can provide valuable informat... The monitoring of water quality in large coastal regions demands great analytical efforts through the collection of many samples, over long periods. Remote sensing is a reliable tool that can provide valuable information on the spatial and temporal variations of environmental parameters, particularly turbidity and chlorophyll a. The aim of the present research was to evaluate the spatial and temporal distribution of water quality from 2005 to 2017 along the north coast of S&#227;o Paulo and its responses to the implementation of industrial developments and to variations in rainfall. Fifty-two MODIS images were used, showing concentrations of chlorophyll a and turbidity, in the dry season and wet season, from 2005 to 2017. The results showed that dilution processes (due to rainfall) control chlorophyll a concentrations. However, a notable increase in concentrations could be identified after the installation of some of the developments in the region, particularly roads and ports. Turbidity was also shown to be affected by dilution processes, and during the wet season this parameter presented lower values. No effect in the results of turbidity could be identified from the installation of roads or ports, showing that vegetation cover exerts an important control on the erosional processes. 展开更多
关键词 Water Quality CHLOROPHYLL a TURBIDITY MODIS REMOTE SENSING
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高效提取3种不同类型植物叶片色素的方法 预览
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作者 周武先 段媛媛 +3 位作者 卢超 艾伦强 何银生 张美德 《西北农业学报》 CAS CSCD 北大核心 2019年第1期97-104,共8页
旨在探索不同提取方式对不同类型叶片色素的提取效果。以中华蚊母树、栀子树和油麦菜的叶片作为3种不同类型的试验材料,分析溶剂、温度、时间、光照强度及叶片与溶剂的质量体积比对3种不同类型叶片色素提取效率的影响。结果表明,浸提时... 旨在探索不同提取方式对不同类型叶片色素的提取效果。以中华蚊母树、栀子树和油麦菜的叶片作为3种不同类型的试验材料,分析溶剂、温度、时间、光照强度及叶片与溶剂的质量体积比对3种不同类型叶片色素提取效率的影响。结果表明,浸提时间、温度和光照强度等因素均会不同程度地影响叶片组织中色素的提取。不同类型叶片色素的提取均以液氮法(MLN)提取效率最高。该法对油麦菜叶片色素的提取可完全避免光照,减少色素降解,色素提取时间缩短至5 min;对中华蚊母树和栀子树叶片,研磨提取的时间较短且更加充分,色素提取效率高,整个提取过程不超过10 min。MLN操作简便、耗时短、效率高、测定结果稳定,可用于科研工作和工业生产中对植物叶片组织色素的快速提取与精确测定。 展开更多
关键词 叶绿素A 叶绿素B 类胡萝卜素 高效 快速测定
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低温胁迫对玉米转绿过程中叶绿素生物合成的影响 预览
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作者 毛晶晶 李泽娇 +2 位作者 赵雨晴 袁澍 袁明 《四川农业大学学报》 CSCD 北大核心 2019年第5期617-622,共6页
【目的】通过对低温胁迫下玉米(Zea mays L.)幼苗转绿过程中叶绿素生物合成中间产物的分析,探究转绿过程中低温调控叶绿素合成的机制。【方法】将黑暗下发芽6 d的玉米幼苗分别置于25℃常温和14℃低温条件下见光48 h,测定见光前和不同温... 【目的】通过对低温胁迫下玉米(Zea mays L.)幼苗转绿过程中叶绿素生物合成中间产物的分析,探究转绿过程中低温调控叶绿素合成的机制。【方法】将黑暗下发芽6 d的玉米幼苗分别置于25℃常温和14℃低温条件下见光48 h,测定见光前和不同温度下见光后幼苗的叶绿素生物合成的主要前体物质积累量,以分析低温对叶绿素生物合成途径的影响。【结果】在25℃常温下,光照促进叶绿素(Chl)和血红素(heme)的合成;而在14℃低温胁迫下,δ-氨基乙酰丙酸(ALA)和Mg-原卟啉Ⅸ(Mg-ProtoⅨ)的积累量显著上升,单卟啉胆色素原(PBG)、尿卟啉原Ⅲ(UrogenⅢ)、粪卟啉原Ⅲ(CoprogenⅢ)、原卟啉Ⅸ(ProtoⅨ)、Mg-原卟啉甲酯(Mpe)、Mg-原卟啉Ⅸ二酯(Mpde)、原叶绿素酸酯(Pchlide)和叶绿素酸酯(Chlide)光照后积累量较常温下低,最终导致叶绿素含量下降,表明ALA向PBG的转化、及Mg-ProtoⅨ向Mpe的转化过程可能受到低温抑制。【结论】14℃低温通过影响ALA向PBG的转化以及Mg-ProtoⅨ向Mpe的转化,抑制玉米的转绿过程。 展开更多
关键词 玉米 叶绿素 前体物质 低温胁迫 生物合成
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Early selection of bread wheat genotypes using morphological and photosynthetic attributes conferring drought tolerance 预览
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作者 Hafiz Ghulam Muhu-Din Ahmed Abdus Salam khan +2 位作者 LI Ming-ju Sultan Habibullah Khan Muhammad Kashif 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第11期2483-2491,共9页
Genetic diversity is the base of any genetic improvement breeding program aimed at stress breeding.The variability among breeding materials is of primary importance in the achievements of a good crop production.Herein... Genetic diversity is the base of any genetic improvement breeding program aimed at stress breeding.The variability among breeding materials is of primary importance in the achievements of a good crop production.Herein,105 wheat genotypes were screened against drought stress using factorial completely randomized design at seedling stage to determine the genetic diversity and traits association conferring drought tolerance.Analysis of variances revealed that all the studied parameters differed significantly among all genotypes,indicating the significance genetic variability existed among all genotypes for studied indices.The 10 best performance genotypes G1,G6,G11,G16,G21,G26,G39,G44,G51,and G61 were screened as drought tolerant,while five lowest performance genotypes G3,G77,G91,G98,and G105 were screened as drought susceptible.Root length,chlorophyll a,chlorophyll b,and carotenoid contents were significantly correlated among themselves which exhibited the importance of these indices for rainfed areas in future wheat breeding scheme.Shoot length exhibited non-significant and negative association with other studied traits,and its selection seems not to be a promising criteria for this germplasm for drought stress.Best performance genotypes under drought stress conditions will be useful in future wheat breeding program and early selection will be effective for developing high yielding and drought tolerant wheat varieties. 展开更多
关键词 drought photosynthesis CHLOROPHYLL wheat SEEDLING CAROTENOID
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基于叶面叶绿素分布特征的黄瓜叶片氮钾元素亏缺诊断 预览
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作者 石吉勇 李文亭 +3 位作者 郭志明 黄晓玮 李志华 邹小波 《农业机械学报》 EI CAS CSCD 北大核心 2019年第8期264-269,共6页
利用高光谱图像技术无损表征黄瓜叶片的叶绿素分布特征,并将其作为N、K元素亏缺诊断依据。采集黄瓜叶片的高光谱图像数据,利用高效液相色谱法分析黄瓜叶片的叶绿素含量,利用遗传算法建立叶片高光谱图像信号与叶绿素含量的对应关系,进而... 利用高光谱图像技术无损表征黄瓜叶片的叶绿素分布特征,并将其作为N、K元素亏缺诊断依据。采集黄瓜叶片的高光谱图像数据,利用高效液相色谱法分析黄瓜叶片的叶绿素含量,利用遗传算法建立叶片高光谱图像信号与叶绿素含量的对应关系,进而实现黄瓜叶片叶绿素分布图的无损检测。与对照组叶片的叶绿素分布图相比,缺N叶片主要表现为叶片中心区域叶绿素含量偏低,而缺K叶片主要表现为叶片边缘的局部区域叶绿素含量偏低。据此分别提取缺N、缺K叶片及对照组叶片的叶绿素及其分布特征(叶片中心区域所有像素点的叶绿素含量均值、叶片边缘区域叶绿素含量偏低的像素点数量),并借助提取的特征参数建立了N、K元素亏缺诊断方法,其正确诊断率为95%。研究结果表明,叶绿素叶面分布特征可有效实现黄瓜植株N、K元素的亏缺诊断。 展开更多
关键词 黄瓜叶片 叶绿素 分布特征 氮元素 钾元素 高光谱成像
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