成都市沙河主要绿化树种固碳释氧和降温增湿效益

以成都市沙河植物廊道广泛应用的8种绿化植物为材料,利用LI-6400XT便携式光合测定系统进行了光合生理生态指标的测定,并对其固碳释氧与降温增湿效应进行了量化研究.结果表明:整个生长季节同类植物各季节的单位叶面积固碳释氧和 降温增湿能力表现出夏季＞秋季＞春季.日固碳释氧能力由强到弱为桂花、垂柳、香樟、黄葛树、山杜英、银杏、天竺桂、水杉,年固碳释氧能力由强到弱为垂柳、香樟、黄葛树、银杏、桂花、天竺桂、水杉、山杜英,日降温增湿效果由强到弱为垂柳、山杜英、水杉、天竺桂、黄葛树、香樟、银杏、桂花.据估算,整个沙河植物群落中乔木树种年总固碳量约为5.87×104 t,总释氧量约为4.27×104 t.根据对主要树种固碳释氧和降温增湿能力的分析表明,在树种配置时,垂柳、桂花、山杜英、香樟为优选乔木树种,而银杏的固碳释氧和降温增湿能力较弱,可作为长寿树种和观赏树种适量引种,不宜大面积绿化.     

武汉市65个园林树种的生态功能研究

园林树种是建设生态园林城市的主体,其生态功能的定量研究是园林植物筛选、配置和管理的重要依据.本研究通过测量武汉市65个常见园林树种的光合、蒸腾日变化及冠幅、叶面积指数等指标,发现树种间、乔木与灌木、常绿与落叶植物之间的水分利用、固碳释氧、蒸腾降温及滞尘能力均有显著差异.根据分层聚类分析,可将它们划分为5大功能类群.其中低固碳低滞尘型26种;高固碳高降温型8种(分别为垂柳Salix babylonica、火棘Pyracantha fortuneana、栾树Koelreuteria paniculata、木芙蓉Hibiscus mutabilis、枇杷Eriobotrya japonica、西府海棠Malus micromalus、银木Cinnamomum septentrionale和重阳木Bischofia javanica);高滞尘低降温型9种(分别为枫杨Pterocarya stenoptera、桂花Osmanthus fragrans、夹竹桃Nerium indicum、马褂木Liriodendron chinense、石楠Photinia serrulata、悬铃木Platanus hispanica、雪松Cedrus deodara、银杏Ginkgo biloba和樟树Cinnamomum camphora);低水分利用高蒸腾型11种;高水分利用型11种.     

广州市6种攀援植物降温增湿效应研究

对广州市常用的6种攀援植物进行叶面积指数、光合速率和蒸腾速率测定,比较分析其释氧固碳和降温增湿效益。结果表明,簕杜鹃Bougainvillea spectabilis单位绿地面积固碳释氧量最大,降温效果最明显;异叶爬墙虎Parthenocissus dalzielii增湿效果最好。在园林绿化中,城市立体绿化攀援植物可首选异叶爬墙虎、使君子Quisqualis indica和簕杜鹃。     

呼和浩特市13种绿化植物固碳释氧效率的比较研究

以呼和浩特市的13种主要城市绿化植物为研究对象,采用LI-6400光合仪对植物的光合生理生态指标进行测定,对其固碳释氧效率进行量化研究,以探讨植物光合作用固定二氧化碳和释放氧气的效率,分析影响固碳释氧效率的因素,明确各植物的固碳释氧效率,为半干旱地区的城市绿化提供科学理论依据。结果显示:(1)不同植物的日光合速率的变化趋势不同,其中早熟禾、萱草、叉子圆柏、侧柏、云杉、圆柏、油松为单峰曲线,芍药、连翘、紫丁香、国槐、垂柳、新疆杨为双峰型;而在6月到11月中各植物的固碳量变化趋势表现基本相同,固碳量的高值出现在6月前后和9月前后。(2)植物固碳量排序为:连翘国槐新疆杨紫丁香油松叉子圆柏圆柏芍药萱草垂柳侧柏云杉早熟禾。(3)植物的固碳量与光合速率、蒸腾速率、空气温度、叶片温度之间均呈极显著相关关系。研究表明,在半干旱地区的城市绿化植物配置时,应优选固碳释氧相对较强的植物(落叶乔木为国槐、常绿乔木为油松,灌木为连翘,草本为芍药),而固碳释氧能力较弱的植物可作为长寿植物种和观赏植物种选种。     

5种阔叶树的光合生理生态特性研究

对核桃楸、水曲柳、黄波罗、紫椴和白桦的光合生理生态特性研究表明,随着幼叶成长、叶绿素含量的增加,各树种光合能力与硝酸还原酶活力也增加．晴天,白桦与水曲柳光合曲线呈双峰,其余３树种呈单峰,阴雨数日转睛后,白桦与水曲柳光合曲线呈单峰,其余３树种呈双峰;阴天,５个树种光合曲线均与光照曲线相似．幼叶成长过程中硝酸还原酶活力与光合速率呈正相关;各树种的光合速率除受光的影响外,空气相对湿度是光能利用的限制因子．     

上海新江湾地区废弃地低干扰植物群落优势树种的光合生理生态特征

以上海市杨浦区原废弃地(新江湾地区)半自然群落的主要优势树种为对象,测定不同生活型植株在夏季不同生境下叶片的光合特性,从光合生理生态角度分析低干扰条件下上海城市废弃地的植物群落次生演替过程的特点,并结合环境因子分析并预测植物群落结构的动态变化。结果表明:(1)冠层树种光合作用日变化曲线呈双峰型,林窗树种呈单峰型,而林下树种呈不规则变化,体现出亚热带地区植物在夏季典型气候下的"光合午休"现象,而生境特点同时也影响植物光利用对策。(2)冠层成年树以落叶树种刺槐和朴树的日均净光合速率最高,且具有较高的光饱和点;在林下生境中,以强耐阴灌木植物胡颓子的日均净光合速率最高,其次为常绿树种香樟和女贞的幼树和幼苗,而林下落叶树种日均净光合速率均较低。(3)影响冠层树种的净光合速率因子中,生态因子是第一主成分,而对于林窗树种,第一主成分则是生理因子。(4)由于阳性落叶树种具有更高效的光合效率,能迅速占领上层空间,新江湾区域人为低干扰植物群落的演替早期均以扩散能力较强的先锋性树种为主;乔木群落形成后,林下更新苗则以光适应范围较宽的香樟、女贞为主,同时,上层落叶树种大规模自然衰退使得香樟和女贞逐步替代落叶树种。     

浙北地区常见绿化树种光合固碳特征

高固碳能力的树种选择是营造优质碳汇林,发展碳汇林业的重要基础工作.以浙北地区常见的30种造林绿化树种为研究材料,利用LI-6400便携式光合测定仪,测定树木光合日变化及不同光强梯度下光合作用的光响应特性,并根据实验观测值进行计算,对30个树种的日净固碳量和光合生理拟合参数进行Ward法聚类分析和因子分析.结果表明:香樟的固碳量最大((11.374±1.020) g·m-2·d-1),其次为碧桃、垂柳、石栎、无患子,固碳量最小的为红叶李((2.178±0.605) g·m-2·d-1),香樟和红叶李的日净固碳量有极显著差异(P＜0.01);树木的生理特性指标分析进一步反映了树种在浙北地区生长适应性及固碳能力大小,同时,根据树木的生理特性指标进行因子分析和聚类分析的结果,香樟、碧桃在浙北地区生长适应性较好,其次为无患子、垂柳、女贞等;根据树种固碳量及生理指标综合测定分析,建议在浙北地区造林绿化中可以优先选用香樟、碧桃、垂柳、无患子、石栎、女贞这些树种.     

濒危植物银缕梅(Parrotia subaequalis)不同径级个体的光合能力差异与更新限制

银缕梅(Parrotia subaequalis)是我国华东地区特有种,属国家Ⅰ级濒危保护植物.分别于5月份与8月份采用Li-6400光合系统测定了江苏宜兴龙池大垅西芥银缕梅种群内大 (胸径＞10 cm)、中 (2 cm＜胸径≤10 cm)、幼 (胸径≤2 cm) 3个径级个体的光合生理参数、光合-光强响应曲线及光环境因子,探讨了不同径级个体的光合能力差异及其对种群更新的影响.结果表明:幼树最大净光合速率(Pnmax)、光饱和点(LSP)、光补偿点(LCP)和暗呼吸速率(RD) 显著低于大树与中树,但比叶面积(SLA)显著高于大树及中树;低LCP、低RD与高SLA是银缕梅幼树对弱光环境做出的适应性反应.中树LSP仅为大树的二分之一,而其LCP与大树无明显差异,且显著高出幼树;中树LSP与LCP之间的光能利用区间极为狭窄;中树全天平均接受的RAR稍高于LCP,但远低于其LSP;同时,中树的SLA显著低于幼树与大树,致使中树全天碳同化总量严重不足.基于净光合速率(Pn)与光环境参数建立的逐步回归方程进一步证实了光合有效辐射(PAR)对Pn的贡献最大,是影响银缕梅光合碳同化能力的关键因子.由于幼树与中树受到大树遮荫,叶片上方的光合有效辐射均显著降低.尽管银缕梅幼苗在林下表现出较强的弱光适应能力,但在后期建成为中树的过程中,叶片形态与光合生理特性均表现出对遮萌环境的不适应,光资源不足构成银缕梅种群更新的主要限制因子,导致种群的中等径级个体急剧减少.人为干预以形成适宜的林窗环境,有利于银缕梅幼树的后期生长,并促进银缕梅种群的顺利更新.     

淮南市9种园林灌木树种夏季光合特性研究

采用TPS-2便携式光合仪对淮南市9种园林绿化灌木树种的夏季光合特性进行了测定。结果表明, 各树种光合生理参数(Pn、Ci、Tr、Gs、Ls、WUEt)日均值差异显著, 日变化趋势不尽相同, 且金边黄杨和腊梅的Pn日变化曲线为双峰曲线, 桂花的Pn日变化曲线为三峰曲线, 皆出现了“光合午休”现象。根据Pn、Tr、WUEt 3个指标的日均值进行聚类分析, 可将供试树种分为3个类群。Ⅰ类为低光合、低水分利用型(桂花、红檵木、金边黄杨、腊梅、紫荆、紫叶李), Ⅱ类为低蒸腾、高水分利用型(栀子), Ⅲ类为高光合、高蒸腾型(海桐、紫薇)。从生态效益的角度出发, 海桐和紫薇的固碳释氧、降温增湿能力俱佳, 节水降耗效果处于中等水平, 可作为淮南市生态园林建设的优先树种。     

翅果油树叶性特征的动态变化

以山西翼城翅果油树(Elaeagnus mollis)自然保护区的翅果油树为研究对象,利用LI-3000A叶面积测定仪测量其单叶面积,用Li-6400便携式光合作用测定系统测定单位叶面积饱和光合速率(Aaraa),用H2SO4-H2O2消煮法测定叶氮含量,计算叶性参数比叶面积(SLA)、单位叶重量饱和光合速率(Amass)、光合氮利用率(PNUE)和单位重量叶氮含量(Nmass)的值,并研究它们与径级之间的关系.结果表明:随着翅果油树径级的增加,SLA、Nmass、Aarea、Amass和PNUE值先下降后上升,当翅果油树径级为7.5 cm左右时,SLA、Nmass、Aarea、Amass和PNUE值均降到最小值,表明径级为7.5 cm左右的翅果油树其光合能力最弱、光合氮利用率较低且生存压力较大.翅果油树叶性参数是研究翅果油树种群动态变化的有效指标,可为研究翅果油树种群动态提供更为便捷的方法.     

Numerical approaches towards life cycle interpretation five examples

The ISO-standard for LCA distinguishes four phases, of which the last one, the interpretation, is the least elaborated. It can be regarded as containing procedural steps (like a completeness check) as well as numerical steps (like a sensitivity check). This paper provides five examples of techniques that can be used for the numerical steps. These are the contribution analysis, the perturbation analysis, the uncertainty analysis, the comparative analysis, and the discernibility analysis. All five techniques are described at a non-technical level with respect to basic concept, possibilities, tabular and graphical representation, restriction and warnings, and all are illustrated with a simple example.     

影响水稻光合日变化的酶和相关因素的分析

水稻叶片的最大光合速率出现在上午１０：００时,Ｒｕｂｉｓｃｏ初始活力也在此时达到最大,然后逐渐降低,下午１４：００时略上升后又下降．Ｒｕｂｉｓｃｏ初始活力与光合速率之间极显著相关,相关系数为 ０．９４７４．运用相关性分析、回归分析、通径分析,对晴（有时有云）天气水稻叶片的光合速度、光合关键酶及有关因素的日变化进行综合评估,结果发现中午光合下降主要来自气孔限制,同时Ｒｕｂｉｓｃｏ活性也下降;Ｒｕｂｉｓｃｏ活性是影响光合日变化的又一重要生化因子．体内Ｒｕｂｉｓｃｏ活性受Ｒｕｂｉｓｃｏ活化酶的调节．     

Discrimination of higher plant calluses based on embryogenic capacity and taxonomic classification by pyrolysis mass spectrometry

Pyrolysis mass spectrometry (PyMS) is a rapid, simple, high-resolution analytical method based on thermal degradation of complex material in a vacuum, and has been widely applied to the discrimination of closely related microbial strains. Minimally prepared samples of embryogenic and non-embryogenic calluses derived from various higher plants (sweet potato, morning glory, Korean ginseng, Siberian ginseng, and balloon flower) were subjected to PyMS for spectral fingerprinting. A dendrogram based on the unweighted pair group method, with arithmetic mean of pyrolysis mass spectra, divided the calluses into Siberian ginseng embryogenic callus and the others, which were subsequently divided into embryogenic and non-embryogenic callus groups, regardless of plant species from which the calluses were derived. In the non-embryogenic callus group, the dendrogram was in agreement with the known taxonomy of the plants. These results indicate that PyMS analysis could be applied for discriminating plant calluses based on embryogenic capacity and taxonomic classification.     

Intraspecific variation in Licuala glabra Griff. (Palmae) in Peninsular Malaysia– a morphometric analysis

We studied vegetative and reproductive characters of 74 herbarium specimens of Licuala glabra Griff. (Palmae) collected from 22 localities throughout Peninsular Malaysia. To test the null hypothesis that there are no distinct groups within the species, cluster analysis (nearest neighbour), principal coordinates and principal components analyses were performed on the set of 43 qualitative and quantitative characters. The results obtained suggested that: (1) there are three infraspeciflc groups within the species, viz., the two published varieties glabra and selangorensis as well as a possible third novel taxon; (2) there is clustering of individuals corresponding to their geographic localities; (3) clusters generated using only reproductive characters indicate a biogeographic distribution of populations correlated with the mountain ranges in the peninsula.     

Fish ecoregions of Kansas: stream fish assemblage patterns and associated environmental correlates

Synopsis Principal components analysis was performed on fish presence/absence data for 39 common fish species from 410 stream sites in Kansas. The analysis confirmed ten ecologically meaningful fish assemblages, based on species associations. Factor scores based on these assemblages were then clustered into six geographic areas or fish ecoregions. Canonical discriminant analysis identified environmental variables that distinguished the derived fish ecoregions. Mean annual runoff, mean annual growing season, and discharge appear most important. Mean width, mean depth, chloride concentration, water temperature, substrate type, gradient, and percent of pool habitat were less important. Correspondence exists between these fish ecoregions and the patterns of physiographic regions, river basins, geology, soil, and potential natural vegetation in Kansas. The multivariate statistical approach used to classify fish ecoregions should have considerable potential value for fish assessment and management purposes in areas other than the state of Kansas.     

Some remarks about the analysis of active control studies

In an active-controlled trial, the experimental treatment can be declared to be non-inferior to the control if the confidence interval for the difference excludes a fixed pre-specified margin. Recently, some articles have discussed an alternative method where the data from the current study and placebo-controlled studies for the active control are combined together into a single test statistic to test whether a fixed fraction of the effect of the active control is preserved. It has been shown that, conditional on nuisance parameters from the active-controlled study, a fixed margin can be defined that will be operationally equivalent to this latter method. In this article, we will discuss statistical properties associated with these approaches. Specifically, the interim monitoring boundaries and level of evidence will be considered.     

Normal Approximations of Exact Tests in Configural Frequency Analysis

The most common tests for types and antitypes in configural frequency analysis are normal approximations of exact tests. In the paper such statistics under the complete independence model and under the fixed margins model are discussed. It turns out that these test statistics are not acceptable when the number of simultaneously performed tests is large or when the expected frequencies are small. In these cases, the use of exact tests is advocated and some existing computer programs for such tests are indicated. A normal approximation based on the strong version of the De Moivre-Laplace limit theorem is also discussed. Empirical examples are given from longitudinal data describing psychological development of boys.     

Phenotypic evaluation of genetic variability and selection of yield contributing traits in chickpea recombinant inbred line population under high temperature stress

Heat is a major abiotic stress that drastically reduces chickpea yield. This study aimed to identify heat-responsive traits to sustain crop productivity by screening a recombinant inbred line (RILs) population at two locations in India (Ludhiana and Faridkot). The RIL population was derived from an inter-specific cross between heat-tolerant genotype GPF 2 (C. arietinum L.) and heat sensitive accession ILWC 292 (C. reticulatum). The pooled analysis of variance showed highly significant differences for all the traits in RILs and most of the traits were significantly affected by heat stress at both locations. High values of genotypic coefficient of variation (19.52–38.53%), phenotypic coefficient of variation (20.29–39.85%), heritability (92.50–93.90%), and genetic advance as a percentage of mean (38.68–76.74%) have been observed for plant height, number of pods per plant, biomass, yield, and hundred seed weight across the heat stress environments. Association studies and principal component analysis showed a significant positive correlation of plant height, number of pods per plant, biomass, hundred seed weight, harvest index, relative leaf water content, and pollen viability with yield under both timely-sown and late-sown conditions. Path analysis revealed that biomass followed by harvest index was the major contributor to yield among the environments. Both step-wise and multiple regression analyses concluded that number of pods per plant, biomass and harvest index consistently showed high level of contribution to the total variation in yield under both timely-sown and late-sown conditions. Thus, the holistic approach of these analyses illustrated that the promising traits provide a framework for developing heat-tolerant cultivars in chickpea.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12298-021-00977-5.     

分子水平的遗传多样性及其测量方法

遗传多样性水平是一项很重要的数据。目前从分子水平量化遗传多样性的方法以等位酶分析、ＲＦＬＰ分析和ＲＡＰＤ分析为代表。遗传变异在基因组中并非随机分布,所以取样方式对分析结果的影响不容忽视。本文叙述了遗传变异的产生和分布,并以此为基础比较了上述３种分析方法的理论与实践。     

甲醇对酵母过氧化氢酶活性的影响机理研究

将酵母过氧化氢酶加入一定比例的甲醇,测定其活性变化。结果表明:在含2%甲醇时酶活比对照提高4026%。将粗酶液用70%饱和度的硫酸铵盐析后离心所得的上清液再加入硫酸铵至80%饱和度,离心的沉淀溶解在缓冲液中,上SephadexG75柱,分离出的有酶活性的蛋白峰经电泳得一条蛋白带,说明过氧化氢酶已经被提纯到电泳纯。光谱分析发现,甲醇处理后过氧化氢酶纯酶的吸收光谱和荧光发射光谱与未经处理的比较基本不变,而差示光谱出现明显的正峰和负峰。由动力学分析可知,在甲醇中,过氧化氢酶的Vmax和Km值均有不同程度提高 。