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陆地生态系统臭氧通量观测和气孔吸收估算研究进展 总被引:1,自引:0,他引:1
近地面大气中臭氧(O3)对植物生长发育和产量会产生不良影响。工业和交通排放的增加使得全球地面O3浓度逐年增加,不断升高的O3浓度已开始影响到我国的粮食产量。O3对植物的影响是由于其进入植物体内发生生化反应所引起的,所以需要建立一种考虑到植物生理生态状况的评估指标来评估O3对植物的影响。其中基于O3通量(特别是植物气孔吸收)的评价指标和方法,被认为比传统的基于O3浓度的评价指标和方法更符合O3对植物的影响机理。介绍了O3对生态系统影响评估方法和评价指标,重点评述了生态系统尺度O3通量观测和气孔吸收估算的主要方法以及在不同生态系统上的研究进展分析了我国关于O3对植物和生态系统影响的研究现状,并对未来的研究工作进行了展望。 相似文献
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Hua Ma Li-Juan Cui Wei Li Yu Ning Yin-Ru Lei Xu Pan Yi-Fei Wang Man-Yin Zhang 《Journal of Plant Ecology》2022,15(1):208
每日盐度波动对真盐生植物盐地碱蓬种内相互作用沿盐度梯度的影响
土壤盐度的异质性是河口潮间带的一个突出的环境特征,影响植物的生长和盐沼中生物相互作用的转变。本研究旨在探究盐度梯度和盐度波动对一种真盐生植物的种内相互作用的交互影响。 相似文献
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植物在个体发育的各个阶段都与不同的群落成员相互作用,如竞争的植物、有益的传粉者和敌对的植食动物。昆虫植食在各类生态系统中普遍存在,并可能对植物有性生殖产生各种影响。植食昆虫可通过对植物有性生殖结构的消耗直接对植物生殖产生影响,也可通过影响植物资源分配和花性状等改变传粉者服务,从而间接对植物有性生殖带来正面、负面或中性的影响。同一植物的植食昆虫和传粉者往往对植物的吸引性状 (如花大小、气味、颜色等)有相同的偏好,因此植食者与传粉者均能对植物有性生殖性状施加选择压力。本文从昆虫植食对植物有性生殖的直接影响、间接影响以及植食昆虫对植物有性生殖性状选择的影响三个方面进行综述,以期为昆虫植食和生物资源多样性保护相关研究提供参考。 相似文献
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该研究利用谱系独立比较法(Phylogenetically Independent Contrasts,PIC)和Wilcoxon秩和检验法,分析中国科学院植物研究所植物园(39°54'N,116°12'E)中的84个物种170株个体的传粉方式和果实类型对木本开花时间和结实时间的影响,其中Wilcoxon秩和检验法检验的结果作为PIC检验结果的参考。结果表明:(1)传粉方式显著影响植物开花和结实时间,风媒花植物比虫媒花植物开花和结实早;(2)果实类型对结实时间的影响在考虑和不考虑物种间系统发育关系时表现不同,当不考虑物种间系统发育关系时,肉质果实植物结实时间比非肉质果实植物早;(3)不同的传粉方式间以及不同的果实类型间植物的花果间隙期无显著差异,但本研究结果显示肉质果实植物结实时间比非肉质果实植物大约早20d。由此推论:(1)植物固有属性,如传粉方式和果实类型,会影响植物繁殖物候,且不同的属性影响强度不同;(2)与某一特定物候期或繁殖器官相关性大的属性对该物候期的影响可能更大,如传粉方式对开花时间的影响可能大于其对结实时间的影响,而果实类型对结实物候期的影响更大。 相似文献
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《生态学杂志》2017,(7)
丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF)帮助宿主植物吸收土壤养分和水分,促进植物的生长。研究表明,AMF可影响宿主植物根系的特征,但AMF对宿主植物的生长效应与根系特征的变化效应是否有关,目前仍不清楚。本文采用整合分析(Metaanalysis)的方法,探讨AMF对双子叶植物生长和根系特征的影响以及二者的相关性,并分析AMF的这一影响是否受土壤磷素水平(Olsen-P)的调节。结果表明:AMF显著增加双子叶植物的总生物量、地上部分和地下部分生物量;AMF增加了双子叶植物根长、根面积和根体积,但降低了比根长;AMF对植物的这些影响受土壤磷水平调节,土壤低磷和中磷水平下AMF对植物的生长效应大于土壤高磷水平下的处理,而对根系特征的影响效应在中磷水平下高于低磷和高磷水平的处理。相关性分析结果表明,AMF对双子叶植物生长的影响与对根长、根体积的影响呈显著正相关,在低磷水平下根长对AMF的响应与植物生长的响应(MGR)具有更高的正相关性。本研究结果预示,AMF对宿主植物生长的效应可能通过改变根系特征实现碳的合理分配和从土壤中获得更多的水和养分等资源。 相似文献
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丛枝菌根真菌在外来植物入侵演替中的作用与机制 总被引:1,自引:0,他引:1
外来植物入侵不仅是环境、经济和社会问题,也是一个生理学和生态学问题,尤其是入侵植物与本地植物、入侵植物和本地土壤生物之间的相互作用决定外来植物入侵程度。丛枝菌根真菌(AMF)作为土壤中一类极为重要的功能生物,在外来植物入侵演替过程中发挥多种不同作用。文章系统总结了AMF对入侵植物个体和群体的影响,入侵植物与本地植物竞争中AMF发挥的促进和抑制作用;探讨了AMF与入侵植物的相互作用关系,以及环境因子对AMF一入侵植物关系的影响:对AMF在外来植物入侵演替中的作用机制进行了讨论。旨在为探索控制生物入侵的新途径、为我国开展外来植物入侵研究与防控实践提供新思路。 相似文献
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为探究极端气候事件对植物的影响,对澳门九澳山海滨群落10种植物2012-2017年盛花期物候进行了观察。结果表明,植物的盛花期一般在3-9月,其中有4种植物为5月。2013和2016年早春澳门的极端强降水使植物的盛花期出现了明显的提前或者推迟。9种植物的盛花期与盛花期前0~2个月和上一年的秋冬季的月均温度或月降水存在显著相关性。温度和降水对植物盛花期的影响差异不大,但晚花植物对降水更加敏感。这为澳门和邻近岛屿的生态恢复和园林树种选材提供参考。 相似文献
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Yamamura N Fujita N Hayashi M Nakamura Y Yamauchi A 《Journal of theoretical biology》2007,246(3):530-537
Plants show phenological responses to herbivory. Some enclosure experiments have demonstrated that the onset of the peak flowering season is dependent on grazing pressure. We constructed a mathematical model using Pontryargin's maximum principle to investigate changes in flowering time by examining shifts in resource allocation from vegetative to reproductive plant components. We represented a primary production of a plant individual by two types of function of vegetative part size, a linear function and a convex non-linear function. The results of a linear production model indicate that optimal phenology follows a schedule that switches from the production of vegetative parts to that of reproductive parts at a given time ('bang-bang' control). However, in a non-linear model, a singular control, wherein the plant invests in both productive and reproductive parts, may be included between obligate production and reproduction periods. We assumed that the peak of the flowering season occurs immediately following the exclusive investment in reproduction. In a linear production model, differential herbivory rates on the vegetative and reproductive parts of a plant resulted in shifts in the peak flowering time. A higher herbivory rate on the vegetative components advanced the peak, whereas it was delayed when grazing pressure focused on reproductive components of the plant. In the non-linear production model, increased grazing pressure tended to postpone the flowering peak. These results corresponded well with results of enclosure experiments, thus suggesting adaptive control of flowering time in plants. 相似文献
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Theory predicts that consumers may stabilise or destabilise plant production depending on model assumptions, and tests in aquatic food webs suggest that trophic interactions are stabilising. We quantified the effects of trophic interactions on temporal variability (standard deviation) and temporal stability (mean/standard deviation) of grassland biomass production and the plant diversity–stability relationship by experimentally removing heterotrophs (large vertebrates, arthropods, foliar and soil fungi) from naturally and experimentally assembled grasslands of varying diversity. In both grassland types, trophic interactions proportionately decreased plant community biomass mean and variability over the course of 6 years, leading to no net change in temporal stability or the plant diversity–stability relationship. Heterotrophs also mediated plant coexistence; their removal reduced diversity in naturally assembled grasslands. Thus, herbivores and fungi reduce biomass production, concurrently reducing the temporal variability of energy and material fluxes. Because of this coupling, grassland stability is robust to large food web perturbations. 相似文献
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Abstract.— Can the evolution of plant defense lead to an optimal primary production? In a general theoretical model, Loreau (1995) and de Mazancourt et al. (1998, 1999) have shown that herbivory could increase primary production up to a moderate rate of grazing intensity through recycling of a limiting nutrient, provided several conditions are fulfilled. In the present paper, we assume: (1) grazing intensity is controlled by plants through their level of palatability; and (2) plant fitness is determined by its productivity. We explore the conditions under which such an optimal production may be reached through natural selection. We model two competing plant types that differ only in palatability and are distributed in a patchy landscape determined by the plant‐herbivore interaction. Patch size is determined by herbivore behavior: herbivores recycle nutrient homogeneously within patches, but recycle nutrient proportionally to consumption between patches. The model shows that a strategy of intermediate palatability can be adaptive in response to a small herbivore that lives on and recycles nutrient around one or a few individual plants. For moderately small herbivores, plant palatability may evolve towards one of two local convergent strategies, depending on the initial conditions. For medium‐ to large‐sized herbivores, the nonpalatable strategy is always selected. We discuss the functional and evolutionary implications of these results, and suggest that the traditional dichotomy describing antagonistic and mutualistic interactions may be misleading. 相似文献
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A new method for calculating the assimilate distribution between plant shoots and roots in dynamic models of production process for agricultural crops is suggested. The method is based on direct calculation of the dynamics of photosynthate accumulation and absorption rates of nitrogen compounds in the plant root system. The hypothesis underlying this method is that all mobile compounds entering the plant are completely utilized for the production of structured biomass. Unlike the method of distribution keys, which is widely used in similar models, the suggested procedure accounts for adaptive plant responses to both uncontrolled weather conditions and mineral nutrition. The suggested method was implemented as software within the framework of Agrotool (version 3) simulation system. Verification of the method in many years' field experiments with barley confirmed its efficiency and showed a satisfactory accuracy of model calculations. 相似文献
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Environmental parameters influencing phenolics production by batch cultures of Nicotiana tabacum 总被引:2,自引:0,他引:2
The influence of temperature, illumination, hormonal levels (2,4-D and kinetin), carbon to nitrogen ratios, antibiotics, and precursor feeding on phenolics production by Nicotiana tabacum (tobacco) was studied. This plant cell system was chosen as a model system to learn more about secondary product formation in plant cell tissue cultures. This is the first study to manipulate all of these environmental parameters with a single plant cell system. The most striking results were with 2,4-D manipulation. The removal of 2,4-D resulted in significant phenolics production during the stationary phase, while normal levels strongly suppressed phenolics production during the stationary phase. The addition of phenylalanine stimulated phenolics production per gram of cells but strongly inhibited growth. 相似文献
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Pascal F Dagot C Pingaud H Corriou JP Pons MN Engasser JM 《Biotechnology and bioengineering》1995,46(3):202-217
The aim of the present study was the development of a general simulation module for fermentation within the framework of existing chemical process simulators. This module has been applied to an industrial plant which produces ethanol from beet molasses and fresh beet juice by Saccharomyces cerevisiae. An unstructured mechanistic model has been developed with kinetic laws that are based on a chemically defined reaction scheme which satisfies stoichiometric constraints. This model can be applied to different culture conditions and takes into account secondary byproducts such as higher alcohols. These byproducts are of prime importance and need to be correctly estimated because a sequence of distillation columns follow the fermentor in the plant. Important measurement campaigns have been performed on the plant to validate the model. Plant operation has been successfully simulated using the same kinetic model for both continuous and fed-batch modes of production. (c) 1995 John Wiley & Sons, Inc. 相似文献
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Mikschofsky H Heilmann E Schmidtke J Schmidt K Meyer U Leinweber P Broer I 《Plant molecular biology》2011,76(1-2):131-144
The production of plant-derived pharmaceuticals essentially requires stable concentrations of plant constituents, especially recombinant proteins; nonetheless, soil and seasonal variations might drastically interfere with this stability. In addition, variability might depend on the plant organ used for production. Therefore, we investigated the variability in plant constituents and antigen expression in potato plants under greenhouse and field growth conditions and in leaves compared to tubers. Using potatoes expressing VP60, the only structural capsid protein of the rabbit haemorrhagic disease virus (RHDV), CTB, the non-toxic B subunit (CTB) of the cholera toxin (CTA-CTB(5)) and the marker protein NPTII (neomycinphosphotransferase) as a model, we compare greenhouse and field production of potato-derived antigens. The influence of the production organ turned out to be transgene specific. In general, yield, plant quality and transgene expression levels in the field were higher than or similar to those observed in the greenhouse. The variation (CV) of major plant constituents and the amount of transgene-encoded protein was not influenced by the higher variation of soil properties observed in the field. Amazingly, for specific events, the variability in the model protein concentrations was often lower under field than under greenhouse conditions. The changes in gene expression under environmental stress conditions in the field observed in another event do not reduce the positive influence on variability since events like these should excluded from production. Hence, it can be concluded that for specific applications, field production of transgenic plants producing pharmaceuticals is superior to greenhouse production, even concerning the stability of transgene expression over different years. On the basis of our results, we expect equal or even higher expression levels with lower variability of recombinant pharmaceuticals in the field compared to greenhouse production combined with approximately 10?times higher tuber yield in the field. 相似文献
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Esmaeil Bakhshandeh Fatemeh Hosseini Sanehkoori Hamidreza Ghorbani Ghorban Ali Nematzadeh Mansour Sekrafi Raoudha Abdellaoui Mohammad Yaghoubi Khanghahi Carmine Crecchio 《The Annals of applied biology》2023,183(1):23-32
To date, there has been little agreement on supporting the hypothesis that how some key vegetative traits of camelina (Camelina sativa (L.) Crantz var. ‘Soheil’) are dependent on plant biomass. Therefore, the main aim of this investigation was to quantify the relationship between the size of camelina plants and seed production across a broad-range of plant densities through modelling approaches. To make a wide range of plant densities, a fan design was used in eight replicates in an experimental field at Sari Agricultural Sciences and Natural Resources University, Iran. To quantify the relation between plant density and other plant traits, a regression analysis was carried out and the coefficient of determination (R2) was considered to evaluate the goodness of fit model. A power model (y = axb) could describe well the relationship between plant density (ranged 113–2905 plants m−2) and plant biomass, seed production, number of seeds per plant, stem diameter, and siliques number, with the coefficient of determination (R2) values of 0.85, 0.87, 0.65, 0.64, and 0.90, respectively. The harvest indexes were 13.8%–26.9%, depending on plant density. Seed production per plant was positively correlated to the siliques number (r = 0.85), the branch number (r = 0.80), and the seed number (r = 0.99) which could be key components of camelina seed production per plant. Furthermore, no significant correlation was found among plant height, thousand-seed weight, and harvest index with seed production per plant. In conclusion, plant biomass could be considered an important trait to predict plant growth models of camelina. Also, a lower plant density of camelina can be compensated by a greater number of siliques, branches and seeds per plant. 相似文献
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BACKGROUND AND AIMS: The dynamical system of plant growth GREENLAB was originally developed for individual plants, without explicitly taking into account interplant competition for light. Inspired by the competition models developed in the context of forest science for mono-specific stands, we propose to adapt the method of crown projection onto the x-y plane to GREENLAB, in order to study the effects of density on resource acquisition and on architectural development. METHODS: The empirical production equation of GREENLAB is extrapolated to stands by computing the exposed photosynthetic foliage area of each plant. The computation is based on the combination of Poisson models of leaf distribution for all the neighbouring plants whose crown projection surfaces overlap. To study the effects of density on architectural development, we link the proposed competition model to the model of interaction between functional growth and structural development introduced by Mathieu (2006, PhD Thesis, Ecole Centrale de Paris, France). KEY RESULTS AND CONCLUSIONS: The model is applied to mono-specific field crops and forest stands. For high-density crops at full cover, the model is shown to be equivalent to the classical equation of field crop production (Howell and Musick, 1985, in Les besoins en eau des cultures; Paris: INRA Editions). However, our method is more accurate at the early stages of growth (before cover) or in the case of intermediate densities. It may potentially account for local effects, such as uneven spacing, variation in the time of plant emergence or variation in seed biomass. The application of the model to trees illustrates the expression of plant plasticity in response to competition for light. Density strongly impacts on tree architectural development through interactions with the source-sink balances during growth. The effects of density on tree height and radial growth that are commonly observed in real stands appear as emerging properties of the model. 相似文献