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111.
Olov Karlsson Tsutomu Ikeda Takao Kishimoto Kengo Magara Yuji Matsumoto Shuji Hosoya 《Journal of Wood Science》2000,46(3):263-265
Evidence for the presence of lignin-carbohydrate bonds of the benzylic ether type in wood and pulps may be obtained by use of ozonation treatment to selectively degrade the lignin. It was found that the benzyl ether bond in 3-(4-hydroxy-3-methoxyphenyl)-2-(2-methoxy-phenoxy)-3-(methyl--d-glucopyranosid-6-O-yl)-1-propanol was rather stable during ozonation in acetic acid-water-methanol 1631 at 0°C. The corresponding acid, 3,4-dihydroxy-2-(methyl--d-glucopyranosid-6-O-yl)-butanoic acid, was found to be the major reaction product. The use of ozonation followed by acid hydrolysis in connection with studies of lignincarbohydrate linkages is briefly discussed.Part of this paper was presented at the 10th ISWPC, Yokohama, 1999 相似文献
112.
Karl-Heinz Häberle Angela J. Nunn Ilja M. Reiter Herbert Werner Werner Heller Günther Bahnweg Sebastian Gayler Cornelius Lütz Rainer Matyssek 《European Journal of Forest Research》2009,128(2):99-108
To prevent carbon (C) loss to consumers, trees need to defend their primary production. The tree-internal conflict in resource
allocation between growth and defence demands has been the subject of various hypotheses but still requires quantification.
A conceptual approach to approximating the C amount dispensable in favour of primary production at the expense of defence
is demonstrated which is based on nine defence-related metabolite groups. Quantification is exemplified at the level of sun
and shade leaves of adult Fagus sylvatica and Picea abies trees, two species contrasting in foliage type, under oxidative stress as induced by ozone exposure. The difference between
maximum and minimum metabolite levels sampled several times throughout four consecutive growing seasons were conceived as
dispensable between growth and defence-related metabolism and expressed in proportion of the mean annual gross primary production
(GPP) of the foliage. In both species, this proportion amounted to between 2 and 5% of GPP (on a molar C basis). Remaining
uncertainties are discussed as concerning functional overlap of substances between growth and defence-related metabolism,
estimated classification of metabolite turnover rates and “third-party” trade-offs across C demands. Given the complexity
of plant defence, simplification is needed for modelling allocation trade-offs in plants. The presented conceptual approach
meets this need in approximating C transfer capacities between competing physiological demands and in stimulating empirical
assessments towards mechanistic understanding.
This article belongs to the special issue: “Growth and defence of Norway spruce and European beech in pure and mixed stands”. 相似文献
113.
Philip Wipfler Thomas Seifert Peter Biber Hans Pretzsch 《European Journal of Forest Research》2009,128(2):135-144
Several findings indicate an impact of ozone on stem diameter growth leaving the question unanswered, if and how the intra-annual
growth pattern is changed. In this study the hypotheses are tested, that (1) ozone will alter the absolute growth and (2)
alter and shift the period of growth activity within a year. Our data originates from the free air ozone fumigation experiment
‘Kranzberger Forst’ in a mixed stand of Norway spruce and common beech near Freising/Germany. Annual and intra-annual growth
reactions of a sample of five adult beech and five spruce trees, exposed to double ambient ozone were examined and compared
to the same number of untreated reference trees. Diameter increments were measured with plastic diameter girth bands and high-resolution,
automatically logging micro-dendrometers, mounted at breast height (1.3 m). We used the increment data from the growth periods
2000 to 2005. The high-resolution micro-dendrometer data were examined by fitting a Weibull function to the standardized annual
growth profiles to obtain curve parameters for statistical tests. We estimated the parameters ‘T’ which represents the point of time, when 63% of the annual diameter increment is performed and the parameter ‘m’, the Weibull module, which was used as an indicator for the span of time needed to complete the annual growth. The statistical
significance of these curve parameters, together with the absolute diameter increment, was tested by use of mixed regression
models. The analysis of the growth curve parameters revealed a significantly altered intra-annual growth pattern of both species
induced by ozone. Spruce under ozone showed reduced absolute annual diameter increment and a preponed growth activity compared
to untreated trees. Beech’s absolute diameter increment was not affected under ozone, but its growth activity was delayed.
For both species, ozone fumigation did not alter the individual length of the annual growing season. These results are discussed
with respect to drought, tree ring anatomy and tree allometry. The study shows that ozone is able to change growth behaviour
of trees even if increment losses are not obvious.
This article belongs to the special issue "Growth and defence of Norway spruce and European beech in pure and mixed stands". 相似文献
114.
Wheat (Triticum aestivum L.) grain Zn data from six open-top chamber experiments performed in south-west Sweden were combined to study the relationship between Zn accumulation and grain yield, grain protein, and yield components. Treatments included, in addition to open-top chamber controls, elevated CO2, elevated O3, combined CO2 and O3 exposure, combined elevated CO2 and supplemental irrigation, supplemental irrigation, and ambient air comparison plots. The grain Zn concentration was strongly correlated with grain protein (R2 = 0.90) over the range of the experimental treatments, representing non-soil factors. A significant yield dilution effect was found for Zn. For a 10% increase in grain yield, Zn yield was increased by 6.8% on average. Effects on Zn yield correlated strongly with effects on grain protein yield, with a slope close to unity, showing that yield dilution effects for grain Zn and grain protein were similar. Treatment effects on grain Zn concentration were related to effects on grain weight (P < 0.01) and grain number (P < 0.05), but not to harvest index. It was concluded that yield stimulation caused by rising CO2 concentrations is likely to lead to reduced Zn concentrations of wheat grain, thus reducing the nutritional quality. 相似文献
115.
The objective of this study was to develop a simple yet accurate method for the detection of bromate in brackish water. Typically, bromate is measured by ion chromatography; however, the presence of chloride ions complicates bromate detection using this technique. Where bromide ions are naturally present in the source water to be ozonated, either for drinking water or aquacultural purposes, bromate is formed as a disinfection by-product. As such, the need to measure bromate in brackish water is complicated due to the naturally present chloride ions. The study was carried out in a laboratory setting using a UV-spectrophotometer and an ion chromatograph to verify the results. To examine the robustness of the UV-based method, seven water matrices were used to test the bromate detection method. The bromate method presented herein utilizes a reaction of bromate with iodide followed by detection at a UV absorbance at 352 nm. A key finding from the study was that the concentration of bromate was quickly and accurately determined using spectrophotometry. This method successfully measured bromate in waters containing a broad range of conductivity and avoided interference from other anions. The method detection limit reported for all seven water matrices tested was greater than 0.14 mg L−1, which limits the methods utility to saline solutions. 相似文献
116.
Drought and salt are key abiotic stressors in temperate cities. Biogenic volatile organic compound (BVOC) emissions, often dominated by trees, influence the urban troposphere and mediate plant-plant and plant-insect interactions. While knowledge on constitutive BVOC emissions is increasing, modulation of blends by stress has yet received little attention. We thus investigated BVOC blends and herbivore-related subsets (‘bouquets’) of Quercus robur, Fagus sylvatica, Betula pendula and Carpinus betulus seedlings under control, and after 2-weeks of drought and salt stress using PTR-Tof-MS. 22 BVOCs were related to metabolic pathways, and changes among blends and bouquets were assessed. Drought led to a slight increase of isoprene and monoterpene emissions from Q. robur and F. sylvatica, respectively, while total non-isoprene emissions generally declined under water stress. Both drought and salinity led to distinct, species-specific changes in the emission rates of single BVOCs, and resulted in markedly different herbivore-related bouquets in F. sylvatica and C. betulus. Oxygenated VOCs and green leaf volatiles in particular increased in these two salt-sensitive species, while pathway-specific effects were less clear under drought. Findings indicate significant consequences of common urban stressors on BVOC emission spectra, including tropospheric ozone formation and severely hampered plant communication cues under stress. 相似文献
117.
118.
自由空气中臭氧浓度升高对"武运粳21"稻米物性及食味品质的影响 总被引:4,自引:1,他引:4
研究表明不断升高的地表臭氧浓度使作物生长受抑、产量下降, 但对作物品质的影响则不太清楚, 特别是食味品质。本文于2009年和2010年在江苏省江都市小纪镇依托自由空气中臭氧浓度增高(free air ozone concentration enrichment, O3-FACE)技术平台, 以本地主栽水稻品种"武运粳21"为供试材料, 设置大气背景臭氧浓度和高臭氧浓度(比大气背景臭氧浓度高50%)2个水平, 研究了地表臭氧浓度升高对粳稻物性和食味品质的影响。物性分析仪测定结果表明, 高浓度臭氧使熟米硬度平均增加13.6%, 达显著水平。食味计测定结果显示, 高浓度臭氧使稻米香气、光泽、味道、口感和综合值分别下降0.8%(P>0.1)、6.2%(P<0.1)、2.6%(P<0.1)、5.1%(P<0.05)、4.3%(P<0.05), 使完整性增加2.0%(P<0.05)。不同年度间稻米物性和食味品质的差异较大, 但年度与臭氧间的交互作用未达显著水平。以上结果表明, 未来高浓度臭氧环境下生长的稻米蒸煮后将呈变硬趋势, 食味品质总体变劣。 相似文献
119.
120.
O. E. Ommen A. Donnelly S. Vanhoutvin M. van Oijen R. Manderscheid 《European Journal of Agronomy》1999,10(3-4):197-203
Spring wheat cv. Minaret was grown in open-top chambers at four sites across Europe. The effect of different treatments (CO2 enrichment, O3 fumigation, drought stress and temperature) on the chlorophyll content of the flag leaf was investigated using the MINOLTA SPAD-502 meter. Under optimum growth conditions the maximum chlorophyll content, which was reached at anthesis, was consistent among the sites ranging from 460 to 500 mg chlorophyll m−2. No significant effect of elevated CO2 or O3 was observed at anthesis. Leaf senescence, indicated by the chlorophyll breakdown after anthesis, was relatively constant in the control chambers. Under control conditions, thermal time until 50% chlorophyll loss was reached was 600°C day. Elevated CO2 caused a faster decline in chlorophyll content (thermal time until 50% chlorophyll loss was reduced to 500–580°C day) indicating a faster rate of plant development at two experimental sites. The effect of ozone on chlorophyll content depended on the time and dose of O3 exposure. During grain filling, high O3 concentrations induced premature senescence of the flag leaves (up to −130°C day). This deleterious effect was mitigated by elevated CO2. Drought stress led to faster chlorophyll breakdown irrespective of CO2 treatment. 相似文献