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1.
四种生态型芦苇叶片结构的研究 总被引:5,自引:0,他引:5
The leaf anatomy and uhrastructure of the vascular bundle sheath cells of four ecotypes of reed (Phragmites communis Trin. ) were observed with light and electron microscope. The four ecotypes were the swamp reed, dune reed, heavy salt meadow reed and the light salt meadow reed. It was shown that the intracellular content of the vascular bundle sheath cells of the swamp reed was lower than that of the dune reed; that of the heavy salt meadow reed was between that of the former two reeds and that of the light salt meadow reed and that of the light salt meadow reed was similar to the dune reed. The chloroplasts in the swamp reed were round-shaped with poorly developed grana. Starch grains were not visualized. The uhrastructure of their chloroplasts were similar to those in the typical C3 plants as wheat. By contrast, the chloroplasts in the vascular bundle cells of the dune reed were elliptical with their structure similar to that of the typical C4 plants as maize. These chloroplasts contained some poorly developed grana thykloid. The chloroplasts of the vascular bundle sheath cells in the heavy salt meadow reed were similar to those seen in the dune reed, however, those in the light salt meadow reed appeared to be beth round .and elliptical in shape. The above results suggested a great habitat variation did occur among the four ecotypes of reed in which these exists an obvious evolutional trend from C3 to C4 plants. 相似文献
2.
四种生态型芦苇叶片结构的研究 总被引:12,自引:0,他引:12
采用光学显微镜和电子显微镜对4种生态型芦苇(PhragmitescommunisTrin.)叶解剖结构及叶脉维管束鞘细胞超微结构进行了观察研究。结果表明,沼泽芦苇维管束鞘细胞内含物较少,维管束鞘细胞叶绿体呈近圆形,超微结构与典型C3植物小麦鞘细胞的相似,基粒发育退化,不含淀粉粒;沙丘芦苇鞘细胞内含物较多,鞘细胞叶绿体呈近椭圆形,超微结构与典型C4植物玉米的相似,具有不发达的基粒;重度盐化草甸芦苇鞘细胞内含物则较沼泽芦苇多,而较沙丘芦苇少,鞘细胞叶绿体形态、超微结构与沙丘芦苇相似;轻度盐化草甸芦苇鞘细胞内含物与沙丘芦苇相似,但是,其鞘细胞含有与沼泽芦苇鞘细胞内叶绿体形态相似的近圆形以及与沙丘芦苇和重度盐化草甸芦苇鞘细胞内形态相似的近椭圆形两种形态的叶绿体。表明生长在同一地区不同环境中的4种生态型芦苇的光合结构发生了深刻的变异,表现出从C3向C4进化的明显趋势。 相似文献
3.
A Remarkable New Leaf Type With Unusual Photosynthetic Tissue in a Central Asiatic Genus of Chenopodiaceae 总被引:7,自引:0,他引:7
Abstract: From the hygrohalophyte Borszczowia aralocaspica Bunge (Chenopodiaceae), a new leaf type with 1-layered chlorenchyma is described as "borszczovoid" and compared with other leaf types in subfamily Salsoloideae. The chlorenchyma is suspected to represent a unique C4 type. Evidence is cited from anatomical studies and documented by micrographs and Carbon isotope determinations (ä13 C values). The 1-layered photosynthetic tissue combines all essential anatomical characters of a 2-layered chlorenchyma of regular C4 plants and is in intimate contact with concentrically arranged peripheral bundles. The ä13 C values are − 13.03 ‰ from young stems and − 13.78 ‰ from leaves. The results are discussed in the anatomical, physiological and taxonomic framework. In addition, from distantly-related Suaeda species of section Conosperma the conospermoid leaf type is re-described. It is characterized by typical palisade and Kranz layers and differs from the C4 suaedoid type by an external water-storaging hypodermis and an arrangement of Kranz cells reminiscent of the atriplicoid type from subfamily Chenopodioideae. From eight other species of Chenopodiaceae ä13 C values are given for the first time. 相似文献
4.
Differences in leaf interveinal distances, chloroplasts distribution in bundle sheath cells (BSC) and activities of C4 photosynthetic enzymes in the leaves of three ecotypes of Phragmites communis Trinius, namely swamp reed (SR), heavy salt meadow reed (HSMR) and dune reed (DR), occurring in the desert region of northwest
China were investigated. The two terrestrial ecotypes, DR and HSMR, had denser vascular system, more and longer BSC chloroplasts
and higher capacity of CO2 concentrating mechanism of NAD-ME subtype as compared with the SR ecotype. The enhanced NADP-ME pathway in the HSMR might
contribute to its adaptation to the salinity habitat. 相似文献
5.
Population differences in water-use efficiency of Eucalyptus microtheca seedlings under different watering regimes 总被引:3,自引:0,他引:3
Chunyang Li 《Physiologia plantarum》2000,108(2):134-139
Gas exchange, water-use efficiency (WUE), carbon isotope composition ( Δ 13 C) and growth traits were compared among 5 populations of Eucalyptus microtheca F. Muell. Seedlings grown from seed collected across the natural distribution of the species were maintained under water-stressed and well-watered conditions. Gas exchange was measured in terms of net photosynthesis (A) and transpiration (E); WUE was measured in terms of instantaneous water-use efficiency (WUEi ) and transpiration efficiency (WUET ); growth traits were measured in terms of total biomass (TB), root/shoot ratio (RS), and specific leaf area density (DEN). Significant differences in all traits were detected among the populations. Overall population variation was 1.68–2.50 and 1.48–2.26 μmol CO2 uptake per mmol H2 O transpired (WUEi ), 1.97–3.04 and 1.64–2.36 g dry matter accumulation per kg water transpired (WUET ), and Δ 13 C was −28.81 to −26.75‰ and −30.56 to −30.04‰ under the water-stressed and well-watered conditions, respectively. In addition, WUEi , WUET and Δ 13 C were significantly correlated with A, E, RS, DEN and TB. The study indicated that measurement of WUE may be a useful trait for selecting genotypes with improved drought adaptation and biomass productivity under different environmental conditions. 相似文献
6.
J. E. Ciancio † M. A. Pascual ‡ F. Botto § M. Amaya-Santi S. O'Neal ¶ C. Riva Rossi O. Iribarne § 《Journal of fish biology》2008,72(7):1708-1719
In the present study, profiles of stable isotope composition were characterized for two species with partially migratory populations in rivers along the latitudinal gradient of Patagonia, brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss . The effects of factors ( e.g. ontogeny of fishes, location, species and fasting) that may influence the stable isotope analysis (SIA) were evaluated, as was SIA evaluated as a tool to assign individual fish to their corresponding ecotype. Anadromous fishes exhibited enriched δ15 N (15·2 ± 1·0‰; mean ± s . d .) and δ13 C (−19·2 ± 1·3‰) relative to resident fishes'δ15 N (8·8 ± 1·1‰) and δ13 C (−23·2 ± 2·5‰). For both species, the difference in δ15 N was larger between resident (range 6·8–10·7‰) and anadromous (range 14·3–17·8‰) fishes than that in δ13 C. Values of δ13 C, while not as dramatically contrasting in rainbow trout, provided a powerful anadromy marker for brown trout in the region. Increases were found in both δ15 N and δ13 C during the spawning migration of anadromous rainbow trout, most likely due to fasting. Differences in stable isotopes between location, size and species were found, suggesting different stable isotopes base levels in freshwater environments and different trophic levels and feeding location of anadromous populations. The SIA was demonstrated as a powerful tool for ecotype discrimination in Patagonian Rivers, overriding any effect of sampling location, size or species. 相似文献
7.
四种生态型芦苇叶中离子分布对生境的生理适应 总被引:9,自引:0,他引:9
采用X射线微区分析技术 ,测定了 4种生态型芦苇 (Phragmitesaustralis (CaV .)Trin .exSteud .)叶的表皮泡状细胞、叶肉细胞和叶脉维管束鞘细胞离子的含量。结果表明 :沼泽芦苇的鞘细胞内 ,K 、Na 、Ca2 、Mg2 和Cl-分布均较叶肉细胞和泡状细胞高。沙丘芦苇的泡状细胞中Ca2 分布较叶肉细胞和鞘细胞高 ,而Mg2 在其叶肉细胞 ,以及K 、Na 和Cl- 在其鞘细胞内分布均较高。在轻度盐化草甸芦苇的叶肉细胞内分布较多的Na 和Mg2 ,而在鞘细胞内K 、Ca2 和Cl- 的分布均较叶肉细胞和泡状细胞为高。重度盐化草甸芦苇的泡状细胞内Na 和Mg2 的分布较多 ;同样 ,在叶肉细胞中K 、Ca2 和Cl- 的分布也较多。最后 ,讨论了上述各种离子在不同生态型芦苇叶内分布的状况 ,以及与其环境适应的生理意义。 相似文献
8.
采用X射线微区分析技术,测定了4种生态型芦苇(Phragmites australis (CaV.) Trin. exSteud.)叶的表皮泡状细胞、叶肉细胞和叶脉维管束鞘细胞离子的含量.结果表明:沼泽芦苇的鞘细胞内,K+、Na+、Ca2+、Mg2+和Cl-分布均较叶肉细胞和泡状细胞高.沙丘芦苇的泡状细胞中Ca2+分布较叶肉细胞和鞘细胞高,而Mg2+在其叶肉细胞,以及K+、Na+和Cl-在其鞘细胞内分布均较高.在轻度盐化草甸芦苇的叶肉细胞内分布较多的Na+和Mg2+,而在鞘细胞内K+、Ca2+ 和Cl-的分布均较叶肉细胞和泡状细胞为高.重度盐化草甸芦苇的泡状细胞内Na+和Mg2+的分布较多;同样,在叶肉细胞中K+、Ca2+和Cl-的分布也较多.最后,讨论了上述各种离子在不同生态型芦苇叶内分布的状况, 以及与其环境适应的生理意义. 相似文献
9.
Christopher H. House Victoria J. Orphan Kendra A. Turk Burt Thomas Annelie Pernthaler Jennifer M. Vrentas Samantha B. Joye 《Environmental microbiology》2009,11(9):2207-2215
To assess and study the heterogeneity of δ13 C values for seep microorganisms of the Eel River Basin, we studied two principally different sample sets: sediments from push cores and artificial surfaces colonized over a 14 month in situ incubation. In a single sediment core, the δ13 C compositions of methane seep-associated microorganisms were measured and the relative activity of several metabolisms was determined using radiotracers. We observed a large range of archaeal δ13 C values (> 50‰) in this microbial community. The δ13 C of ANME-1 rods ranged from −24‰ to −87‰. The δ13 C of ANME-2 sarcina ranged from −18‰ to −75‰. Initial measurements of shell aggregates were as heavy as −19.5‰ with none observed to be lighter than −57‰. Subsequent measurements on shell aggregates trended lighter reaching values as 13 C-depleted as −73‰. The observed isotopic trends found for mixed aggregates were similar to those found for shell aggregates in that the initial measurements were often enriched and the subsequent analyses were more 13 C-depleted (with values as light as −56‰). The isotopic heterogeneity and trends observed within taxonomic groups suggest that ANME-1 and ANME-2 sarcina are capable of both methanogenesis and methanotrophy. In situ microbial growth was investigated by incubating a series of slides and silicon (Si) wafers for 14 months in seep sediment. The experiment showed ubiquitous growth of bacterial filaments (mean δ13 C = −38 ± 3‰), suggesting that this bacterial morphotype was capable of rapid colonization and growth. 相似文献
10.
Inferences about the evidence of life recorded in organic compounds within the Earth's ancient rocks have depended on 13 C contents low enough to be characteristic of biological debris produced by the well-known CO2 fixation pathway, the Calvin cycle. 'Atypically' high values have been attributed to isotopic alteration of sedimentary organic carbon by thermal metamorphism. We examined the possibility that organic carbon characterized by a relatively high 13 C content could have arisen biologically from recently discovered autotrophic pathways. We focused on the green non-sulphur bacterium Chloroflexus aurantiacus that uses the 3-hydroxypropionate pathway for inorganic carbon fixation and is geologically significant as it forms modern mat communities analogous to stromatolites. Organic matter in mats constructed by Chloroflexus spp. alone had relatively high 13 C contents (−14.9‰) and lipids diagnostic of Chloroflexus that were also isotopically heavy (−8.9‰ to −18.5‰). Organic matter in mats constructed by Chloroflexus in conjunction with cyanobacteria had a more typical Calvin cycle signature (−23.5‰). However, lipids diagnostic of Chloroflexus were isotopically enriched (−15.1‰ to −24.1‰) relative to lipids typical of cyanobacteria (−33.9‰ to −36.3‰). This suggests that, in mats formed by both cyanobacteria and Chloroflexus , autotrophy must have a greater effect on Chloroflexus carbon metabolism than the photoheterotrophic consumption of cyanobacterial photosynthate. Chloroflexus cell components were also selectively preserved. Hence, Chloroflexus autotrophy and selective preservation of its products constitute one purely biological mechanism by which isotopically heavy organic carbon could have been introduced into important Precambrian geological features. 相似文献
11.
Carbon-Isotope Ratios and Photosynthetic Pathways in the Neotropical Family Rapateaceae 总被引:1,自引:0,他引:1
Abstract: The Rapateaceae is a small, mainly Neotropical family of terrestrial or occasionally epiphytic herbs that grow on mesic, nutrient-poor sites. Some recent studies suggest that the Rapateaceae may be closely related to the Bromeliaceae, one of the major families containing CAM plants. To investigate the photosynthetic pathway in Rapateaceae, the plant carbon-isotope ratio (δ13 C) was determined for samples from dried herbarium specimens for 85 of the approximately 100 species in the family. The δ13 C values ranged from - 37.7 to - 19.8 ‰. Most Rapateaceae showed δ13 C values typical of C3 plants. However, six species ( Kunhardtia rhodantha Maguire, Marahuacaea schomburgkii (Maguire) Maguire, Saxofridericia compressa Maguire, Stegolepis grandis Maguire, St. guianensis Klotzsch ex Körn. and St. squarrosa Maguire) showed δ13 C values less negative than - 23 ‰, i.e., at the higher end of the range for C3 plants and at the lower end of the distribution for plants exhibiting CAM. The δ13 C values became significantly less negative with increasing altitude (regression analysis indicating a change from about - 30.7 ‰ at sea level to - 22.5 ‰ at 2500 m). Although other environmental factors and the type of tissue analysed may also influence δ13 C values, these results suggest that some Rapateaceae may be capable of performing CAM. Further studies, including measurements of diel gas exchange patterns and leaf organic-acid fluctuations, would be needed to demonstrate CAM in Rapateaceae unequivocally, but living material of many of these enigmatic plants is difficult to obtain. 相似文献
12.
Different carbon support for respiration and secondary production in unproductive lakes 总被引:1,自引:0,他引:1
Jan Karlsson 《Oikos》2007,116(10):1691-1696
This study investigates the allocation of allochthonous organic carbon (AlloOC) to pelagic respiration and biomass production in unproductive lakes. Metabolic process rates and stable isotopic composition (δ13 C) of crustacean zooplankton and respired CO2 were measured in the epilimnion of 13 forest lakes in northern Sweden. The δ13 C of zooplankton was low (−31.2 to −38.0‰) compared to that of respired CO2 (−28.4 to −30.6‰), implying that the relative importance of AlloOC was lower for zooplankton (ca 40%) than for respiration (ca 80%). Combining δ13 C and carbon flux data revealed that a large amount of metabolized AlloOC was lost in respiration, compared to the amount transferred to zooplankton (<3%). Thus, despite large respiratory losses, AlloOC was still important for zooplankton growth, implying a high supply of AlloOC in comparison to phytoplankton generated organic carbon in the lakes. 相似文献
13.
We evaluated diurnal and seasonal patterns of carbon isotope composition of leaf dark-respired CO2 ( δ 13 Cl ) in the C3 perennial shrub velvet mesquite ( Prosopis velutina ) across flood plain and upland savanna ecosystems in the south-western USA. δ 13 Cl of darkened leaves increased to maximum values late during daytime periods and declined gradually over night-time periods to minimum values at pre-dawn. The magnitude of the diurnal shift in δ 13 Cl was strongly influenced by seasonal and habitat-related differences in soil water availability and leaf surface vapour pressure deficit. δ 13 Cl and the cumulative flux-weighted δ 13 C value of photosynthates were positively correlated, suggesting that progressive 13 C enrichment of the CO2 evolved by darkened leaves during the daytime mainly resulted from short-term changes in photosynthetic 13 C discrimination and associated shifts in the δ 13 C signature of primary respiratory substrates. The 13 C enrichment of dark-respired CO2 relative to photosynthates across habitats and seasons was 4 to 6‰ at the end of the daytime period (1800 h), but progressively declined to 0‰ by pre-dawn (0300 h). The origin of night-time and daytime variations in δ 13 Cl is discussed in terms of the carbon source(s) feeding respiration and the drought-induced changes in carbon metabolism. 相似文献
14.
A. KOHZU T. YOSHIOKA T. ANDO M. TAKAHASHI K. KOBA & E. WADA 《The New phytologist》1999,144(2):323-330
The natural abundance of 13 C and 15 N was measured in basidiocarps of at least 115 species in 88 genera of ectomycorrhizal, wood-decomposing and litter-decomposing fungi from Japan and Malaysia. The natural abundance of 13 C and 15 N was also measured in leaves, litter, soil and wood from three different sites. 15 N and 13 C were enriched in ectomycorrhizal and wood-decomposing fungi, respectively, relative to their substrates. Ectomycorrhizal and wood-decomposing fungi could be distinguished on the basis of their δ13 C and δ15 N signatures. Although there was high variability in the isotopic composition of fungi, the following isotope- enrichment factors (ε, mean±SD) of the fungi relative to substrates were observed:
εectomycorrhizal fungi/litter = 6.1±0.4‰15 N
εectomycorrhizal fungi/wood = 1.4±0.8‰13 C
εwood-decomposing fungi/wood = −0.6±0.7‰15 N
εwood-decomposing fungi/wood = 3.5±0.9‰13 C
The basis of isotope fractionation in C metabolism from wood to wood-decomposing fungus is discussed. 相似文献
ε
ε
ε
ε
The basis of isotope fractionation in C metabolism from wood to wood-decomposing fungus is discussed. 相似文献
15.
It has been suggested previously that Japanese larch ( Larix kaempferi ) exhibits characteristics of C4 photosynthesis. To further evaluate this suggestion, stable carbon isotope ratios were determined for leaf and bark tissue of Larix gmelini, L. kaempferi, L. laricina, L. Iyallii, L. occidentalis , and L. sibirica. All δ13 C values were more negative than –22‰. Short-term labeling with 14 CO2 showed that phosphoglyceric acid and other phosphorylated compounds were the first products of photosynthesis in L. sibirica. Both of these results strongly suggest that the initial fixation of atmospheric CO2 in these six Larix species is accomplished solely via the C3 photosynthetic pathway. 相似文献
16.
Stable isotopes of carbon and nitrogen as indicators of diet and trophic structure of the fish community in a shallow hypereutrophic lake 总被引:5,自引:1,他引:4
Stable carbon (δ13 C) and nitrogen (δ15 N) isotopes were employed to elucidate energy flows and trophic interactions in Lake Apopka, a hypereutrophic lake in central Florida, U.S.A. Isotope compositions of lake biota ranged from −27·1 to −3·0‰ for δ13 C, and from 3·7 to 13·9‰ for δ15 N. The food web was based primarily on plankton production with diatoms, Microcystis and zooplankton dominating the diet of fish. Carbon isotope evidence showed that pico- and nano-phytoplankton were not a direct carbon source for fish, but were important to zooplankton. δ15 N mass balance estimates indicated that planktivorous fish obtained 48–85% of their diets from zooplankton. The ∼3‰ range of δ15 N in gizzard shad reflected increasing dependence on zooplankton as fish grew whereas the positive relationship between total length and δ15 N of largemouth bass reflected increasing predation on larger planktivorous fish with growth. The broad ranges of δ13 C (−25·9 to −9·5‰) and δ15 N (5·8 to 14·4‰) of blue tilapia were indicators of diet diversity. Two presumed omnivores (brown bullhead and white catfish) and piscivores (black crappie, largemouth bass and Florida gar) were found to depend on planktivorous fish. However, stable isotope data revealed no trophic links between blue tilapia, an abundant fish in the near-shore area, and piscivores. 相似文献
17.
Guoan Wang Jiamao Han Liping Zhou Xiaogang Xiong Zhenhai Wu 《Physiologia plantarum》2005,125(1):74-81
Carbon isotope ratio of leaf dry matter, δ 13 C, was measured on species occurring within Baiyin desert community, consisting of valley, slope and ridge microhabitats, and within Shandan desert community, consisting of Gobi desert and seasonal flooded creek microhabitats, in Northwest China. δ 13 C of C3 species increased with a decrease in soil water availability, suggesting that water-use efficiency (WUE) increased with decreasing soil moisture, whereas for all C4 species, δ 13 C tended to decrease with decreasing soil water availability, suggesting that WUE also increased with decreasing soil moisture. Above results indicated that water-use pattern was conservative under drought for C4 and C3 plants. In this present study, C4 species' occurrences within different microhabitats were investigated and C4 plants were observed to be absent and/or scarce within relatively lower soil moisture microhabitats, whereas they occurred and/or even had a high abundance within relatively higher soil moisture microhabitats, suggesting limited moisture available was a key factor of limiting C4 distribution in arid region of Northwest China. 相似文献
18.
Heidi Porras-Peters David Aurioles-Gamboa Victor Hugo Cruz-Escalona † Paul L. Koch ‡ 《Marine Mammal Science》2008,24(3):554-576
Stable isotope and scat analyses were used in concert to determine trophic level and dietary overlap among California sea lions from different rookeries in the Gulf of California. Isotopic analysis of the fur of sea lion pups revealed differences in δ15 N and δ13 C values among rookeries during the breeding season. Mean δ15 N and δ13 C values varied from 20.2‰ to 22.4‰ and from −15.4‰ to −14.0‰, respectively. The pattern of differences among rookeries was similar between years in most cases. Isotopic variations among rookeries were associated with differences in prey consumption. There was a significant correlation between δ15 N value and trophic level, as determined by scat analysis. Joint application of isotopic and scat analyses allowed us to identify how the feeding habits of sea lions vary with location. Our results suggest the presence of spatial structure in available prey as well as the localized use of prey by sea lions across the Gulf of California. 相似文献
19.
Abstract: Over 60 Salsola species of Chenopodiaceae from South Africa were studied for their photosynthesis type, using δ13 C analysis and light microscopy of leaf anatomy. These species cover about 70 % of the total list of Southern African Salsola species and grow naturally in South and Southwest African desert regions. All species are shrubby forms and belong to the single subsection Caroxylon. Only C4 photosynthesis was found in the Salsola species determined with 13 C/12 C carbon isotope discrimination values that ranged from - 11.04 to - 14.03 % (PDB), plus the presence of a Kranz type assimilation tissue anatomy. The apparent absence of C3 in Salsola in South and Southwest Africa and the known presence of C3 and C3 - C4 intermediate photosynthesis in Caroxylon, Salsola species in Asia strongly indicate that the genus Salsola originated in Asia and later migrated to South Africa. 相似文献
20.
M. DURANCEAU J. GHASHGHAIE F. BADECK E. DELEENS & G. CORNIC 《Plant, cell & environment》1999,22(5):515-523
The variations in δ 13 C in both leaf carbohydrates (starch and sucrose) and CO2 respired in the dark from the cotyledonary leaves of Phaseolus vulgaris L. were investigated during a progressive drought. As expected, sucrose and starch became heavier (enriched in 13 C) with decreasing stomatal conductance and decreasing p i / p a during the first half (15 d) of the dehydration cycle. Thereafter, when stomata remained closed and leaf net photosynthesis was near zero, the tendency was reversed: the carbohydrates became lighter (depleted in 13 C). This may be explained by increased p i / p a but other possible explanations are also discussed. Interestingly, the variations in δ 13 C of CO2 respired in the dark were correlated with those of sucrose for both well-watered and dehydrated plants. A linear relationship was obtained between δ 13 C of CO2 respired in the dark and sucrose, respired CO2 always being enriched in 13 C compared with sucrose by ≈ 6‰. The whole leaf organic matter was depleted in 13 C compared with leaf carbohydrates by at least 1‰. These results suggest that: (i) a discrimination by ≈ 6‰ occurs during dark respiration processes releasing 13 C-enriched CO2 ; and that (ii) this leads to 13 C depletion in the remaining leaf material. 相似文献