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1.
《山地科学学报》2017,(10)
Phenotypic plasticity and/or pollinatormediated selection may be responsible for the changes in floral traits of plants when they are forced to live in new conditions. Although the two events could be independent, we hypothesized that phenotypic plasticity in floral traits might help to coordinate plant-pollinator interactions and enhance plant reproductive success in changing habitats. To test this hypothesis, we investigated floral traits and pollination on three natural populations of a lousewort(Pedicularis siphonantha) ranging at different elevations, as well as two downward transplanted populations in Shangeri-La County and Deqin County, northwest Yunnan, China. The results indicated that floral traits, i.e. phenology, longevity,display size, corolla tube length and pollen production differed significantly among populations. Moreover,or the two transplanted populations, floral traits diverged from their original populations, but converged to their host populations. Although the phenotypic plasticity in floral traits might be a rapid response to abiotic factor such as warmer environment, the changes in floral traits were found to be well adapted to pollination environment of the host population. Compared with plants of their original habitats in higher elevation, the transplanted individuals advanced flowering time, shortened flower longevity, reduced floral display size and pollen production, received higher visiting frequency and yielded more seeds. These findings suggested that phenotypic plasticity of floral traits might help plants adjust their resource allocation strategy between preand post-pollination stages in response to harsh or temperate conditions, which might correspondingly meet a pollinator-poor or hyphen rich environment.This would be beneficial for the widely-distributed species to adapt to various environmental changes. 相似文献
2.
《山地科学学报》2016,(12)
Paeonia delavayi is a wild tree peony species endemic to high-altitude regions in southwestern China.Recent agricultural land expansion,however,not only causes its dwindling population size,but also poses a severe threat to its long-term persistence.Since our knowledge of the reproductive biology of P.delavayi is very limited,and some management misconceptions have further exacerbated the already worrisome situation,the aim of the present study is to provide some scientific evidence regarding habitat preference and breeding system of P.delavayi,and to help correct some management misconceptions.Specifically,morphological traits of P.delavayi populations growing in two different habitats(i.e.,the open area versus forest understory),including basal stem diameter,plant height and flower numbers per plant,were measured and compared with each other.A range of floral manipulation experiments was further conducted to study the extent of self-compatibility and pollen limitation.The results showed that P.delavayi preferred the open habitat over forest understory as it generally grew bigger with thickerstems,and produced a higher number of flowers in the former habitat.Therefore,the open habitat should receive immediate priority for conservation action instead of being converted to agricultural land;also,P.delavayi is pollen limited,as evidenced by the fact that experimental flowers receiving supplemental non-self pollen generally displayed elevated seed production than flowers subjected to other treatments(e.g.,non-supplemental self pollen,non-supplemental non-self pollen and supplemental self pollen),which is consistent with reported observations that alpine plants are more likely to be pollen-limited than lowland plants.We suggest that human intervention might be necessary to guarantee the long-term persistence of P.delavayi as harsh alpine environment,intense competition for pollinators and different anthropogenic perturbations co-limit its reproductive success. 相似文献
3.
Paeonia delavayi is a wild tree peony species endemic to high-altitude regions in southwestern China. Recent agricultural land expansion, however, not only causes its dwindling population size, but also poses a severe threat to its long-term persistence. Since our knowledge of the reproductive biology of P. delavayi is very limited, and some management misconceptions have further exacerbated the already worrisome situation, the aim of the present study is to provide some scientific evidence regarding habitat preference and breeding system of P. delavayi, and to help correct some management misconceptions. Specifically, morphological traits of P. delavayi populations growing in two different habitats (i.e., the open area versus forest understory), including basal stem diameter, plant height and flower numbers per plant, were measured and compared with each other. A range of floral manipulation experiments was further conducted to study the extent of self-compatibility and pollen limitation. The results showed that P. delavayi preferred the open habitat over forest understory as it generally grew bigger with thicker stems, and produced a higher number of flowers in the former habitat. Therefore, the open habitat should receive immediate priority for conservation action instead of being converted to agricultural land; also, P. delavayi is pollen limited, as evidenced by the fact that experimental flowers receiving supplemental non-self pollen generally displayed elevated seed production than flowers subjected to other treatments (e.g., non-supplemental self pollen, non-supplemental non-self pollen and supplemental self pollen), which is consistent with reported observations that alpine plants are more likely to be pollen-limited than lowland plants. We suggest that human intervention might be necessary to guarantee the long-term persistence of P. delavayi as harsh alpine environment, intense competition for pollinators and different anthropogenic perturbations co-limit its reproductive success. 相似文献
4.
Middle and Late Permian palynoflora in Tianshan Township,southeast of Bogda Mountain,Xinjiang, China
The Permian is one of the most important periods during which the vegetative earth witnessed the transition from icehouse to greenhouse climate and the global environment changes. Organisms on the planet en-countered great challenge and the demise of swamp caused the extinction of arborescent lycopods and the rising of Mesophytic plants accomplished the floral transition from the Paleophytic to Mesophytic vegetation. In order to depict the climatic changes and floral succession in the middle and high latitudes of the North Hemisphere, palynological investigation was engaged, and 40 samples collected from the uppermost of Taerlang Formation, Hongyanchi Formation and Quanzijie Formation in the Tianshan Town, Turpan-Hami Basin, eastern Xinjiang, China. The result shows that the palynoflora in the studied area is composed of 50 species of 33 genera, domi-nated by disaccites and striatiti gymnosperm pollen, and characterized by diverse Protohaploxypinus, Hamia-pollenites, Alisporites and Klausipollenites. It is quite similar to those Middle and Late Permian palynological as-semblages reported in the Dalongkou section and other localities in southern margin of Junggar Basin, and aged at Middle and Late Permian. The diversity of typical Angara and sub-Angara pollen, such as Falcisporites, Alisporites, Protohaploxypinus, Vittatina, Lunatisporites, Hamiapollenites, etc. indicates that the studied palyno-flora belonged to the sub-Angara phytoprovince, while the presence of Lueckisporites virkkiae implied Euramerica pollen intruded northward sometimes. The paleoclimate of the studied area might be warm and humid with fluc-tuated dry seasons during the late Guadalupian and early Lopingian time. 相似文献
5.
Reservoir impoundment changes original fluvial habitats into lentic environments. Fish species adapted to lentic habitats may take the advantage of such habitat changes and show typical life history traits might facilitate the population increase. Siniperca kneri rarely occurred in fishery landing in the Three Gorges Reservoir(TGR) area before its impoundment in 2003, but it is now a dominant species. In this study, a total of 438 females of S. kneri were collected monthly during September 2012 through January2014 using gill nets in the TGR. The age, growth, and reproductive biology were then investigated, and compared with other S. kneri populations. The standard length at age 1 was 149.9 mm in the TGR, which is larger than the three compared populations(i.e., Sandaohe Reservoir, Xinfengjiang Reservoir, and North River), but smaller than one(the Guishi Reservoir). The youngest mature female in the TGR was age 1,which is younger than that of the two compared populations(i.e., Xinfengjiang Reservoir and the North River). The relative fecundity in the TGR was 140 eggs/g, which is higher than that of the only available compared population(Xinfengjiang Reservoir, 96 eggs/g). Our results demonstrated that S. kneri in the TGR tended to have faster growth in the first year, a younger age at first maturation, and higher reproductive ef fort.We suggest that such opportunistic-tended life history traits might facilitate rapid increase of the population. 相似文献
6.
Over the past few decades, extreme changes have occurred in the characters of exploited fish populations. The majority of these changes have affected the growth traits of fish life history, which include a smaller size-at-age, an earlier age-at-maturation and among others. Currently, the causes of these life history traits changes still require systematic analyses and empirical studies. The explanations that have been cited are merely expressed in terms of fish phenotypic adaptation. It has been claimed that the original traits of fish can be recovered once the intensity of exploitation of the fish is controlled. Sustained environmental and fishing pressure will change the life history traits of most fish species, so the fish individual’s traits are still in small size-at-age and at earlier age-at-maturation in exploited fish populations. In this paper, we expressed our view of points that fishing gear has imposed selectiv-ity on fish populations and individuals as various other environmental factors have done and such changes are unrecoverable. Ac-cording to the existing tend of exploited fish individual’s life history traits, we suggested further researches in this field and provided better methods of fishery management and thereby fishery resources protection than those available early. 相似文献
7.
二穗短柄草是一种理想的研究温带禾谷类植物和牧草的模式植物。对源于以色列4个不同地区(群体)90个生态型二穗短柄草的物候期和农艺性状差异及其相关性进行了研究。结果表明,在贵州自然气候条件下,以色列二穗短柄草生态型间和群体间在生长期、各农艺性状表现均有所不同,方差分析呈极显著差异(P<0.0001);各群体生长期平均值的顺序为:Tibigha相似文献
8.
The paper describes the sedimentary features and biostratigraphy of the transitional Jurassic to Cretaceous deposits in the continental basins of Priamurie formed after the collision between the Siberian and North China blocks. In Upper Priamurie, the collision occurred in the late Early Jurassic as dated by the emplacement of the post-collisional granites (191Ma) . While in Lower Priamurie and West Priokhotie it could take place in the late Middle Jurassic on the basis of fossil evidence from an accretionary turbidite complex. This event reflected the environmental change from coastal-marine to alluvial plains, often boggy, where coals accumulated. The environmental change is in harmony with that of biota. Systematic study of floral and spores/pollen assemblages, particularly in the sections of interbedded marine and non-marine deposits, makes clear the chronostratigraphic succession of floral associations and shows the possibility of their application for subdivision and correlation of the continental deposits of Priamurie. The coastal-marine environment of the residual post-collisional sublatitudinal basins in the western part of Priamurie (Upper Amur and Dep basins) was replaced by the continental in the late Middle Jurassic and in the eastern part in the Berriasian-Valanginian ( Torom Basin) . Similar environmental change commenced in the submeridional rift basins: the Bureya Basin in the Callovian and the Partizansk Basin in the Hauterivian. Changes in ecosystems occurred frequently during theMiddle Jurassic-Neocomian, but the most substantial changes took place in the late Middle Jurassic and in the end of Late Jurassic. 相似文献
9.
Land animals as well as all organisms in ocean synthesize sulfated polysaccharides. Fungi split from animals about 1.5 billion years ago. As fungi make the evolutionary journey from ocean to land, the biggest changes in their living environment may be a sharp decrease in salt concentration. It is established that sulfated polysaccharides interact with hundreds of signaling molecules and facilitate many signaling transduction pathways, including fibroblast growth factor(FGF) and FGF receptor signaling pathway. The disappearance of sulfated polysaccharides in fungi and plants on land might indicate that polysaccharides without sulfation might be sufficient in facilitating protein ligand/receptor interactions in low salinity land. Recently, it was reported that plants on land start to synthesize sulfated polysaccharides in high salt environment, suggesting that fungi might be able to do the same when exposed in such environment. Interestingly, Cordyceps, a fungus habituating inside caterpillar body, is the most valued traditional Chinese Medicine. One of the important pharmaceutical active ingredients in Cordyceps is polysaccharides. Therefore, we hypothesize that the salty environment inside caterpillar body might allow the fungi to synthesize sulfated polysaccharides. To test the hypothesis, we isolated polysaccharides from both lava and sporophore of wild Cordyceps and also from Cordyceps militaris cultured without or with added salts. We then measured the polysaccharide activity using a FGF2/FGFR1 c signaling-dependent Ba F3 cell proliferation assay and found that polysaccharides isolated from wild Cordyceps activated FGF2/FGFR signaling, indicating that the polysaccharides synthesized by wild Cordyceps are indeed different from those by the cultured mycelium. 相似文献
10.
References： 《东北亚地学研究》2007,10(1):6-10
The changes of taxonomical composition of the Late Jurassic- Early Cretaceous palynofloras are revealed, in the upper stream of Bureya River in Bureya Basin. The palynofloras are dominated as follows： the Berriasian one by ferns （Cyatheaceae, Dicksoniaceae, Osmundaceae）, Classopollis and bisaccate pollen; the Valanginiar-Hauterivian one by ferns （Cyatheaceae, Dicksoniaceae）, Ginkgocycadophytus and bisaccate pollen; the Barremian one by ferns （Cyatheaceae, Dicksoniaceae）; the Aptian one by ferns （Cyatheaceae, Dicksoniaceae, Gleicheniaceae） and Ginkgocycadophytus; and the Albian one by ferns （Schizaeaceae） and bisaccate pollen. In the Albian the floral diversity raises with the angiosperms appearing. 相似文献
11.
The changes of taxonomical composition of the Late Jurassic-Early Cretaceous palynofloras are revealed,in the upper stream of Bureya River in Bureya Basin.The palynofloras are dominated as follows:the Berriasian one by ferns (Cyatheaceae,Dicksoniaceae,Osmundaceae), Classopollis and bisaccate pollen;the Valanginian-Hauterivian one by ferns (Cyatheaceae,Dicksoniaceae), Ginkgocycadophytus and bisaccate pollen;the Barremian one by ferns(Cyatheaceae,Dieksoniaceae);the Aptian one by ferns(Cyatheaceae,Dieksoniaceae,Gleicheniaceae)and Ginkgocycadophytus;and the Albian one by ferns(Schizaeaceae)and bisaccate pollen.In the Albian the floral diversity raises with the angiosperms appearing. 相似文献
12.
The changes of taxonomical composition of the Late Jurassic-Early Cretaceous palynofloras are revealed,in the upper stream of Bureya River in Bureya Basin.The palynofloras are dominated as follows:the Berriasian one by ferns(Cyatheaceae,Dicksoniaceae,Osmundaceae),Classopollis and bisaccate pollen;the Valanginian-Hauterivian one by ferns(Cyatheaceae,Dicksoniaceae),Ginkgocycadophytus and bisaccate pollen;the Barremian one by ferns(Cyatheaceae,Dicksoniaceae);the Aptian one by ferns(Cyatheaceae,Dicksoniaceae,Gleicheniaceae) and Ginkgocycadophytus;and the Albian one by ferns(Schizaeaceae) and bisaccate pollen.In the Albian the floral diversity raises with the angiosperms appearing. 相似文献
13.
Our research addresses questions about how micro-climate affects activity abundance of a common and widespread harvestman in an alpine ecosystem. Activity patterns of the Harvestman Mitopus morio （Fabricius, 1779） were studied along different alpine gradients in the central Norwegian Scandes. Within a nested design, we surveyed 18 alpine habitats with pitfall traps and microclimatological equipment along oceanic-continental, two elevational, and （fine-scaled） microtopographic gradients. Sites in the oceanic region of the Scandes showed generally higher abundance of M. morio than sites in the continental region. Furthermore, along the elevational gradient, middle-alpine sites showed higher abundances than low-alpine sites. These general patterns are best explained by higher humidity in the oceanic region and in the middlealpine belt. Focusing at a finer scale, i.e. one elevational level within each region, revealed partly opposing activity patterns within relatively short distances. While in the western middle-alpine belt these patterns were best explained by humidityrelated measures but now with higher activity abundance during drier conditions, in the drier eastern middle-alpine belt heat sums rather than humidity were found to be the best explanatoryvariables for the observed patterns. Hence, our results imply a pronounced different reaction of the two populations towards climatic variables that partly even contradict the previously described general pattern. Regardless whether these differences in activity abundance in M. morio are a form of phenotypic plasticity or adaptation, our findings stress the importance of detailed autecological knowledge combined with fine-scaled climatic measurements when aiming at predictions about possible future ecosystem structures and spatiotemporal phenomena. M. morio proves to be an ideal biogeographic model organism for understanding spatio-temporal responses of alpine ecosystems under modified climatic conditions. 相似文献
14.
Siberian larch (Larix sibirica Ledeb.) forests cover the largest areas in the Eurasian boreal zone, but there are insufficient data on its root system including the structure and functional traits of ectomycorrhizas (EM). The aim of this research is to find out if the morphological parameters of Larix sibirica EMs responded to the changes in elevation and main ecological factors (soil humidity, soil richness, soil acidity and habitat illumination). Using light microscopy, we studied EM diameter, root diameter, mantle width, and mantle volume share, share of tannin cells layers, EM density and EM length of Larix sibirica in two main types of plant communities along the elevation gradient at the Northern and Subpolar Urals. Differences in the environment were traced using phytoindication approach and the Ellenberg ecological scales. All the studied traits depend on the elevation and studied ecological factors. The diversity of fungal mantles is low, and the proportion of unstructured and pseudoparenchymatous mantles is high in response to the deterioration of the humidity, soil nitrogen content and acidity at higher-altitude habitats. Results of EM quantitative parameters measurements confirmed this pattern. We found a decline in the EM linear dimensions accompanied by a compensatory growth of the EM density with the raised elevation and the deterioration of environmental conditions. 相似文献
15.
Ten clonal units of Carex pseudocuraica growing in four different microhabitats (perennial flooded ditch water, perennial flooded ditch sediment, seasonal flooded
ditch sediment and perennial flooded soil) of the Sanjiang Plain, Northeast China, were collected randomly for phenotypic
plasticity analysis. Iron content, chemical and physical properties of substrates and the total Fe of nine plant modules were
measured as well. The results show that the performance of the C. pseudocuraica is affected by the microhabitat, with the greatest performance score in perennial flooded ditch water, and the lowest in
perennial flooded soil. The biomass allocation indexes indicate that much more mass is allocated to stems and roots to expand
colonization area. The distribution of the total Fe in plant modules appears as pyramids from the tip to the root, while marked
differences are observed in the distribution proportion of stems, tillering nodes and roots that are allometrically growing.
Iron transfer from substrates to the plant is mainly controlled by the substrate type. The differences of iron distribution
and transfer in the plant in different microhabitats are attributed to the iron contents of the substrates as well as the
phenotypic plasticity of the plant. 相似文献
16.
This study addressed the floral component traits and biomass allocation patterns of Gentiana hexaphylla as well as the relationships of these parameters along an elevation gradient (approximately 3700 m, 3800 m, 3900 m, and 4000 m) on the eastern Qinghai-Tibet Plateau. The plant height, floral characteristics, and biomass allocation of G. hexaphylla were measured at different altitudes after field sampling, sorting, and drying. Plant height was significantly greater at 3700 m than that at other elevations. Flower length was significantly greater at 4000 m than that at other elevations, whereas the flower length at low elevations showed no significant differences. Corolla diameter increased with altitude, although the difference was not significant between 3800 m and 3900 m. Variations in biomass accumulation, including the aboveground, photosynthetic organ, flower and belowground biomasses, showed non-linear responses to changes in altitude. The aboveground and photosynthetic organ biomasses reached their lowest values at 4000 m, whereas the belowground and flower biomass reached minimum values at 3700 m. The sexual reproductive allocation of G. hexaphylla also increased with altitude, with a maximum observed at 4000 m. These results suggest that external environmental factors and altitudinal gradients as well as the biomass accumulation and allocation of G. hexaphylla play crucial roles in plant traits and significantly affect the ability of this species to adapt to harsh environments. The decreased number of flowers observed at higher altitudes may indicate a compensatory response for the lack of pollinators at high elevations, which is also suggested by the deformed flower shapes at high altitudes. In addition, the individual plant biomass (i.e., plant size) had significantly effect on flower length and corolla diameter. Based on the organ biomass results, the optimal altitude for G. hexaphylla in the eastern Qinghai-Tibet Plateau is 3800 m, where the plant exhibits minimum propagule biomass and asexual reproductive allocation. 相似文献
17.
Rocky habitats are regarded as biodiversity hot-spots.Along with high species diversity,diverse ecological relationships can be observed in these habitats.Large groups of bird species use rocks in various ways:as perching/roosting sites,breeding or foraging habitats,information exchange sites,display arenas or as sources of minerals and water.Because of the inaccessibility of these environments,their role and importance to animals has been underestimated.We evaluated the use of rocky habitats by birds in the Tatra Mountains(49°13'N,19°57'E,Carpathians,central Europe).Rocky habitats were used by 29 bird species,eight of which used cliffs directly(i.e.for nesting,foraging or resting).The number of species recorded as using cliffs was correlated with the surface area of the cliff face.A total of 20 forms of rocky habitat use were recorded,in five behavioural categories:vocalization,foraging,perching,flight and nesting.Prevailing behaviours were flying by a rock face,circling above the face,and vocalization on a tree/shrub growing next to a rock.Rocks provide a nesting habitat for specialized petrophilic species and permit the existence of numerous ecological relations between species and habitats.The results of this study show that rocky habitats support the diversity of ecological relationships. 相似文献
18.
依据化石的层位分布和组成内容，登封二叠纪煤系地层植物群由下而上可划分为三个植物化石组合带：１．早二叠世中期山西组Ｅｍｐｌｅｃｔｏｐｔｅｒｉｓｔｒｉａｎｇｕｌａｒｉｓ－Ｔａｅｎｉｏｐｔｅｒｉｓｍｕｌｔｉｎｅｒｖｉｓａｓ－ｓｅｍｂｌａｇｅｚｏｎｅ；２．早二叠世晚期下石盒子组Ｇｉｇａｎｔｏｐｔｅｒｉｓｎｉｃｏｔｉａｎａｅｆｏｌｉａ－Ｃｈｉｒｏｐｔｅｒｉｓｒｅｎｉｆｏｒｍｉｓａｓｓｅｍｂｌａｇｅｚｏｎｅ；３．晚二叠世早期上石盒子组Ｌｏｂａｔａｎｎｕｌａｒｉａｈｅｉａｎｅｎｓｉｓ－Ｐｔｅｒｏｐｈｙｌｌｕｍｅｒａｔｕｍａｓ－ｓｅｍｂｌａｇｅｚｏｎｅ。另外，文中还讨论了这些植物组合的主要特点 相似文献
19.
Based on the pollen data obtained from thirty-five surface soil samples and investigated vegetation data from seven plant
quadrats, the quantitative relationship between surface soil pollen and modern vegetation are studied in the longitudinal
range-gorge region (LRGR) in Southwestern China. R-values (referring to pollen assemblages) are calculated with pollen percentage and plant abundance. The coefficients of similarity
between pollen and vegetation are analyzed. The results show that the pollen assemblages on surface soil of all vegetation
zones can basically represent the native vegetation, but the pollen assemblages are not fully according with the vegetation.
This is due to the influencing factors including pollen preservation ability, pollen production, amount of exotic pollen and
pollen identification. The pollen representation in surface soil is different in families and genera. The pollen of woody
plants such as Pinus, Tsuga, Alnus, Fagus and Castanopsis are over-representative, but those of Quercus, Carpinus Myrica, Elaeocarpaceae, Ericaceae, Theaceae and Llex are underrepresentative; the pollen of herbaceous plants such as Artemisia and Rubiaceae are over-representative, while those of others including Gramineae and Araliaceae are under-representative.
The R-values of the same taxon pollen in different vegetation zones are different, depending on their distances from the pollen sources.
The coefficients of the similarity between plant communities and pollen assemblages are mostly over 70%, which indicate again
that the surface soil pollen and spores assemblages can represent the vegetation. It is concluded that there is a good corresponding
relationship between surface pollen assemblages and native vegetation in LRGR, and it is of great significance for reconstructing
the past vegetation and paleoclimate using quantitative fossil pollen data in this region. 相似文献
20.
《山地科学学报》2020,17(1):83-94
Environmental variations and ontogeny may affect plant morphological traits and biomass allocation patterns that are related to the adjustments of plant ecological strategies. We selected 2-, 3-and 4-year-old Fritillaria unibracteata plants to explore the ontogenetic and altitudinal changes that impact their morphological traits(i.e., plant height, single leaf area,and specific leaf area) and biomass allocations [i.e.,biomass allocations of roots, bulbs, leaves, stems, and flowers] at relatively low altitudinal ranges(3400 m to 3600 m asl) and high altitudinal ranges(3600 m to4000 m asl). Our results indicated that plant height,root biomass allocation, and stem biomass allocation significantly increased during the process of individual growth and development, but single leaf area, specific leaf area, bulb biomass allocation, and leaf biomass allocation showed opposite trends.Furthermore, the impacts of altitudinal changes on morphological traits and biomass allocations had no significant differences at low altitude, except for single leaf area of 2-year-old plants. At high altitude,significantly reduced plant height, single leaf area and leaf biomass allocation for the 2-year-old plants,specific leaf area for the 2-and 4-year-old plants, and stem biomass allocation were found along altitudinal gradients. Significantly increased sexual reproductive allocation and relatively stable single leaf area and leaf biomass allocation were also observed for the 3-and 4-year-old plants. In addition, stable specific leaf area for the 3-year-old plants and root biomass allocation were recorded. These results suggested that the adaptive adjustments of alpine plants, in particular F. unibracteata were simultaneously influenced by altitudinal gradients and ontogeny. 相似文献