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101.
A new ascomycete species, Jahnula apiospora (Jahnulales, Dothideomycetes), collected from submerged wood in a freshwater creek on Prince Edward Island, Canada, is described
and illustrated. The characteristic features of the new species are globose to subglobose, black, ostiolate, membranous ascomata
with broad, brown, subtending hyphae; a peridial wall composed of an outer layer of thick-walled cells occluded by black,
amorphous material along the upper two-thirds of the ascoma; trabeculate pseudoparaphyses; cylindrical to narrowly fusoid,
fissitunicate asci; and brown, one-septate, apiosporous ascospores without a gelatinous sheath or appendages. 相似文献
102.
Abstract: We re-examine the type series of ' Sinemys ' wuerhoensis Yeh (at least 20 specimens, including several shells and skulls on three slabs of matrix and one isolated skull) from the Early Cretaceous Tugulu Group of China. Our study shows that the type series of ' S. ' wuerhoensis is actually a chimera made up of at least three distinct taxa. The holotype of this taxon should be assigned to the basal eucryptodire genus Xinjiangchelys Yeh. As there are no characters that distinguish ' S. ' wuerhoensis from Xinjiangchelys species, we consider it to be a nomen dubium . This new assignment of ' S. ' wuerhoensis expands the temporal range of Xinjiangchelys from the Late Jurassic into the Early Cretaceous in Asia. The majority of the paratypes of ' S. ' wuerhoensis (several shells in dorsal and ventral aspect and skulls) are referred to the basal eucryptodire genus Ordosemys Brinkman and Peng. We establish a new name for these specimens, Ordosemys brinkmania sp. nov. One additional specimen in the type series of ' S. ' wuerhoensis , a skull, is referred to cf. Pantrionychia Joyce, Parham and Gauthier indet. 相似文献
103.
104.
The early Eocene birds of the Messel fossil site: a 48 million‐year‐old bird community adds a temporal perspective to the evolution of tropical avifaunas 下载免费PDF全文
Gerald Mayr 《Biological reviews of the Cambridge Philosophical Society》2017,92(2):1174-1188
Birds play an important role in studies addressing the diversity and species richness of tropical ecosystems, but because of the poor avian fossil record in all extant tropical regions, a temporal perspective is mainly provided by divergence dates derived from calibrated molecular analyses. Tropical ecosystems were, however, widespread in the Northern Hemisphere during the early Cenozoic, and the early Eocene German fossil site Messel in particular has yielded a rich avian fossil record. The Messel avifauna is characterized by a considerable number of flightless birds, as well as a high diversity of aerial insectivores and the absence of large arboreal birds. With about 70 currently known species in 42 named genus‐level and at least 39 family‐level taxa, it approaches extant tropical biotas in terms of species richness and taxonomic diversity. With regard to its taxonomic composition and presumed ecological characteristics, the Messel avifauna is more similar to the Neotropics, Madagascar, and New Guinea than to tropical forests in continental Africa and Asia. Because the former regions were geographically isolated during most of the Cenozoic, their characteristics may be due to the absence of biotic factors, especially those related to the diversification of placental mammals, which impacted tropical avifaunas in Africa and Asia. The crown groups of most avian taxa that already existed in early Eocene forests are species‐poor. This does not support the hypothesis that the antiquity of tropical ecosystems is key to the diversity of tropical avifaunas, and suggests that high diversification rates may be of greater significance. 相似文献
105.
Hasan Rüstü Kutlu Ilknur Ünsal Murat Grgülü 《Animal Feed Science and Technology》2001,90(3-4):213-226
Three experiments were carried out to determine whether dietary wood (oak) charcoal applied during entire or phase feeding period would affect growth performance, abdominal fat weight, carcass weight, carcass yield, carcass composition and nutrient excretion of broilers and to determine whether dietary wood charcoal supplementation would affect laying performance and egg quality of laying hens. In the first experiment, different inclusion levels (0, 25, 50 and 100 g/kg feed) of wood charcoal in the diet were examined for a 6-week-period using broiler chicks of initial age 1 week. Dietary wood charcoal significantly increased feed intake (P<0.001), body weight gain (P<0.001) and improved feed conversion ratio (P<0.05) up to 28 days of age. However, at 49 days of age, charcoal inclusion did not significantly (P>0.05) affect body weight gain, feed intake, carcass weight and carcass yield, but increased (P<0.05) feed conversion ratio, carcass ash content, fat excretion, while reducing (P<0.05) mineral excretion in a dose dependent manner. In the second experiment, a phase application of dietary wood charcoal for a 6-week-period broiler chicks of initial age 1 week was assessed. During the first 28 days of age wood charcoal improved feed conversion ratio significantly (P<0.05). At 49 days of age, the groups receiving charcoal in the starter and/or finisher diets showed significantly (P<0.05) higher body weight gain and carcass weight than the control group receiving no charcoal. In the third experiment, different levels (0, 10, 20 and 40 g/kg feed) of wood charcoal supplementation to a layer diet were examined for a 7-week-period using laying hens of initial age 34 weeks. Dietary charcoal supplementation did not have a significant effect on any parameters related to performance and egg quality, but significantly reduced number of cracked eggs and the reduction was dose dependent (P<0.01). These data demonstrate that wood charcoal inclusion to the diet could be of value in improving broiler performance during the first 28 days of fattening period. In later ages, the positive effects of wood charcoal are limited. However, in laying hens dietary supplementation of wood charcoal reduces number of cracked eggs. 相似文献
106.
Fine root growth and element concentrations of Norway spruce as affected by wood ash and liquid fertilisation 总被引:2,自引:1,他引:2
M. Genenger S. Zimmermann D. Hallenbarter W. Landolt E. Frossard I. Brunner 《Plant and Soil》2003,255(1):253-264
A field experiment to test various management practices of sustainable forestry was conducted in a Swiss spruce forest for two growing seasons. Treatments were a control (C), yearly application of 4000 kg ha–1 wood ash (A), daily irrigation with a steady state fertilisation as `optimal nutrition` (F) and irrigation with a water control (W). Samples were taken on a 5 × 5 m grid once a year with a soil corer to determine fine root biomass ( 2 mm) and soil pH of the topsoil. A subset of the fine root samples was further analysed for its nutrient composition by CN and ICP-AES analyses. The dynamics of root growth were observed with the aid of ingrowth-cores after 1, 1.5, and 2 years of treatment and the growth pattern was analysed in terms of biomass, tips, forks, length and root diameter of the samples. The A, F and also the W treatment resulted in a significant increase of soil pH in the topsoil. The fine root density increased over the two growing seasons, irrespective of the treatment. The root growth was only slightly different between the treatments with a initially faster growth under the A treatment. The W treatment reduced the number of root tips and forks, and the root length, while the A treatment increased the number of root tips, forks and the root length, but reduced the diameter. The differences between the three harvesting times (March 1999, October 1999, March 2000) of the ingrowth-cores stressed seasonal differences in root growth and the development of quasi `steady state' root dynamics. The root turnover was not changed by the treatments. The elements in the fine roots were strongly affected by the treatments A and F and sometimes by W. Fine root N increased with the F treatment, while C concentrations decreased under the A, F and W treatments. The Ca and Mg concentrations were strongly enhanced by A but also by the F treatment. The K and P concentrations in the fine roots were improved by all three applications. Due to the pH increase Al, Fe and Mn concentrations in the fine roots were decreased by the A and F treatments. S and Zn concentrations showed inconsistent changes over the growing seasons. The results of this study were comparable with those of other studies in Europe and confirm the abilities of the fine roots as indicators of forest nutrition, to some extent more sensitive than the commonly used foliar analysis. 相似文献
107.
Lech Michalczuk 《Acta Physiologiae Plantarum》2002,24(2):131-136
Free and conjugated IAA levels were determined in wood, bark and cambial sap of M.9, M.26 and MM.106 apple rootstock genotypes
differing in growth vigour. The measurements were done on May 15th, June 15th and July 15th. The level of free IAA in bark and wood of the tested trees varied from 27.0 to 52.7 ng·g−1 f.w. while the conjugated hormone content averaged 3–5 times higher. In the bark and wood samples, the differences in auxin
content between rootstock genotypes and the time of stem harvesting were insignificant. The level of free IAA in cambial sap
was on average 10 to 20 times higher than in both bark and wood tissues, while the conjugated hormone level varied from none
(below detection limit) to 37 ng·g−1 f.w. Content of free IAA level in cambial sap from dwarf M.9 rootstock was significantly lower than that in either of the
more vigorous genotypes. In both vigorous rootstocks IAA level in cambial sap remained at a similar level at all sampling
dates but M.9 cambial sap showed a trend towards decreasing auxin content later in the growing season. 相似文献
108.
Hierarchically Porous,Ultrathick, “Breathable” Wood‐Derived Cathode for Lithium‐Oxygen Batteries 下载免费PDF全文
Huiyu Song Shaomao Xu Yiju Li Jiaqi Dai Amy Gong Mingwei Zhu Chunliang Zhu Chaoji Chen Yanan Chen Yonggang Yao Boyang Liu Jianwei Song Glenn Pastel Liangbing Hu 《Liver Transplantation》2018,8(4)
In this work, a hierarchically porous and ultrathick “breathable” wood‐based cathode for high‐performance Li‐O2 batteries is developed. The 3D carbon matrix obtained from the carbonized and activated wood (denoted as CA‐wood) serves as a superconductive current collector and an ideal porous host for accommodating catalysts. The ruthenium (Ru) nanoparticles are uniformly anchored on the porous wall of the aligned microchannels (denoted as CA‐wood/Ru). The aligned open microchannels inside the carbon matrix contribute to unimpeded oxygen gas diffusion. Moreover, the hierarchical pores on the microchannel walls can be facilely impregnated by electrolyte, forming a continuous supply of electrolyte. As a result, numerous ideal triphase active sites are formed where electrolyte, oxygen, and catalyst accumulate on the porous walls of microchannels. Benefiting from the numerous well‐balanced triple‐phase active sites, the assembled Li‐O2 battery with the CA‐wood/Ru cathode (thickness: ≈700 µm) shows a high specific area capacity of 8.58 mA h cm?2 at 0.1 mA cm?2. Moreover, the areal capacity can be further increased to 56.0 mA h cm?2 by using an ultrathick CA‐wood/Ru cathode with a thickness of ≈3.4 mm. The facile ultrathick wood‐based cathodes can be applied to other cathodes to achieve a super high areal capacity without sacrificing the electrochemical performance. 相似文献
109.
KATRI KOSTIAINEN PEKKA SARANPÄÄ SVEN‐OLOF LUNDQVIST MARK E. KUBISKE ELINA VAPAAVUORI 《Plant, cell & environment》2014,37(6):1452-1463
We studied the interactive effects of elevated concentrations of CO2 and O3 on radial growth and wood properties of four trembling aspen (Populus tremuloides Michx.) clones and paper birch (Betula papyrifera Marsh.) saplings. The material for the study was collected from the Aspen FACE (free‐air CO2 enrichment) experiment in Rhinelander (WI, USA). Trees had been exposed to four treatments [control, elevated CO2 (560 ppm), elevated O3 (1.5 times ambient) and combined CO2 + O3] during growing seasons 1998–2008. Most treatment responses were observed in the early phase of experiment. Our results show that the CO2‐ and O3‐exposed aspen trees displayed a differential balance between efficiency and safety of water transport. Under elevated CO2, radial growth was enhanced and the trees had fewer but hydraulically more efficient larger diameter vessels. In contrast, elevated O3 decreased radial growth and the diameters of vessels and fibres. Clone‐specific decrease in wood density and cell wall thickness was observed under elevated CO2. In birch, the treatments had no major impacts on wood anatomy or wood density. Our study indicates that short‐term impact studies conducted with young seedlings may not give a realistic view of long‐term ecosystem responses. 相似文献
110.
Perforation plates and other vessel details as studied with scanning electron microscopy (SEM) have been reported for four
species of Cornaceae (s.l.): similar features are shown by the four, suggesting that a more extensive sampling of the family
might reveal similar phenomena. Perforation plates contain pit membrane remnants in the form of threads or, less commonly,
laminar portions perforated by pores. When least well-represented, the pit membrane remnants are restricted to lateral ends
of perforations and to the perforations transitional to lateral wall pitting. Perforations are all clearly bordered. Helical
thickenings that do not form a continuous gyre are reported for the vessel walls ofAucuba. The presence of pit membrane remnants in vessel elements of Cornaceae correlates with the mesic habitats occupied by species
in this family. The presence and type of pit membrane remnants reported by us in the three genera is very similar, although
pit membrane remnants are doubtless a symplesiomorphy and thus not an indicator of relationships. The presence of pit membrane
remnants in the three genera, however, does attest to the primitiveness of wood and other features of Cornaceae s.l. 相似文献