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International Journal of Biometeorology - 相似文献
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Sophie-Marie Aicher Felix Streicher Maxime Chazal Delphine Planas Dongsheng Luo Julian Buchrieser Monika Nemcova Veronika Seidlova Jan Zukal Jordi Serra-Cobo Dominique Pontier Bertrand Pain Gert Zimmer Olivier Schwartz Philippe Roingeard Jiri Pikula Laurent Dacheux Nolwenn Jouvenet 《Journal of virology》2022,96(14)
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Anthony I. Cognato Jiri Hulcr Stephanie A. Dole Bjarte H. Jordal 《Zoologica scripta》2011,40(2):174-186
Cognato, A. I., Hulcr, J., Dole, S. A. & Jordal, B. H. (2010). Phylogeny of haplo‐diploid, fungus‐growing ambrosia beetles (Curculionidae: Scolytinae: Xyleborini) inferred from molecular and morphological data. —Zoologica Scripta, 40, 174–186. The ambrosia beetle tribe Xyleborini currently contains 30 genera and approximately 1200 species which are distributed throughout worldwide forests with most diversity located in the tropics. They also represent the most invasive scolytines in North America. Despite economic concerns and biological curiosity with this group, a comprehensive understanding of generic boundaries and the evolutionary relationship among species is lacking. In this study, we include 155 xyleborine species representing 23 genera in parsimony and Bayesian analyses using 3925 nucleotides from mitochondrial (COI) and nuclear genomes (28S, ArgK, CAD, EF‐1α) and 39 morphological characters. The phylogenies resulting from the parsimony analyses, which treated gap positions either as missing or fifth character states, and the Bayesian analysis were generally similar. Clades with high support or posterior probabilities were found in all trees, while those with low support were not recovered by all analyses. Fourteen of the 23 genera were monophyletic although not all relationships among the genera were resolved. We show monophyly of several species groups associated with particular morphological and biological characters and suggest recognition of these groups as genera. Most interesting was the monophyly of South and Central American species representing several genera. This finding suggests recent and fast radiation of xyleborines in the New World accompanied by morphological and biological diversification. 相似文献
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Rapid degradation of pyrogenic carbon 总被引:6,自引:0,他引:6
Michael Zimmermann Michael I. Bird Christopher Wurster Gustavo Saiz Iain Goodrick Jiri Barta Petr Capek Hana Santruckova Ronald Smernik 《Global Change Biology》2012,18(11):3306-3316
Pyrogenic carbon (PC‐ charcoal, biochar or black carbon) represents a poorly understood component of the global carbon (C) cycle, but one that has considerable potential to mitigate climate change through provision of long‐term soil C sequestration. Mass balance calculations suggest global PC production and stocks are not in balance, indicating a major gap in our understanding of the processes by which PC is re‐mineralized. We collected PC samples derived from the same wood material and exposed to natural environmental conditions for 1 and 11 years. We subjected these materials to repeated laboratory incubation studies at temperatures of up to 60 °C, as ground surface temperatures above 30 °C and up to 60 °C occur regularly over a significant area of the tropics and sub‐tropics. Mineralization rates were not different for the two samples and followed an exponential Arrhenius function that suggest an average turnover time of 67 years for conditions typical of a tropical savannah environment. Microbial biomass as measured by chloroform fumigation and DNA extractions was the same for the two samples, but abiotic CO2 production was lower for the fresh PC sample than that for the aged sample. Nuclear magnetic resonance spectroscopy, hydrogen pyrolysis and scanning electron microscopy demonstrate that the measured CO2 production originates dominantly from polycyclic aromatic compounds rather than any minor labile components. Therefore, rapid, sub‐centennial rates of re‐mineralization of PC on the soil surface in tropical and sub‐tropical environments may represent a major and hitherto unidentified mechanism for balancing the PC production at the global scale. 相似文献
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Inada NM da Silva AR Jorge RA Borecký J Vercesi AE 《Archives of biochemistry and biophysics》2007,457(2):217-224
The action of irradiated cationic Fe(III)TMPyP and anionic Fe(III)TPPS4 forms of mesoporphyrins on mitochondrial functions was investigated using experimental conditions that caused minimal effects on mitochondria in the dark. Treatment of mitochondria with 1 microM Fe(III)TMPyP for 2 min decreased the respiratory control by 3% in the dark and 28% after irradiation. Fe(III)TPPS4 (1 microM) had no significant effect on respiratory control under any of the above conditions. Both porphyrins increased the mitochondrial production of reactive oxygen species in the presence of Ca2+; however, the effect of Fe(III)TMPyP was significantly stronger. In both cases, this overproduction was associated with membrane lipid peroxidation. It was also observed that the association constant of Fe(III)TMPyP with mitochondria was 11 times higher than that of Fe(III)TPPS4. In conclusion, the damage to isolated mitochondria induced by Fe(III)TMPyP under illumination was larger than by Fe(III)TPPS4, probably because its cationic charge favors association with the mitochondrial membrane. This is supported by the decrease in the association constant of Fe(III)TMPyP with mitochondria in higher salt medium. 相似文献
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<Emphasis Type="Italic">Daphnia galeata</Emphasis> in the deep hypolimnion: spatial differentiation of a “typical epilimnetic” species 总被引:1,自引:1,他引:1
One of the most serious threats to tropical mangrove ecosystems caused by shrimp farming activities is the poor management
of pond waste materials. We hypothesise that mangroves can tolerate chemical residues discharged from shrimp farms and can
be used as biofilters, but the capability of mangroves to cope with solid sediments dredged from shrimp ponds is limited.
Our study in Pak Phanang, Thailand, confirmed that the excess sediments discharged from nearby shrimp ponds reduced mangrove
growth rates and increased mortality rates. A series of transformed multi-temporal satellite images was used in combination
with the field data to support this claim. In addition, a comparison between four dominant mangrove species revealed that
Avicennia marina could tolerate sedimentation rates of >6 cm year−1, while Bruguiera cylindrica tolerated sedimentation rates of 5 cm year−1 (total sediment depth = 25 cm) before dying, while Excoecaria agallocha and Lumnitzera racemosa performed intermediate. This outcome implied that in our situation A. marina and to lesser extent E. agallocha and L. racemosa could be more effective as biofilters than B. cylindrica, as they may survive the sedimentation longer in the disposal areas. Further studies on the impact of sedimentation and chemical
pollution of shrimp farm wastes on mangrove mortality and growth are required. 相似文献