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221.
Amezaga I. Gonzalez Arias A. Domingo M. Echeandia A. Onaindia M. 《Water, air, and soil pollution》1997,97(3-4):303-313
The effect of forest canopy on the chemical composition of Throughfall was studied in four forests, two coniferous plantations of Pinus radiata and two deciduous forests (Quercus robur and Q.rubra, respectively) near bilbao (Bizkaia), Basque Country (Northern Spain) during one year. The study areas are assumed to have different levels of pollution: Manzanal suffers industrial pollution mainly of SO4 2‐ and N.NO3 ‐, while Durango has industrial and agricultural pollution mainly of N.NH4 + and SO4 2‐ 相似文献
222.
Role of Gene Interactions in Hybrid Speciation: Evidence from Ancient and Experimental Hybrids 总被引:6,自引:0,他引:6
LH Rieseberg B Sinervo CR Linder MC Ungerer DM Arias 《Science (New York, N.Y.)》1996,272(5262):741-745
The origin of a new diploid species by means of hybridization requires the successful merger of differentiated parental species' genomes. To study this process, the genomic composition of three experimentally synthesized hybrid lineages was compared with that of an ancient hybrid species. The genomic composition of the synthesized and ancient hybrids was concordant (rs = 0.68, P < 0.0001), indicating that selection to a large extent governs hybrid species formation. Further, nonrandom rates of introgression and significant associations among unlinked markers in each of the three synthesized hybrid lineages imply that interactions between coadapted parental species' genes constrain the genomic composition of hybrid species. 相似文献
223.
Otaiza-González Santiago N. Mary Verónica S. Arias Silvina L. Bertrand Lidwina Velez Pilar A. Rodriguez María G. Rubinstein Héctor R. Theumer Martín G. 《European journal of plant pathology / European Foundation for Plant Pathology》2022,162(1):203-219
European Journal of Plant Pathology - Fusarium graminearum and Zymoseptoria tritici cause economically important diseases of wheat. F. graminearum is one of the primary causal agents of Fusarium... 相似文献
224.
D. Fernndez‐Calvio J. C. Nvoa‐Muoz E. Lpez‐Periago M. Arias‐Estvez 《Land Degradation \u0026amp; Development》2008,19(2):165-177
We studied total Cu content and its distribution in 33 surface soil samples cultivated with vines for variable lengths of time in the Monterrei designation of origin (DO), located in Galicia (NW Spain). The study was focused on the influence of land use changes on soil degradation by effect of Cu accumulation and availability. Total copper concentration in soils ranged from 25 to 272 mg kg−1. The time during which each soil was cultivated with vines was found to affect both the total concentration of copper and its distribution. The average concentration of copper in young vineyards was 64 mg kg−1, whereas those in old and abandoned vineyards were 100 and 132 mg kg−1, respectively. Copper bound to organic matter and to amorphous inorganic colloids were greater in old and abandoned vineyards, where they accounted for 51 and 52 per cent, respectively, of total copper, than in young vineyards (39 per cent). Copper bound to crystalline Al and Fe colloids accounted for 21, 22 and 12 per cent of total Cu in old, abandoned and young vineyards respectively. The prevalence of Cu bound to the organic fraction reduces the adverse environmental effects of this metal on soil organisms and plants. However, some management practices such as organic matter addition or liming should be implemented in order to delay or avoid soil degradation in young vineyards. For abandoned vineyards, the influence of new land uses on potential Cu mobilisation necessitates careful examination. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
225.
226.
Lipopolysaccharide (LPS) and total protein profiles from four Flavobacterium columnare isolates were compar. These strains belonged to genetically different groups and/or presented distinct virulence properties. Flavobacterium columnare isolates ALG-00-530 and ARS-1 are highly virulent strains that belong to different genomovars while F. columnare FC-RR is an attenuated mutant used as a live vaccine against F. columnare. Strain ALG-03-063 is included in the same genomovar group as FC-RR and presents a similar genomic fingerprint. Electrophoresis of LPS showed qualitative differences among the four strains. Further analysis of LPS by immunoblotting revealed that the avirulent mutant lacks the higher molecular bands in the LPS. Total protein analysis displayed by immunoblotting showed differences between the strains analysed although common bands were present in all the isolates. FC-RR lacked two distinct common bands (34 and 33 kDa) shared by the other three isolates. Based on the difference of LPS and total protein profiles, it is possible to discriminate the attenuated mutant FC-RR from other F. columnare strains. 相似文献
227.
I. Pinaya B. Soto M. Arias F. Díaz‐Fierros 《Land Degradation \u0026amp; Development》2000,11(1):93-98
The efficiency of revegetation of burnt areas was put to the test with two different mixes of grasses, one comprising native species and the other, including Lolium multiflorum, sown by hand. Runoff generation and soil loss were studied over the first 20 months after the fire in seeded plots (two plots for each seed mix) and in an unseeded plot (considered as the control). The seeded plots showed a marked increase in vegetation, and 6 months after the fire ground cover was about 60 per cent in the plots seeded with native species. This ground cover value (considered to be the cover necessary for good protection against soil erosion) was reached in plots seeded with the commercial mix after 8 months and in the control plot after 14 months. Runoff volume was similar in all plots, but the soil erosion was reduced in both seeded plots by a factor of 6·5. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献