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21.
E. Blaser 《Journal of pest science》1960,33(2):28-30
Ohne Zusammenfassung 相似文献
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Zeeh F Zimmermann W Eichhorn L Welle M Blaser P Albini S 《Schweizer Archiv für Tierheilkunde》2010,152(11):523-527
A fattening pig with enlarged head and abdominal lymph nodes was examined. An aspirate of the abscesses did not produce a conclusive diagnosis. Only an excision with subsequent histological and bacteriological examination showed the mould Mycocladus corymbiferus (syn. Absidia corymbifera) to be present. Similar abscesses should be examined as actinomycosis and leucosis are the main differential diagnoses. 相似文献
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In the context of pollution‐control strategies to minimize the detrimental effects of soil acidification, there is a need to know how and to what extent soils respond to acidifying substances. The purposes of this study were to assess the sensitivity of soil to acidification, in particular to a decrease in pH and in base saturation (BS), and the risk of Al toxicity for vulnerable plants using chemical indicators. These indicators were derived from soil data (pH, exchangeable cations, amount of fine earth) measured in the mineral horizons of 257 soil profiles throughout Switzerland. Based on the analysis of the distribution of pH and BS values in the soil collective, we assessed the sensitivity of soils to a decrease in pH and in BS. Soils that were considered sensitive to a decrease in pH had pH values between 4.8 and 7.0. The degree of sensitivity was estimated with the proportion of fine earth in the critical pH range to a depth of 100 cm. Soils that were considered sensitive to a decrease in BS had pH values between 3.6 and 5.5 and a BS between 10% and 95%. Since the effective cation‐exchange capacity (CECeff) of the fine earth might dampen the decrease in BS when acidity is added, the disposition for a decrease in BS was related to the relative amount of fine earth in the sensitive BS and to the mean CECeff of this fine‐earth fraction. The risk of Al toxicity for vulnerable plants was estimated using the ratio of base cations to Al at the cation‐exchange sites (BC : Alexc). A BC : Alexc of 0.2 was taken as a threshold value below which the risk for sensitive plants increases. The degree of risk was based on the proportion of fine earth in the critical BC : Al range (≤0.2) in the soil profile. These indicators taking into account the various aspects of soil acidification are derived from usually available data and represent therefore a cost‐effective tool to assess the sensitivity of soils to an input of acidity. 相似文献
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Haeler Elena Bergamini Ariel Blaser Stefan Ginzler Christian Hindenlang Karin Keller Christine Kiebacher Thomas Kormann Urs G. Scheidegger Christoph Schmidt Ronald Stillhard Jonas Szallies Alexander Pellissier Loïc Lachat Thibault 《Landscape Ecology》2021,36(1):89-104
Context
Dead wood is a key habitat for saproxylic species, which are often used as indicators of habitat quality in forests. Understanding how the amount and spatial distribution of dead wood in the landscape affects saproxylic communities is therefore important for maintaining high forest biodiversity.
ObjectivesWe investigated effects of the amount and isolation of dead wood on the alpha and beta diversity of four saproxylic species groups, with a focus on how the spatial scale influences results.
MethodsWe inventoried saproxylic beetles, wood-inhabiting fungi, and epixylic bryophytes and lichens on 62 plots in the Sihlwald forest reserve in Switzerland. We used GLMs to relate plot-level species richness to dead wood amount and isolation on spatial scales of 20–200 m radius. Further, we used GDMs to determine how dead wood amount and isolation affected beta diversity.
ResultsA larger amount of dead wood increased beetle richness on all spatial scales, while isolation had no effect. For fungi, bryophytes and lichens this was only true on small spatial scales. On larger scales of our study, dead wood amount had no effect, while greater isolation decreased species richness. Further, we found no strong consistent patterns explaining beta diversity.
ConclusionsOur multi-taxon study shows that habitat amount and isolation can strongly differ in the spatial scale on which they influence local species richness. To generally support the species richness of different saproxylic groups, dead wood must primarily be available in large amounts but should also be evenly distributed because negative effects of isolation already showed at scales under 100 m.
相似文献26.
Goldman CG Matteo MJ Loureiro JD Almuzara M Barberis C Vay C Catalano M Heredia SR Mantero P Boccio JR Zubillaga MB Cremaschi GA Solnick JV Perez-Perez GI Blaser MJ 《Veterinary microbiology》2011,152(1-2):138-145
The mammalian gastric and oral mucosa may be colonized by mixed Helicobacter and Campylobacter species, respectively, in individual animals. To better characterize the presence and distribution of Helicobacter and Campylobacter among marine mammals, we used PCR and 16S rDNA sequence analysis to examine gastric and oral samples from ten dolphins (Tursiops gephyreus), one killer whale (Orcinus orca), one false killer whale (Pseudorca crassidens), and three wild La Plata river dolphins (Pontoporia blainvillei). Helicobacter spp. DNA was widely distributed in gastric and oral samples from both captive and wild cetaceans. Phylogenetic analysis demonstrated two Helicobacter sequence clusters, one closely related to H. cetorum, a species isolated from dolphins and whales in North America. The second related cluster was to sequences obtained from dolphins in Australia and to gastric non-H. pylori helicobacters, and may represent a novel taxonomic group. Dental plaque sequences from four dolphins formed a third cluster within the Campylobacter genus that likely represents a novel species isolated from marine mammals. Identification of identical Helicobacter spp. DNA sequences from dental plaque, saliva and gastric fluids from the same hosts, suggests that the oral cavity may be involved in transmission. These results demonstrate that Helicobacter and Campylobacter species are commonly distributed in marine mammals, and identify taxonomic clusters that may represent novel species. 相似文献
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A field study was conducted at the Research Farm of NWFP, Agricultural University, Pakistan. Chickpea (Cicer aeritinum L.) cultivar, ‘Hassan-2000’, was sown as a winter crop under conventional tillage (CT) or no-tillage (NT) dryland systems in a randomized complete block design with split plot arrangement using four replications. Three levels of phosphorus (P; 0, 80 and 120 kg P2O5 ha?1) were broadcast applied at the time of last plowing and were thoroughly mixed in subplot size of 1.8 × 5 m. About 20% less weed biomass and 2% higher grain yield was recorded under CT than in NT. Plots supplied with P2O5 had higher value of the all the parameters under study except number of plant m?2 when compared with control (no P applied). However, the grain yield response to P beyond 80 kg ha?1 was not positive. CT + 80 kg P2O5 ha?1 was identified as the optimum level for maximum chickpea production under the existing dryland condition where application of herbicides in NT is not possible. Further experiments to study the optimization of P in chickpea production under dryland conditions are required. 相似文献
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Blaser M Bertagnoli A Räber M Nuss K Rasekh M Steiner A 《Veterinary journal (London, England : 1997)》2012,193(3):701-706
The objective of the present study was to describe the arthroscopic anatomy of the bovine fetlock joint using one palmar/plantar and three dorsal joint approaches. A comparative anatomic, ultrasonographic and arthroscopic study using 20 cadaveric feet from 13 non-lame adult dairy cows was performed. Arthroscopy was accomplished using a rigid arthroscope to view the synovial cavities with their synovial villi and parts of the following structures: the distal ends of the metacarpal/metatarsal III/IV bones with their trochleae and sagittal ridges, synovial grooves, the articular surfaces of the proximal sesamoid bones, the proximal aspects of the first phalanges, the lateral and medial collateral ligaments, the suspensory ligament and the interdigital ligaments as parts of the interosseus muscle, the cruciate sesamoidean ligaments, the communication site between the lateral and medial pouch in the palmar/plantar area, and dorsally the septum between the lateral and the medial pouch. The technique allowed a good overall view of most relevant structures in the sound cadaver joint. Further investigations are warranted to evaluate the diagnostic, therapeutic and prognostic applications of these techniques in the treatment of septic arthritis. 相似文献
29.
Sorption and transport of metals in preferential flow paths and soil matrix after the addition of wood ash 总被引：1，自引：0，他引：1
As a consequence of heterogeneous transport in soils, only a small part of the soil might be responsible for sorbing incoming elements. After staining preferential flow paths in forested Dystric Cambisol with a colour dye, we sampled soil material from the flow paths and from the soil matrix. We measured chemical properties and sorption isotherms of these two flow regions and estimated the significance of preferential flow paths for the transport of solutes leached from wood ash applied at the surface. In the A horizon (0–9 cm depth), the cation exchange capacity of the flow paths was 83.8 mmolc kg?1, while that of the soil matrix was only 74.6 mmolc kg?1. The base saturation was 42% and soil organic matter content was 41% larger in flow paths than in the soil matrix. The sorption capacity for Cu was also larger than in the matrix, whereas the sorption capacity for Sr was similar in both flow regions. The impact of the addition of 8 t wood ash ha?1 on soil chemical properties was restricted mainly to the flow paths in the uppermost 20 cm of the soil; it was negligible in the matrix and at greater depths. Concentrations of exchangeable Ca in the flow paths increased nearly 10‐fold during the 6 months following the addition of the wood ash, and those of organically bound Pb by 50%. The opposite effect was found for exchangeable Al. Our results show that only part of the whole soil volume, approximately 50% of 0–20 cm in our study, is involved in transporting and sorbing the elements applied with the wood ash or as tracers. Such differences must be considered when calculating the maximal impact of any addition of fertilizer, wood ash, or liming agent. 相似文献
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Mineralization of soil organic matter and of added 14C labelled substrates were studied on samples from two acidic forest soils, “Cademario”-sample from the Bh-horizon of a cryptopodzolic soil rich in humus and nonexchangeable Al and “Sagno”-sample from the A-horizon of a Haplumbrept with moderate humus- and Al-content. The respiration rates for the two soils were not different when related to the content of organic matter. When treated with Na2CO3, the CO2 production rate in the Sagno soil increased about three fold whereas no significant difference was observed for Cademario samples. This is attributed to the more pronounced dissolution of organic matter due to the pH increase in the Sagno soil. N-mineralization was different in the two soils. During a 28 day incubation period, 0.11% and 0.34% of the total organic N was released in the Cademario and Sagno samples, respectively. Na2CO3 treatment stimulated N-mineralization in both soils but the mineral N-form was primarily nitrate in the Sagno sample and ammonium in the aluminum-rich sample from Cademario. Glucose, succinate and salicylate added to the soils were mineralized in this order. However, CO2 evolution was much slower in the case of salicylate, especially in the untreated soils, a fact which is attributed to the Al-complexing power of this substrate. 相似文献