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1.
R. Michael Erwin 《Biological conservation》1980,18(1):39-51
More than 80% of the beach-nesting seabirds (common tern, least tern, black skimmer, and herring gull) in coastal Virginia nest on natural barrier island beaches, while in New Jersey the vast majority nest on dredge deposition material or natural marsh islands. This contrast probably results from the differences in human disturbance in the two regions. Although 75% of all oceanfront in New Jersey allows unrestricted recreation, about 85% of the Virginia beaches are ‘protected’ under the ownership of several conservation agencies. Attendant with changes in habitat utilisation in New Jersey, competitive interactions have apparently intensified with herring gulls usurping tern and laughing gull nest sites. Other implications are discussed. 相似文献
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Erwin Otten 《Journal of pest science》1948,21(4):59-60
Ohne Zusammenfassung 相似文献
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Erwin Aichinger und Rudolf Siegrist 《Forstwissenschaftliches Centralblatt》1930,52(20):793-809
Ohne Zusammenfassung 相似文献
4.
Dwarf shrub litter is thought to be of poor quality and palatability for macro-decomposers. In laboratory feeding experiments, however, it was found that this litter type represents a potential food source for earthworms and millipedes. Here we tested whether this is true under natural conditions by conducting a 1 year field experiment on an abandoned alpine pasture in Tyrol (Austria). As the natural isotopic signatures of plant litter do not allow discriminating between different plant species, dwarf shrub litter, artificially enriched in 15N, was offered in experimental plots to the macro-decomposer community. Both the earthworm Lumbricus rubellus and the millipede Cylindrojulus fulviceps fed on dwarf shrub litter as indicated by their increased δ15N signatures, but IsoError analysis indicated a clear preference for grass litter for all macro-decomposer species investigated.Soil δ15N signatures were only marginally affected by the experimental provision of 15N-enriched dwarf shrub litter, whereas litter from other, unlabelled, plants became enriched by the isotopic tracer to some extent. Except for one grass species, plants harvested at the end of the experiment were not enriched in 15N, suggesting that the N-uptake from decomposing litter material by plants on abandoned alpine pastureland is slow. 相似文献
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Lea Middendorf Marion Schmicke Kristian Düngelhoef Erwin Sieverding Heinrich Windhaus Dieter Mischok Dimitri Radko Christian Visscher 《Journal of animal physiology and animal nutrition》2021,105(Z2):70-78
The hepatic lipidosis (HL) in fattening turkeys is a disease has been known for a long time, but the cause and pathogenesis is still not clarified. A recent study reported unexplained high levels of iron in liver tissue of fattening turkeys suffering from HL. In this study, the iron status, possible infectious or inflammatory influences in form of an acute phase reaction and the analysis of fatty acid pattern in liver tissue of turkeys affected by HL were examined. Three cases of HL on three different fattening turkey farms were investigated during the outbreak of the disease. Clinically affected and non-affected animals were subjected to a pathological examination, where the diagnosis HL or non-affected was made. In total, 70 birds were examined (40 with HL, 30 without HL) and blood and liver samples were taken. Additionally, samples from 15 slaughtered birds were taken as a further control group. In liver tissue, the iron content and the content of long-chain fatty acids were determined; in blood samples, ferritin and transferrin were measured. The iron content in liver tissue was more than three times higher for animals with HL than among non-affected animals and the control group. The transferrin levels were lowest for animals with HL, highest in the control group and in between for non-affected animals. The fatty acid pattern in liver tissue of affected animals indicated a shift from polyunsaturated fatty acids to saturated fatty acids and monounsaturated fatty acids compared to the control group and the non-affected animals. Overall, the non-affected animals of a flock affected by HL were similar to the healthy animals of the abattoir. The low acute phase protein levels for animals with HL together with high iron contents could indicate a previous malnutrition/starvation period and/or severe liver damage for those animals suffering from HL. 相似文献
8.
利用酵母双杂交系统在拟南芥cDNA文库中筛选出1个与ABI2有相互作用的未知蛋白质(AC)。在酵母系统中的进一步研究表明,AC与ABI1、ABI2有相互作用,其作用依赖于ABI1、ABI2的PP2C活性。在大肠杆菌中表达和纯化了与预测结果一致的AC蛋白质。构建了真核过量表达载体,转化拟南芥后筛选和鉴定出转基因AC植株。转基因植株的生理性状分析表明,AC基因的过量表达降低了植物对ABA敏感性。研究初步证明AC可能是脱落酸信号传导途径中的1个新信号分子。 相似文献
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Erwin Schimitschek 《Journal of pest science》1970,43(12):190-190
Ohne Zusammenfassung 相似文献