共查询到20条相似文献,搜索用时 0 毫秒
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GILLIAM AG 《Public Health Reports》1948,63(21):677-684
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DEGA W 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1952,7(31-32):975-987
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Diet of wolvesCanis lupus Linnaeus, 1758 in Latvia was studied from 1997 to 2001 based on 302 scats and 107 stomachs. Wild ungulates (cervids and wild
boarSus scrofa) and beaverCastor fiber were the dominant prey. Cervids were found in 50% of samples (62% biomass), wild boar in 25% (21% biomass), beavers in 14%
(12% biomass). Wolves selected for wild boar, especially in winter when its ratio in the diet increased to 34% from 20% in
summer. It was a more common prey species in the east of the country. The ratio of beavers, small rodents and plant food was
higher in summer, which resulted in a broader food niche in summer than in winter (B = 2.53 versus 1.81, respectively). The
role of domestic animals in the wolf diet was minimal except for winter when they were consumed as carrion (13%). More than
1/3of all stomachs investigated were empty. The average weight of stomach contents was 972.8 g. The importance of the beaver
as an alternative prey is discussed. We conclude that wolves in Latvia prey mainly on wild animals and conflicts with livestock
owners are only occasional and/or local. 相似文献
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Dace Dzenovska 《Ethnos》2013,78(4):496-525
My paper is a critical analysis of anti-racist and tolerance promotion initiatives in Latvia. First, I trace the historical and geopolitical conditions that enable the emergence of two discursive positions that are central to arguments about racism – that of liberally inclined tolerance activists and that of Latvians with politically objectionable nationalist sensibilities. Subsequently, I argue that, plagued by developmentalist thinking, anti-racist and tolerance promotion initiatives fail in their analysis of contemporary racism. They posit backward attitudes as the main hindrance to the eradication of racism and displace racism as a constitutive feature of modern political forms onto individual and collective sensibilities. Instead of the fast track diagnosis of racism that animates liberal anti-racism, I suggest that an analysis of racism should integrate attention to the common elements of modern racism across political regimes and the historical particularities that shape public and political subjectivities in concrete places. 相似文献
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A. Piterans 《Nordic Journal of Botany》1992,12(5):505-506
A review of H. Skuja's phycological research carried out in Latvia during the period 1924–1944. It is due to his research that the number of algal species identified in Latvia increased from 200 to 2300. 50 species and varieties, and 9 genera were described by him as new. 相似文献
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Normunds Prieditis 《Folia Geobotanica》1993,28(3):261-277
The black alder (Alnus glutinosa (L.)Gaertn.) stands occupy 2.5% of the forest area in Latvia. The majority of its communities lie on peatlands; they have been studied in the whole of latvia using the Braun-Blanquet approach. One hundred and fifty alder dominated relevés selected from 334 forest areas have been analysed. Three associations (Carici elongatae-Alnetum, Sphagno squarrosi-Alnetum, andCircaeo-Alnetum), one with four subassociations have been recognized; these belong to the Eurosiberian alder swamps (cl.Alnetea glutinosae) and the European broad-leaved forests (cl.Querco-Fagetea). The phytosociological structure, distribution in Latvia and floristic features of these communities are reported. Results are compared with similar communities in the Baltic Sea states and neighbouring countries. 相似文献
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BROOKS DM 《Proceedings of the Royal Society of Medicine》1954,47(4):265-271
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Treikale O Priekule I Javoisha B Lazareva L 《Communications in agricultural and applied biological sciences》2010,75(4):627-634
Fusarium head blight (FHB) of wheat has, in recent years, been a very important worldwide disease in intensive growing of cereal. The objectives of this study were to evaluate the occurrence of FHB in wheat in Latvia and to identify the Fusarium species involved. This paper describes the distribution of Fusarium species that were isolated from samples representing winter and spring wheat varieties in Latvia, identified both by the classical morphological analyses of J. Leslie and B. Summerell (2006) and by PCR. The FHB incidence range in winter wheat was 1-20%, in spring wheat was 1-42%. The most significant factor affecting the incidence of fusarial head blight in wheat in Latvia was heightened temperature at the time of an thesis of wheat. In winter wheat 9 Fusarium species caused FHB: F. culmorum, F. avenaceum, F. graminearum, F. equiseti, F. poae, F. oxysporum, F. cerealis, F. sporotrichoides and F. verticillioides were identified by morphological characterization, and 5 were confirmed by PCR-analysis. After experience of 5 years, it can be concluded that the most frequent in winter wheat were F. poae and F. culmorum. In spring wheat from F. culmorum was dominant among 8 Fusarium species. Among 13 varieties of spring wheat, three were sensitive ('Chamsin', 'W 166', 'Azurite') and one was resistant ('Granny') to FHB in conditions of high natural infection in 2009. The monitoring surveys demonstrate a significant presence of FHB in spring wheat in conditions of heightened temperature at the time of flowering in Latvia. 相似文献