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1.
Zusammenfassung In einem Vorkommen des Dünnschnäbligen Tannenhähers an der Küste des Ochotskischen Meeres im Fernen Osten Sibiriens wurde das Ernten und Verstecken von Samen aus den Zapfen der Zwergzirbelkiefer (Pinus pumila) untersucht. Der Inhalt von durchschnittlich 2,8 Zapfen, das sind etwa 80 Samen, wurde in der gefüllten Kehltasche transportiert und auf eine Anzahl unter niedriger Zwergstrauchvegetation gelegener Bodenverstecke verteilt. Die Verstecke wurden in annähernd linearer Anordnung ohne Bevorzugung einer bestimmten Himmelsrichtung angelegt. Die Versteckserien enthielten im Median 79, maximal mehr als 120 Samen, das Einzelversteck durchschnittlich 19,6 Samen. Das Ernten und Leeren eines Zapfens geschah im Schnitt innerhalb von 47 s. Für das Verstecken einer Füllung des Kehlsacks benötigten die Vögel ca. 170 s. Für das gesamte Beschaffen und Verstecken eines einzelnen Kiefernsamens errechnet sich ein durchschnittlicher Zeitbedarf von 3,26 s. Nach 20 Tagen war der Zapfenvorrat in der lokalen Kiefernpopulation erschöpft. Jeder Häher hat nach den Hochrechnungen bis zu 100.000 Samen vergraben.
Harvesting and caching capacities of Thin-billed Nutcrackers in the Russian Far East
Summary At the Ochotskian sea coast Thin-billed Eurasian Nutcrackers (Nucifraga caryocatactes macrorhynchos) harvested seeds of ripe cones of the brush pinePinus pumila in late summer. The mean number of seeds carried in their sublingual pouch was 80, which respresents the harvestable contents of 2.8 cones. These were distributed in an average of 5 caches, exclusively in the soil under low tundra vegetation. Caches were organized in nearly straight lines. Series contained a mean of 82.7 seeds, single caches a mean of 19.6 seeds. Plucking one cone and harvesting its seeds took 47 seconds on average. The caching of a complete pouchful took on average 123.4 seconds. The time invested for harvesting and caching one single seed was calculated at 3.26 seconds. Within three weeks in July, an average individual bird was calculated to have cached a total of up to 100,000 seeds.
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3.
The knapweed nematode, Subanguina picridis, forms galls on the leaves, stems, and root collar of Russian knapweed, Acroptilon repens. After being revived from a dormant, cryptobiotic state, second-stage juveniles required at least 1 month in a free-living state before becoming infective. Galls were induced on relatively slow-growing host plants that retained their apical meristems at or near the soil surface for 2-5 weeks. Galls developed extensive areas of nutritive tissue. The nematode was introduced from the Soviet Union and released in Canada for the biological control of Russian knapweed.  相似文献   
4.
Early Permian facies and paleogeography of the Southeastern Russian craton   总被引:1,自引:0,他引:1  
Summary During the Early Permian deep-water basins existed in the southeastern part of the Russian craton. North and west of the Cis-Ural foredeep and the Precaspian depression (micro-ocean) carbonate platforms were formed on a shallow-marine shelf during the Asselian, Sakmarian and Early Artinskian. Reefs developed on the margin of these platforms along the slopes of the Cis-Ural foredeep and the Precaspian depression. The reefs shifted platform ward in the eastern areas, due to the tectonic subsidence of the platform margin and at the same time, prograded basinward in the south. Movements of continental blocks from the south during the Late Artinskian and Kungurian caused the separation of the Early Permian basin of the Russian craton from the Palaeo-Tethys, followed by evaporite sedimentation in the restricted basins. The existence of source rocks (bituminous deep-water sediments), thick reservoir rocks (limestones and dolostones), evaporitic seals and structural as well as stratigraphic traps are responsible for large productive gas and oil fields (e.g., Orenburg field), some of which are distinctly associated with reef carbonates.  相似文献   
5.
The influence of temperature, shoot age, and medium on gall induction by Subanguina picridis on Russian knapweed (Acroptilon repens) was examined in vitro. The optimal temperature for gall formation was 20 C. Gall induction was delayed as the temperature decreased, and decreased as shoot age increased. Bud primordia (0-day-old shoots and 5-day-old shoots) with an average length of 4.2 mm and 7.9 mm were the most suitable tissues for nematode development and gall formation. Gall formation was more effective on B5G medium than on MSG. Young shoots under slow growth were most suitable for mass rearing of S. picridis.  相似文献   
6.
K.L. Stevens 《Phytochemistry》1982,21(5):1093-1098
Six sesquiterpene lactones have been isolated and characterized from Centaurea repens. They are identified as cynaropicrin, repin, janerin, aguerin B, repdiolide and epoxyrepdiolide.  相似文献   
7.
Results of the tree-ring dating of samples from the three Russian settlements of the 18th century (Bjornbeinflyene, Palffyodden, and Schonningholmane) at Svalbard are presented. The present study is a development of a previous work (Chochorowski and Krapiec, 2017). These stations were discovered during excavations conducted by the Polish archaeological expedition of Jagiellonian University in the Sorkappland and Hornsund fjord regions of the Svalbard Archipelago. In total, 5 non-dated samples of the previous work were reanalyzed for these sites: Bjornbeinflyene (2 samples), Palffyodden (1 sample), Schonningholmane (1 sample) and relics from the landing site on the Torrflya coast (1 sample). All samples from these settlements are constructional elements of dwellings, appearing to be prefabricates brought from the continent, and only one of them is a driftwood timber. These floating chronologies were cross-dated against more than 200 master tree-ring chronologies from the Arctic coast, including as well our own data. Cross-dating was performed by CORINA software which includes t-values calculated with different detrending options. As a result, it was possible to successfully date and determine the place of origin of these samples. Results obtained do not contradict the data of radiocarbon and archaeological dating and indicate the possible use of wood from the territories of the White and Kara Sea basins as a building material for the Russian Pomor settlements in Svalbard.  相似文献   
8.
Introduction. The Kuril Islands Chain demarcates the boundary between the circumpolar and East Asian floras in the amphi-Pacific and is a trans-Oceanic migration route from warm-temperate insular East Asia to north-east Asia and Beringia. This paper reviews the flora of the northern part of Iturup Island in regards to its bryogeography and taxonomic diversity, as well as its relative position among other bryophyte floras of north-east and East Asia.

Methods. The paper uses morphological methods to identify the species composition and detrended correspondence analysis to identify the position of the northern Iturup Island in the system of local floras of the eastern, extra-tropical, Pacific.

Key results. The flora is closely related to the bryophyte floras of the southern Kurils and Hokkaido Island, but has been found to be distinctly distant from the ‘true’ cool-temperate East Asian floras, as well as from the boreal and hemiarctic floras of north-east Asia. Instead, the floras of the south Kurils and northern Hokkaido Island belong to a peculiar intermediate phytogeographic province that cannot be unambiguously placed in either the East Asian or circumboreal floristic regions. The hemiboreal character of the bryophyte flora of northern Iturup Island is in contrast to the general appearance of many of the dominant vegetation communities on the island, which are more characteristic of the hemiarctic.

Conclusion. There is no robust evidence to refer the bryophyte flora of northern Iturup either to the circumboreal or East Asian Floristic Region, the flora belongs to a unique intermediate province between the two regions.  相似文献   
9.
The nominal family group taxa of the Ephemeroptera are listed along with their authors, dates of publication and bibliographic references.  相似文献   
10.
Market-based incentives are a new approach to direct fisheries toward greater sustainability. The Marine Stewardship Council (MSC) is the leading certification scheme for wild capture fisheries. Four Russian fisheries were certified from 2010 to 2014. Despite a slow start, the Russian fishery assessments have gone more quickly, received less public criticism, and scored better over time. Consensus is emerging that the Russian system for fisheries management fulfills the MSC requirements.  相似文献   
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