Search results for "STEPPE"
showing 10 items of 71 documents
Molecular barcoding for central-eastern European Crioceris leaf-beetles (Coleoptera: Chrysomelidae)
2011
Abstract Among Crioceris leaf-beetles, the two most widespread species (Crioceris asparagi and C. duodecimpunctata) are serious invasive plant pests, while another two (C. quatuordecimpunctata and C. quinquepunctata) are rare species restricted to steppe-like habitats in Eurasia. The aim of the research was to check the genetic distinctiveness of these four species and develop barcodes for their molecular identification using the mitochondrial Cytochrome Oxidase I (COI) gene and two nuclear markers: Elongation Factor 1-α (EF1-α) and Internal Transcribed Spacer 1 (ITS1). The identification of each species was possible and reliable with the use of COI and ITS1 markers. EF1-α was omitted in an…
Can vegetation provide indications of ancient lake shorelines after more than one hundred years? A case study of Iskander-kul Lake, Tajikistan
2017
Abstract Bioindication is a common approach to assess and evaluate environmental changes over both short or long periods of time. Here we attempt to highlight that vegetation can provide indications of the palaeoshoreline of Lake Iskander-kul, even after at least 150 years. It is an example of a dammed lake that was created by a huge mass rockfall as a result of a strong earthquake during the late Pleistocene. Applying the two way indicator species analysis (TWINSPAN) we found that the shrubby vegetation is the particular one that can still effectively thrive along the palaeoshoreline despite the lake downlift. Using the phi coefficient as a fidelity measure for certain vegetation type, we …
A stepper motor-driven microelectrode positioner
1987
The mechanical elements and the electronic control system from a stepper motor-driven microelectrode positioner is described. The unit embodies a high-precision small step angle hybrid motor. The compact, rugged and totally concentric design of the mechanic, by a spindle mechanism achieves the necessary precision by translating the stepwise rotations of the motor into steps of linear movement. The system takes advantage of commercially available low friction parts such as ball bearings, ball bushings and axles with hardened surfaces. The related electronic control unit is designed around the most recent integrated circuitry which is both sophisticated and economical. Though the described sy…
Effect of the conversion of grassland to spring wheat field on the CO2 emission characteristics in Inner Mongolia, China
2007
Chinese grasslands have undergone great changes in land use in recent decades. Approximately 18.2% of the present arable land in China originated from the cultivation of grassland, but its impact on the carbon cycle has not been fully understood. This study wasconducted insitu for3yearstoassessthecomprehensive effects ofcultivationof temperatesteppe onsoilorganiccarbon(SOC) and soil respiration rates as well as ecosystem respiration. As compared with those in the Stipa baicalensis steppe, the SOC concentrations at depths of 0‐10 and 10‐20 cm in the spring wheat field were found to have decreased by 38.3 and 17.4% respectively from 29.5 and 21.9 g kg � 1 to 18.2 and 18.1 g kg � 1 after a cul…
Phylogeographic patterns of steppe species in Eastern Central Europe: a review and the implications for conservation
2016
The phylogeography of species associated with European steppes and extrazonal xeric grasslands is poorly understood. This paper summarizes the results of recent studies on the phylogeography and conservation genetics of animals (20 taxa of beetles, butterflies, reptiles and rodents) and flowering plants (18 taxa) of such, "steppic" habitats in Eastern Central Europe. Most species show a similar phylogeographic pattern: relatively high genetic similarity within regional groups of populations and moderate-to-high genetic distinctiveness of populations from currently isolated regions located in the studied area. This distinctiveness of populations suggests a survival here during glacial maxima…
Late Aragonian mammal sites of Cuesta del Rey (Duero Basin, Burgos, Spain)
2017
[EN]: The Cuesta del Rey mammal sites located on the NE border of the Duero Basin are of great importance with regard to understand the general biostratigraphy of the basin, because Miocene mammal sites are extremely scarce in this area in comparison with the central part of the basin. The mammals identified in Cuesta del Rey-1 are: Eulipotyphla: cf. Miosorex sp.; Rodentia: Heteroxerus sp., Armantomys cf. tricristatus, Megacricetodon ibericus, Megacricetodon minor-Megacricetodon debruijni, Hispanomys sp. And Democricetodon sp. The Cuesta del Rey-1 rodent assemblage is characteristic of the end of the upper Aragonian (MN 7/8, end of the middle Miocene), equivalent to the local subzone G3 of …
Soil geography and diversity of the European biogeographical regions
2013
For decades, soil geography has beenmainly a qualitative and descriptive discipline. There are nowtechnologies and mathematical tools available that allow formalizing soil geography in more quantitative terms. In this paper, the distribution and diversity of the soils of Europe are analyzed using GIS tools and pedodiversity algorithms. Soil data were taken from the European Soil Database (V2.0) and computed within the spatial framework of the Biogeographical Regions of Europe (BGRE) as defined by the European Environmental Agency (EEA) on the basis of climate and vegetation. The results obtained show the soil assemblages, including dominant soils and endemic and non-endemic soil minorities,…
Festuca valesiacaSchleich. ex Gaudin newly discovered in the Central Apennines (Italy): a further example of steppe relict in the Abruzzo “dry valley…
2019
Festuca valesiaca Schleich. ex Gaudin subsp. valesiaca is acknowledged as one of the most characteristic grasses of the continental grasslands and steppes of Eurasia. In Italy, the species was known almost only from the continental valleys of the Alpine chain (with the exception of two small populations at the northernmost edge of the Apennines). Here, we report on the first confirmed finding of F. valesiaca subsp. valesiaca in the surroundings of the Fucino Basin, Central Apennines. This finding expands by c. 400 km southwards the species’ range in Italy. The identity of the species was first ascertained by means of leaf cross-sections and stomata measurements, and then confirmed by chromo…
Cooling and societal change during the Late Antique Little Ice Age from 536 to around 660 AD
2016
Societal upheaval occurred across Eurasia in the sixth and seventh centuries. Tree-ring reconstructions suggest a period of pronounced cooling during this time associated with several volcanic eruptions. Climatic changes during the first half of the Common Era have been suggested to play a role in societal reorganizations in Europe1,2 and Asia3,4. In particular, the sixth century coincides with rising and falling civilizations1,2,3,4,5,6, pandemics7,8, human migration and political turmoil8,9,10,11,12,13. Our understanding of the magnitude and spatial extent as well as the possible causes and concurrences of climate change during this period is, however, still limited. Here we use tree-ring…
Genomic transformation and social organization during the Copper Age–Bronze Age transition in southern Iberia
2021
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