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Background: Studying the growth and developmental mechanisms of steppe (Brandt's) voles is important for biological control and protection of steppe ecology. In this paper, preliminary biological experiments' data showed that the mortality of Brandt's vole increased after retinoic acid treatment. Methods: LPH inhibitor, retinoic acid, quercetin and DMSO (Standard treatment concentration 10mg/ml) were given them through oral with the help of Animal oral gavage feeding needles. The hind legs muscles of surviving Brandt's voles were collected for transcriptomic analysis. Result: A total of 4047 and 2251 up- and down-regulated transcripts, respectively, were observed upon retinoic acid treatment compared to the DMSO (control) treatment. Transcriptomic changes were enriched significantly in 31 KEGG pathways, most of which were involved in sugar metabolism, particularly for fructose and mannose (ko00051), protein digestion and absorption (ko04974), phenylalanine metabolism (ko00360), tyrosine metabolism (ko00350) and the PI3K-Akt signaling pathway (ko04151), which is related to growth and development. A total of 114 differentially expressed genes were screened as candidate genes according to the enrichment results, including c-Jun N-terminal kinase and tubulin epsilon chain verified by RT-PCR. Ultimately, we proposed a preliminary regulatory molecular mechanism of retinoic acid relevant to mouse development and death. [ABSTRACT FROM AUTHOR]

The research is aimed at studying the species composition, dynamics of the number and harmfulness of dominant pests, which is extremely important for the development and improvement of elements of the onion protection system. After all, the analysis of literature sources showed insufficient information about the distribution and harmfulness of the main phytophages under modern conditions of growing onions in the Right Bank Forest-Steppe of Ukraine. We conducted the monitoring of the phytosanitary condition of onion crops during 2017-2020 and determined the species composition of dominant phytophages. We studied the complex of soil pests: larvae of Melolontha sp., the population density of which over the years of research was 0.8-2.5 specimens/m2, larvae of Elateridae sp., or click beetles (wireworms) - 0.9-2.2 specimens/m2 and Gryllotalpa gryllotalpa L. - 2.5 specimens/m2. Dominant species of phytophages in onion crops included onion fly (Delia Antigua Mg.), onion thrips (Trips tabaci Lind.), and Ceuthorrhynchus jakovlevi Schultze. The four most vulnerable phases of growth and development of onions before colonization and damage by major phytophages were identified: 1) phase of leaf development (a primary shoot) (BBCH 1-19); 2) phase of the beginning of thickening of leaf base - bulb formation (BBCH 41-43); 3) phase of bulb formation - beginning of leaf splitting (BBCH 45-47); 4) phase of the completion of growth and development (state of physiological rest) (BBCH 48-49). [ABSTRACT FROM AUTHOR]

This article studies the use of livestock dung in the social and ecological context of pastoralism in the Tyva Republic, Inner Asia. In steppe ecologies, livestock dung, depending on its (mis)management, can be a valuable resource or a threat to animals' health and herders' well-being. Its use is embedded in the relationships between herder-livestock communities and landscapes, which are sentient and superordinate. Utilizing dung for household needs is simultaneously a form of care for livestock and a method of balancing the relationship with sentient homelands. [ABSTRACT FROM AUTHOR]

The Siberian mammoth steppe ecosystem changed dramatically with the disappearance of large grazers in the Holocene. The concept of Pleistocene rewilding is based on the idea that large herbivore grazing significantly alters plant communities and can be employed to recreate lost ecosystems. On the other hand, modern rangeland ecology emphasizes the often overriding importance of harsh climates. We visited two rewilding projects and three rangeland regions, sampling a total of 210 vegetation relevés in steppe and surrounding vegetation (grasslands, shrublands and forests) along an extensive climatic gradient across Yakutia, Russia. We analyzed species composition, plant traits, diversity indices and vegetation productivity, using partial canonical correspondence and redundancy analysis. Macroclimate was most important for vegetation composition, and microclimate for the occurrence of extrazonal steppes. Macroclimate and soil conditions mainly determined productivity of vegetation. Bison grazing was responsible for small-scale changes in vegetation through trampling, wallowing and debarking, thus creating more open and disturbed plant communities, soil compaction and xerophytization. However, the magnitude of effects depended on density and type of grazers as well as on interactions with climate and site conditions. Effects of bison grazing were strongest in the continental climate of Central Yakutia, and steppes were generally less affected than meadows. We conclude that contemporary grazing overall has rather limited effects on vegetation in northeastern Siberia. Current rewilding practices are still far from recreating a mammoth steppe, although large herbivores like bison can create more open and drier vegetation and increase nutrient availability in particular in the more continental Central Yakutian Plain. [ABSTRACT FROM AUTHOR]

The ecology of invertebrate steppe species requiring active conservation management has not been explored enough. Stenobothrus eurasius is a characteristic steppe species occurring very frequently in the Siberian and Central Asian grasslands, although on the western edge of its area it is present in small, isolated, endangered relict populations. We examined populations and habitats of St. eurasius in the Pannonian vegetation region to (1) seek predictor variables of its density and (2) explore potentially successful conservation management practices which could be used generally on declining steppe relict species. Our results showed that robust populations of St. eurasius are found in short, edaphic, relict steppe grasslands in which the proportion of coarse sand in the soil is high and which are free of significant disturbance by game (specifically by wild boar). According to our study, the most important approach for the enhancement of declining marginal populations of St. eurasius, existing as an umbrella species of steppe relicts, is to reduce individual numbers of game (mainly wild boar and mouflon) which have increased tenfold regionally in the last few decades (or at least to exclude them from the most vulnerable patches). [ABSTRACT FROM AUTHOR]

• Using the largest available trophic network of a large steppe ecosystem, we tested that steppe trophic networks including migratory species are associated with (i) migratory strategy and (ii) phylogenetic relatedness of interacting species. • We found that (1) a substantial number of links were established by migrant taxa; (2) the phylogenetic signal in network structure was moderate for both consumer and prey nodes; (3) both consumer and prex phylogenies affected modularity, which was modulated by migration strategy; and (4) all species-level graph properties significantly differed between networks including and excluding migratory taxa. • Our findigs provide information for conservation planning by identifying key trophic links in migratory taxa. Evidence is mounting that the structures of trophic networks are governed by migratory movements of interacting species and also by their phylogenetic relationships. Using the largest available trophic network of a large steppe ecosystem, we tested that steppe trophic networks including migratory species are associated with (i) migratory strategy and (ii) phylogenetic relatedness of interacting species: (1) whole graph-level metrics, estimated as modularity, and (2) species-level network metrics, measured as node degree (number of interacting partners), and centrality metrics. We found that (1) a substantial number of links were established by migrant taxa; (2) the phylogenetic signal in network structure was moderate for both consumer and prey nodes; (3) both consumer and prex phylogenies affected modularity, which was modulated by migration strategy; and (4) all species-level graph properties significantly differed between networks including and excluding migratory taxa. In sum, here we show that the structure of steppe trophic networks is primarily governed by migratory strategies and to a lesser extent, by phylogenetic relatedness, using the largest available food web representative for steppe ecology and migration biology. [ABSTRACT FROM AUTHOR]

Steppe‐tundra is considered to have been a dominant ecosystem across northern Eurasia during the Last Glacial Maximum. As the fossil record is insufficient for understanding the ecology of this vanished ecosystem, modern analogues have been sought, especially in Beringia. However, Beringian ecosystems are probably not the best analogues for more southern variants of the full‐glacial steppe‐tundra because they lack many plant and animal species of temperate steppes found in the full‐glacial fossil record from various areas of Europe and Siberia. We present new data on flora, land snails and mammals and characterize the ecology of a close modern analogue of the full‐glacial steppe‐tundra ecosystem in the southeastern Russian Altai Mountains, southern Siberia. The Altaian steppe‐tundra is a landscape mosaic of different habitat types including steppe, mesic and wet grasslands, shrubby tundra, riparian scrub, and patches of open woodland at moister sites. Habitat distribution, species diversity, primary productivity and nutrient content in plant biomass reflect precipitation patterns across a broader area and the topography‐dependent distribution of soil moisture across smaller landscape sections. Plant and snail species considered as glacial relicts occur in most habitats of the Altaian steppe‐tundra, but snails avoid the driest types of steppe. A diverse community of mammals, including many species typical of the full‐glacial ecosystems, also occurs there. Insights from the Altaian steppe‐tundra suggest that the full‐glacial steppe‐tundra was a heterogeneous mosaic of different habitats depending on landscape‐scale moisture gradients. Primary productivity of this habitat mosaic combined with shallow snow cover that facilitated winter grazing was sufficient to sustain rich communities of large herbivores. [ABSTRACT FROM AUTHOR]

The multi-layered settlement of Turganik in the Tok River valley (steppe region west of the Urals) has been studied using paleopedological and microbiomorphical methods. Early humans lived in the settlement during the Eneolithic epoch (the fifth millennium BC) and in the Early Bronze Age (the fourth millennium BC). The cultural layers attributable to the Atlantic period of the Holocene developed under conditions of a rather dry climate, with the landscapes being dominated by the grass and herb steppe. The settlement area was above the flood water level and was suitable for habitation. The soils in its vicinity were Kastanozems (Endosalic Protosodic). The final stages of the cultural layer formation bear traces of strong (though short-term) floods, with the deposits of the latter partly concealed traces of the preceding long-term arid phase. Maximum aridity was during the final interval of the Atlantic period. The Subboreal and Subatlantic periods were noted for meadow-chernozem soil formation (Luvic Chernozems [Stagnic]) and an increasing proportion of arboreal species in the pollen assemblages. Some phytoliths of aquatic plants were found in the assemblages dominated by those of meadow grasses. The climate was more humid and cool, although short episodes of aridity were possible. [ABSTRACT FROM AUTHOR]

Ukraine has maintained its position as leading producer of sunflower seeds in the world for the past decade. Concerning diet, higher oleic acids are ideal. Sunflower (Helianthus annuus L.) hybrids have high genetic potential for seed yield above 5 t/ha and oil content in seed greater than 50%. Yet, environmental factors seems to limit current sunflower yields to the production range of 1.5-3.0 t/ha. A three years field experiment was conducted in the Left-Bank Forest-Steppe of Ukraine (Latitude: 49.6; Longitude: 34.9; altitude 113 m) to assess the influence of seven different foliar applications of fertilizers and plant growth regulators (control; Sol Bor + Basfoliar 6-12-6; Basfoliar 6-12-6; Wuxal Bio Aminoplant + Wuxal Boron; Wuxal Boron; Spectrum Askorist + Spectrum B + Mo; Spectrum B + Mo) on productivity and quality of five new high oleic sunflower hybrids (SY Experto, Antratsyt, ES Ballistic, Oplot, PR64H32). Foliar applications positively influenced all parameters studied (plant height, leaf surface area, number of seeds per head, seed yield, oil content and oleic acid content). The highest average seed yields occurred in the hybrids PR64H32 (3.73 t/ha) and SY Experto (3.69 t/ha) with no significant difference (P<0.05). However, PR64H32 generated a significantly (P<0.05) higher average seed yield than the other hybrids. Except for Wuxal Boron (sprayed twice sequentially) with an average seed yield of 3.53 t/ha, sequential spraying of Wuxal Bio Aminoplant + Wuxal Boron thrice on all hybrids, ensured a significantly higher average seed yield (3.58 t/ha) than the other foliar sprays. Based on foliar sprays, the increase in seed yields ranged from 0.19-0.36 t/ha when compared to control. Foliar sprays also caused increases in oil content between 0.6-1.6% compared to the control with average oil content for the various hybrids fluctuating between 48.4-49.3%. Average oleic acid content ranged from 71.5-83.7% for the investigated hybrids and foliar applications increased the average oleic acid content by 1.8-4.1%. The combined factors of hybrid and foliar applications had the greatest influence on seed yield (share of 62.6%) than hybrid - 29.1%; foliar applications - 6.3%; other factors - 2.0%. [ABSTRACT FROM AUTHOR]

In recent years, the continued loss and fragmentation of steppe has caused decreased ecosystem functions and species losses in insect diversity. In the 2000s, the Chinese government developed a series of national projects, such as the construction of enclosures, to conserve natural ecosystems, including steppe. However, the effects of these enclosures on steppe arthropod community are largely unknown. In the present study, we selected enclosed and low‐grazing regions at eight National Grassland Fixed Monitoring Stations to examine the compositional differences in four insect functional groups and their associated ecological functions. The results showed that diversity significantly differed between the enclosed and low‐grazing regions, with the number of insect families being significantly higher in enclosed regions than in regions with low‐grazing pressure. The responses of the insect community to steppe management also varied among the four groups (herbivores, predators, parasitoids, and pollinators). The abundances of herbivores, predators, and parasitoids were higher in enclosed regions than in low‐grazing regions, while there was no significant difference in pollinators. Additionally, there were no significant differences in the predator/prey ratio between enclosed regions and low‐grazing regions in any of the steppe types. The parasitic wasp/prey ratio was higher in enclosed regions than in low‐grazing regions in meadow steppe and typical steppe, while there were no significant differences between the enclosed and low‐grazing regions in desert steppe and steppe desert. Herbivores were observed to benefit much more from enclosures than predators, parasitoids, and pollinators. Therefore, we recommend low‐grazing should be considered in steppe conservation, which could conserve biodiversity and achieve biocontrol functions of arthropod community. The abundances of herbivores, predators, and parasitoids were higher in enclosed regions than in low‐grazing regions, while there was no significant difference in pollinators. The parasitic wasp/prey ratio was higher in enclosed regions than in low‐grazing regions in meadow steppe and typical steppe, while there were no significant differences between the enclosed and low‐grazing regions in desert steppe and steppe desert. Herbivores were observed to benefit more from enclosures than predators, parasitoids, and pollinators. [ABSTRACT FROM AUTHOR]

Few studies have addressed the potential grazing effects on microclimate, such as surface temperature and moisture, and their feedback effects on grassland function. A continuous, approximately three-year long study was conducted in experimental plots of various grazing intensities, and in situ soil temperature and moisture were measured. The results indicated that grazing significantly altered soil temperature and moisture. Soil temperature increased exponentially with increasing grazing intensity in the warm season due to the removal of aboveground biomass (AGB) and decreased linearly with increasing grazing intensity in the cold season due to decreases in both AGB and wind-blown snow accumulation. Heavy grazing increased soil temperature (10 cm depth) by an average of 2.6 °C from April to October (the largest hourly temperature increase was 8.8 °C), representing a soil warming effect 3.7 times that of global warming. Our findings showed that, compared with ungrazed plots, grazed plots had decreased soil water storage due to less winter snow accumulation, especially in the early growing season (EGS) because of the smaller amount of winter snow accumulation than in ungrazed plots. In the EGS, the average water storage in the 0–100 cm layer of the ungrazed plots was 23.3%, which was 1.3–1.8 times that of the grazed plots. Our results showed that grazing also produced warming and drying effects on grassland soil. The long-term feedback effects of grazing-induced soil warming and drying on the ecosystem might be an important mechanism accelerating the degradation and desertification of these grasslands. [ABSTRACT FROM AUTHOR]