scholarly journals Dynamics of Siberian pine (Pinus sibirica) seed production in Novosibirsk region

2020 ◽  
Vol 24 (6) ◽  
pp. 44-50
Author(s):  
O.V. Parkina ◽  
◽  
R.A. Tretyakova ◽  
G.A. Galitskaya ◽  
◽  
...  

The results of an analytical review and evaluation of long-term experimental data on the dynamics of seed-bearing of Siberian pine in the Novosibirsk region at the objects of the forest seed base in the Iskitim forestry are presented. The analysis of the development of the generative part of the cedar depending on the hydrothermal conditions of the years of study and the individual variability of clones. The data obtained indicate that the growing conditions and humidity, as well as the temperature factor affect the periodicity of seed production. The years that differ in the volume of cedar seed harvesting for the period 2009–2017 are highlighted. Years of mass harvests and crop failures need to be investigated to study the causes of periodicity of fruiting and features of the process of pollination, fertilization and development of cones.

2019 ◽  
Vol 65 (No. 8) ◽  
pp. 291-300
Author(s):  
Nikita Debkov

Under natural conditions, Siberian pine Pinus sibirica begins to produce commercial cone yields of nuts relatively late (after more than 100 years). The aim of this study was to summarise the experience of the directed formation of Siberian pine forests in Siberia. Experimental objects included plots with traditional thinning of varying intensity and frequency as well as chemical treatment. We assessed the parameters of the stand and its seed production dynamics. Only stands with a minimum density (395–435 trees·ha–1) had a normal seed production energy (1.5 or more cones per shoot). Over-dense stands (830–930 trees·ha–1) were characterised by a low seed production energy (two times or more below the threshold value). In all plots, there were Siberian pine trees with absent or unacceptable seed production energy, which should be removed (DBH up to 28 cm). Seed production energy positively correlated with most tree parameters (age, height, diameter, volume, length and width of crown).


Agrology ◽  
2021 ◽  
Vol 4 (3) ◽  
pp. 137-142
Author(s):  
M. Ya. Kyrpa ◽  
N. S. Filipkova

The organization of the sowing material stocks is a necessary condition for stable seed production of any crop. Insurance, reserve, breeding and transi-tional funds are such stocks in corn seed production. Their creation and maintenance largely depend on the economic longev-ity of seeds, which can be formed at the stages of cultivation, harvesting, post-harvest processing and storage of seed. However, the data on the peculiarities of the formation of seed longevity of corn hybrids and their ability to long-term storage are lim-ited. That is why research in this area is considered relevant and important. The results of study of regularities of formation and factors of longevity of corn hybrids seeds of domestic selection are summarized in the executed work. Ecological, technical-technological and varietal factors are formed dur-ing corn cultivation, har-vesting and processing. The greatest dependence is noted on the hydrothermal conditions, start-ing from the stage of cultivation, and then – in the stages after harvesting - the modes of drying and separation of seed. High economic durability is provided under the following conditions: hydro-term coefficient at the level of 0,5–0,7 – for vegetation and 0,3–0,4 – for maturing, dry-ing temperature within 36–400С at humidity of seeds of 20–30%, fractional separation, removal from the seeds mass of the unstable frac-tion containing 18–20% of the total. Some of the factors included a sign of seed size, which is clearly manifested at the stage of long-term storage of seed. Sowing fractions differ significantly in terms of size, including the weight of 1000 seeds and their linear size. The greatest economic durability is inherent in the first and second of all factions. It is recommended to obtain them by calibrating the seeds on separating sieves with round holes with a diameter of 8–10 mm, depending on the hybrids. Prolonged storage is proposed on the basis of a combination of two factors – low humidity and airtight packaging of seeds. This significantly reduces resource costs and extends the economic longevity of corn hybrid seeds to 4–5 years.


2020 ◽  
Vol 73 (1) ◽  
pp. 52-63
Author(s):  
Nikita Debkov ◽  
Victor Sidorenkov ◽  
Elena Sidorenkova ◽  
Vladimir Sedykh

Abstract The article considers the long-term (100 years) dynamics of the forest cover of the southernmost unit of Siberian pine forests on the West Siberian plain. A key feature of forest management is that Siberian pine seeds are a valuable food product and, when cutting forests, this tree species, as a rule, is preserved. The basis of the experimental data was the material of the national forest inventories of 1915, 1974 and 2015 for a total area of 1,420.41 ha. During the period from 1915 to 2015, the forested area changed slightly (96.2 and 94.0%), while the share of Siberian pine stands increased significantly from 48.4 to 58.7%. Grassy Siberian pine forests (32.1%) of optimal age (120–140 years), which are characterised by the best seed productivity and the largest share of Siberian pine in the community (77%), predominate. Basically, human economic activity results in an increase in the area of Siberian pine stands, when deciduous stands with Siberian pine undergrowth are used for fuel and as building material. A decrease in the area of Siberian pine forests occurs mainly under the impact of fires. In the conflagrations of 1915–1920, 7 to 38% of silver birch forests have no Siberian pine undergrowth and are considered long-term secondary communities. In the remaining area, the proportion of Siberian pine undergrowth is 20–30% with a density of 800–1200 seedlings ha−1, which is sufficient for the natural formation of Siberian pine forests.


Life ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 596
Author(s):  
Valentina Crobe ◽  
Alice Ferrari ◽  
Robert Hanner ◽  
Robin W. Leslie ◽  
Dirk Steinke ◽  
...  

Conservation and long-term management plans of marine species need to be based upon the universally recognized key-feature of species identity. This important assignment is particularly challenging in skates (Rajiformes) in which the phenotypic similarity between some taxa and the individual variability in others, hampers accurate species identification. Here, 432 individual skate samples collected from four major ocean areas of the Atlantic were barcoded and taxonomically analysed. A BOLD project ELASMO ATL was implemented with the aim of establishing a new fully available and well curated barcode library containing both biological and molecular information. The evolutionary histories of the 38 skate taxa were estimated with two concatenated mitochondrial markers (COI and NADH2) through Maximum Likelihood and Bayesian inference. New evolutionary lineages within the genus Raja were discovered off Angola, where paleogeographic history coupled with oceanographic discontinuities could have contributed to the establishment of isolated refugia, playing a fundamental role among skates’ speciation events. These data successfully resolved many taxonomic ambiguities, identified cryptic diversity within valid species and demonstrated a highly cohesive monophyletic clustering among the order, laying the background for further inference of evolutionary patterns suitable for addressing management and conservation issues.


Author(s):  
O.V. Mareev ◽  
◽  
G.O. Mareev ◽  
M.E. Gutynina ◽  
D.A. Maksimova ◽  
...  

2019 ◽  
pp. 57-67
Author(s):  
T.M. Tabatskaya ◽  
N.I. Vnukova

A technique for the long-term (up to 27 years) in vitro storage of valuable birch genotypes under normal (25 °C, 2.0 klx, 16-h day and 8-h night) and low temperature (4 °C, 0.5 klx, 6-h day and 18-h night) growing conditions on hormone-free media has been described. The study explored for the first time the influence of different strategies to store the clones of Betula pubescens and B. pendula var. сarelica (6 genotypes) on the regenerative capacity of collection samples, adaptive potential of regenerated plants and plant production by the in vitro and ex vitro techniques. It was established that both storage strategies provided a persistently high survival rate (82-100%) and regenerative capacity of in vitro shoots (the multiplication coefficient of 4.2-6.3 and rhizogenic activity of 90-100%). The clones retained their characteristics of height growth under the in vitro and ex vitro conditions, and demonstrated intraclonal homogeneity and lack of signs of somaclonal variability. The plants showed substantial interspecific differences at the stage of multiplication and transfer to the greenhouse. The highest percentage of acclimated plants (75-98% depending on the clone genotype) was obtained after planting of micro plants straight in the greenhouse, which simplified the technology and made plant production less costly. long-term in vitro storage, birch, species, genotype, micropropagation, ex vitro adaptation, plant material


Author(s):  
David M. Willumsen

The central argument of this book is that voting unity in European legislatures is not primarily the result of the ‘disciplining’ power of the leadership of parliamentary parties, but rather the result of a combination of ideological homogeneity through self-selection into political parties and the calculations of individual legislators about their own long-term benefits. Despite the central role of policy preferences in the subsequent behaviour of legislators, preferences at the level of the individual legislator have been almost entirely neglected in the study of parliaments and legislative behaviour. The book measures these using an until now under-utilized resource: parliamentary surveys. Building on these, the book develops measures of policy incentives of legislators to dissent from their parliamentary parties, and show that preference similarity amongst legislators explains a very substantial proportion of party unity, yet alone cannot explain all of it. Analysing the attitudes of legislators to the demands of party unity, and what drives these attitudes, the book argues that what explains the observed unity (beyond what preference similarity would explain) is the conscious acceptance by MPs that the long-term benefits of belonging to a united party (such as increased influence on legislation, lower transaction costs, and better chances of gaining office) outweigh the short-terms benefits of always voting for their ideal policy outcome. The book buttresses this argument through the analysis of both open-ended survey questions as well as survey questions on the costs and benefits of belonging to a political party in a legislature.


2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 714-715
Author(s):  
Marie Gualtieri

Abstract The recent reauthorization of the Older Americans Act adds language and definitions to current issues facing the aging population. Specifically, Title I includes definitions related to program adaptation and coordination, workforce and long-term care issues, nutrition and social isolation, as well as family caregivers. Different from the last authorization, these definitions span beyond the individual experience to include other entities impacted by an aging society, such as the workforce and families. Overall, the Title I reauthorization seeks to modernize policy to reflect the current influx of the older adult population and its consequences.


2020 ◽  
pp. 030802262097951
Author(s):  
Lizette Norin ◽  
Björn Slaug ◽  
Maria Haak ◽  
Susanne Iwarsson

Introduction Adults with spinal cord injuries are living longer than previously, and a majority are living in ordinary housing in the community. Housing accessibility is important for maintaining independent occupational performance for this population, but knowledge in this area is insufficient. We investigated housing adaptations and current accessibility problems among older adults with long-standing (>10 years) spinal cord injuries. Method Data from home visits among 122 older adults with spinal cord injuries in Sweden were used. Housing adaptations and environmental barriers were descriptively analysed. Findings Kitchens, entrances, and hygiene areas were common locations for housing adaptations and environmental barriers that generated accessibility problems. The most common adaptations were ramps, wheelchair-accessible stovetops, and ceiling-lifts. Wall-mounted cupboards and high shelves (kitchen), inaccessible storage areas (outside the dwelling), and a lack of grab bars (hygiene area) generated the most accessibility problems. Conclusion Despite housing adaptations, there are considerable accessibility problems in the dwellings of older adults with long-standing spinal cord injuries in Sweden, indicating that long-term follow-up of the housing situation of this population is necessary. Focusing on accessible housing as a prerequisite for occupational performance is at the core of occupational therapy, deserving attention on the individual as well as the societal level.


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