scholarly journals Dynamics of grass stand formation in poplar plantations on different types of reclamations of disturbed lands of Western Donbass

2018 ◽  
Vol 29 (2) ◽  
Author(s):  
O. M. Masiuk

The purpose of our research was to study the long-term dynamics of the herbage cover at different stages of growth and development of poplar plantations on the types of artificial soils of the forest reclamation area. The object of research is flora phytotoxic dumps of «Blagodatna» coal mine, where imported substrates such as sand-clay, clay loam, red-brown earth and humic soil in various combination were applied to create reclamations layer on the surface of the mine dumps (Dnipropetrovsk region, Pavlograd region).  Type 1: 30 cm of soil mass of typical chernozem (SMTC), 50 cm of red-brown earth, 80 cm of alluvial sand-clay and sand, and deeper there is the coal mine  solid; type 2: 30 cm of SMTC, 80 cm of sand, and mine solid deeper; type 3: 30 cm of SMTC, 60 cm of alluvial sand-clay, 60 cm of clay, and deeper there is mine solid; type 4: 40 cm of SMTC, 30 cm of red-brown earth, 40 cm of sand and mine solid deeper; type 5: 55 cm of alluvial sand-clay, deeper there is mine solid. Stationary observations were carried out in poplar plantations of 8-, 16-, 27- and 34-year-old age on permanent trial plots. They were presented with a black poplar and seven hybrid poplars. The research has established that climatic conditions, influence of surrounding phytocenoses of undisturbed lands, inheritance by pedozems of seed material of grass plants with a fertile layer of the soil set the direction of succession on the way of formation of zonal herbal group. The long-term growth of the role of the arid element indicates the formation of a structure close to the zonal flora. The formation of the flora of technical soils in poplar plantations occurs in four stages: the first is pioneer plant communities, which begins with the completion of the technical phase of reclamation and confined to the stages of forest formation; the second is a simple grouping that is associated with the development of the stand until the closure of canopy and inter-row soil cultivation; the third is a complex grouping that is fraught with pole wood stage of stand development and partial getting sparse; the fourth in our studies, is partially closed when gradually tree plants disappear and their influence disappears. In addition to the influence of tree vegetation, its age and stage of development, the formation of lower layers of biogeocenoses is significantly influenced by the conditions stipulated by the stratigraphy and the power of artificial substrates, as well as the elements of the landscape, both created initially and formed as a result of the fragmentary subsidence of the dump territory. These factors, depending on their dynamic changes, regulate correlation between various groups of biomorphs, climamorphs, trofomorphs, hygromorphs, heliomorph and zenomorphs in the grass cover. Created forest vegetation conditions on the plateau and the upper third of the dump do not meet the needs of hybrid poplars under conditions of acute shortage of moisture, which are characteristic of the steppe zone. Fast-growing poplar hybrids can be used as a pioneer culture up to 15–20 years of age.

2008 ◽  
pp. 70-83 ◽  
Author(s):  
E. Bukhvald

Transformations in the sphere of federal relations concern the most important directions of the reforming processes in the country. However, not all proposed and actually developing components of the federal reform seem well-argued and corresponding to long-term, strategic interests of the Russian statehood. The basic course of reform should meet the objective requirements of further decentralization of governing economic and social processes and the need to ensure strengthening the responsibility of RF subjects’ executive bodies and local self-management for steady social and economic development of their territories. The solution of these problems calls for a new model of federal policy of regional development, specification of some important components of the municipal reform as well as inserting certain amendments into the system of intergovernmental fiscal relations in order to stir up their stimulating function.


2001 ◽  
Vol 6 (2) ◽  
pp. 3-14 ◽  
Author(s):  
R. Baronas ◽  
F. Ivanauskas ◽  
I. Juodeikienė ◽  
A. Kajalavičius

A model of moisture movement in wood is presented in this paper in a two-dimensional-in-space formulation. The finite-difference technique has been used in order to obtain the solution of the problem. The model was applied to predict the moisture content in sawn boards from pine during long term storage under outdoor climatic conditions. The satisfactory agreement between the numerical solution and experimental data was obtained.


Author(s):  
Laima TAPARAUSKIENĖ ◽  
Veronika LUKŠEVIČIŪTĖ

This study provides the analysis of drought conditions of vegetation period in 1982-2014 year in two Lithuanian regions: Kaunas and Telšiai. To identify drought conditions the Standardized Precipitation Index (SPI) was applied. SPI was calculated using the long-term precipitation record of 1982–2014 with in-situ meteorological data. Calculation step of SPI was taken 1 month considering only vegetation period (May, June, July, August, September). The purpose of investigation was to evaluate the humidity/aridity of vegetation period and find out the probability of droughts occurrence under Lithuanian climatic conditions. It was found out that according SPI results droughts occurred in 14.5 % of all months in Kaunas region and in 15.8 % in Telšiai region. Wet periods in Kaunas region occurred in 15.8 %, and in Telšiai region occurrence of wet periods was – 18.8 % from all evaluated months. According SPI evaluation near normal were 69.7 % of total months during period of investigation in Kaunas and respectively – 65.5 % in Telšiai. The probability for extremely dry period under Lithuania climatic conditions are pretty low – 3.0 % in middle Lithuania and 2.4 % in western part of Lithuania.


Author(s):  
О. V. Levakova ◽  
L. М. Eroshenko ◽  
А. N. Eroshenko

The article presents and analyzes data of competitive varietal testing of promising varieties and lines of spring barley for yield and brewing qualities. Field studies were conducted in 2014–2017 on dark gray forest heavy loam soil. Agrochemical parameters are total nitrogen – 0.24%, humus content in a layer of 0-40 cm (according to Tyurin) – 5.19%, hydrolysis nitrogen – 123.5 mg / kg, salt extract pH – 4.92 mg-eq / 100g; labile phosphorus - 34.6 mg / 100g, labile potassium – 20.0 mg / 100g. The forerunner is winter wheat. Meteorological conditions in the years of research differed from each other and from the average long-term value. Barley samples were assessed by the protein content in the grain (GOST 10846-91), extract content (GOST 12130-77), weight 1000 grains (GOST 10842-89). Ecological plasticity was determined by the method proposed by E.D. Nettevich, A.I. Morgunov and M.I. Maksimenko, stability index (Ľ) by A. A. Gryaznov, indicator of stability level (Puss) by E. D. Nettevich and A. I. Morgunov. The main measure for assessing quality indicators is protein content. Many other biochemical and technological features of grain depend on its level. The experimental data convincingly testify to the significant influence of the soil and climatic conditions on the yield and, especially, on the brewing qualities of barley in the conditions of the Central Region of the Nonchernozem Zone. According to the studied traits, new valuable varieties Nadezhny, Sir, Noble and selection lines 141 / 1-09 h 746, 23 / 1-10 h 784, distinguished by high adaptability and resistance to adverse environmental factors, have been identified.


2019 ◽  
Vol 25 (1) ◽  
pp. 57-63 ◽  
Author(s):  
Clara Yzet ◽  
Stacy S. Tse ◽  
Maia Kayal ◽  
Robert Hirten ◽  
Jean-Frédéric Colombel

The emergence of biologic therapies has revolutionized the management of inflammatory bowel disease (IBD) by halting disease progression, increasing remission rates and improving long-term clinical outcomes. Despite these well-described benefits, many patients are reluctant to commence therapy due to drug safety concerns. Adverse events can be detected at each stage of drug development and during the post-marketing period. In this article, we review how to best assess the safety parameters of new IBD medications, from the earliest stage of development to population-based registries, with a focus on the special populations often excluded from the evaluation process.


Soil Systems ◽  
2020 ◽  
Vol 5 (1) ◽  
pp. 3
Author(s):  
David Singer ◽  
Elizabeth Herndon ◽  
Laura Zemanek ◽  
Kortney Cole ◽  
Tyler Sanda ◽  
...  

Coal mine spoil is widespread in US coal mining regions, and the potential long-term leaching of toxic metal(loid)s is a significant and underappreciated issue. This study aimed to determine the flux of contaminants from historic mine coal spoil at a field site located in Appalachian Ohio (USA) and link pore water composition and solid-phase composition to the weathering reaction stages within the soils. The overall mineralogical and microbial community composition indicates that despite very different soil formation pathways, soils developing on historic coal mine spoil and an undisturbed soil are currently dominated by similar mineral weathering reactions. Both soils contained pyrite coated with clays and secondary oxide minerals. However, mine spoil soil contained abundant residual coal, with abundant Fe- and Mn- (oxy)hydroxides. These secondary phases likely control and mitigate trace metal (Cu, Ni, and Zn) transport from the soils. While Mn was highly mobile in Mn-enriched soils, Fe and Al mobility may be more controlled by dissolved organic carbon dynamics than mineral abundance. There is also likely an underappreciated risk of Mn transport from coal mine spoil, and that mine spoil soils could become a major source of metals if local biogeochemical conditions change.


1990 ◽  
Vol 70 (4) ◽  
pp. 1071-1080 ◽  
Author(s):  
LUCIUS BELZILE

For five years, the effect of cultivars and vegetative stage of cutting were measured on red clover (Trifolium pratense L.) seed production. The first group of cultivars included Hungaropoli, Ottawa and Lakeland harvested in 1981 and 1982. The second group included Arlington, Florex and Prosper I harvested in 1984, 1985 and 1987. The total annual seed yield differed within cultivars and the highest seed yield was obtained with Hungaropoly and Florex. In the first cultivar group, the tetraploid Hungaropoly obtained a kernel weight higher than the diploids Lakeland and Ottawa. In the second group of cultivars, all diploids, Arlington yielded the highest kernel weight. The percentage of seed germination of Hungaropoly was higher than Lakeland and Ottawa while for Florex it was slightly higher than Arlington and Prosper I. A prior vegetative cutting is essential for good seed yield. In the absence of vegetative cutting seed weight seemed improved. The stage of development at which vegetative cutting is done has little influence on percentage seed germination. These results have shown that despite the strong effect of climatic conditions on seed production, the choice of the optimum stage for vegetative cutting and a well adapted cultivar are important aspects in successful seed production.Key words: Red clover, seed production, cultivar, stage of cutting


Author(s):  
Biruta Jansone ◽  
Sarmīte Rancāne ◽  
Pēteris Bērziņš ◽  
Aldis Jansons

Abstract The aim of this work was to develop a red clover variety adapted to agro-climatic conditions of Latvia, suitable for different requirements of forage producers, resistant to most widespread diseases and producing high seed yield annually. Medium late ripening diploid red clover variety ‘Jancis’ was created at the LLU Research Institute of Agriculture in long-term work carried out since 1985. After free pollination of best samples of red clover collections from the VIR (St. Petersburg), individual and family selection among hybrids were carried out for approximately 20 years. Finally, best breeding line Nr. 43047 was registered as a variety ‘Jancis’. The variety is characterised by good winter hardiness, high dry matter yield (10-12 t·ha-1) and good persistence in the sward - up to 3-4 years. The variety is characterised by a long stem (90-110 cm) with 8-9 internodes, dark green leaves with a distinctive brighter picture, medium length and width of medial leaflet, and bright pink flower heads. ‘Jancis’ has stable annual seed yield in the conditions of Latvia; under favourable conditions reaching 500- 600 kg·ha-1 seeds. Since 2010, the variety ‘Jancis’ has been included in the common Latvian and EU Plant Variety Catalogue.


2009 ◽  
Vol 276 (1663) ◽  
pp. 1845-1854 ◽  
Author(s):  
Arild Husby ◽  
Loeske E.B. Kruuk ◽  
Marcel E. Visser

For multiple-brooded species, the number of reproductive events per year is a major determinant of an individual's fitness. Where multiple brooding is facultative, its occurrence is likely to change with environmental conditions, and, as a consequence, the current rates of environmental change could have substantial impacts on breeding patterns. Here we examine temporal population-level trends in the proportion of female great tits ( Parus major ) producing two clutches per year (‘double brooding’) in four long-term study populations in The Netherlands, and show that the proportion of females that double brood has declined in all populations, with the strongest decline taking place in the last 30 years of the study. For one of the populations, for which we have data on caterpillar abundance, we show that the probability that a female produces a second clutch was related to the timing of her first clutch relative to the peak in caterpillar abundance, and that the probability of double brooding declined over the study period. We further show that the number of recruits from the second clutch decreased significantly over the period 1973–2004 in all populations. Our results indicate that adjustment to changing climatic conditions may involve shifts in life-history traits other than simply the timing of breeding.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sarah Pederzani ◽  
Vera Aldeias ◽  
Harold L. Dibble ◽  
Paul Goldberg ◽  
Jean-Jacques Hublin ◽  
...  

AbstractExploring the role of changing climates in human evolution is currently impeded by a scarcity of climatic information at the same temporal scale as the human behaviors documented in archaeological sites. This is mainly caused by high uncertainties in the chronometric dates used to correlate long-term climatic records with archaeological deposits. One solution is to generate climatic data directly from archaeological materials representing human behavior. Here we use oxygen isotope measurements of Bos/Bison tooth enamel to reconstruct summer and winter temperatures in the Late Pleistocene when Neandertals were using the site of La Ferrassie. Our results indicate that, despite the generally cold conditions of the broader period and despite direct evidence for cold features in certain sediments at the site, Neandertals used the site predominantly when climatic conditions were mild, similar to conditions in modern day France. We suggest that due to millennial scale climate variability, the periods of human activity and their climatic characteristics may not be representative of average conditions inferred from chronological correlations with long-term climatic records. These results highlight the importance of using direct routes, such as the high-resolution archives in tooth enamel from anthropogenically accumulated faunal assemblages, to establish climatic conditions at a human scale.


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