scholarly journals Growth trends of spruce in the Orlické hory Mts.

2012 ◽  
Vol 50 (No. 2) ◽  
pp. 67-77 ◽  
Author(s):  
M. Vejpustková ◽  
D. Zahradník ◽  
V. Šrámek ◽  
V. Fadrhonsová

In 2002, height and diameter growth of spruce was investigated in the Orlick&eacute; hory Mts. (the Czech Republic). The aim was to confirm and to quantify a growth increase in stands of different age, and to reveal the relation between growth and climate, and level of nitrogen deposition. Stem analyses of ten sample trees of mature spruce stand (average age 163 years) confirmed a significant increase in height and diameter growth since the mid-eighties of the 20<sup>th</sup> century. Nearly 75% of radial increment variability could be explained by climatic factors. Growth in the last 10 years corresponded well to weather conditions. Analysis of the growth &ndash; nitrogen deposition relationship showed negative correlations, but the results were not statistically significant. Comparison of the height growth curves of young stands (11&ndash;47 years) proved that the younger the stand, the steeper the growth curve. The height of the youngest stands was on average the double of the height of older stands at the same age. The values of the height growth of young stands significantly overreached the yield table values in all the age classes analyzed.

Purpose of this research was to detect influence of climatic change on pine radial increment in stand in the Left-bank Forest-steppe of Ukraine as example 100-years-old stand at State Enterprise 'Kharkiv forest scientific research station’. Methods. Dendrochronological. Method of correlation function and multiple regressions (response function) were used to analyze the influence of climatic factors on tree radial increment. For this purpose computer program RESPO was used. Results. Tree ring series were built and were used for correlation analysis between climatic factors and pine radial increment for two periods: 1960-1988 and 1988-2016.Years of minimum (1933, 1942, 1956, 1972, 1976, 1976, 1987, 1992, 2002, 2006 та 2012) and maximum (1933, 1942, 1956, 1972, 1975, 1976, 1979, 1979, 1979, 1987, 1992, 2002 та 2012) of radial increment were detected. Depressions of pine radial increment were as a result of negative weather conditions: low and high winter and early-spring temperature, droughts during vegetation period. Maximums of radial increments were depended on favorable weather conditions for pine radial growth. Correlation and Response analysis for two periods showed that increase of temperature and precipitation, excluding winter precipitation, changed response of forest ecosystems to climatic change: if in first period (1960-1988) radial increment limited by April temperature and together July temperature positively influenced on radial growth, in second period (1988-2016) June temperature negatively infuenced on radial increment. Slight increase precipitation during vegetation period could not soften impact if high temperature during vegetatation period on tree radial increment. Conclusions. At comparison 1960-1988 and 1988-2016 it was detected that during first period positive influence of summer temperature on radial growth was distinctive and for second period one started to limit increment (negative influence) were detected. Slight increase of precipitation for vegetation period in second period significantly didn’t influence on pine radial growth. In second period increase of winter temperature and number of thaws negatively influenced on soil moisture, decreased of tree ring widths.


1973 ◽  
Vol 3 (4) ◽  
pp. 501-511 ◽  
Author(s):  
John Worrall

Daily height increment of trees was measured throughout two growing seasons as was 2-day radial increment of 212 of the same trees in the second season. The relationships between phenological variables and total growth, and the effect of environment on short term growth were assessed. Inferences taken from the latter data were tested on seedlings under more controlled conditions in the laboratory. The arbitrarily defined dates of initiation and cessation of growth, and the grand period growth rates were read from the growth curves. The respective simple r2 values between these variables and height growth were 0.10, 0.40, and 0.71, and r2 for the multiple regression of height growth and these variables was 0.94; for radial growth these values were 0.07, 0.56, 0.64, and 0.94. Length of the growing season and grand period growth rate were positively correlated. Dates of growth initiation and growth cessation were also positively correlated.Daily height growth varied considerably, depending strongly on temperature and relative humidity. The latter was associated with both a change in growth rate and a physical (nongrowth) change in size. Radial growth varied less, and depended less on environmental conditions. Minimum daily radius occurred several hours after the occurrence of maximum xylem sap tension.In seedlings, dimensional changes were very rapid on change of water stress. Day height growth rate was higher than night growth rate, presumably because of current photosynthate use.


2020 ◽  
Vol 33 (12) ◽  
pp. 1589-1595
Author(s):  
Mariana del Pino ◽  
Virginia Fano ◽  
Paula Adamo

AbstractObjectivesIn general population, there are three phases in the human growth curve: infancy, childhood and puberty, with different main factors involved in their regulation and mathematical models to fit them. Achondroplasia children experience a fast decreasing growth during infancy and an “adolescent growth spurt”; however, there are no longitudinal studies that cover the analysis of the whole post-natal growth. Here we analyse the whole growth curve from infancy to adulthood applying the JPA-2 mathematical model.MethodsTwenty-seven patients, 17 girls and 10 boys with achondroplasia, who reached adult size, were included. Height growth data was collected from birth until adulthood. Individual growth curves were estimated by fitting the JPA-2 model to each individual’s height for age data.ResultsHeight growth velocity curves show that after a period of fast decreasing growth velocity since birth, with a mean of 9.7 cm/year at 1 year old, the growth velocity is stable in late preschool years, with a mean of 4.2 cm/year. In boys, age and peak height velocity in puberty were 13.75 years and 5.08 cm/year and reach a mean adult height of 130.52 cm. In girls, the age and peak height velocity in puberty were 11.1 years and 4.32 cm/year and reach a mean adult height of 119.2 cm.ConclusionsThe study of individual growth curves in achondroplasia children by the JPA-2 model shows the three periods, infancy, childhood and puberty, with a similar shape but lesser in magnitude than general population.


1984 ◽  
Vol 14 (5) ◽  
pp. 731-739 ◽  
Author(s):  
Thomas M. Hinckley ◽  
Hiromi Imoto ◽  
Katharine Lee ◽  
Susan Lacker ◽  
Yasushi Morikawa ◽  
...  

Seven sites ranging from 15 to 135 km from Mount St. Helens were selected to study the impact of air-fall tephra on the growth of Abiesamabilis (Dougl.) Forbes, A. procera Rehd., Pseudotsugamenziesii (Mirb.) Franco, Tsugaheterophylla (Raf.) Sarg., and T. mertensiana (Bong.) Carr. As tephra depth increased, there was a corresponding increase in visible foliar damage and associated decreases in diameter and height growth. Reduction in diameter growth was greater than reduction in height growth. The reduction in diameter growth approached 50% in both trees and saplings of A. amabilis. Growth reduction in true firs was greater than in associated species. This difference was related to their greater capacity for interception and retention of air-fall tephra. Damage to trees, and resulting growth reductions, were due to tephra coverage of both the foliage and the soil. Coverage of the foliage resulted in foliar damage, foliage abscission and reduction of total tree foliar area, and increased fine root mortality. Tephra coverage of the soil had the potential to restrict oxygen diffusion into the soil. However, soil oxygen concentrations less than 10% were measured only once over a 2-year period.


2021 ◽  
pp. 31-37
Author(s):  
R. A. Konuspayev ◽  
◽  
T. Zh. Demesinov ◽  
T. A. Taipov ◽  
◽  
...  

The relevance of the topic of the article is determined by the importance of diversification of production aimed to increase the competitiveness of agro-industrial complex at the present stage of economic development. The goal is to analyze the features of transformation of organizational and production structure of agricultural enterprise, which consists in supplementing it with new types of products, technologies, suppliers, etc. Objectives to show the importance of diversification processes to ensure sustainability of agricultural producers to negative changes in the external and internal environment. Results – it is noted that the priority areas of diversification in agro-industrial production include the organization of new branches of crop and livestock production, the inclusion of productive species, varieties or hybrids of crops in crop rotations, the development of processing sectors, the system of material and technical supply and marketing of products, etc. commodity diversity, reorientation of sales markets in agro-industrial complex is especially important in view of high risks of doing business associated with the high dependence of its results on weather conditions of the year, soil and natural-climatic factors, etc. The conducted analysis shows that the important conditions for deepening structural restructuring include developed agricultural policy of the State, a system of effective measures for regulating and supporting the industry, attracting investment in the development of agricultural sector and financial markets. The performed studies allowed us to draw the following main conclusions – diversification of production is a promising direction for the development of economic activity of enterprises, ensuring the growth of their proceeds from product sales, profits and profitability.


2018 ◽  
Vol 5 (13) ◽  
pp. 157 ◽  
Author(s):  
Javier Jiménez Pérez ◽  
José Israel Israel Yerena Yamallel ◽  
Eduardo Alanís Rodríguez ◽  
Oscar Alberto Aguirre Calderón ◽  
René Alejandro Martínez Barrón

In 1997, a restoration of Pinus culminicola was established under three exclusion areas: E1 = cattle plus small mammal exclusion, E2 = cattle exclusion and E3 = no exclusion (free range), in the Cerro El Potosi Protected Natural Area, located in Nuevo León, Mexico. The objective of this study was to determine the survival rate and the increase in diameter and height of Pinus culminicola individuals at three and 17 years after planting. The results show differences between 2000 and 2014 in survival rate and diameter and height growth in the three exclusion areas; E1 and E2 recorded higher averages. The main causes of mortality in this species are attributed to extreme weather conditions and the damage caused by cattle and small mammals.


2021 ◽  
Vol 154 (3) ◽  
pp. 321-331
Author(s):  
Sergey Goroshkevich ◽  
Svetlana Velisevich ◽  
Aleksandr Popov ◽  
Oleg Khutornoy ◽  
Galina Vasilyeva

Background and aims – Siberian stone pine is a keystone species for Siberia, and numerous studies have analyzed Siberian stone pine seeding dynamics in connection with the dynamics of weather conditions. However, all studies were based on observations before 1990. The aim of the study was to expand our knowledge about the balance of weather and climatic factors in the regulation of cone production to enable conclusions about the current reproductive function in Siberian stone pine.Material and methods – We monitored Siberian stone pine cone production in the southeastern region of the Western Siberian Plain, in association with climatic factors, over a period of 30 years. To analyze the relationship with weather conditions, we used the trait mature cone number per tree and weather data obtained from the weather station in Tomsk.Key results – During this period, cone production decreased by about one-third, mainly caused by the complete absence of high yields. The main factor negatively affecting cone production was late spring frost: severe frost occurring with a large accumulated sum of effective temperatures resulted in full cone loss, and light frost substantially reduced cone number. A less important but significant climatic factor was September temperature: as the temperature increased, the cone number decreased in the following year. Over the last 30 years, the sum of the effective temperatures at which the last spring frost occurs, as well as the average September temperature, increased considerably, resulting in reduced cone production.Conclusion – If the current climatic trend is maintained, and especially if it is strengthened, Siberian stone pine cone production in the southern boreal forest zone on the Western Siberian Plane is unlikely to provide for the effective renewal of the species.


Author(s):  
Pavel Bednář ◽  
Jakub Černý

This paper analyses the development of beech plantations aged 7 to 18 years that were planted in gap cuts (0.1–0.25 ha; ISF 50%), clear cuts (0.5–1.0 ha; ISF 87%) and finally underplanted areas in shelterwood cuts in mature spruce stands (G = 22–26 m2/ha; ISF 28%). The research consisted of the following analyses: height growth, diameter growth and beech quality development. We used standard statistical tools (p < 0.05) for evaluating height and diameter growth, which showed significant differences in both characteristics (total height and DBH) within 7-year-old and 13-year-old plantations grown in all three regeneration treatments. The tallest beech trees with greatest DBH at the age of 7 and 13 were found in clearings whereas shortest and thinnest trees grew in shelterwoods. However, at the age of 18, there was no significant different between gap cut and clear cut in both parameters. The best quality was observed in shelterwoods.


2018 ◽  
Vol 84 (9) ◽  
Author(s):  
Wen Chen ◽  
Sarah Hambleton ◽  
Keith A. Seifert ◽  
Odile Carisse ◽  
Moussa S. Diarra ◽  
...  

ABSTRACTSpore samplers are widely used in pathogen surveillance but not so much for monitoring the composition of aeromycobiota. In Canada, a nationwide spore-sampling network (AeroNet) was established as a pilot project to assess fungal community composition in air and rain samples collected using three different spore samplers in the summers of 2010 and 2011. Metabarcodes of the internal transcribed spacer (ITS) were exhaustively characterized for three of the network sites, in British Columbia (BC), Québec (QC), and Prince Edward Island (PEI), to compare performance of the samplers. Sampler type accounted for ca. 20% of the total explainable variance in aeromycobiota compositional heterogeneity, with air samplers recovering more Ascomycota and rain samplers recovering more Basidiomycota. Spore samplers showed different abilities to collect 27 fungal genera that are plant pathogens. For instance,Cladosporiumspp.,Drechsleraspp., andEntylomaspp. were collected mainly by air samplers, whileFusariumspp.,Microdochiumspp., andUstilagospp. were recovered more frequently with rain samplers. The diversity and abundance of some fungi were significantly affected by sampling location and time (e.g.,AlternariaandBipolaris) and weather conditions (e.g.,MycocentrosporaandLeptosphaeria), and depended on using ITS1 or ITS2 as the barcoding region (e.g.,EpicoccumandBotrytis). The observation that Canada's aeromycobiota diversity correlates with cooler, wetter conditions and northward wind requires support from more long-term data sets. Our vision of the AeroNet network, combined with high-throughput sequencing (HTS) and well-designed sampling strategies, may contribute significantly to a national biovigilance network for protecting plants of agricultural and economic importance in Canada.IMPORTANCEThe current study compared the performance of spore samplers for collecting broad-spectrum air- and rain-borne fungal pathogens using a metabarcoding approach. The results provided a thorough characterization of the aeromycobiota in the coastal regions of Canada in relation to the influence of climatic factors. This study lays the methodological basis to eventually develop knowledge-based guidance on pest surveillance by assisting in the selection of appropriate spore samplers.


1987 ◽  
Vol 19 (12) ◽  
pp. 123-130 ◽  
Author(s):  
M. C. R. Santos ◽  
J. F. S. Oliveira

Nitrogen transformations that can occur in WSP depend on pond and waste characteristics and are also influenced by climatic factors, like temperature and precipitation. Experiments described have been carried out using a system of three ponds in series: anaerobic, facultative and maturation, treating domestic sewage. In this paper we aim to identify the processes that might contribute to N transformations in each pond and the seasonal variations in the removal of nitrogen and its bioconversion throughout the year. Results have proved that there was an important organic N removal in the anaerobic pond, mainly due to mineralisation and not exclusively by sedimentation. Some of the processes of N transformation observed in the ponds were more strongly influenced by weather conditions than others. In some cases, the increase of biological activity that was induced by the increase in air temperature, was masked by reduced precipitation which produced less diluted treated effluents. These climatic factors can explain some of the variations observed along the year, in what concerns nitrogen compounds concentrations.


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