scholarly journals Effects of pretreatment, sowing time, sowing environment and climate factors on germination in Acer pseudoplatanus L.

2021 ◽  
Vol 145 (11-12) ◽  
pp. 557-566
Author(s):  
Zafer Yücesan ◽  
Derya Bayram

In this study, the effects of different sowing environment (greenhouse and nursery), pretreatment (cold moist stratification), different sowing time (autumn, spring and summer) and some climate factors (air temperature, relative air humidity, soil temperature and soil moisture) on the germination of Acer pseudoplatanus L. seeds were studied. Seeds were harvested from the tree located in the Karadeniz Technical University campus. Three different germination trials were carried out; (1) direct sowing in autumn after seed collection (Control), (2) sowing stratified seeds in spring (Stratification-1) and (3) sowing stratified seeds in summer (Stratification-2). During the germination trial processes, air temperature, relative air humidity, soil temperature and soil moisture were measured periodicaly. Thus, the germination percentage changes in different sowing environments have been established on the basis of some climate factors. Higher germination percentages were obtained in the autumn (Control) compared to the spring (Stratification-1) and summer (Stratification-2) sowings. The highest percentages of germination were ­determined in the control trials (70% in greenhouse and 58% in nursery). Obtained germination results based on different sowing times revealed secondary dormancy in Acer pseudoplatanus L. seeds. It has been determined that the mean germination time in the greenhouse (12 days) was shorter than the mean germination time in the nursery (18 days). In addition, the obtained results showed that stratification and sowing time have a positive effect on the mean germination time in the greenhouse. Because of getting the best germination rates, keeping some climate ­factors constant (21.0-24.9 °C air temperature; 17.0-19.9 °C soil temperature; 63.0-68.9% relative air humidity; 60.0-67.9% soil moisture) during the vegetative propagation practices in the greenhouse, should affect mass ­seedling production in Acer pseudoplatanus L.

2019 ◽  
Vol 2 (1) ◽  
pp. 1-12
Author(s):  
Merti Triyanti ◽  
Destien Atmi Arisandy

The purpose of this study was to determine the diversity of stratum vegetation in Sulap City, Lubuklinggau City based on composition, density of vegetation types and to know abiotic factors for stratum vegetation in Sulap Hill, Lubuklinggau City. This type of research is quantitative descriptive. The method used is the distance method (Centered Quarter Point). The population in this study were all species of stratum vegetation in the Bukit Sulap vegetation in Lubuklinggau City. The analysis used is in the form of density, frequency, dominance, important value index, and diversity index. The results of the study, obtained data in the study area A found 16 species of pole strata. In the study area B, 14 species of stratum were obtained, whereas in the study area C, 24 species of stratum were found. Measured abiotic factors are the air temperature in the Sulap Hill of Lubuklinggau City ranging from 28.30C - 300C with air humidity of 86% - 93%. Soil moisture ranges from 8-17 while the acidity (pH) of the soil ranges from 6.3 to 6.7. Conclusion, the mean of the Important Value Index (INP) in the Pole strata in the areas of study A, B, and C respectively is ketapang, starfruit, and coffee. Keywords: analysis, vegetation, pole strata, magic hill


Author(s):  
С. Н. Лебедев

Наводяться дані про залежність розвитку шкід-ливих поколінь ґронової листовійки на винограднихнасадженнях рівнинно-степового Криму від абіо-тичних чинників: середньодобової температуриповітря, суми опадів, відносної вологості повітря,а також площі листової поверхні куща винограду.На основі цих даних розроблені математичні мо-делі прогнозу розвитку фітофага, що дадуть змо-гу оптимізувати кратність і своєчасність захис-них заходів у боротьбі з зазначеним шкідником наконкретному сорті винограду. Provides information on the intent of the development ofmalicious generations Lobesia botrana of the leaf rolleron vine plantations of plain-steppe Crimea from abioticfactors: the average daily air temperature, amount of precipitation,relative air humidity, as well as the area of leafsurface bush of grapes. On the basis of these datadeveloped mathematical models of forecasting of thedevelopment of the phytophage, that allows to optimizethe frequency and timeliness of protective measures inthe fight against this pest on a particular cultivar ofgrapes.


1969 ◽  
Vol 93 (3-4) ◽  
pp. 149-171
Author(s):  
Jorge L. Lugo-Camacho ◽  
Miguel A. Muñoz ◽  
Juan Pérez-Bolívar ◽  
Gregory R. Brannon

Soil temperature measurements from a climate monitoring network in Puerto Rico were evaluated and the difference between mean summer and mean winter soil temperature, known as isotivity value, was calculated. Air and soil temperature was collected from five weather stations of the USDA-Natural Resources Conservation Service from sea level to 1,019 m above sea level and from different soil moisture regimes. Isotivity values ranged from 1.2 to 3.9° C with an average of 2.6° C. The 750-m elevation was identified as the limit between the isohyperthermic and isothermic soil temperature regimes in the perudic soil moisture regime in Puerto Rico. The greatest differences between mean annual soil temperature and mean annual air temperature were observed at Guánica, Combate and Guilarte (2.1 ° C) stations. The smallest differences were observed at Maricao (0.8° C) and Isabela (1.8° C) stations. The study also indicated that the mean annual soil temperature in Puerto Rico can be estimated by adding 1.8° C to the mean annual air temperature or by the equation y = -0.007x + 28.0° C. The equation indicates that 97 percent of the time the behavior of the mean annual soil temperature is a function of elevation. According to the updated soil temperature regime boundaries, eight soil series were established in the Soil Survey of San Germán Area. In an area under the isothermic soil temperature regime, four soil series were classified as Oxisols (Haploperox), two soil series as Inceptisols (Eutrudepts) and two soil series as Mollisols (Argiudolls). This is the first field recognition of the Haploperox soil great group in the United States and its territories.


Author(s):  
Amélia C. Faustino ◽  
Silvia H. N. Turco ◽  
René G. C. Silva Junior ◽  
Isadora B. Miranda ◽  
Italo E. Anjos ◽  
...  

ABSTRACT Free-range broiler producers are concerned with the thermal environment and lighting of their facilities and seek to improve these factors for the increased welfare of their broilers. The objective of this study was to evaluate the spatialization of illuminance and enthalpy in two free-range broiler sheds, one of masonry with a clay tile roof and the other built of wood with a straw roof. The data on air temperature, relative air humidity, and illuminance were recorded between September and October 2018 for five non-consecutive weeks in two periods during the day: morning (9 hours) and afternoon (15 hours). The data were collected at 42 points per shed, spaced 0.40 × 0.75 m. The experimental design was completely randomized in a 2 × 2 factorial scheme, considering two periods and two sheds. Spatial dependence was evaluated using geostatistics and interpolation maps by kriging. The facilities presented strong or moderate spatial dependence for all observed variables and periods. The small edges and lack of management of curtains resulted in the masonry shed having higher illuminance values during both periods. Although it did not present ideal values for a comfortable environment, the wood shed was more thermally efficient.


Author(s):  
Renáta Toušová ◽  
Jaromír Ducháček ◽  
Luděk Stádník ◽  
Martin Ptáček ◽  
Sylvana Pokorná

The aim of this study was to evaluate influence of climatic conditions represented by daily air temperature and relative air humidity on indicators of Holstein cows’ milk quality and production. The first dataset represented individual milk production in day of milk performance recording (milk kg, fat %, protein %, and somatic cells count thous.*ml−1). The second dataset represented total daily milk characteristics of herd (milk kg, fat %, protein % and somatic cells count thous.*ml−1). A total of 654 Holstein cows were observed and evaluated. Both datasets were evaluated in relation to selected external influences (year, month, average daily air temperature, and average daily relatively air humidity). Statistical analysis was performed using SAS 9.3, and UNIVARIATE, REG and GLM procedure. Three groups of daily air temeperature (< 4.4 °C; 4.4 – 13.2 °C; > 13.2 °C), and daily relative air humidity (< 65.3 %; 65.3 – 80.4 %; > 80.4 %) were conducted for evaluation. Significant (P < 0.05) linear regressions were computed among daily air temperature and all milk production indicators, except of somatic cells count attribute. The highest individual daily milk production (35.94 kg, P < 0.01), and protein content (3.41 %, P < 0.01) were achieved with the highest average daily air temperature. Opposite results were observed for milk yield of herd as well as protein content. Average daily relative air humidity had lower influence on individual and bulk milk samples. The better results were achieved for both datasets (individual and bulk samples) in groups (65.3 – 80.4 %; > 80.4 %) of average daily relative air humidity. Obtained results point out importance of outdoor climatic parameters monitoring and preventive measures of climatic conditions in the stable.


Author(s):  
Bronius Kavolėlis ◽  
Rolandas Bleizgys

The objective of the work is to substantiate the optimum values of temperature‐humidity regime in cowsheds which are required in designing and exploiting a ventilation system. An equation, which connects relative air humidity of a room with difference between inside and outside air temperature, was developed. Another equation, which shows the greatest allowed difference of temperatures under which water vapour does not condensate on the internal surface of an external partition, was composed as well. By analytical and experimental investigation, it is substantiated that possible minimum relative air humidity in a cowshed is by about 5 % lower than relative outside air humidity. Optimal difference between inside and outside air temperature in the cold period of the year is about 4 °C.


2018 ◽  
Vol 78 (4) ◽  
pp. 736-741 ◽  
Author(s):  
L. E. N. Costa ◽  
R. P. Farias ◽  
A. C. P. Santiago ◽  
I. A. A. Silva ◽  
I. C. L. Barros

Abstract We analyzed floristic variations in fern’s metacommunity at the local scale and their relationship with abiotic factors in an Atlantic Forest remnant of northeastern Brazil. Floristic and environmental variations were accessed on ten plots of 10 × 20 m. We performed cluster analyses, based on Bray-Curtis dissimilarity index to establish the floristic relationship. The influence of abiotic factors: luminosity, temperature, relative air humidity and relative soil moisture was evaluated from a redundancy analysis. We found 24 species belonging to 20 genera and 12 families. The fern’s flora showed high floristic heterogeneity (>75% for most of the plot’s associations). The fern’s metacommunity was structured along an abiotic gradient modulated by temperature, luminosity, and relative soil moisture.


2021 ◽  
Vol 25 (2) ◽  
pp. 60-65
Author(s):  
S.A. Kurolap ◽  
V.S. Petrosyan ◽  
O.V. Klepikov ◽  
V.V. Kulnev ◽  
D.Yu. Martynov

Based on the analysis of official statistics from the Voronezh Hydrometeorological Service, the patterns of the dynamics of pollutants (formaldehyde and soot) are investigated depending on the combination of various meteorological parameters — air temperature, wind speed, relative air humidity. A positive relationship has been established between the increase in atmospheric pollution with formaldehyde and air temperature. With increasing wind speed and relative humidity, the concentration of formaldehyde and soot in the atmosphere of the city, as a rule, decrease. The maximum permissible level of carcinogenic risk to public health has been established, causing concern. The obtained patterns can be used to predict the level of technogenic pollution of the city’s atmosphere, depending on meteorological conditions.


1977 ◽  
Vol 88 (2) ◽  
pp. 405-410 ◽  
Author(s):  
J. Norrington-Davies ◽  
J. H. Harries

SUMMARYTwo varieties of Lolium perenne, the diploid Hora and the tetraploid Terhoy were sown either as a pure stand or as a binary mixture on to the surface of multipots filled with a standard John Innes compost. Density of sowing was varied over the range of 16, 24, 36, 50 and 100 seeds/pot. There were four replicates. The pattern of germination was followed over a period of 14 days when it was found that (i) the varieties did not differ in their germination when grown alone, but in mixtures the diploid was slower to germinate than the tetraploid, (ii) as the density of sowing per pot was increased, the mean germination time (MGT) was increased, and (iii) the final germination of both verities decreased with increasing density.In a second experiment the same procedures were followed as before but seed of each variety was sown either as a pure stand or in a mixture of varying proportion as follows: 100:0, 75:25, 50:50, 25:75, 0:100.The results showed that (i) the diploid had the fastest MGT whilst the mixture values showed no significant variation, and (ii) the final germination percentage of the diploid decreased relative to its pure stand value as its proportion in mixtures decreased, whilst the tetraploid under the same circumstances increased relative to its pure stand value.It is suggested that differences such as those found could be explained by the presence of germination inhibitors in the seed coats of the two ryegrass varieties.


2018 ◽  
Vol 2018 ◽  
pp. 1-8
Author(s):  
Stephanie Stiegel ◽  
Jasmin Mantilla-Contreras

Morphological and functional leaf traits like leaf toughness and nutrient content are essentially influenced by the environment, especially through light and climatic conditions. Varying light conditions have been identified as a significant predictor for the variation of many leaf traits. However, the leaf acclimation to light is suggested to be of secondary importance. The aim of the experimental study was to analyse environmental effects (microclimate and soil moisture), which are present in upper canopies of forest stands, on leaf traits of juvenileFagus sylvaticaL. (European beech; Fagaceae),Acer pseudoplatanusL. (sycamore maple; Sapindaceae), andCarpinus betulusL. (hornbeam; Betulaceae). The experimental design managed to imitate two distinct microclimates causing different temperature and air humidity conditions. Furthermore, the irrigation treatment with different levels of applied water caused distinct soil moisture conditions in the trial pots. As a result of the treatments, leaves ofC. betulusshowed a tendency of decreased specific leaf area (SLA) caused by the treatment with warmer and drier microclimate. The environmental effect on SLA was even stronger with lower soil moisture conditions. Chlorophyll content showed lower values in treatments with higher soil moisture conditions in both greenhouses forF. sylvaticaandA. pseudoplatanus. The trends are in accordance with combined effects of temperature, air humidity, and soil moisture on SLA, and increased leaf chlorophyll content caused by slight drought stress. Plants in the greenhouses were exposed to full sunlight indicating a microclimatic environment comparable to upper canopies in forest stands. The comparable SLA and chlorophyll content between leaves of matureF. sylvaticatrees in upper canopies and juvenile trees of the greenhouses suggest similar environmental conditions instead of ontogenetic effects that are responsible for the formation of leaf trait characteristics.


Sign in / Sign up

Export Citation Format

Share Document