scholarly journals Variations in the length of Scots pine (Pinus sylvestris L.) needles under the influence of climatic factors and solar activity in different conditions of northern taiga

2019 ◽  
Vol 65 (No. 8) ◽  
pp. 313-320
Author(s):  
Olga Tyukavina ◽  
Nikolay Neverov ◽  
Alexander Mineev

The aim of the study was to assess the influence of climatic factors on the growth of pine needles in different conditions of the water regime of soil. Studies were conducted in lichen pine forests, cowberry pine forests, blueberry pine forests, shrub-sphagnum pine forest and pine on swamp in the Arkhangelsk forestry regions (northern taiga). The needle length is influenced by solar activity (the Wolf number). The effect of solar activity on increasing the needle length is greatest in optimal growing conditions. In northern taiga conditions, air temperature is the main climatic factor affecting the growth of needles. In the blueberry, cowberry and lichen pine forests, an inverse high correlation of the needle length with the night air temperature of August of the current year was revealed. The pine on swamp revealed a high correlation between the needle length and the air temperature at the end of July of the current year of needle development. In the year preceding the needle development, a high inverse correlation was found between the needle length and the temperature of mid-September in the cowberry and blueberry pine forests. In the current year, high correlations of the lengths of needles and precipitation were observed in extreme growing conditions.<br /> 

2019 ◽  
Vol 65 (No. 1) ◽  
pp. 33-39
Author(s):  
Olga N. Tyukavina ◽  
Nikolay A. Neverov ◽  
Denis N. Klevtsov

The aim of the study was to determine the adaptive characteristics of pine needles associated with age and different growing conditions. The length of the needles decreases and its variability reduces with increasing dryness and poverty of the soil. In oppressed trees, the coefficient of variability of the length of the needles on the tree is 8%. The coefficient of variation in the length of needles approaching 20% will indicate the best conditions for the growth of a particular tree. Trends of the dependence of width and thickness of needles on growing conditions were not identified. The area of needles in pine forests with optimal water regime of soils (blueberry, cowberry type) varies in the range of 112–124 mm<sup>2</sup>. In extreme growing conditions pine needles area is reduced by 27–33% and equals 76–86 mm<sup>2</sup>. These ranges of values of the areas of needles are typical for plantings of the third and fourth classes of age. Changing the width and thickness of the needles is aimed at compensating for changes in the length of the needles in the direction of maintaining the optimal area for these conditions needles. In extreme conditions, the area of the assimilating tissue increases, and the area of the conducting tissue (stele) decreases. Correlation dependences of the area of the stele of needles with the cross-sectional area, with the area of conducting beams, with the number of resin canals and with the cover fabric are revealed.


2006 ◽  
Vol 12 (1) ◽  
pp. 43-53 ◽  
Author(s):  
Jerzy Boryczka ◽  
Maria Stopa-Boryczka

Abstract The objective of the work is to determine the periodicity and trends of change in air temperature and precipitation in Poland in the time period of the 18th-20th centuries, together with the forecast for the 21st century. There are interesting diagrams of the temporal changes of solar activity and North Atlantic Oscillation (NAO) indicator, with the forecast reaching the year 2100. The forecasts were obtained on the basis of interpretations of the Wolf number and NAO indicator cycles, determined with the method of “regression sinusoids”. The fluctuations of the air temperature and precipitations during winter in Warsaw and in Cracow are closely correlated.


Author(s):  
Olena P. Mitryasova ◽  
Anna S. Pryhodko

The purpose of research consists in definition and an estimation of climatic factors influence on disease incidence of Covid-19 on an example of Mykolaiv city. In research we used such scientific methods: theoretical methods: analysis, synthesis, monitoring, systematization, generalization. For research facility, were held by calculations based on software Microsoft Excel. The calculations were performed using the formula correlation. Results. The study examines the influence of climatic factors such as air temperature, humidity, solar radiation activity, wind speed, rainfall, and length of daylight. For the pair «Disease incidence – Temperature» the correlation coefficient is −0.74. For the pair «Disease incidence − Solar Radiation» correlation coefficient is −0.71. For the pair «Disease incidence – Daylight hours» correlation coefficient is −0.70. Humidity, as a derivative of air temperature, is evidenced by a comparison of decline periods and growth of these values. In the spring, along with the increase in temperature, the humidity dropped, and in the fall, when the air temperature dropped, the humidity increased. This factor also affected the spread of the virus in the second half of the year, when the humidity increased the virus began to spread faster. For the pair «Disease incidence – Humidity» correlation coefficient is +0.73 (average direct correlation). Other climatic factors, such as wind speed and rainfall, have not been shown to have a significant effect on the rate of disease spread. For the pair «Disease incidence − Wind speed» correlation coefficient is +0.32, which corresponds to a weak direct correlation. For the pair «Disease incidence − Rainfall» correlation coefficient is −0.30, which indicates a weak inverse correlation. Conclusion. The results of the study show that the reduction of disease incidence is observed at high temperatures, high activity of solar radiation, and prolonged daylight, which determines the conditions for the prevention of such diseases and will improve the quality of life to achieve sustainable development.


2002 ◽  
Vol 82 (3) ◽  
pp. 499-506 ◽  
Author(s):  
Zakaria M Sawan ◽  
Louis I Hanna ◽  
Willis L McCuistion

The cotton plant (Gossypium spp.) is sensitive to numerous environmental factors. This study was aimed at predicting effects of climatic factors grouped into convenient intervals (in days) on cotton flower and boll production compared with daily observations. Two uniformity field trials using the cotton (G. barbadense L.) cv. Giza 75 were conducted in 1992 and 1993 at the Agricultural Research Center, Giza, Egypt. Randomly chosen plants were used to record daily numbers of flowers and bolls during the reproductive stage (60 days). During this period, daily air temperature, temperature magnitude, evaporation, surface soil temperature, sunshine duration, humidity, and wind speed were recorded. Data, grouped into intervals of 2, 3, 4, 5, 6, and 10 d, were correlated with cotton production variables using regression analysis. Evaporation was found to be the most important climatic variable affecting flower and boll production, followed by humidity and sunshine duration. The least important variables were surface soil temperature at 0600 and minimum air temperature. The 5-d interval was found to provide the best correlation with yield parameters. Applying appropriate cultural practices that minimize the deleterious effects of evaporation and humidity could lead to an important improvement in cotton yield in Egypt. Key words: Cotton, flower production, boll production, boll retention


2016 ◽  
Vol 20 (7) ◽  
pp. 2573-2587 ◽  
Author(s):  
Zhongwei Huang ◽  
Hanbo Yang ◽  
Dawen Yang

Abstract. With global climate changes intensifying, the hydrological response to climate changes has attracted more attention. It is beneficial not only for hydrology and ecology but also for water resource planning and management to understand the impact of climate change on runoff. In addition, there are large spatial variations in climate type and geographic characteristics across China. To gain a better understanding of the spatial variation of the response of runoff to changes in climatic factors and to detect the dominant climatic factors driving changes in annual runoff, we chose the climate elasticity method proposed by Yang and Yang (2011). It is shown that, in most catchments of China, increasing air temperature and relative humidity have negative impacts on runoff, while declining net radiation and wind speed have positive impacts on runoff, which slow the overall decline in runoff. The dominant climatic factors driving annual runoff are precipitation in most parts of China, net radiation mainly in some catchments of southern China, air temperature and wind speed mainly in some catchments in northern China.


2015 ◽  
Vol 29 (2) ◽  
pp. 129-135 ◽  
Author(s):  
Alina Danielewska ◽  
Marek Urbaniak ◽  
Janusz Olejnik

Abstract The Scots pine is one of the most important species in European and Asian forests. Due to a widespread occurrence of pine forests, their significance in the energy and mass exchange between the Earth surface and the atmosphere is also important, particularly in the context of climate change and greenhouse gases balance. The aim of this work is to present the relationship between the average annual net ecosystem productivity and growing season length, latitude and air temperature (tay) over Europe. Therefore, CO2 flux measurement data from eight European pine dominated forests were used. The observations suggest that there is a correlation between the intensity of CO2 uptake or emission by a forest stand and the above mentioned parameters. Based on the obtained results, all of the selected pine forest stands were CO2 sinks, except a site in northern Finland. The carbon dioxide uptake increased proportionally with the increase of growing season length (9.212 g C m-2 y-1 per day of growing season, R2 = 0.53, p = 0.0399). This dependency showed stronger correlation and higher statistical significance than both relationships between annual net ecosystem productivity and air temperature (R2 = 0.39, p = 0.096) and annual net ecosystem productivity and latitude (R2 = 0.47, p = 0.058). The CO2 emission surpassed assimilation in winter, early spring and late autumn. Moreover, the appearance of late, cold spring and early winter, reduced annual net ecosystem productivity. Therefore, the growing season length can be considered as one of the main factor affecting the annual carbon budget of pine forests.


Author(s):  
Xuelei Zhang ◽  
Weihua Xiao ◽  
Yicheng Wang ◽  
Yan Wang ◽  
Miaoye Kang ◽  
...  

Abstract This paper focuses on determining the spatial and temporal characteristics of the sensitivity coefficients (SCs) between potential evapotranspiration (ET0) and key climatic factors across the Shiyang River Basin (SYRB) from 1981 to 2015. Penman–Monteith equation and a sensitivity analysis were used to calculate ET0 and the SCs for key climatic factors. Sen's slope was used to analyze the observed series. According to the results, the sensitivity significances were in the order of relative humidity (RH) &gt; net solar radiation (NSR) &gt; wind speed (WS) &gt; maximum air temperature (Tmax) &gt; minimum air temperature (Tmin). The SCs for the RH and NSR were larger in the upper mountainous region, while the other three coefficients were larger in the middle and lower reaches. All five climatic factors for the ET0 SCs showed increasing trends in the mountainous region, and the Tmax, WS and RH SCs increased in the middle and lower reaches. Over the past 35 years, the change in ET0 was dominated by the air temperature (T), RH and NSR, and the increase in ET0 during the studied period was mainly due to the increases in T and NSR.


Water ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 877 ◽  
Author(s):  
Monika Okoniewska ◽  
Danuta Szumińska

The paper analyses changes in potential evaporation E0 (mm) in north-western Poland in the years 1952–2018. E0 (mm) has been calculated according to Ivanov’s formula based on the monthly values of air temperature (t, °C) and relative air humidity (f, %) for six weather stations of the Institute of Meteorology and Water Management. The data were collected using the Statistica software ver. 13 and the QGIS software ver. 3.80. The results indicate statistically significant trends in the increase of E0 during the period 1952–2018, and that it is particularly high during the spring and summer months, which should be associated with a statistically significant increase in air temperature and a decrease in relative humidity at all examined stations. The results also indicate an exceptionally high increase in evaporation since the end of the 20th century and in the 21st century, which reflects a potentially higher risk of permanent changes in hydrological conditions. The research results point to the major role of climatic factors in the often-dramatic decreases in water resources observed in the 21st century, particularly in lakes and small watercourses. The progressing reduction of water resources may cause permanent changes in physical and chemical conditions in waterbodies.


2020 ◽  
Vol 2020 ◽  
pp. 1-23
Author(s):  
Ziyang Zhao ◽  
Hongrui Wang ◽  
Cheng Wang ◽  
Wangcheng Li ◽  
Hao Chen ◽  
...  

The impact of global climate change on agroecosystems is growing, affecting reference crop evapotranspiration (ET0) and subsequent agricultural water management. In this study, the climate factors temporal trends, the spatiotemporal variation, and the climate driving factors of ET0 at different time scales were evaluated across the Northern Yellow River Irrigation Area (NYR), Central Arid Zone (CAZ), and Southern Mountain Area (SMA) of Ningxia based on 20 climatic stations’ daily data from 1957 to 2018. The results showed that the Tmean (daily mean air temperature), Tmax (daily maximum air temperature), and Tmin (daily minimum air temperature) all had increased significantly over the past 62 years, whilst RH (relative humidity), U2 (wind speed at 2 m height), and SD (sunshine duration) had significantly decreasing trends across all climatic zones. At monthly scale, the ET0 was mainly concentrated from April to September. And at annual and seasonal scales, the overall increasing trends were more pronounced in NX, NYR, and SMA, while CAZ was the opposite. For the spatial distribution, ET0 presented a trend of rising first and then falling at all time scales. The abrupt change point for climatic factors and ET0 series was obtained at approximately 1990 across all climatic zones, and the ET0 had a long period of 25a and a short period of 10a at annual scale, while it was 15a and 5a at seasonal scale. RH and Tmax were the most sensitive climatic factors at the annual and seasonal scales, while the largest contribution rates were Tmax and SD. This study not only is important for the understanding of ET0 changes but also provides the preliminary and elementary reference for agriculture water management in Ningxia.


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