scholarly journals Врожайність пшениці озимої залежно від погодних умов у ранньовесняний період в умовах північного Степу України

2018 ◽  
pp. 62-69
Author(s):  
М. І. Мостіпан ◽  
Н. Л. Умрихін
Keyword(s):  
Winter Wheat ◽  
Air Temperature ◽  
Early Spring ◽  
Daily Temperature ◽  
Steady Increase ◽  
Average Daily Temperature ◽  
The Third ◽  
Average Productivity ◽  
Early Beginning ◽  
Mixed Age

Тривалими польовими дослідженнями доведено, що в північному Степу України чим пізніше відновлюється весняна веґетація озимої пшениці, тим меншою є врожайність. При цьому час відновлення веґетації має значний вплив на врожайність різновікових посівів. У разі надраннього відновлення веґетації (III декада лютого) врожайність  посівів з сівбою у період з кінця серпня до початку жовтня є майже однаковою і становить від 6,44 до 6,96 т/га. У випадку пізнього відновлення веґетації (початок квітня) найбільш високу врожайність формують посіви з сівбою з 10 по 25 вересня. Їх врожайність у середньому за роки досліджень становила 3,86–3,91 т/га. Чим коротшим є період від переходу температури через 0 0С до +5 0С, тим більшою є врожайність озимої пшениці. У середньому за роки досліджень врожайність озимої пшениці за тривалості періоду від переходу температури через 0 0С до +5 0С до 10 днів становила 6,04 т/га, а в разі подовження цього періоду до 30 і більше днів зменшувалася до 3,76 т/га. It has been established that in the Northern Steppe of Ukraine the beginning of spring vegetation of winter wheat starts at different periods of time. The earliest vegetation (February 22) was observed in 1990, and the latest vegetation (April 4) was in 2003. Therefore, it has been suggested to distinguish the very early (the third decade of February) beginning of vegetation, early beginning of vegetation (the first–second decade of March), middle-time vegetation (the third decade of March) and late beginning of vegetation (the first decade of April) of winter wheat. During the whole period of observations from 1986 to 2005, the  very early beginning of vegetation was observed during 3 years (15%), early vegetation – 4 years (20%), middle-time vegetation – 8 years (40%), and late vegetation – 5 years (25%). The analysis of winter wheat productivity shows that the later is the beginning of spring vegetation, the less productivity of winter wheat. During the very early spring vegetation in the third decade of February,  productivity is twice as large as compared with the late vegetation in the first decade of April. On average, over the years of the study, these indicators were 6.74 and 3.28 t/ha respectively. In the very early vegetation (the 3rd decade of February), productivity of the mixed-age crops is almost the same and ranges from 6.44 to 6.96 t/ha. During the late vegetation (early April), the highest productivity is formed by the crops sown from the 10th to the 25th of September. Their average productivity during the years of the study was 3.86–3.91 t/ha. With this period of spring vegetation, the productivity of crops sown on September 2nd and October 2nd is almost the same and is 2.99 and 2.88 t/ha respectively, but significantly higher than the productivity of crops sown on August 25th. For the formation of winter wheat harvest, the change of the average daily temperature above 0 °C is important, as well as the duration of the period from that time to the beginning of spring vegetation. That is the steady increase in average daily air temperature to more than +5 °С. The increase in the period of time from the date of the change of the average daily air temperature above 0 °C to the beginning of spring vegetation causes the decrease in the productivity of winter wheat. During the years when the duration of this period was up to 10 days, the productivity of winter wheat averaged 6.04 t/ha, and during the years with this period of more than 30 days, the productivity decreased to 3.76 t/ha. The shorter period from the change of the average daily air temperature above 0 °C to the time of the beginning of spring vegetation, the higher the dependence of the level of winter wheat productivity on the sowing terms. If this period is longer than 30 days, the highest productivity was formed by crops sown on September 17th and September 25th, and during the years when this period lasted from 10 to 20 days, higher productivity was provided by the crops sown from September 10th to September 25th. With the duration of the period from the date of the change of the average daily air temperature above 0 °C to the beginning of spring vegetation to 20 days, the productivity of winter wheat crops with early sowing on September 2nd and October 2nd is almost the same. The crops sown on September 2nd with the duration of this period up to 10 days formed productivity of 5.44 t/ha, and the crops sown on October 2nd – 5.56 t/ha. At the same time, if the duration of this period exceeds 20 days, the crops sown on October 2nd form a considerably higher productivity than the crops sown on September 2nd.

scholarly journals Вплив погодних умов веґетаційного періоду на елементи продуктивності та урожайність проса прутоподібного

2017 ◽  
pp. 50-55
Author(s):  
М. І. Кулик ◽  
І. І. Рожко
Keyword(s):  
Unit Area ◽  
Weather Conditions ◽  
Vegetation Period ◽  
Close Correlation ◽  
Daily Temperature ◽  
Average Daily Temperature ◽  
Quantitative Indices ◽  
The Third ◽  
Number Of Stems

З'ясовано вплив погодних умов веґетації на мінливість елементів продуктивності (висоти та густоти стеблостою) проса прутоподібного. Визначено вплив середньодобової температури повітря та суми опадів під час веґетації рослин на урожайність фітомаси культури в розрізі років дослідження. Наведено кореляційні залежності між кількісними показниками рослин (елементами продуктивності) третього–шостого років веґетації та урожайністю фітомаси проса прутоподібного. Встановлено, що урожайність сухої надземної веґетативної маси проса прутоподібного в більшій мірі обумовлюється кількістю стебел на одиницю площі у тісному взаємозв’язку із середньодобовою температурою повітря, в меншій мірі – висотою рослин та сумою опадів за веґетаційний період. The influence of weather conditions of vegetation on the variability of the elements of productivity (height and density of stems) of switchgrass is determined. The influence of average daily temperature of air and the amount of precipitation during vegetation of plants on the yield of phytomass of culture in terms of research years is determined. The correlation between quantitative indices of plants (elements of productivity) of the third–sixth years of vegetation and yield of phytomass of switchgrass is shown. It has been established that the yield of dry vegetative mass of switchgrass is largely determined by the number of stems per unit area in close correlation with the average daily temperature of air, to a less extent – the height of plants and the amount of precipitation during the vegetation period.

Earliness and duration of grain fill in winter wheat

1992 ◽  
Vol 72 (1) ◽  
pp. 35-48 ◽  
Author(s):  
T. L. Housley ◽  
H. W. Ohm
Keyword(s):  
Genetic Diversity ◽  
Triticum Aestivum ◽  
Winter Wheat ◽  
Triticum Aestivum L ◽  
Kernel Weight ◽  
Daily Temperature ◽  
Day Length ◽  
Effect Of Temperature ◽  
Average Daily Temperature ◽  
Influence Of Temperature On

The duration of grain fill in wheat (Triticum aestivum L.) is one of the determinants of kernel weight. The purpose of this research was to investigate the genetic diversity for duration of grain fill in winter wheat. In one experiment the genetic diversity for duration of grain fill and the influence of temperature on heading, anthesis and duration were assessed in 175 cultivars and lines of diverse plant type and origin planted at the Purdue Agronomy Research Center. The effect of temperature on the rate and duration of grain fill was further assessed in two cultivars, Fundulea and Caldwell, over 4 yr. In a second experiment Fundulea and Caldwell were grown in the field under altered day length (12, normal, 17 h) to manipulate date of anthesis. Duration of grain fill in the 175 entries averaged 28 ± 0.9 d. Heading occurred on 17 different dates, anthesis on 13 different dates and grain maturity on 17 different dates. The average daily temperature (ADT) during grain fill ranged between 21.2 and 22.5 °C. Comparisons of the ADT through grain fill for Fundulea and Caldwell over 4 yr indicated a 0.83-d reduction in duration for each degree rise in ADT. Leaf area, plant height, and tiller number were similar for cultivars exposed to 17 h, 12 h, or normal day lengths. Anthesis was 5 d earlier and the ADT during grain fill was less (20–21 °C) in plants exposed for 17 h compared to those exposed for 12 h (22 °C). Weight of 1000 kernels was significantly higher in plants with early anthesis dates, but yield was not significantly changed by the day length treatments. There appeared to be genetic differences in temperature sensitivity during reproductive development which could be exploited in selecting cultivars suitable for early anthesis. The general similarity of duration for all experiments suggests that environmental constraints imposed by latitude and selection for yield, have led to a narrow germplasm base regarding duration of grain fill.Key words: Triticum aestivum, average daily temperature during grain fill, duration of grain fill, anthesis, heading

scholarly journals The Impact of Microclimate on the Reproductive Phenology of Female Populus tomentosa in a Micro-Scale Urban Green Space in Beijing

2021 ◽  
Vol 13 (6) ◽  
pp. 3518
Author(s):  
Xiaoyi Xing ◽  
Li Dong ◽  
Cecil Konijnendijk ◽  
Peiyao Hao ◽  
Shuxin Fan ◽  
...  
Keyword(s):  
Seed Dispersal ◽  
Spatial Variation ◽  
Air Temperature ◽  
Green Space ◽  
Populus Tomentosa ◽  
Early Spring ◽  
Reproductive Phenology ◽  
Primary Role ◽  
Micro Scale ◽  
The Impact

The spatial variation of poplars’ reproductive phenology in Beijing’s urban area has aggravated the threat of poplar fluff (cotton-like flying seeds) to public health. This research explored the impact of microclimate conditions on the reproductive phenology of female Populus tomentosa in Taoranting Park, a micro-scale green space in Beijing (range <1 km). The observed phenophases covered flowering, fruiting, and seed dispersal, and ENVI-MET was applied to simulate the effect of the microclimate on SGS (start day of the growing season). The results showed that a significant spatial variation in poplar reproductive phenology existed at the research site. The variation was significantly affected by the microclimate factors DMT (daily mean temperature) and DMH (daily mean heat transfer coefficient), with air temperature playing a primary role. Specifically, the phenology of flowering and fruiting phenophases (BBB, BF, FF, FS) was negatively correlated with DMT (−0.983 ≤ r ≤ −0.908, p <0.01) and positively correlated with DMH (0.769 ≤ r ≤ 0.864, p < 0.05). In contrast, DSD (duration of seed dispersal) showed a positive correlation with DMT (r = 0.946, p < 0.01) and a negative correlation with DMH (r = −0.922, p < 0.01). Based on the findings, the increase in air convection with lower air temperature and decrease in microclimate variation in green space can be an effective way to shorten the seed-flying duration to tackle poplar fluff pollution in Beijing’s early spring.

Differences in warming impacts on wheat productivity among varieties released in different eras in North China

2015 ◽  
Vol 153 (8) ◽  
pp. 1353-1364 ◽  
Author(s):  
C. Y. ZHENG ◽  
J. CHEN ◽  
Z. W. SONG ◽  
A. X. DENG ◽  
L. N. JIANG ◽  
...  
Keyword(s):  
Winter Wheat ◽  
Grain Yield ◽  
Biomass Production ◽  
Air Temperature ◽  
North China ◽  
Growth Period ◽  
Wheat Breeding ◽  
Wheat Growth ◽  
Positive Effects ◽  
Significant Difference

SUMMARYTen leading varieties of winter wheat released during 1950–2009 in North China were tested in a free-air temperature increase (FATI) facility. The FATI facility mimicked the local air temperature pattern well, with an increase of 1·1 °C in the daily mean temperature. For all the tested varieties, warming caused a significant reduction in the total length of wheat growth period by 5 days and especially in the pre-anthesis period, where it was reduced by 9 days. However, warming increased wheat biomass production and grain yield by 8·4 and 11·4%, respectively, on an average of all the tested varieties. There was no significant difference in the warming-led reduction in the entire growth period among the tested varieties. Interestingly, the warming-led increments in biomass production and grain yield increased along with the variety release year. Significantly higher warming-led increases in post-anthesis biomass production and 1000-grain weight were found in the new varieties compared to the old ones. Meanwhile, a significant improvement in plant productivity was noted due to wheat breeding during the past six decades, while no significant difference in the length of entire growth period was found among the varieties released in different eras. The results demonstrate that historical wheat breeding might have enhanced winter wheat productivity and adaptability through exploiting the positive effects rather than mitigating the negative impacts of warming on wheat growth in North China.

Problems Of Metabolic Syndrome

2021 ◽  
Vol 03 (06) ◽  
pp. 52-55
Author(s):  
Maksuda Ahmedjanovna Karimova ◽  
◽  
Dilnoza Kakhramanovna Kurbanbaeva ◽  
Keyword(s):  
Diabetes Mellitus ◽  
Risk Factors ◽  
Metabolic Syndrome ◽  
Lifestyle Modification ◽  
Syndrome X ◽  
Steady Increase ◽  
The Third ◽  
Calorie Content ◽  
Single Term ◽  
Life Threatening

At the beginning of the third millennium, for mankind, which overcame the epidemic of life-threatening infections during its centuries-old history, the problem of cardiovascular diseases (CVD) came to the fore in relevance among all causes of morbidity and mortality. A significant role in this was played by lifestyle modification associated with limiting physical activity, increasing the calorie content of food, and a steady increase in emotional stress. All of this potentiates the main risk factors for CVD, which are a “negative asset of progress,” namely increased blood pressure (BP), dyslipidemia, diabetes mellitus (DM) and obesity. Since 1988, after G. Reaven's Banting lecture, it is customary to designate the interconnected combination of these pathologies by the single term "metabolic syndrome X".

scholarly journals Trends and abrupt changes in 104 years of ice cover and water temperature in a dimictic lake in response to air temperature, wind speed, and water clarity drivers

2016 ◽  
Vol 20 (5) ◽  
pp. 1681-1702 ◽  
Author(s):  
Madeline R. Magee ◽  
Chin H. Wu ◽  
Dale M. Robertson ◽  
Richard C. Lathrop ◽  
David P. Hamilton
Keyword(s):  
Wind Speed ◽  
Water Temperature ◽  
Air Temperature ◽  
Water Clarity ◽  
Ice Cover ◽  
Ice Thickness ◽  
Lake Mendota ◽  
The Third ◽  
Abrupt Changes ◽  
Hypolimnetic Heating

Abstract. The one-dimensional hydrodynamic ice model, DYRESM-WQ-I, was modified to simulate ice cover and thermal structure of dimictic Lake Mendota, Wisconsin, USA, over a continuous 104-year period (1911–2014). The model results were then used to examine the drivers of changes in ice cover and water temperature, focusing on the responses to shifts in air temperature, wind speed, and water clarity at multiyear timescales. Observations of the drivers include a change in the trend of warming air temperatures from 0.081 °C per decade before 1981 to 0.334 °C per decade thereafter, as well as a shift in mean wind speed from 4.44 m s−1 before 1994 to 3.74 m s−1 thereafter. Observations show that Lake Mendota has experienced significant changes in ice cover: later ice-on date(9.0 days later per century), earlier ice-off date (12.3 days per century), decreasing ice cover duration (21.3 days per century), while model simulations indicate a change in maximum ice thickness (12.7 cm decrease per century). Model simulations also show changes in the lake thermal regime of earlier stratification onset (12.3 days per century), later fall turnover (14.6 days per century), longer stratification duration (26.8 days per century), and decreasing summer hypolimnetic temperatures (−1.4 °C per century). Correlation analysis of lake variables and driving variables revealed ice cover variables, stratification onset, epilimnetic temperature, and hypolimnetic temperature were most closely correlated with air temperature, whereas freeze-over water temperature, hypolimnetic heating, and fall turnover date were more closely correlated with wind speed. Each lake variable (i.e., ice-on and ice-off dates, ice cover duration, maximum ice thickness, freeze-over water temperature, stratification onset, fall turnover date, stratification duration, epilimnion temperature, hypolimnion temperature, and hypolimnetic heating) was averaged for the three periods (1911–1980, 1981–1993, and 1994–2014) delineated by abrupt changes in air temperature and wind speed. Average summer hypolimnetic temperature and fall turnover date exhibit significant differences between the third period and the first two periods. Changes in ice cover (ice-on and ice-off dates, ice cover duration, and maximum ice thickness) exhibit an abrupt change after 1994, which was related in part to the warm El Niño winter of 1997–1998. Under-ice water temperature, freeze-over water temperature, hypolimnetic temperature, fall turnover date, and stratification duration demonstrate a significant difference in the third period (1994–2014), when air temperature was warmest and wind speeds decreased rather abruptly. The trends in ice cover and water temperature demonstrate responses to both long-term and abrupt changes in meteorological conditions that can be complemented with numerical modeling to better understand how these variables will respond in a future climate.

Cytokinins and abscisic acid in hardening winter wheat

1990 ◽  
Vol 68 (7) ◽  
pp. 1597-1601 ◽  
Author(s):  
John S. Taylor ◽  
Munjeet K. Bhalla ◽  
J. Mason Robertson ◽  
Lu J. Piening
Keyword(s):  
Triticum Aestivum ◽  
Abscisic Acid ◽  
Winter Wheat ◽  
Leaf Tissue ◽  
Triticum Aestivum L ◽  
Early Spring ◽  
Growth Chamber ◽  
Late Winter ◽  
Sequence Of Events ◽  
Freeze Dried

During overwintering in a northern climate, winter wheat goes through a hardening process, followed by dehardening in late winter – early spring. This sequence of events may be partially controlled by changes in endogenous hormone levels. Crowns and leaf tissue from field grown winter wheat (Triticum aestivum L. cv. Norstar) seeded at the beginning of September were collected and freeze-dried at monthly intervals during the winters of 1985–1986 and 1986–1987. Material was also sampled and freeze-dried from seedlings grown in a growth chamber under hardening conditions (21 °C for 2 weeks plus 3 °C for 6 weeks) or nonhardening conditions (3 weeks at 21 °C). The tissues were analysed for cytokinins and abscisic acid. Cytokinin levels, measured with the soybean hypocotyl section assay, declined from October onwards and then rose to a peak in late winter (January and February, winter 1986–1987; February and March, winter 1985–1986), subsequently declining again. Abscisic acid, quantitated as the methyl ester by gas chromatography with an electron capture detector, increased in level from October to December, then decreased to a relatively low level between January and March. Hardened seedlings from the growth chamber contained significantly higher abscisic acid levels and significantly lower cytokinin levels than did the nonhardened seedlings. Key words: abscisic acid, cytokinins, hardening, Triticum aestivum, winter wheat.

scholarly journals Analysis of climate of Rivnenskyi Nature Reserve from 2000 to 2015

2018 ◽  
pp. 53-60
Author(s):  
Oleksandr Horbach
Keyword(s):  
Nature Reserve ◽  
Winter Season ◽  
Summer Season ◽  
Daily Temperature ◽  
Winter Period ◽  
Autumn Period ◽  
Average Daily Temperature ◽  
Spring Period ◽  
Unstable Temperature

The analysis of monthly climatic terms of Rivnenskyi Nature Reserve was conducted. It is marked that weather terms have substantial differences due to an unstable temperature condition since creation of reserve. A spring period was the shortest in 2013 – 64 days and had the greatest average daily temperature 11.9 °С. Protracted a spring period was in 2002 – 123 days. The most of precipitations in a spring period was fixed in 2008 – 196.2 mm, and the least in 2011 – 42.1 mm. A summer period in 2015 became the most protracted – 131 day. Moreover, the least protracted summer was in 2006 – 90 days. The warmest summer season was in 2010 with an average daily temperature 19.8 °С. The most raining summer was in 2007 when a 471.3 mm of precipitations is fixed, and the least raining summer was in 2002 (144.6 mm of precipitations). The most protracted autumn period was in 2006 – 107 days and the shortest one was in 2001 – 57 days. The warmest autumn was in 2004 when an average daily temperature reached 9.2°С. The most of precipitations in the autumn period is fixed in 2009 – 178 mm, and the least in 2001 – 39 mm. The winter periods were protracted in 2004/05 and 2005/06. Their duration was 114 days. Winter period in 2009/10 with an average daily temperature -7.9°С was the coldest one. The most precipitations are fixed in winter 2005/06 – 208.4 mm, and the least in a winter period 2012/13 are a 52.2 mm. The most of precipitations for a year fell out 777.8 mm in 2012, and the least one in 2011 – 427 mm. The average long-term dates of the beginning of the year seasons are defined. The average long-term date of the beginning of the spring season is on February 27; the summer season is on May 26; the autumn season is on September 14; the winter season is on December 5. Key words: Rivnenskyi Nature Reserve, seasons of the year, precipitation, climatic terms, temperature, long-term date.

scholarly journals Thermohydraulic Performance and Entropy Generation of a Triple-Pass Solar Air Heater with Three Inlets

Energies ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 6399
Author(s):  
Nguyen Minh Phu ◽  
Ngo Thien Tu ◽  
Nguyen Van Hap
Keyword(s):  
Reynolds Number ◽  
Air Temperature ◽  
Entropy Generation ◽  
Solar Air Heater ◽  
Minimum Entropy ◽  
Air Heater ◽  
The Third ◽  
Thermohydraulic Efficiency ◽  
The Difference ◽  
Minimum Entropy Generation

In this paper, a triple-pass solar air heater with three inlets is analytically investigated. The effects of airflow ratios of the second and third passes (ranging from 0 to 0.4), and the Reynolds number of the third pass (ranging from 8000 to 18,000) on the thermohydraulic efficiency and entropy generation are assessed. An absorber plate equipped with rectangular fins on both sides is used to enhance heat transfer. The air temperature change in the passes is represented by ordinary differential equations and solved by numerical integration. The results demonstrate that the effect of the third pass airflow ratio on the thermohydraulic efficiency and entropy generation is more significant than that of the second pass airflow ratio. The difference in air temperature through the collector shows an insignificant reduction, but the air pressure loss is only 50% compared with that of a traditional triple-pass solar air heater. Increasing the air flow ratios dramatically reduces entropy generation. Multi-objective optimization found a Reynolds number of 11,156 for both the airflow ratio of the second pass of 0.258 and airflow ratio of the third pass of 0.036 to be the an optimal value to achieve maximum thermohydraulic efficiency and minimum entropy generation.

scholarly journals THE EARLY SPRING SYNUSIAS IN THE FORESTS OF FAGETO-CARPINETO-QUERCETA ROBORIS SUBFORMATION ON THE TERRITORY OF PRECARPATHIAN REGION (UKRAINE)

2016 ◽  
Vol 1 ◽  
pp. 34-39
Author(s):  
Victoria Gnjezdilova ◽  
Oksana Nespljak ◽  
Vira Bunjak ◽  
Ljubov Makhovska
Keyword(s):  
Early Spring ◽  
Anthropogenic Influence ◽  
The Third ◽  
Gagea Lutea ◽  
Galanthus Nivalis ◽  
Anemone Nemorosa ◽  
Scilla Bifolia ◽  
Herbal Species

Abstract. In the article were presented the results of studying the early spring synusias in the forests of Fageto-Carpineto-Querceta roboris subformation on the Pricarpathian territory. In the studied subformation were separated five associations: Fageto-Carpineto-Quercetum roboris galiosum odorati, Fageto-Carpineto-Quercetum roboris caricetum pilosae, Fageto-Carpineto-Quercetum roboris vincosum, Fageto-Carpineto-Quercetum roboris galeobdolosum, Fageto-Carpineto-Quercetum roboris hederosum. The revealed early spring synusias are formed by the following herbal species: Leucojum vernum L. (Amaryllidacea), Galanthus nivalis L. (Amaryllidacea), Dentaria glandulosa Waldst. et Kit. (Brassicaceae), Anemone nemorosa L.(Ranunculaceae), Scilla bifolia L. (Liliaceae), Isopyrum thalictroides L. (Ranunculaceae), Corydalis cava (L.) Schweigg. Koerte (Papaveraceae) та Gagea lutea (L.) Ker.-Gawl. (Liliaceae). It appears before the leaves blooming and forms the specific white-lilac-blue aspect. Galanthus nivalis L. synusias develops the first and then in the third decade of March develops the group with Anemone nemorosa L. domination. Last years as the result of the negative anthropogenic influence the number of Leucojum vernum L. and Galanthus nivalis L. groups – the rare ephemeroids put to the Ukrainian Red book was abruptly shortened.

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