scholarly journals Grassland communities in the USA and expected trends associated with climate change

2016 ◽  
Vol 69 (2) ◽  
Author(s):  
David Paul Belesky ◽  
Dariusz Piotr Malinowski
Keyword(s):  
Net Primary Productivity ◽  
Weather Conditions ◽  
Anthropogenic Factors ◽  
Plant Resources ◽  
Global Trends ◽  
Temperature And Precipitation ◽  
The Usa ◽  
Grassland Communities ◽  
Growing Conditions

Grasslands, including managed grazinglands, represent one of the largest ecosystems on the planet. Managed grazinglands in particular tend to occupy marginal climatic and edaphic resource zones, thus exacerbating responses in net primary productivity relative to changes in system resources, including anthropogenic factors. Climate dynamism, as evident from the fossil record, appears to be a putative feature of our planet. Recent global trends in temperature and precipitation patterns seem to differ from long-term patterns and have been associated with human activities linked with increased greenhouse gas emissions; specifically CO<span><sub>2</sub></span>. Thus grasslands, with their diverse floristic components, and interaction with and dependence upon herbivores, have a remarkable ability to persist and sustain productivity in response to changing resource conditions. This resistance and resilience to change, including uncertain long-term weather conditions, establishes managed grasslands as an important means of protecting food security. We review responses of grassland communities across regions of the USA and consider the responses in productivity and system function with respect to climatic variation. Research is needed to identify plant resources and management technologies that strengthen our ability to capitalize upon physiological and anatomical features prevalent in grassland communities associated with varying growing conditions.

scholarly journals Information Content of Seasonal Forecasts in a Changing Climate

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Nir Y. Krakauer ◽  
Michael D. Grossberg ◽  
Irina Gladkova ◽  
Hannah Aizenman
Keyword(s):  
Information Gain ◽  
Seasonal Forecasts ◽  
Temperature And Precipitation ◽  
Skill Scores ◽  
The Usa ◽  
Precipitation Anomalies ◽  
The Mean ◽  
Climate Prediction Center

We study the potential value to stakeholders of probabilistic long-term forecasts, as quantified by the mean information gain of the forecast compared to climatology. We use as a case study the USA Climate Prediction Center (CPC) forecasts of 3-month temperature and precipitation anomalies made at 0.5-month lead time since 1995. Mean information gain was positive but low (about 2% and 0.5% of the maximum possible for temperature and precipitation forecasts, resp.) and has not increased over time. Information-based skill scores showed similar patterns to other, non-information-based, skill scores commonly used for evaluating seasonal forecasts but tended to be smaller, suggesting that information gain is a particularly stringent measure of forecast quality. We also present a new decomposition of forecast information gain into Confidence, Forecast Miscalibration, and Climatology Miscalibration components. Based on this decomposition, the CPC forecasts for temperature are on average underconfident while the precipitation forecasts are overconfident. We apply a probabilistic trend extrapolation method to provide an improved reference seasonal forecast, compared to the current CPC procedure which uses climatology from a recent 30-year period. We show that combining the CPC forecast with the probabilistic trend extrapolation more than doubles the mean information gain, providing one simple avenue for increasing forecast skill.

scholarly journals Adaptation of silage maize varieties under extreme northern growing condions in Finland

1979 ◽  
Vol 51 (1) ◽  
pp. 197-209
Author(s):  
Seppo Pulli ◽  
P. M. A. Tigerstedt ◽  
Osmo Kara
Keyword(s):  
Weather Conditions ◽  
Growing Season ◽  
Limiting Factor ◽  
Vegetative Period ◽  
Average Temperature ◽  
Silage Maize ◽  
Maize Varieties ◽  
Growing Conditions ◽  
The University

Trials with maize varieties from various places in the world were started in 1975. In preliminary trials in 1975, 280 varieties were tested. Between 19 and 23 varieties were selected for ordinary variety tests in 1976—78 at the University farm in Siuntio. Weather conditions, particularly average daily temperatures in 1975 were better than the long term averages, and in 1976—78 far below the average growing conditions. Dry matter yields of the seven harvested silage varieties in 1975 varied between 5.8 and 11.5 tons/ha. In 1976—78 the variation in DM yields was 3.8—8.0 tons/ha among 19—23 varieties. In 1975, 44 varieties out of 280 produced mature seed. Only one variety matured in 1978, but none in 1976—77. The developmental stage of silage maize is primarily determined by ear percentage and secondarily by DM %. In 1975 the average ear % of seven varieties was 49.1 %, in 1978 18.1 % and in 1976—77 only 4.0—5.7 % in DM. As a result of the variety tests promising varieties from Yugoslavia, France and Germany could be found. It can be concluded from the long term temperature data that with very early hybrid varieties a mature grain yield can be harvested twice in ten years. Good quality silage material can be harvested six times in ten years and a satisfactory crop can be obtained eight times in then years. The limiting factor for the growth and development of maize in Finland is the low average temperature of the growing season. Important but less significant is the length of the vegetative period, which is determined by the first killing frost in the fall. The temperature deficit is particularly critical at the beginning of the growing season.

scholarly journals Influence of variety and weather conditions on fatty acid composition of winter and spring Camelina sativa varieties in Poland

2020 ◽  
Author(s):  
Danuta Kurasiak-Popowska ◽  
Małgorzata Graczyk ◽  
Anna Przybylska-Balcerek ◽  
Kinga Stuper-Szablewska
Keyword(s):  
Fatty Acids ◽  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Fatty Acid Profile ◽  
Acid Composition ◽  
Weather Conditions ◽  
Camelina Sativa ◽  
Temperature And Precipitation ◽  
Functional Forms

Abstract The aim of this study was to determine the influence of weather conditions over the course of 4 years (2016–2019) on the fatty acid profile of Camelina sativa. It was assumed that varieties and functional forms of plants (spring and winter genotypes) were characterized by a different fatty acid composition and that weather conditions affected the profile of fatty acids in camelina seeds. Statistical analyses were performed based on the results of chemical tests. Differences were found in the mean concentrations of C18:3n3, C18:3n6, C20:2 and C22:1 acids in all genotypes based on the Kruskal test. Two winter genotypes (Maczuga and 15/2/3) and the spring genotype UP2017/02 had the significantly highest content of C18:3n6. Genotypes CSS-CAM31, CSS-CAM30, BRSCHW 28347, CSS-CAM36 and Kirgzkij showed the highest content of C18:3n3. The lowest C18:3n3 content was found in winter genotypes: K9/1, 15/2/3, Przybrodzka (winter form) and C5. It was found that weather conditions deviating from the long-term average, both in terms of temperature and precipitation, did not affect the quantitative profile of fatty acids. Over the 4 years, no differences were observed in the fatty acid profile between the spring and winter forms. Observations made in this study allow to state that spring and winter forms of Camelina sativa retain a constant fatty acid composition regardless of changing weather conditions.

scholarly journals The influence of local climate change on the productivity of spring cereals in the Kirov region

2021 ◽  
Vol 22 (2) ◽  
pp. 244-253
Author(s):  
I. V. Lyskova ◽  
O. E. Sukhoveeva ◽  
T. V. Lyskova
Keyword(s):  
Air Temperature ◽  
Spring Wheat ◽  
Meteorological Data ◽  
Weather Conditions ◽  
Eastern Region ◽  
Positive Trend ◽  
Local Climate ◽  
Temperature And Precipitation ◽  
Spring Cereals

On the basis of long-term meteorological data and research results in a long-term stationary experiment of 1971-2020 a retrospective analysis of changes in air temperature and precipitation in the eastern region of the central climatic zone of the Kirov region was carried out and the influence of these characteristics on the dynamics of the yield of spring cereals was estimated. It has been established that the average annual air temperature during the research period was 2.4±1.0 °C. At the same time, its stable positive trend was observed at the rate of 0.39 °С /10 years. Two decades from 2001 to 2020 were recorded as the warmest for 50 years, when the temperature was 0.7...2.6 °C above climate normal. Selyaninov hydrothermal coefficient (0.7...2.1) testifies to the contrasting conditions of humidification of the vegetation periods during the research years – from drought to excessively humidified. In a long-term experiment, the yield of spring cereals increased in the row wheat – barley – oats: 2.17±0.86, 3.04±0.61, 3.39±0.65 t/ha, respectively. Strong correlations were marked between the average yield (spring wheat) and weather conditions in June: reverse with air temperature (rр = -0.735) and direct with the amount of precipitation (rр = 0.686). It has been established that the use of phosphorus fertilizers (and their aftereffect) in combination with nitrogen-potassium fertilizers weakened the influence of weather conditions on the productivity of spring wheat: the determination coefficients (R2), which reflect the portion of variability due to weather conditions, were 0.59-0.73 for the variant without fertilizers and decreased to 0.50-0.56 when applying NP3K.

scholarly journals Criteria for Abnormality Evaluation of Selected Weather Parameters in the Slovak Republic

2017 ◽  
Vol 63 (2) ◽  
pp. 86-91
Author(s):  
Martin Danilovič ◽  
Helena Hlavatá ◽  
Božena Šoltysová
Keyword(s):  
Air Temperature ◽  
Slovak Republic ◽  
Weather Conditions ◽  
Growing Season ◽  
Cultivated Plants ◽  
Limit Values ◽  
Temperature And Precipitation ◽  
Weather Parameters

Abstract The paper describes the procedure of calculation and assessment of deviations of the average air temperature from the normal (in relation to the normal 1961‒1990) or long-term average and the percentage of normal precipitation or long-term sum of precipitation, valid for the Slovak Republic. Three evaluation tables clearly indicate both threshold limit values, which facilitate the classification of the calculated indices for air temperature and precipitation. Criteria presented in this work are fully applicable for weather conditions evaluation during the growing season of cultivated plants in the Slovak Republic.

scholarly journals Grass pollen seasons in Poland against a background of the meteorological conditions

2015 ◽  
Vol 68 (4) ◽  
pp. 357-365 ◽  
Author(s):  
Dorota Myszkowska ◽  
Katarzyna Piotrowicz ◽  
Monika Ziemianin ◽  
Kazimiera Chłopek ◽  
Katarzyna Dąbrowska-Zapart ◽  
...  
Keyword(s):  
Grass Pollen ◽  
Pollen Season ◽  
Weather Conditions ◽  
Meteorological Conditions ◽  
Daily Maximum ◽  
Temperature And Precipitation ◽  
Pollen Concentrations ◽  
Poaceae Pollen ◽  
Pollen Seasons

The paper refers to the estimation of Poaceae pollen seasons in Poland in selected areas. The aim of the study was to present the long-term variability of the start, end and duration of grass pollen seasons and the seasonal pollen index (SPI) in Poland against a background of the meteorological conditions over pollen seasons. The study was performed in eight Polish cities in 1992–2014 (the common seasons were 2003–2012). Pollen season start was relatively stable in the studied period, the seasons began about the 10th of May, a bit earlier in the south part of Poland. Pollen season ends were more changeable in comparison to the season start and fluctuated from the middle of July to the middle of September. SPI clearly depended on temperature and precipitation in April–August. Daily maximum pollen concentrations were achieved between the end of May and the first decade of July and no evident relationship between this day and weather conditions was found, apart from 2004.

scholarly journals Epizootic Activity of the Central Caucasian High-Mountain Natural Plague Focus

2011 ◽  
pp. 23-26
Author(s):  
A. N. Kulichenko ◽  
Yu. M. Evchenko ◽  
G. A. Mozloev ◽  
M. P. Grigor'ev ◽  
L. V. Lyapustina ◽  
...  
Keyword(s):  
Weather Conditions ◽  
Negative Influence ◽  
Ground Squirrels ◽  
Anthropogenic Factors ◽  
High Mountain ◽  
Anthropogenic Pressure ◽  
Natural Habitats ◽  
Natural And Anthropogenic Factors ◽  
Term Data

Analysis of the long-term data made it possible to identify three periods of epizootic activity of the Central Caucasian high-mountain natural plague focus against the background of the overall downward trend. In the third period (2000-2010) the focus was shown to be under the intense negative influence of natural and anthropogenic factors that stipulated its depression. The natural factors were weather conditions unfavorable for life-sustaining activity of mountain ground-squirrels, the main plague carriers in this focus. Anthropogenic pressure over the focus manifested as follows. The quantity of cattle decreased, that resulted in decrease of territories of the mountain pasturelands, the natural habitats of mountain ground-squirrels. As areas suitable for life-sustaining activity of the mountain ground-squirrel populations reduced, the number of their settlements declined. With account taken for the effect of the anthropogenic influence stated above, short-term and medium-term prognoses of epizootic activity of Central Caucasian high-mountain natural plague focus indicate of rare non-intensive epizooties.

Millet pollen quality depending on the growing conditions and varietal characteristics

2019 ◽  
pp. 59-65
Author(s):  
V. Dryga
Keyword(s):  
Pollen Grains ◽  
Weather Conditions ◽  
Growing Season ◽  
Viable Pollen ◽  
Pollen Quality ◽  
Air Temperatures ◽  
Pollen Formation ◽  
Growing Conditions ◽  
Rock Variety

The aim of the study is to find out the features of forming the quality of pollen grains, namely their size and viability, depending on the growing conditions and varietal characteristics of switchgrass. The research deals with the peculiarities of millet pollen grains formation, depending on the conditions of vegetation and varietal composition, as the pollen quality – its size and viability – affects the seeds germination. It was established that the pollen quality depended both on the conditions of the growing season and varietal composition. Thus, in the 2018 growing season the weather conditions in the flowering phase (July) were favorable for the viable pollen formation, and high temperatures in August, exceeding 35 oC after 11:00 am at the absence of precipitation affected the viability of the pollen. In all the varieties, the viability of pollen was low. The most viable pollen was in the Morozko variety and the least viable – in the Cave-in-Rock variety, which negatively affected the seed germination. Pollen grains are spherical in form and colorless. They were not uniform in size both depending on the genotype and the growing conditions. In 2018 the pollen grains size ranged from 29 to 60 microns, in 2019 – from 5.2 to 57.2 microns. In 2019, the smaller pollen formed compared to 2018 due to high average daily air temperatures that exceeded average daily long-term values and due to significant moisture deficiency. Millet pollen is not homogeneous, depending on the both genotype and vegetation conditions. In 2018, which was favorable for pollen formation, the size varied from 29 to 60 microns, and in the less favorable 2019, it was smaller and ranged from 5.2 to 57.2 microns. The largest size of pollen grains formed in the Sunburst variety compared to other varieties. The most uniform – 85.3 % of the total amount – was the pollen in the Cave-in-Rock variety. Key words: pollen grains, quality, pollen size, viability, pollen form, variability, uniform.

scholarly journals Comparative evaluation of pea selection lines of different morphotypes

2019 ◽  
Vol 49 (5) ◽  
pp. 28-35
Author(s):  
K. S. Temirov
Keyword(s):  
Weather Conditions ◽  
Vegetation Period ◽  
Forest Steppe ◽  
Lodging Resistance ◽  
Northern Forest ◽  
Breeding Lines ◽  
Temperature And Precipitation ◽  
Economically Valuable Traits ◽  
Number Of Seeds

The results of a comparative study of samples of the garden pea (Pisum sativum L.) by the main economically valuable traits are presented. The objects of the research were 13 breeding lines of peas of various morphotypes (leafy, semi-leafl ess, chameleon). The experiment was conducted in 2016–2018 on leached chernozems in the northern forest-steppe of Western Siberia. The study period was characterized by contrasting weather conditions. Uneven precipitation was noted in 2016, which was higher than the norm in May, but below normal in June. In May 2017, the temperature and precipitation corresponded to the long-term average norm. Abundant rainfall from the period of sowing (the fi rst ten-day period of May) to full ripeness (July) and low average daily air temperature in May characterized the vegetation period of 2018. The best results in short-stalk characteristics and lodging resistance were reached by the line of the semi-leafl ess morphotype Nord × Az-318 (57.5 cm) and Orel × Yamal (57.7 cm). An average positive correlation was established between the height of the plant and the number of pods (r = 0.48 ± 0.20). By the mass of 1000 seeds the best results were shown by leafy lines (188.4 g) and the chameleon morphotype (181.1 g). Between the mass of 1000 seeds and the number of seeds in a pod, an average negative correlation was established (r = –0.63 ± 0.25). In terms of the yield, the chameleon morphotype lines (TM-1552, TM-1504) proved the most productive. The average yield of this morphotype was 280.0 g/m2, leafy lines – 271.4 g/m2 and the lines of the semi-leafl ess morphotype – 254.1 g/m2. A correlation was established between the yield and the studied traits. The yield is moderately positively affected by the number of seeds in a pod (r = 0.55 ± 0.20) and the number of pods in a plant (r = 0.50 ± 0.22). A signifi cant yield advantage was not found between the studied breeding lines. For sustainable production of pea seeds, it is advisable to have a system of varieties of different morphotypes.

scholarly journals Influence of Spring Wheat Growing Conditions on Alpha-Amylase Activity in Grain

2021 ◽  
Vol 937 (2) ◽  
pp. 022136
Author(s):  
L Mishchenko ◽  
M Terekhin ◽  
N Terekhin ◽  
A Muratov
Keyword(s):  
Enzyme Activity ◽  
Amylase Activity ◽  
Weather Conditions ◽  
Meteorological Conditions ◽  
Alpha Amylase ◽  
Falling Number ◽  
Average Value ◽  
Temperature And Precipitation ◽  
Phenotypic Manifestation ◽  
Growing Conditions

Abstract The meteorological conditions in which organogenesis stages take place and hydrothermal regime can determine the phenotypic manifestation of quantitative signs, such as, for example, the activity of alpha-amylase. The purpose of our work was to determine what factors (temperature, precipitation, heterothermal coefficient) affect the enzyme activity, at what time of the vegetation, and in what way this influence is evident. The analysis of weather conditions and falling number (FN) for the period from 2011 to 2020 was carried out. Analysis of the FN value over 10 years showed that it can vary from 90 s to 429 s, and at that, the nature of its change is the same, regardless of whether we are considering one variety or the average value for a group of varieties. The correlation coefficient between the FN of a group of varieties and individual FN is 0.94-0.98. Generally, during the vegetation season, the alpha-amylase activity was influenced to a greater extent by the amount of precipitation than by temperature. This dependence is negative - an increase in precipitation leads to a decrease in the FN, and, consequently, to an increase in the enzyme activity. However, it was found that in different phases of ontogeny the influence of temperature and precipitation can be diametrically opposite.

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