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Agronomy ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 205
Author(s):  
Lauren E. Parker ◽  
Ning Zhang ◽  
John T. Abatzoglou ◽  
Steven M. Ostoja ◽  
Tapan B. Pathak

Every decade, a suite of standardized climatological metrics known as climate normals are updated, providing averages of temperature and precipitation data over the previous 30-year period. Although some of these climate normals are directly applicable to agricultural producers, there are additional agroclimate metrics calculated from meteorological data that provide physiologically relevant information for on-farm management decisions. In this study, we identified a suite of energy-based agroclimate metrics and calculated changes over the two most recent normal periods (1981–2010 and 1991–2020), focusing on specialty crop production regions in California. Observed changes in agroclimate metrics were largely consistent with broader global warming trends. While most metrics showed small changes between the two periods, during the 1991–2020 period, the last spring freeze occurred ~5 days earlier as compared to the 1981-2010 period, contributing to a >6 day longer frost-free period in the Sacramento and Salinas Valleys; likewise an additional 6.4 tropical nights (Tn > 20 °C) occurred in the Coachella Valley during the 1991-2020 period. A complementary trend analysis of the agroclimate metrics over the 1981–2020 period showed significant increases in growing degree days across all agricultural regions, while significant increases in heat exposure were found for the Salinas and Imperial Valleys and over the Central Coast region. Moreover, summer reference evapotranspiration increased approximately 40 mm in California’s Central Valley during 1981–2020, with implications for agricultural water resources. Quantifying the shifts in these agroclimate metrics between the two most recent 30-year normal periods and the accompanying 40-year trends provides context for understanding and communicating around changing climatic baselines and underscores the need for adaptation to meet the challenge that climate change poses to agriculture both in the future and in the present.


2021 ◽  
pp. 53-56
Author(s):  
N. Yu. Antipova ◽  
E. V. Kashnova

Relevance. In Siberia, sweet pepper is grown both in the open and in the protected ground. For a short Siberian summer, it is important to have varieties adapted to the local bioclimatic potential: early ripening, for obtaining valuable products in the middle of summer, and the possibility of conducting seed production. The priority direction is the creation of varieties that are resistant to abiotic and biotic environmental factors, with high yield, product quality, and high vitamin C content.Materials and methods. The research was carried out in film unheated greenhouses and in the open ground at the West Siberian Vegetable Experimental Station-a branch of the Federal Research Center for Vegetable Growing. The material for research was collected, selected samples, varieties of pepper.Results and discussion. Breeding work on the culture of sweet pepper at the West Siberian Vegetable Experimental Station was started in the late 60s of the last century, active work – in the early 90s. The conditions of the sharply continental climate, with its mild frost-free period, require the creation of varieties capable of obtaining a commercial pepper crop, despite the negative impact of biofactors. The use of precocious varieties gives a guaranteed harvest by avoiding early autumn frosts. Breeding for precocity is one of the main directions of Siberian breeding. Over the years of selection, models of future varieties were created, more than 20 varieties of sweet pepper of various varietal types were created. The varieties obtained at the station all belong to the early-maturing group, with a period from germination to the first fruit harvest-98-116 days, a height of 40-80 cm during the fruiting period, compact, suitable for growing without a garter to the trellis. As a result of a comprehensive assessment of the initial breeding material, donors of economically valuable traits were selected, the inclusion of which in the breeding process contributed to the creation of a number of precocious pepper varieties of various variety types. The created varieties have a high biological potential in terms of adaptability, productivity, and biochemical parameters. Suitable for growing in various production sectors.


2021 ◽  
Vol 13 (15) ◽  
pp. 8491
Author(s):  
Abelardo García-Martín ◽  
Luis L. Paniagua ◽  
Francisco J. Moral ◽  
Francisco J. Rebollo ◽  
María A. Rozas

Climate change is having many effects in the agricultural sector, which are being studied worldwide. Undoubtedly, warmer winters and earlier springs produce changes in frost regimes and severity that will affect the sustainability of agricultural production in the area. The Mediterranean region and the Iberian Peninsula (IP) are among the areas where the greatest impact of climate change is expected. Daily data from 68 weather stations of the IP belonging to the European Climate Assessment and Dataset (1975–2018) were used to conduct a spatiotemporal study of the frost regime. The variables calculated include the probability of three frost types according to their severity, frost day, mean absolute minimum yearly temperature, first frost day, last frost day, and frost-free period. These variables were integrated into a geographic information system, which allowed the graphical visualization of their patterns using of geostatistical interpolation techniques (kriging). Changes in frost variables were investigated using the Mann–Kendall test and Sen’s slope estimator. A general reduction in the number of frosts per year is observed (values between −0.04- and −0.8-day frosts per year), as well as an increase in the mean absolute minimum temperature (values between 0.04 and 0.10 °C per year), with very high significant trends throughout the territory. The reduction in the number of frosts is more pronounced at a higher elevation. Frost dates vary greatly due to the orographic characteristics of the IP. The generalized trend is of a significant delay of the autumn frosts (values between 0.4 and 1.06 days/year), as well as early spring frosts (between −0.429 and −1.29 days/year), and as a consequence a longer frost-free period, all changes were much stronger than those found in other regions of the world. These effects of climate change must be mitigated by modifying species, varieties, and cultivation techniques to guarantee sustainable agriculture.


Agriculture ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 573
Author(s):  
Czesław Koźmiński ◽  
Jadwiga Nidzgorska-Lencewicz ◽  
Agnieszka Mąkosza ◽  
Bożena Michalska

The ongoing climate warming affects, among others, and the variability of thermal conditions in spring and autumn are resulting in earlier dates of the beginning and end of the growing season. The present paper provides detailed characteristics of the phenomenon of ground frosts, addressing the question of whether the risk of frost-related damage in the extending growing season is still present. The assessment of temporal and spatial distribution of ground frosts (5 cm above ground level-AGL) in Poland in the thermal growing season (AT > 5 °C) was conducted on the basis of the results of air temperature measurements at 5 and 200 cm a.g.l. obtained from 52 station of the Institute of Meteorology and Water Management—National Research Institute for the period 1971–2020. The thermal growing season was calculated using the method by Gumiński. The following were calculated: the dates of the occurrence of ground frosts in spring and autumn, duration of the frost-free period, the number of days with frosts of various intensity, according to years, ten-day period and days in a year together with trends of change. The conducted analysis demonstrated that the number of days with frosts in the thermal growing season in the multiannual period under analysis (1971–2020) does not show any statistically significant changes. It was found that in the thermal growing season, the average number of days with ground frosts in Poland amounts to 28 and ranges in spring from 15 to 22, and in autumn from 8 to 12. Most frequently, approx. 49%, slight frosts are recorded, followed by moderate (29%), severe (15%) and very severe (7%). A positive effect of water reservoirs on decreasing the frequency and intensity of frosts, as well as sporadic occurrence of the phenomenon in the second half of June were demonstrated. Statistically significant earlier dates of disappearance of frosts in spring, later dates of occurrence in autumn and the lengthening of the frost-free period from approximately 2 days in the north-east of Poland to approximately 8.0 days over 10 years in the Pomerania region, create increasingly more favourable conditions for the cultivation of plants with high thermal requirements in Poland.


2021 ◽  
Author(s):  
Karel Jedlička ◽  
Pavel Hájek ◽  
Tomáš Andrš ◽  
Otakar Čerba ◽  
Jiří Valeš ◽  
...  

<p><span>Our contribution presents a prototype of Agroclimatic atlas - a web map application, presenting agroclimatic factors: </span><span>Frost-free period, </span>Water balance, Total precipitation, Total solar radiation, Last date with soil temperature above 10 °C for nitrogen application, Number of days with growing temperatures for a crop, Number of days with optimal growing temperatures for a crop HSU - Heat stress units for a crop, <span>The factors are calculated based on algorithms described in </span><em><span>Calculation of Agro-Climatic Factors from Global Climatic Data</span></em><span> (Jedlička et al. 2021, doi:  </span><span>10.3390/app11031245</span><span>).</span></p><p><span>The agroclimatic atlas application aims to provide a comprehensive overview of agriculture-related climatic characteristics of an area of interest in a time retrospective.  The application can be used by both an individual farmer or a precision farming expert exploring a wider area.</span></p><p><span>The principal source of climatic variables (such as temperature, rainfall, evaporation, runoff, and solar radiation) used in the atlas is the </span><span>ERA5-Land dataset</span><span> (available as the </span><span>Copernicus Climate Change Service (C3S) at its Climate Date Store</span><span>). </span></p><p><span>The contemporary version of the Agroclimatic Atlas application is accessible from here https://www.mdpi.com/2076-3417/11/3/1245#</span><span>. This version is in Czech only and portrays data from Czechia 10 years backward. However, the application is under ongoing development driven by the H2020 projects </span><span>Stargate</span><span>, </span><span>Sieusoil</span><span>, and </span><span>Smartagrihubs</span><span>. Therefore a newer version will be presented at the conference. The first design concepts can be seen in the figure below.</span></p><p><img src="https://contentmanager.copernicus.org/fileStorageProxy.php?f=gnp.475eafd0808065334309161/sdaolpUECMynit/1202SME&app=m&a=0&c=31dbfa2ddfd3719b82491d259ccc4117&ct=x&pn=gnp.elif&d=1" alt=""></p><p>Figure 1. - Mockup of Agroclimatic atlas application, accessible from https://xd.adobe.com/view/65199b72-db2f-420a-aee2-bc90dc83aaea-304a/</p>


2020 ◽  
Vol 9 (3) ◽  
pp. 67-72
Author(s):  
Anastasiya A. Zorina ◽  
Elena A. Shuyskaya

The paper considers dynamics of phenological phenomena of animals in the south taiga Central Forest biosphere reserve. As initial data we used materials of meteorological and phenological observations made under the program of maintaining the nature chronicle on the basis of the meteorological post Forest reserve in the Roshydromet network. Of the 46 meteorological series only ten (22%) show significant long-term changes over the period 19902019: an increase in the average annual air temperature, temperature in May, August, September and November; a decrease of total precipitation in September and an increase in December; a positive displacement of occurrence dates of maximum temperature less than 0C and the final formation of ice on the pond, a negative shift of the phenological summer beginning dates. The authors prove that there has been a shift of time when winter comes or an increase in the duration of the frost-free period on the reserve territory over a 30-year period. For the spring phenodates of the considered animal species, there is a negative long-term linear trend in the variability of phenological phenomena towards an earlier start of events. Such signs as the first meeting of the small tortoiseshell, the first bites of the biting mosquito, the first appearance of the grass frog and the viviparous lizard are recommended to be used as indicators of the climate change. The shift of insect and amphibian phenodates is associated with a shortening of the cold season in the reserve climate system. A significant change of lizards phenological phenomenon time is caused by abiotic as well as by biotic (forage) factors.


2020 ◽  
pp. 30-32
Author(s):  
И.В. Тимошенко ◽  
Н.В. Гераськина ◽  
А.А. Рубцов ◽  
Н.Н. Степанов

В последние десятилетия требования к новым сортам и гибридам репчатого лука существенно возрастают. Современные сорта и гибриды лука репчатого должны обладать стабильными проявлениями основных хозяйственно ценных признаков при разных условиях выращивания. Приоритетное направление в селекции лука репчатого – не только селекция на продуктивность, но и на скороспелость, пригодность к транспортировке, которые включают в себя комплекс признаков (округлая форма луковицы, ее плотность, прочность прикрепления кроющих сухих чешуй). Важный признак – лежкость луковиц при хранении, для чего ведется селекционная работа на высокое содержание сухого вещества и сахарозы. Цель работы – создать новые сорта и гибриды лука репчатого для юга России с комплексом хозяйственно полезных признаков. Исследования проводили в 2015–2020 годах в открытом грунте на Бирючекутской овощной селекционной опытной станции – филиал ФГБНУ ФНЦО, расположенной в Ростовской области. Почвы в опытах – черноземы обыкновенные. Мощность гумусового горизонта 70 см. Содержание гумуса в пахотном слое 4,2%. Погодные условия в годы проведения опытов были типичными для климатической зоны юга России. Климат – континентальный, с безморозным периодом более 260 дней, жарким и засушливым летом и относительно короткой и теплой зимой. За годы исследований был собран разнообразный материал из разных регионов мира. Собранные сорта и гибриды оценивали по наличию ценных признаков и свойств, на их основе создавали линейный материал источников и доноров признаков, востребованных в селекционных программах. Из лучших линий сформирован банк источников и доноров наиболее важных признаков – коллекция в количестве 100 образцов. Среди изученных образцов лука репчатого были выделены генисточники ценных признаков для различных направлений селекции культуры в условиях юга России. Наиболее устойчивые к региональным стрессам генотипы включали в гибридизацию, а также на их основе создавали линейный материал. Параллельно шла сортовая и гетерозисная селекция. По результатам конкурсного испытания выделился образец GL-5 Л 40 (Титан), который был передан в Государственное сортоиспытание. In recent decades, the requirements for new varieties and hybrids have increased significantly. Modern varieties and hybrids of onion should have stable manifestations of the main economic and valuable characteristics under different growing conditions. Priority areas in the selection of onions are not only selection for productivity, but also for precocity, suitability for transportation, which include a set of characteristics (the rounded shape of the bulb, its density, the strength of attachment of the covering dry scales). An important feature is also the keeping quality of bulbs during storage, for which breeding work is conducted for a high content of dry matter and sucrose. The aim of this work is to create new varieties and hybrids of onion for the South of Russia with a complex of economically useful characteristics. The study was performed on Birutchecutskaya Vegetable Experimental Station – branch of FSBSI FSVC, located in the Rostov region in 2015–2020 in the open field. The soils in the experiments are ordinary black earth. The thickness of the humus horizon is 70 cm. The humus content in the arable layer is 4.2%. Weather conditions during the experiments were typical for the climate zone of southern Russia. The climate is continental, with a frost-free period of more than 260 days, hot and dry summers, and relatively short and warm winters. Over the years of research, various materials from different regions of the world have been collected. The collected varieties and hybrids were evaluated based on the presence of valuable traits and properties on their basis, a linear material of sources and donors of traits that are in demand in breeding programs was created. From the best lines, a bank of sources and donors of the most important features is formed – a collection of 100 samples. Among the studied onion samples, sources of valuable traits for various areas of culture selection in the South of Russia were identified. The most resistant genotypes to regional stresses were included in hybridization, and linear material was created on their basis. In parallel, there was varietal and heterosis selection. According to the results of the competitive test, a sample of GL-5 L 40 (Titan) was produced, which was transferred to the State variety testing.


Author(s):  
Felix O Oboite ◽  
Philip G Comeau

Abstract In the face of anticipated climate change, growth models require modifications to effectively model likely future growth and survival of trees and stands. To support incorporation of climate effects in the Mixedwood Growth Model (MGM), we developed climate-sensitive mixed effects models for lodgepole pine (Pinus contorta Douglas ex Loudon), jack pine (Pinus banksiana Lamb.), trembling aspen (Populus tremuloides Michx.), balsam poplar (Populus balsamifera L.) and white spruce (Picea glauca (Moench) Voss), and examined how tree size, intra- and interspecific competition and climate will influence individual-tree diameter growth. Remeasurement data from permanent growth and yield sample plots from across the western Canadian boreal forest were used for this study. Based on the model that we developed, tree size, competition and climate had varying effects on growth, among tree species. Although intraspecific competition had a stronger negative effect on growth for deciduous and white spruce trees, interspecific competition had a stronger negative effect on the growth of pine. Deciduous trees growing in stands having longer frost-free period experienced an increase in growth but a negative effect of frost-free period was observed for conifers. In addition, higher moisture was found to increase tree growth, but the influence of available moisture on growth was dependent on competition. Overall, these results suggest that, under climate warming, between-species differences in growth responses will contribute to our understanding of the stand dynamics in the western boreal region of Canada. Climate sensitive growth models developed in this study will be useful in the recalibration of MGM and other individual-tree models, and predictions will contribute to better-informed decisions about silvicultural treatments for these economically important boreal tree species.


2020 ◽  
Vol 3 (4) ◽  
Author(s):  
Tatiana L. Ananina ◽  
Alexander A. Ananin

Due to global climate change it is important to constantly monitor the current climate state, observed trends and timely detection of their changes. The change in the hydrothermal regime has to result into changes in natural ecosystems. The analysis of long-term changes of mean annual temperatures and annual precipitation in warm and cold seasons over 1955-2017 years was carried out using data of the Davsha meteorological station , 54, 35˚N., 109,5˚E. Significant warming in the Northern Baikal region has been observed since 1990 and continues to the present. The climate is subcontinental with cool and short summers, frosty and long winters. In the last decade, there has been a shift of the beginning some phenology seasons. This had an effect on the increase in the warm season of the year and the duration of the frost-free period (by 5 days from the long-term average date). Spring comes earlier - for 3 days, summer and the last frost - for 5 days, autumn comes later - for 2 days.


2020 ◽  
Vol 15 (8) ◽  
pp. 1077-1084
Author(s):  
L.D. Urazova ◽  
◽  
O.V. Litvinchuk ◽  

Experimental selection studies were carried out in 2016-2018. in the fields of the Narym Department of Breeding and Seed Production of the Siberian Research Institute of Agriculture and Peat (Kolpashevo, Tomsk Region). The purpose of the research was to study collection samples of lawn grasses capable of effectively using the agro-resource potential of the naturaland climatic conditions in the taiga zone of the Tomsk region. The climate in the research area is sharply continental with long, severe winters and short, but hot and often dry summers. The snow cover lasts about seven months (usually from October to April). The frost-free period is short. Annual precipitation is about 500 mm, including more than 300 mm during the growing season. The sum of air temperatures above 10° C is 1300-1600° C. The soils of the experimental plots are sod-podzolic, sandy loam in granulometric composition, with a humus content in the arable horizon of no more than 2%. As experimental material, 21 samples of bluegrass of three species were studied (8 domestic and 13 foreign varieties); 21 samples of pasture ryegrass (domestic varieties - 3, foreign - 18); 10 samples of four species of bent field of foreign origin; 12 samples of five types of fescue (domestic varieties – 5, foreign – 7). Among the experimental cultivars, the following sources of economically valuable traits were identified: high winter hardiness - all investigated cultivars of bluegrass, bent grass, fescue; grade of perennial ryegrass Yuventus (Denmark); short stature - varieties of meadow bluegrass Yaskia, Limonsine (Germany), Barkenta (Netherlands); ryegrass cultivars of pasture Sport (Poland), Fiesta (USA), Yuventus (Denmark); bentgrass wild populations from Mongolia (K14272, K-14273) and bentgrass from Ukraine (K14265); fine texture source - perennial ryegrass varieties Yuventus, Denmark, Primevere, France, K-14233, Poland.


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