Predicting germination capacity of Pinus sylvestris and Picea abies seeds using temperature data from weather stations

1998 ◽  
Vol 28 (10) ◽  
pp. 1530-1535 ◽  
Author(s):  
Curt Almqvist ◽  
Urban Bergsten ◽  
Lennart Bondesson ◽  
Urban Eriksson
Keyword(s):  
Picea Abies ◽  
Pinus Sylvestris ◽  
Meteorological Data ◽  
Growing Season ◽  
Geographic Area ◽  
Mature Seed ◽  
Parameter Estimates ◽  
Germination Capacity ◽  
Degree Days ◽  
Weather Stations

In Fennoscandia, both Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) often fail to produce mature seed, especially in the northern parts of their range. Therefore, cone and seed crop predictions are of major strategic importance for maintaining sustainable multipurpose forestry. We present functions for predicting germination capacity of Pinus sylvestris and Picea abies seed over a wide geographic area. The functions are based on germination analyses for 1297 Pinus sylvestris and 597 Picea abies natural stands in Sweden during 1971-1994. Meteorological data from 71 weather stations were used to calculate heat sums with threshold values from 4 to 10°C and two durations of growing season (ending August 31 or September 30). Logistic regression was utilised for parameter estimates. Accumulated heat sum (threshold 5°C) from start of growing season until August 31 in combination with number of days from estimated time of fertilisation until approximate time for embryo growth cessation gave the best function. The function shows that Picea abies has lower temperature requirements for producing mature seed than Pinus sylvestris. A germination capacity of 95% is reached at a heat sum of 875 degree-days for Picea abies and at 975 degree-days for Pinus sylvestris.

Combined effects of site preparation, soil properties, and sowing date on the establishment of Pinus sylvestris and Picea abies from seeds

2003 ◽  
Vol 33 (5) ◽  
pp. 931-945 ◽  
Author(s):  
Michelle de Chantal ◽  
Kari Leinonen ◽  
Hannu Ilvesniemi ◽  
Carl Johan Westman
Keyword(s):  
Soil Moisture ◽  
Picea Abies ◽  
Pinus Sylvestris ◽  
Soil Properties ◽  
Seedling Emergence ◽  
Growing Season ◽  
Sowing Date ◽  
Site Preparation ◽  
Winter Mortality ◽  
Frost Heaving

The aim of this study is to determine the effect of site preparation on soil properties and, in turn, the emergence, mortality, and establishment of Pinus sylvestris L. (Scots pine) and Picea abies (L.) Karst. (Norway spruce) seedlings sown in spring and summer along a slope with variation in soil texture and moisture. Three site preparation treatments of varying intensities were studied: exposed C horizon, mound (broken L–F–H–Ae–B horizons piled over undisturbed ground), and exposed Ae–B horizons. Seedling emergence was higher in the moist growing season than in the dry one. During a dry growing season, mounds and exposed C horizon had negative effects on soil moisture that increased mortality. Moreover, frost heaving was an important cause of winter mortality on mounds and exposed C horizon, whereas frost heaving was low on exposed Ae–B horizons, even though soil moisture and the content of fine soil particles (<0.06 mm) were high. Frost heaving mortality was higher for summer-sown than for spring-sown seedlings and for P. abies than for P. sylvestris. Growing season mortality was high following a winter with frost heaving, suggesting that roots were damaged, thereby making seedlings more susceptible to desiccation.

scholarly journals Testing of germination of spruce, pine and larch seed after 10 years from collection

2014 ◽  
Vol 60 (No. 12) ◽  
pp. 540-543
Author(s):  
I. Tomášková ◽  
J. Vítámvás ◽  
J. Korecký
Keyword(s):  
Czech Republic ◽  
Picea Abies ◽  
Pinus Sylvestris ◽  
Tree Species ◽  
Abiotic Factors ◽  
Forest Tree ◽  
Germination Capacity ◽  
The Czech Republic ◽  
Germination Energy ◽  
Seed Ageing

:Germination capacity and germination energy are usually the most frequently used quantitative parameters of forest tree seed. With seed ageing both parameters decreased and the rate of the collapse is given by tree species, age of tree and its seed and biotic and abiotic factors. Relatively little attention has been paid to the age of seed. As it was found, the longevity of the main tree species remained relatively high, and spruce (Picea abies [L.] Karsten and pines (Pinus sylvestris L.) from the investigated areas across the Czech Republic maintained minimally one third of germination capacity or germination energy during the 10 years with the exception of larch (Larix decidua Mill.) where germination capacity decreased almost to zero after 10 years. Although the germination energy and germination capacity decreased significantly, it is possible to use the seed in the case of shortage of the seed of better quality. &nbsp;

scholarly journals Influence of meteorological factors on the formation of radial growth of trees in coniferous stands of the Leningrad region

2020 ◽  
Author(s):  
А.В. Чудаков ◽  
Д.А. Данилов ◽  
Д.А. Зайцев
Keyword(s):  
Picea Abies ◽  
Pinus Sylvestris ◽  
Climatic Factors ◽  
Rank Correlation ◽  
Growing Season ◽  
Growth Conditions ◽  
Monthly Precipitation ◽  
Leningrad Region ◽  
Spruce Wood ◽  
The Impact

Проведено исследование влияния климатических факторов на показатели прироста древостоев сосны (Pinus sylvestris) и ели (Picea abies) естественного происхождения, не затронутых рубками. Объекты исследования – древостои с разной долей участия этих пород в однородных условиях произрастания на почвах с двучленными отложениями. Длительность анализируемого периода составила 54 года, на текущий момент древостои являются спелыми. Была изучена связь прироста со средней температурой воздуха за вегетационный период и суммой осадков за вегетационный период. Анализ связей климата с параметрами древесины хвойных проводили на основе поиска статистически значимых ранговых коэффициентов корреляции между древесно-кольцевыми хронологиями и климатическими факторами в насаждениях с разной долей участия сосны и ели. Вычислялся коэффициент ранговой корреляции Спирмена как количественная оценка связи между исследуемыми явлениями. Ранговый корреляционный анализ позволил на статистически значимом уровне оценить вклад средних температур и суммы осадков по месяцам в формирование макроструктурных элементов древесины сосны и ели. Прослеживается большая метеозависимость элементов годичного прироста древесины ели, чем сосны, в данных условиях. Для соснового элемента смешанных хвойных древостоев наибольшая взаимосвязь с температурными показателями наблюдается в июле–сентябре, тогда как для ели выявлена ярко выраженная зависимость с этим фактором в мае для всех древостоев с ее участием. Проведенное исследование показало, что в зависимости от доли участия ели и сосны образование структурных элементов ксилемы годичного прироста имеет разную степень по силе вязи со средними температурами и суммой осадков по месяцам вегетационного периода. A study was carried out on the impact of climatic factors on the increment rates of pine (Pinus sylvestris L.) and spruce (Picea abies (L.) Karst.) stands of natural origin, not affected by forestry impact. Tree stands with different participation of these species in similar growth conditions on binary deposits soils were reviewed. The duration of the analyzed period was 54 years, at the present time stands are mature. The connection between the growth and average air temperature during the growing season and the amount of precipitation during the growing season was studied. The analysis of climate relationships with coniferous wood parameters was carried out on the basis of searching statistically significant rank coefficients of correlation between wood-ring chronologies and climate factors in stands with different participation shares of pine and spruce. Spearman's rank correlation coefficient was calculated as a quantitative evaluation of the connection between the observed effects. Rank correlation analysis allowed to estimate at statistically significant level the contribution of average temperatures and the sum of monthly precipitation on the formation of macrostructural elements of pine and spruce wood. There is a higher meteorological dependence on the increment rate of spruce wood than pine wood in the given conditions. For the pine element of mixed coniferous trees the greatest correlation of increment with temperature indices is observed in July-September months, while for the spruce a marked dependence with this factor was revealed in May month for all stands with spruce participation. The study showed that depending on the share of conifers, the formation of structural elements of the xylem has a different strength of the relationship with average temperatures and the amount of precipitation in the months of the growing season.

scholarly journals Base temperature as a function of genotype: a foundation for modeling phenology of temperate fruit species

2016 ◽  
Vol 37 (4) ◽  
pp. 1811
Author(s):  
Anzanello Rafael ◽  
Luiz Antonio Biasi
Keyword(s):  
Meteorological Data ◽  
Growing Season ◽  
Fruit Trees ◽  
Thermal Time ◽  
Base Temperature ◽  
Degree Days ◽  
Single Node ◽  
Fruit Species ◽  
Lower Base ◽  
Phenological Phases

To complete each phase of the growing season, plants must accumulate thermal time at lower base temperature (Tb). Little information exists on Tb variation between either fruit species or cultivars of the same species. We therefore aimed to determine the lower base temperature for contrasting genotypes in precocity of peach, plum, grape, pear, and kiwi. Twigs 25-35 cm long for the following cultivars: peach, Tropic Beauty (TB) and Eragil (ER); plum, Gulf Blaze (GB) and Letícia (LE); grape, Chardonnay (CH) and Cabernet Sauvignon (CS); pear, Smith (SM) and Packham’s (PA); and kiwi, Golden King (GK) and Hayward (HA) were collected in orchards in Veranópolis, RS Estate, on 06/13/2014, with 0 h at temperatures ? 7.2°C (chilling hours; HC) in the field. Intact twigs packed in black plastic film were subjected to 1,008 HC at 0°C in incubators to overcome dormancy and then transferred to temperatures of 2, 4, 6, 8, 10, and 12°C on single-node cuttings planted in phenolic foam to define effective heat temperature for the genotypes. Over 110 d, budburst of the buds was evaluated in 2-3-d intervals in the green-tip stage. The resulting inverse data of number of days to budburst (1/days to budburst) was inserted into regression curves to estimate Tb for each genotype. Historical phonological series comprised of 10 years for the analyzed cultivars and meteorological data of the cultivation sites were used to determine thermal time (degree-days) for the fruit trees during the growing season, considering different phenological phases. Temperate fruit species exhibited different Tb behaviors: Tb was lower for early cultivars (TB and GB = 2.2°C; CH = 2.1°C; SM = 4.4°C; GK = 4.3°C) and higher for late cultivars (ER = 6.3°C; LE = 6.2°C; CS = 4.3°C; HA and PA = 8.2°C) for all cultures. The Tb f fruit cultivars related directly with genotype chilling requirements: the higher the chilling requirement, the higher the Tb of the cultivar. Cultivars of the same fruit species yielded a sum of degree-days almost equal to finalize the growing season, regardless of the degree of precocity (TB = 1720; ER = 1801; GB = 1680; LE = 1718; CH = 2310; CS = 2369; SM = 2096; PA = 2003 GD; GK = 2775; HA = 2691). Regarding phenological phases, 82% of the assessed cases responded more to thermal time (degree-days) than to chronological time (d) to complete phenological steps. Differences in Tb between genotypes are a relevant factor for improving the accuracy and applicability of phenology models in agriculture.

Applications of the herbicide sethoxydim increase wheat yield in the absence of weeds

1996 ◽  
Vol 36 (5) ◽  
pp. 555
Author(s):  
ID Black ◽  
CB Dyson ◽  
AR Fischle
Keyword(s):  
Leaf Growth ◽  
Wheat Yield ◽  
South Australia ◽  
Growing Season ◽  
Degree Days ◽  
Experimental Site ◽  
Yield Increase ◽  
Growing Seasons ◽  
Positive Linear Correlation ◽  
Area North

In 11 experiments over 6 seasons the herbicide sethoxydim was applied to Machete, Spear and Blade wheat cultivars in the absence or near absence of weeds (10 sites) or where the weeds were controlled by selective herbicides (1 site), in the cropping area north of Adelaide, South Australia. The rates applied included 9-47 g a.i./ha at the 2-3 leaf growth stage and 9-74 g a.i./ha at early tillering. Except for the very long growing season of 1992, there was a highly significant positive linear correlation between the number of degree days in the growing season at each experimental site and relative mean yield increase of these sethoxydim treatments. Yield increases ranged from nil in growing seasons of about 1000 degree days to 32% in a growing season of 1480 degree days, with a median of 8% over the experiments.

scholarly journals Reconstruction of the annual balance of Vadret da Morteratsch, Switzerland, since 1865

2009 ◽  
Vol 50 (50) ◽  
pp. 126-134 ◽  
Author(s):  
Johanna Nemec ◽  
Philippe Huybrechts ◽  
Oleg Rybak ◽  
Johannes Oerlemans
Keyword(s):  
Meteorological Data ◽  
Balance Model ◽  
Surface Energy Fluxes ◽  
Temperature And Precipitation ◽  
Continuous Mass ◽  
Weather Stations ◽  
Precipitation Records ◽  
High Elevations ◽  
Annual Balance ◽  
Almost Continuous

AbstractWe have reconstructed the annual balance of Vadret da Morteratsch, Engadine, Switzerland, with a two-dimensional energy-balance model for the period 1865–2005. The model takes into account a parameterization of the surface energy fluxes, an albedo that decreases exponentially with snow depth as well as the shading effect of the surrounding mountains. The model was first calibrated with a 5 year record of annual balance measurements made at 20 different sites on the glacier between 2001 and 2006 using meteorological data from surrounding weather stations as input. To force the model for the period starting in 1865, we employed monthly temperature and precipitation records from nearby valley stations. The model reproduces the observed annual balance reasonably well, except for the lower part during the warmest years. Most crucial to the results is the altitudinal precipitation gradient, but this factor is hard to quantify from the limited precipitation data at high elevations. The simulation shows an almost continuous mass loss since 1865, with short interruptions around 1920, 1935 and 1980. A trend towards a more negative annual balance can be observed since the beginning of the 1980s. The simulated cumulative mass balance for the entire period 1865–2005 was found to be –46mw.e.

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