Wintertime atmospheric pollutants—Do they affect the performance of deciduous trees in the ensuing growing season?

We collected foliage from 34 species of broad-leaved, deciduous trees in southern Ontario and determined an index of leaf toughness, weight per unit area, percent water, and percent of dry weight as available carbohydrate, crude fibre, hemicellulose, holocellulose, lignin, polyphenols, nitrogen, phosphorus, ash, potassium, calcium, and magnesium. We analyzed variation in these constituents within samples, among three sampling periods during one growing season, and among species.

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No risk - no fun: The tradeoff between avoiding frost and maximizing growth

10.5194/egusphere-egu2020-21586 ◽

2020 ◽

Author(s):

Frederik Baumgarten ◽

Yann Vitasse ◽

Arthur Gessler

Keyword(s):

Prunus Avium ◽

Light Transmission ◽

Growth Parameters ◽

Growing Season ◽

Deciduous Trees ◽

Season Length ◽

Freezing Resistance ◽

Spring Frost ◽

Growing Season Length ◽

Temperature Thresholds

AbstractLeaf-out timing is crucial for the fitness of deciduous trees inhabiting temperate and higher latitudes. Optimal leaf-out allows minimizing freezing damages and herbivory pressure while maximizing growing season length and resource uptake in order to increase their competitiveness. However only a few attempts have been made to classify species according to their strategy along this trade-off.Using climate chambers, we artificially provoked 5 different flushing dates that span the maximum possible range of natural occurring flushing dates of 4 tree species (Prunus avium, Carpinus betulus, Fagus sylvatica and Quercus robur). Shortly after each of the five leaf-out timings, 12 saplings per species were exposed to a frost treatment that is expected to either kill all leaves (LT100, i.e. lethal temperature killing 100% of the leaves) or to partially damage them. These temperature thresholds have been adapted to each species according to their freezing resistance found in the literature. A subset of 12 indviduals per species served as a control and were not subjected to a frost treatment. Shortly after the frost treatment, all saplings were planted outside in the ground under a shading net (~-60% of light transmission) simulating below canopy conditions at the WSL research facility near Z&#252;rich.Growth parameters (diameter, height) and recovery state (percentage of greenness compared to the control) were regularly measured during the consecutive growing season as well as the leaf coloring in autumn 2019. Preliminary results suggest that cherry and oak have recovered more than 80% by the end of the growing season, whereas beech and hornbeam only recovered about 50%. Oak was the fastest species to recover, already reaching 80% three weeks after the frost treatment. Our results allow to better quantify to what extend damaging spring frost reduces competitiveness for resources (light, nutrients) among species.

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SUNBATHED ASPEN GROW TO SHOW HOW SUNLIGHT INFLUENCES ASPEN LEAF CHANGES IN THE AUTUMN SEASON

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xliv-m-2-2020-105-2020 ◽

2020 ◽

Vol XLIV-M-2-2020 ◽

pp. 105-110

Author(s):

S. K. Weidler ◽

R. Sivanpillai

Keyword(s):

Populus Tremuloides ◽

Color Change ◽

Growing Season ◽

Environmental Modeling ◽

University Of Wyoming ◽

Learning Activity ◽

Deciduous Trees ◽

Leaf Color ◽

Inquiry Based Learning ◽

Observation Network

Abstract. Every autumn, leaves of deciduous trees change from green to other colors and eventually drop to the ground. The rate of color change is influenced by a several factors including the amount of sunlight and temperature. As part of an inquiry-based learning activity, University of Wyoming students have been recording leaf color change (% change) and its drop date (%) in Aspen trees (Populus tremuloides) growing in Laramie (WY) using NEON’s (National Ecology Observation Network) Phenology data form. In this study, the data recorded from 2015 through 2018 were analyzed to identify trends in the rate of color change in dry and normal years. Trees that were in an area with a high amount of shade were observed to change leaf color and drop their leaves faster than those in areas that received more sun. This pattern was consistent even in years that experienced winter-like conditions in September. Findings from this multi-year study indicate that future environmental modeling projects must factor in the amount of sunlight received by aspen trees in the growing season into account.

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Predicting leaf traits of temperate broadleaf deciduous trees from hyperspectral reflectance: can a general model be applied across a growing season?

Remote Sensing of Environment ◽

10.1016/j.rse.2021.112767 ◽

2021 ◽

pp. 112767

Author(s):

Litong Chen ◽

Yi Zhang ◽

Matheus Henrique Nunes ◽

Jaz Stoddart ◽

Sacha Khoury ◽

...

Keyword(s):

General Model ◽

Leaf Traits ◽

Growing Season ◽

Deciduous Trees ◽

Hyperspectral Reflectance

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Motor–manual, mechanical, and herbicide release affect early successional vegetation in northwestern Ontario

The Forestry Chronicle ◽

10.5558/tfc73061-1 ◽

1997 ◽

Vol 73 (1) ◽

pp. 61-68 ◽

Cited By ~ 31

Author(s):

F. Wayne Bell ◽

R. A. Lautenschlager ◽

Robert G. Wagner ◽

Doug G. Pitt ◽

John W. Hawkins ◽

...

Keyword(s):

Univariate Analysis ◽

Growing Season ◽

Deciduous Tree ◽

Deciduous Trees ◽

Percent Cover ◽

Aerial Application ◽

Northwestern Ontario ◽

Pre Treatment ◽

The Individual ◽

Successional Vegetation

Cover and height of vegetation before and one growing season after: 1) motor-manual cutting, 2) mechanical brush cutting (Silvana Selective/Ford Versatile), 3) aerial application of Release® (a.i. triclopyr) herbicide, 4) aerial application of Vision® (a.i. glyphosate) herbicide, and 5) control (no treatment) were quantified. Multivariate analysis permitted the study of vegetation response as a whole, while accounting for correlations that exist among the individual vegetation groups. Univariate analysis were used to study the responses of individual vegetation groups. Although no pre-treatment differences in percent cover were observed (P = 0.128), deciduous tree, shrub, forb, grass, and sedge groups responded differently to the treatments after one growing season (P < 0.018). Post-treatment cover of deciduous tree and shrub groups was lower in herbicide treated plots than in cut plots. Forb, grass and sedge covers varied greatly among treatments. Brush saw and Silvana Selective treatments decreased cover of deciduous trees. Release® decreased cover of deciduous trees and shrubs. Vision® decreased cover of deciduous trees, shrubs and ferns. Cover of all vegetation groups increased on the untreated control. Among the conifer release treatments examined, Vision® reduced woody and herbaceous vegetation most. Key words: clearing saw, conifer release, Falingsnow Ecosystem Project, glyphosate, herbicides, Release®, Silvana Selective, spruce, triclopyr, vegetation management, Vision®.

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Growing season

PsycEXTRA Dataset ◽

10.1037/e541672004-001 ◽

1992 ◽

Author(s):

Nicholas Wellington

Keyword(s):

Growing Season

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Irrigation regime and water consumption of potatoes in the Republic of Bashkortostan, depending on the reclamation condition of lands

Melioration and Water Management ◽

10.32962/0235-2524-2019-6-13-19 ◽

2020 ◽

Vol 0 (6) ◽

pp. 13-19

Author(s):

Guzel Gumerova ◽

Georgiy Gulyuk ◽

Dmitry Kucher ◽

Anatoly Shuravilin ◽

Elena Piven

Keyword(s):

Water Consumption ◽

Weather Conditions ◽

Growing Season ◽

Vegetation Period ◽

Forest Steppe ◽

Total Water ◽

Total Water Consumption ◽

Republic Of Bashkortostan ◽

Irrigated Lands ◽

The Republic

Data of long-term researches (2015–2018) in southern forest-steppe zone of the Republic of Bashkortostan, is justified theoretically and experimentally the mode of irrigation of potatoes on leached chernozems of unsatisfactory, satisfactory and good ameliorative condition of irrigated lands. For the growing periods of potatoes with different heat and moisture supply, the number of watering, the timing of their implementation, irrigation and irrigation norms are established. On lands with unsatisfactory meliorative state the number of irrigation depending on weather conditions of potato vegetation period varied from 0 to 3 (1.5 on average) with average irrigation norm – 990 m3/ha. With satisfactory meliorative state of lands the number of irrigation on average increased from 0 to 4 (2.3 on average) with irrigation norm – 1305 m3/ha. On lands with good meliorative state the number of irrigation was the highest – from 1 to 5 (3 on average) with average irrigation irrigation norm is 1653 m3/ha. It was noted that in the dry periods of potato vegetation the greatest number of watering was carried out (3–5 watering), and in the wet periods (2017) watering was not carried out except for the area with a good reclamation state, where only one irrigation was carried out by the norm of 550 m3/ha. Water consumption of potato was studied in dynamics as a whole during the growing season and the months of the growing season depending on weather conditions of vegetation period and land reclamation condition of irrigated lands, as well as in the control (without irrigation). The lowest total water consumption was in the area without irrigation and averaged 226.8 mm. In irrigated areas, its values increased to 319-353.4 mm. The average daily water consumption varied from 2.12 to 3.3 mm. The highest rates of potato water consumption were observed in June and July, and the lowest – in May and August. In the total water consumption of potatoes on the site without irrigation, the largest share was occupied by atmospheric precipitation and in addition to them the arrival of moisture from the soil. Irrigation water was used in irrigated areas along with precipitation, the share of which was 30.2–46.1 %.

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Dynamics of CO2 emission from chernozems under agricultural use

Agricultural science and practice ◽

10.15407/agrisp4.03.043 ◽

2017 ◽

Vol 4 (3) ◽

pp. 43-49

Author(s):

M. Miroshnychenko ◽

O. Siabruk

Keyword(s):

Carbon Dioxide ◽

Agricultural Practices ◽

Growing Season ◽

Warm Period ◽

Direct Seeding ◽

Soil Tillage ◽

Plant Residues ◽

Hydrothermal Conditions ◽

Organic Mineral ◽

Mineral System

Aim. The comparison of the effect of hydrothermal conditions and various agricultural practices on the emission of CO 2 from chernozems in the Left-Bank Forest-Steppe of Ukraine. Methods. The dynamics of the intensity of carbon dioxide emissions from chernozem calcic (typical chernozem – in Ukrainian classifi cation) was studied during the growing season of 2011–2012. The observations were based on two fi eld experiments with various methods of soil till- age (6–7 years from the beginning of the experiment) and fertilization systems (21–22 years from the beginning of the experiment). Particularly, plowing at 20–22 cm, disking at 10–12 cm, cultivation at 6–8 cm and direct seeding using Great Plains drill were studied among the soil tillage methods. Mineral system (N 45 P 50 K 45 ), organic system (manure 8 t/ha) and combined organic-mineral system (manure 8 t/ha + N 45 P 50 K 45 ) were studied among fertilization systems. The intensity of CO 2 fl ux was determined using the non-stationary respiratory chambers by the alkaline absorption method, with averaging of the results during the day and the frequency of once a month. Results. During the warm period, the emission of carbon dioxide from the soil changes dynamically depending on temperature and humidity. The maximum of emission coincides with the periods of warm summer showers in June-July, the minimum values are characteristic for the late autumn period. The total emission losses of carbon in chernozems over the vegetation period ranged from 480 to 910 kg/ha and varied depending on the methods of tillage ± (4.0–6.0) % and fertilization systems ± (3.8–7.1) %. The changes in the intensity of CO 2 emission from the soil under different methods of soil tillage are associated with hydrothermal regime and the depth of crop residues location. The biggest difference is observed im- mediately after tillage, but in the spring period the differences are only 12–25 %, and after drying of the top layer of soil become even less. Direct seeding technology provides the greatest emission of CO 2 from chernozem, which is fa- cilitated by better water regime and more complete mineralization of plant residues on the soil surface. Annual losses of carbon are the least under disking of soil at 10–12 cm. The changes in the intensity of CO 2 emission from the soil under different fertilization systems are associated with the involvement of the additional organic matter from plant residues and manure to the microbiological decomposition. The greatest emission was observed under the organic- mineral fertilization system, which increased the loss of carbon by 7–8 % in comparison with the mineral system in the unfavorable hydrothermal year and by 11–15 % in the more favorable year. These differences are observed mainly during the fi rst half of the growing season when there is a clear tendency to increase the intensity of soil respiration. Conclusions. The hydrothermal conditions of the warm period of the year are decisive in the formation of the CO 2 emission fl ow from chernozems. Due to the improvement of agricultural practices, emissions might be reduced but not more that by 15 % of natural factor contribution.

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