scholarly journals Short Shoot Growth and Reproduction Response to Light Conditions Vary with Order Branching in the Proximal Part of C. atlantica Crown

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Fatima-Ezzahra Saouab ◽  
Mohammed Bendriss Amraoui
Keyword(s):  
Sun Exposure ◽  
Shoot Elongation ◽  
Proximal Part ◽  
Leaf Life Span ◽  
Short Shoot ◽  
Branch Order ◽  
Individual Branch ◽  
Short Shoots ◽  
The Impact ◽  
Growth And Reproduction

This study compared the effects of shading in individual branch orders 2 and 3 on the needle survival, growth, and reproduction of five categories of short shoots of the proximal part of wild Atlas cedar (Cedrus atlantica (Endl.) G. Manetti ex Carrière). The sun exposure did not affect the number of short shoots in the two branch orders, whereas light compared to shade only stimulates the unbranched short shoot elongation of the branch order 3. The impact of shade exposure compared to sun on the loss of needles depends on the order of branching; it is weak to order 2 and increases to higher order. This effect in the branch order 3 is achieved by a significant decrease of the fallen leaf number in the unbranched short shoot SSnr and the short shoot SS/T worn by Twigs while in the branch order 2 only short shoot SS (nr + r) loses significantly few needles. In terms of short shoot extension and needle loss, the SS/T of the branch order 3 behaves in the same way as the SS (nr + r) of the branch order 2. The shadow compared to sunlit only decreases significantly the production of pollen strobili of the branch order 2. Close relationships between short shoot extension, leaf life span, and pollen strobili production of axillary products in the proximal part of C. atlantica crown were found.

Shoot-length frequencies in black birch (Betula lenta)

1991 ◽  
Vol 21 (10) ◽  
pp. 1475-1480 ◽  
Author(s):  
Brayton F. Wilson
Keyword(s):  
Main Axis ◽  
Shoot Length ◽  
Short Shoot ◽  
Lateral Shoot ◽  
Shoot Production ◽  
Shoot Number ◽  
Individual Branch ◽  
Axis Elongation ◽  
Long Shoots ◽  
Short Shoots

Lengths of all parent and current shoots were measured on three 8- to 10-year-old black birch (Betulalenta L.) trees with branches <8 years old. Older branches had more short shoots (<1 cm long) and shorter long shoots (>2 cm long) than younger branches. Parent long shoots produced three to nine basal short shoots. Observations on short-shoot production were consistent with the hypothesis that only buds with adequate nutrition formed long shoots. Three growth rules were developed for a model that simulated individual branch growth: (i) a regression predicting lateral shoot number from each parent shoot length; (ii) probabilities for the number of short shoots produced by a parent shoot based on the total number of current shoots produced per parent shoot; (iii) a regression predicting current shoot length from parent shoot length, current shoot position (longest to shortest), branch age, and main-axis elongation in the current and previous year. Simulations of 81 branches using these rules predicted shoot numbers and total shoot lengths close to those of the actual branches (R2 = 0.73–0.84).

Bud development in Larix occidentalis. II. Cone differentiation and early development

1979 ◽  
Vol 57 (14) ◽  
pp. 1557-1572 ◽  
Author(s):  
John N. Owens ◽  
Marje Molder
Keyword(s):  
Shoot Elongation ◽  
Larix Occidentalis ◽  
Short Shoot ◽  
Bud Development ◽  
Seed Cone ◽  
Long Shoots ◽  
Short Shoots ◽  
Old Trees ◽  
Mother Cells ◽  
Pollen Cone

The time and method of cone-bud differentiation and the phenology of cone-bud development were studied in 10- to 20-year-old trees growing outside their natural range and three 50-year-old trees growing within their natural range.Both pollen-cone and seed-cone buds of western larch (Larix occidentalis Nutt.) normally differentiated on short shoots that were at least 1 year old. Pollen-cone buds were commonly on proximal nonvigorous, often pendant vegetative long shoots in lower regions of the crown, whereas seed-cone buds were usually found on distal short shoots on vigorous but less pendant vegetative long shoots in upper regions of the crown.All potential cone buds were indistinguishable from potential vegetative short shoot buds during bud-scale initiation. In early June, when vegetative short shoots had begun to initiate leaves, cone-bud apices entered a period of differentiation during which time the mitotic frequency of the apices greatly increased followed by a marked increase in apical size. During differentiation, pollen-cone apices did not initiate any basal foliar organs and a short stalk resulted at the base of the cone, whereas seed-cone apices initiated a few basal foliar primordia before bract initiation began. Microsporophyll initiation began during the last half of June and initiation occurred rapidly until the end of July. Micros porangial development occurred from August to late October when fully developed pollen-cone buds became dormant. Pollen mother cells began meiosis before dormancy and overwintered at the diffuse stage. Bract initiation began about the end of June, was rapid until mid-August, then continued more slowly until seed-cone buds became dormant in late October. Ovuliferous scales were initiated acropetally from mid-August until dormancy. Cone-bud differentiation occurred at about the end of the period of vegetative lateral long shoot elongation at all locations.

scholarly journals Analysis of Office Rooms Energy Consumption Data in Respect to Meteorological and Direct Sun Exposure Conditions

Energies ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 7590
Author(s):  
Adam Kula ◽  
Albert Smalcerz ◽  
Maciej Sajkowski ◽  
Zygmunt Kamiński
Keyword(s):  
Energy Consumption ◽  
Public Service ◽  
Residential Buildings ◽  
Sun Exposure ◽  
Building Energy ◽  
The West ◽  
Building Energy Management ◽  
Consumption Data ◽  
Office Rooms ◽  
The Impact

There are many papers concerning the consumption of energy in different buildings. Most describe residential buildings, with only a few about office- or public service buildings. Few articles showcase the use of energy consumption in specific rooms of a building, directed in different geographical directions. On the other hand, many publications present methods, such as machine learning or AI, for building energy management and prediction of its consumption. These methods have limitations and represent a certain level of uncertainty. In order to compare energy consumption of different rooms, the measurements of particular building-room parameters were collected and analyzed. The obtained results showcase the effect of room location, regarding geographical directions, for the consumption of energy for heating. For south-exposed rooms, due to sun radiation, it is possible to switch heating off completely, and even overheating of 3 °C above the 22 °C temperature set point occurs. The impact of the sun radiation for rooms with a window directed east or west reached about 1 °C and lasts for a few hours before noon for the east, and until late afternoon for the west.

scholarly journals College Students’ Perceptions of Worry and Parent Beliefs: Associations with Behaviors to Prevent Sun Exposure

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Robert A. Yockey ◽  
Laura A. Nabors ◽  
Oladunni Oluwoye ◽  
Kristen Welker ◽  
Angelica M. Hardee
Keyword(s):  
College Students ◽  
Protective Clothing ◽  
Sun Exposure ◽  
Sun Protection ◽  
Parental Beliefs ◽  
Parent Beliefs ◽  
Prevention Messages ◽  
Midwestern University ◽  
History Of ◽  
The Impact

More research is needed to understand how attitudes impact behaviors that afford sun protection. The current study examined the impact of students’ perceptions of parental beliefs about sun exposure and its influence on their practiced sun protection behaviors and worry about sun exposure. Participants were college students (N=462) at a large Midwestern university. They completed a survey to examine their perceptions of risks and messages about sun exposure and sun exposure behaviors. Results indicated that gender and students’ perceptions of parental beliefs about sun exposure were related to sun protection behaviors and their own worry over sun exposure. Specifically, males showed lower levels of sun protection behaviors, with the exception of wearing a hat with a brim, and lower levels of worry about sun exposure compared to females. Roughly a third of our sample had a family history of skin cancer, and this variable was related to worry about sun exposure and parental beliefs. Prevention messages and interventions to reduce sun risk for college students should address risks of sun exposure as well as educating young adults about the importance of wearing sunscreen, protective clothing, and hats to improve sun protection.

Growth and reproductive biology of Joffrea speirsii gen. et sp. nov., a Cercidiphyllum-like plant from the Late Paleocene of Alberta, Canada

1985 ◽  
Vol 63 (2) ◽  
pp. 340-364 ◽  
Author(s):  
Peter R. Crane ◽  
Ruth A. Stockey
Keyword(s):  
Upper Cretaceous ◽  
Constant Field ◽  
Short Shoot ◽  
Early Tertiary ◽  
Late Paleocene ◽  
Large Numbers ◽  
Close Relationship ◽  
Field Association ◽  
Short Shoots ◽  
Floodplain Habitats

Six kinds of angiosperm compression fossils are described from the Paskapoo Formation (Late Paleocene) at Joffre Bridge near Red Deer, Alta. Pistillate inflorescences with attached carpels, folliculate infructescences, seeds, seedlings, leaves, and shoots arc all assigned to Joffrea speirsii gen. et sp. nov. Crane and Stockey. Evidence for treating the different organs under a single binomial includes attachment of inflorescences and leaf petioles to long and short shoot systems, morphological intermediates between carpels and follicles, follicles preserved expelling seeds, seeds preserved during germination, stages in seedling development, similarity between seedling and adult foliage, and constant field association. Joffrea is similar in many respects to the widespread Upper Cretaceous and early Tertiary fossil Nyssidium arcticum (Heer) Iljinskaja. Comparison of Joffrea to the extant genera Cercidiphyllum Siebold et Zuccarini, Trochodendron Siebold et Zuccarini, and Tetracentron Oliver indicates a close relationship to Cercidiphyllum; and Joffrea is interpreted as an extinct representative of the family Cercidiphyllaceae. The fossil material clarifies morphological interpretations of the pistillate reproductive structures in extant Cercidiphyllum. The probable staminate inflorescences of Joffrea, are also similar to extant Cercidiphyllum. They are budlike and composed of 10–20 bracts, some of which have stamens in their axils. Pollen has not been recovered from the anthers. Pistillate inflorescences developed from axillary buds on the short shoots and were probably wind-pollinated. The production of numerous small winged seeds, epigeal germination, and the preservation of large numbers of in situ seedlings suggest that Joffrea speirsii and similar extinct Upper Cretaceous and early Tertiary species may have been "weedy" plants capable of rapidly colonizing open floodplain habitats.

Leaf area development on different shoot types in a young aspen stand and its effect upon production

1970 ◽  
Vol 48 (10) ◽  
pp. 1801-1804 ◽  
Author(s):  
D. F. W. Pollard
Keyword(s):  
Leaf Area ◽  
Total Production ◽  
Short Shoot ◽  
Area Index ◽  
Young Leaves ◽  
Long Shoots ◽  
Short Shoots ◽  
Area Development ◽  
Leaf Area Development ◽  
Photosynthetic Efficiencies

Different shoot types in aspen crowns carried leaves of different ages; leaders continued to produce leaves until early August and always carried some young leaves, whereas short shoots completed development by mid-June. Development of foliage on long shoots was intermediate between that on leaders and short shoots. Leaf area index of the 6-year-old stand reached a maximum of 2.4, of which 2.1 was contributed by short-shoot foliage. The rest was formed by leaders and long shoots. Young leaves on leaders and long shoots were not sufficient to influence total production in the stand appreciably, even though young aspen leaves may have high photosynthetic efficiencies. These young leaves could, however, influence height growth and lateral development of the canopy.

Study on the Impact of Water Environmental Factors on Dominant Species of Phytoplankton around the Power Plant in Xiangshan Bay

2012 ◽  
Vol 610-613 ◽  
pp. 3371-3374 ◽  
Author(s):  
Hong Yang ◽  
Ying Zhao ◽  
Hui Rong Zhang ◽  
Gui Xiang Dai ◽  
Jun Ding ◽  
...  
Keyword(s):  
Power Plant ◽  
Environmental Factors ◽  
Statistical Model ◽  
Water Temperature ◽  
Temperature Increase ◽  
Dominant Species ◽  
Thermal Discharge ◽  
Xiangshan Bay ◽  
The Impact ◽  
Growth And Reproduction

The SPSS19.0 software was used to analyse the data of enclosure experiments last for 7 days in summer of 2011. Water temperature increase as a factor to establish the statistical model, and the response relation of thermal discharge warming and Coscinodiscus Jonesianus biomass was analyzed quantitatively. The results showed that, it would promote Coscinodiscus Jonesianus growth and reproduction with the water warming at 0.2°C to 0.79°C , which would be restrained at the water warming at 0.8°C to 2.0°C. When the water temperature increase 0.1°C, 0.4°C and 0.7°Cwill respectively result in Coscinodiscus Jonesianus biomass grow 216.12%, 72.87% and 15.05%. While the water temperature increase 1.0°C, 1.5°C and 2.0°C will respectively result in Coscinodiscus Jonesianus biomass reduce 6.38%, 17.95% and 26.17%.

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