Effects of Light Intensity and Regeneration Mode on Stem Form and Growth of Cunninghamia lanceolata Saplings

Abstract Background: An understanding of the light requirement of tree species has paramount importance in management of mixed species forests. Here, we examined changes in leaf morphological traits, non-structural carbohydrate contents and C:N:P stoichiometry in Cunninghamia lanceolata and Schima superba seedlings that were grown under five light intensity levels (5%, 15%, 40%, 60%, and 100% sunlight) in a shade house. Results: Mean leaf area was significantly larger under 40% light intensity for C. lanceolata while maximum mean leaf area was observed under 15% light intensity for S. superba seedlings, whereas leaf mass per area decreased consistently with decreasing light intensity in S. superba; Non-structural carbohydrate content was higher for S. superba than C. lanceolata when seedlings were exposed to 100%, 15% and 5% light intensity; Leaf C:N ratio decreased while N:P ratio increased with decreasing light intensity; leaf C:P ratio was highest in 40% light intensity for C. lanceolata and in 60% light intensity for S. superba. Conclusion: S. superba is better adapted to low light intensity than C. lanceolata through enlarged leaf area and increased carbohydrate reserves that allow the plant to better maintain C balance. From mixed species planting viewpoint, it would be advisable to plant S. superba later once the canopy of C. lanceolata is well developed but allowing enough sunlight (up to 15%-60%).

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Analysis of various crown variables on stem form for Cunninghamia lanceolata based on ANN and taper function

Forest Ecology and Management ◽

10.1016/j.foreco.2021.119973 ◽

2022 ◽

Vol 507 ◽

pp. 119973

Author(s):

Ruiting Liang ◽

Yujun Sun ◽

Lai Zhou ◽

Yifu Wang ◽

Siyu Qiu ◽

...

Keyword(s):

Cunninghamia Lanceolata ◽

Stem Form ◽

Taper Function

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Fine structure of the retina of the giant scallop, Placopecten magellanicus

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111677 ◽

1984 ◽

Vol 42 ◽

pp. 312-313

Author(s):

C.V.L. Powell

Keyword(s):

Fine Structure ◽

Electron Microscope ◽

Light Intensity ◽

Scanning Electron Microscope ◽

Eye Development ◽

Preliminary Observation ◽

Columnar Epithelium ◽

Placopecten Magellanicus ◽

Environmental Light ◽

Scanning Electron

The overall fine structure of the eye in Placopecten is similar to that of other scallops. The optic tentacle consists of an outer columnar epithelium which is modified into a pigmented iris and a cornea (Fig. 1). This capsule encloses the cellular lens, retina, reflecting argentea and the pigmented tapetum. The retina is divided into two parts (Fig. 2). The distal retina functions in the detection of movement and the proximal retina monitors environmental light intensity. The purpose of the present study is to describe the ultrastructure of the retina as a preliminary observation on eye development. This is also the first known presentation of scanning electron microscope studies of the eye of the scallop.

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Effect of light intensity on the ultrastructure of the filamentous cyanobacterium, Anabaena variabilis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100103565 ◽

1988 ◽

Vol 46 ◽

pp. 300-301

Author(s):

C. S. Bricker ◽

S. R. Barnum ◽

B. Huang ◽

J. G. Jaworskl

Keyword(s):

Fatty Acid ◽

Light Intensity ◽

Acid Content ◽

Fatty Acid Content ◽

Anabaena Variabilis ◽

Chloroplast Envelope ◽

Major Constituent ◽

Filamentous Cyanobacterium ◽

Photosynthetic Membrane ◽

Effect Of Light

Cyanobacteria are Gram negative prokaryotes that are capable of oxygenic photosynthesis. Although there are many similarities between eukaryotes and cyanobacteria in electron transfer and phosphorylation during photosynthesis, there are two features of the photosynthetic apparatus in cyanobacteria which distinguishes them from plants. Cyanobacteria contain phycobiliproteins organized in phycobilisomes on the surface of photosynthetic membrane. Another difference is in the organization of the photosynthetic membranes. Instead of stacked thylakolds within a chloroplast envelope membrane, as seen In eukaryotes, IntracytopIasmlc membranes generally are arranged in three to six concentric layers. Environmental factors such as temperature, nutrition and light fluency can significantly affect the physiology and morphology of cells. The effect of light Intensity shifts on the ultrastructure of Internal membrane in Anabaena variabilis grown under controlled environmental conditions was examined. Since a major constituent of cyanobacterial thylakolds are lipids, the fatty acid content also was measured and correlated with uItrastructural changes. The regulation of fatty acid synthesis in cyanobacteria ultimately can be studied if the fatty acid content can be manipulated.

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Inter-Method Reliability of Pulse Volume Related Measures Derived Using Finger-Photoplethysmography

Journal of Psychophysiology ◽

10.1027/0269-8803/a000197 ◽

2018 ◽

Vol 32 (4) ◽

pp. 182-190 ◽

Cited By ~ 4

Author(s):

Kenta Matsumura ◽

Koichi Shimizu ◽

Peter Rolfe ◽

Masanori Kakimoto ◽

Takehiro Yamakoshi

Keyword(s):

Light Intensity ◽

Adverse Effects ◽

Light Source ◽

Direct Current ◽

Resting State ◽

Current Component ◽

Psychophysiological Measures ◽

Pulse Volume ◽

Optical Paths ◽

Sensor Positions

Abstract. Pulse volume (PV) and its related measures, such as modified normalized pulse volume (mNPV), direct-current component (DC), and pulse rate (PR), derived from the finger-photoplethysmogram (FPPG), are useful psychophysiological measures. Although considerable uncertainties exist in finger-photoplethysmography, little is known about the extent of the adverse effects on the measures. In this study, we therefore examined the inter-method reliability of each index across sensor positions and light intensities, which are major disturbance factors of FPPG. From the tips of the index fingers of 12 participants in a resting state, three simultaneous FPPGs having overlapping optical paths were recorded, with their light intensity being changed in three steps. The analysis revealed that the minimum values of three coefficients of Cronbach’s α for ln PV, ln mNPV, ln DC, and PR across positions were .948, .850, .922, and 1.000, respectively, and that those across intensities were .774, .985, .485, and .998, respectively. These findings suggest that ln mNPV and PR can be used for psychophysiological studies irrespective of minor differences in sensor attachment positions and light source intensity, whereas and ln DC can also be used for such studies but under the condition of light intensity being fixed.

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