Dynamics of non-structural carbohydrates in two Ficus species after transfer to deep shade

By late April, the snow is gone from the beaver meadow. The promises of March are starting to be fulfilled: insects are on the wing, some of the willows have furry catkins along their branches, and fish jump from the quiet waters of the beaver ponds. I can no longer easily get around the beaver meadows on foot unless I wear chest waders. The sound of the beaver meadow in March was primarily wind. By April, the sound is primarily moving water. The water gurgles, shushes, and whispers. In another month it will roar with the melting snows. Another three miles up the creek valley and 1,500 feet higher, one of my long-term study sites still lies under 6 feet of snow, but in the meadow I see only one patch of tenacious snow-ice in the deep shade beneath a spruce along the northern edge of the meadow. I know that snow will still fall here during late spring storms, but it will melt quickly. March felt on the cusp, as if it could as easily tip toward winter or spring. Late April is definitely spring headed toward summer. The beaver meadow remains a riverscape more brown and tan than green. The willows are still leafless, although some of the branch tips are turning pale yellow-green and others seem to be taking on a more vivid orange hue. I can see the leaf buds starting to swell. The grass has just begun to grow in dark green tips steadily forcing their way through the thick mat of last year’s dead stems. Clusters of new leaves on low-growing wintergreen are the only other sign of green outside of the channels. Some of the smaller side channels are thick with emerald green algae undulating slowly in the current. A stonefly lands on my hand. Its slender, dark gray body seems surprisingly delicate for a creature that has hatched into the vagaries of April air, with its potential for blasting winds and sudden snow squalls.

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EFFECTS OF EXPOSURE TO DIRECT SUNLIGHT UPON THE DEVELOPMENT OF LEAF STRUCTURE OF TWO DECIDUOUS SHRUB SPECIES

Canadian Journal of Botany ◽

10.1139/b53-042 ◽

1953 ◽

Vol 31 (5) ◽

pp. 537-541 ◽

Cited By ~ 10

Author(s):

R. G. H. Cormack ◽

Anne L. Gorham

Keyword(s):

Ground Cover ◽

Anatomical Study ◽

Shrub Species ◽

Structural Modifications ◽

Previous Season ◽

Sun And Shade Leaves ◽

Deep Shade ◽

Sun And Shade ◽

Palisade Cells ◽

Shade Leaves

The present anatomical study of sun and shade leaves of two shrub species Menziesia glabella and Lonicera glaucescens is an outgrowth of interest in the response of ground cover plants to increased sunlight as the result of logging operations. Leaves of both shrub species developed on plants fully exposed to the sun are smaller, thicker, more compact, with longer palisade cells, less spongy mesophyll, and thicker cuticle than comparable leaves from plants growing normally in deep shade. Evidence is given for the views that (1) differences in leaf expression are not predetermined by the environment of the bud during its formation the previous season, and (2) structural modifications that result when typical shade buds are suddenly exposed to full sunlight are merely an indication of the plasticity of leaves to light.

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Invasion by Pittosporum undulatum of the Forests of Central Victoria. III. Effects of Temperature and Light on Growth and Drought Resistance

Australian Journal of Botany ◽

10.1071/bt9820347 ◽

1982 ◽

Vol 30 (3) ◽

pp. 347 ◽

Cited By ~ 10

Author(s):

RM Gleadow ◽

KS Rowan

Keyword(s):

Leaf Area ◽

Photon Flux ◽

First Year ◽

Low Light ◽

Relative Growth ◽

Relative Growth Rates ◽

Drought Tolerant ◽

Deep Shade ◽

Net Assimilation ◽

Shade Plants

The clumping of invading seedlings of Pittosporum undulatum Vent. around the butts of established trees is due partly to the site-dependent survival of seedlings. particularly during summer. P. undulatum seedlings were very drought-tolerant when grown at moderately low temperatures (21.4°C day/17.8°C night compared with 27.4°C day/23.9°C night) and in deep shade. Plants droughted at 5°C higher temperatures and higher photon flux densities stopped transpiring and wilted 10-13 days earlier than those droughted under cooler, densely shaded conditions. Well watered seedlings had higher relative growth rates and net assimilation rates when grown under higher temperatures and photon flux densities. Control seedlings were more leafy when grown under low light. as reflected by the specific leaf area, leaf area ratio and root/shoot ratios. The adverse effects of higher photon flux densities and temperatures on the drought tolerance of P. undulatum seedlings support the hypothesis that survlval of invading seedlings in their first year is dependent on the microclimate.

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SEED SIZE, NITROGEN SUPPLY, AND GROWTH RATE AFFECT TREE SEEDLING SURVIVAL IN DEEP SHADE

Ecology ◽

10.1890/0012-9658(2000)081[1887:ssnsag]2.0.co;2 ◽

2000 ◽

Vol 81 (7) ◽

pp. 1887-1901 ◽

Cited By ~ 169

Author(s):

Michael B. Walters ◽

Peter B. Reich

Keyword(s):

Growth Rate ◽

Seed Size ◽

Seedling Survival ◽

Nitrogen Supply ◽

Tree Seedling ◽

Deep Shade

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“If a Tree Falls …” : Posthuman Testimony in C. D. Wright’s Casting Deep Shade

a/b Auto/Biography Studies ◽

10.1080/08989575.2020.1720183 ◽

2020 ◽

Vol 35 (1) ◽

pp. 123-143

Author(s):

Eamonn Connor

Keyword(s):

Deep Shade ◽

Tree Falls

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Photosynthetic Response to Light and Nutrients in Sun-Tolerant and Shade-Tolerant Rainforest Trees. I. Growth, Leaf Anatomy and Nutrient Content.

Functional Plant Biology ◽

10.1071/pp9920001 ◽

1992 ◽

Vol 19 (1) ◽

pp. 1 ◽

Cited By ~ 45

Author(s):

WA Thompson ◽

PE Kriedemann ◽

IE Craig

Keyword(s):

Leaf Anatomy ◽

Forest Floor ◽

Interactive Effect ◽

Nutrient Content ◽

Starch Accumulation ◽

Strong Light ◽

Light Regimes ◽

Deep Shade ◽

Successional Species ◽

Sun And Shade

Seedling trees of Argyrodendron sp., A. trifoliolaturn, Flindersia brayleyana and Toona australis were grown for c. 180 days under one of three light regimes with either of two nutrient levels (6 treatments in all). Light regimes spanned the range of environmental conditions which these species would normally experience in northern Queensland rainforest: deep shade (1.3 mol quanta m-2 day-1, equivalent to forest floor), moderate light (5.6 mol quanta m-2 day-1, comparable to midcanopy), and strong light (23 mol quanta m-2 day-1, matching daily irradiance of exposed crowns). Long-term shade tolerance in Argyrodendron sp. and A. trifoliolaturn was associated with limited responses in growth and leaf anatomy to low light and nutrients. Starch accumulation in leaves under all treatments, and especially low nutrients, implied that supply of photoassimilate exceeded demand. Such a conservative carbon economy, plus the accumulation of stem P reserves, even in a weak light environment, is consistent with a protracted existence as part of a forest floor community. By contrast, shade-intolerant Toona is an early successional species and lacks such adaptive features. Instead, light and nutrients had a strong interactive effect on growth. Flindersia, with a broad tolerance to sun and shade, was intermediate in growth response and leaf adjustment, which is consistent with its success across a wide size range of forest gaps.

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