Wet, sunny, shady, dry, and mesic. When looking at a cross section of a leaf, how can i tell if a leaf are in these enviornments?
For example if there are big air spaces in the cross section of a leaf, then it must be in a wet enviornment because the air spaces store water. Is that right?
For example if there are big air spaces in the cross section of a leaf, then it must be in a wet enviornment because the air spaces store water. Is that right?
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Leaf area is directly related to having a constant water supply and fairly still air. Only very rich, wet soils support leaves of enormous area. Gunnera magnifica are large wetland plants with leaves over 2 meters in diameter.
Large broad leaves are in sunny/shady,WET, tropical/temperate habitats. Shaded leaves in wet habitats will be even larger than the same species in full sun - as long as water is not limited. Shaded plants have the further benefit of shelter from strong winds to allow larger surface areas.
The more limiting the water the narrower the leaf until xeric habitats have needle like leaves or no leaves on photosynthetic stems like cacti. Pine needles are adapted for a xeric environment; water is unavailable either because it is frozen most of the time or else because it is climatically scarce.
An alternate for the dry is found in a rosette of succulent leaves. The leaves are fleshy and succulent to store volumes of water in the vacuoles that take up 90% of each cell. The leaves have sclerification of the vascular tissues reinforcing the cell walls with lignification. This reinforced structure reduces the possible damage from loss of water as the leaves cannot wilt with lowered turgidity. This fibrous nature lets them survive a wide variation of water content
Plants adapted to wind have lobed simple leaves or compound leaves to avoid shredding the large surface area in mesic soils and moderately broad leaves as on oaks or maples.
Large broad leaves are in sunny/shady,WET, tropical/temperate habitats. Shaded leaves in wet habitats will be even larger than the same species in full sun - as long as water is not limited. Shaded plants have the further benefit of shelter from strong winds to allow larger surface areas.
The more limiting the water the narrower the leaf until xeric habitats have needle like leaves or no leaves on photosynthetic stems like cacti. Pine needles are adapted for a xeric environment; water is unavailable either because it is frozen most of the time or else because it is climatically scarce.
An alternate for the dry is found in a rosette of succulent leaves. The leaves are fleshy and succulent to store volumes of water in the vacuoles that take up 90% of each cell. The leaves have sclerification of the vascular tissues reinforcing the cell walls with lignification. This reinforced structure reduces the possible damage from loss of water as the leaves cannot wilt with lowered turgidity. This fibrous nature lets them survive a wide variation of water content
Plants adapted to wind have lobed simple leaves or compound leaves to avoid shredding the large surface area in mesic soils and moderately broad leaves as on oaks or maples.