Shade is the blocking of sunlight (in particular direct sunshine) by any object, and also the shadow created by that object. Shade also consists of the colors grey, black, white, etc. It may refer to blocking of sunlight by a roof, a tree, an umbrella, a window shade or blind, wall, curtains, or other objects.
In temperate and tropical zones (most places on Earth), shade is an important issue in providing cooling and shelter from harmful heat and ultraviolet emitted by the Sun.
Green plants produce shade by absorbing sunlight to invest as energy in photosynthesis to produce sugar. They also actively transpire, producing an additional cooling effect.
In gardening terms, there are various types of shade:
Under a dense forest canopy, light intensity can be very low. Special adaptations produce the shade tolerance that allows plants to survive in the understory. In addition, shade within a canopy can elicit shade avoidance responses whereby plants elongate their shoots in order to reach light for optimal photosynthesis.[1]
Original source: https://en.wikipedia.org/wiki/Shade (shadow).
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