INDIAN GEOGRAPHY

Detailed explanation-1: -When the temperatures in the autumn season begin to drop, the air becomes colder. During this season, the amount of sunshine falls and the production of the chlorophyll pigment in the leaves decreases until it completely stops.

Detailed explanation-2: -In temperate regions, cold winters pose a risk to the leaves of broadleaf trees and other perennials, and so these plants drop their leaves in a controlled fashion to reduce injuries and conserve energy. This event is usually triggered by the declining day length and falling temperatures of autumn.

Detailed explanation-3: -In the fall, the leaves of deciduous trees change color, fall off and die.

Detailed explanation-4: -In spring and summer chlorophyll is the pigment that gives leaves their green color. At the end of summer, the decreased daylight and cooler temperatures, cause chlorophyll to break down, which expose the carotenoid (yellow, orange, and brown) and anthocyanin (red, purple, and crimson) pigments.