Why is there an alternation of natural zones?

Natural zones on the earth’s surface alternate depending on the amount of heat coming from the Sun and moisture carried by the prevailing winds. Because of the angle at which the earth’s axis is tilted to the plane of the ecliptic, heat is unevenly distributed over the vast earth’s surface. Most of the solar energy falls on the hot belt between the tropics, here the rays of the Sun come almost vertically and warm the surface well. Further to temperate latitudes, and even more strongly to the poles, the angle of arrival of rays from the luminary decreases and less and less heat is supplied. This phenomenon is called latitudinal zoning. Altitude zoning takes place in the mountains at any latitude.