Answer:
in 1988, a forest fire destroyed much of yellowstone park.This photo, taken 17 years later,show that the forest is gradually growing back, small grasses first grew here and are now being replaced by small trees and shrubs, this is an example of the later stages of secondary succession.
The early stages of succession after a forest fire are shown in these pictures. taken four years after the fire. they show the charred remains of the original forest as well as the small grasses and shrubs that are beginning to throw in the back area.
During a volcanic eruption,molten lava flows over the ground and into the water. after the eruption is over the lava cools and hardens into bare rock.
lichen spores carried on the wind settle on the rock and creat soil. linchens add nutrients to the soil as they die and decay.
Ecosystems are "dynamic". this means that the ecosystem change
over time.
during the ice ages , glaciers once covered areas that are tropical rainforests today. both natural forces and human actions cause ecosystem to change
if there is a big ecosystem change caused by natrual forces or human actions , the plants and animals that live there might be destroyed. or they may be foreced to leave.
over time a new community will develop and then that community may be replaced by another.
primary succession is the type of eological succession that happens on new lands, lands where life has not yet been existed. primary succession can take place after lava flow cools and hardens into new land or glacier recedes exposing new land.
secondary succession is the type of succession happens after something destroys the habitat, such as a flood or other natrual disaster. abandoning a field that was once used for agriculture can also lead secondary successionn
