The oldest stage of succession shown in the figure is the forest.
Succession is the gradual process of ecological change that occurs in a community over time. It typically begins with bare rock or soil, and then progresses through a series of stages until a climax community is reached.
The climax community is the most stable and mature community that can exist in that particular environment.
In the figure, the forest is the most complex and mature stage of succession. It has a high diversity of plant and animal life, and the plants are tall and well-established.
The other stages of succession, such as the bare sand and the grassland, are less complex and have fewer species.
Here is a more detailed explanation of the stages of succession shown in the figure:
Bare sand: This is the starting point for succession. The bare sand is a harsh environment with little or no organic matter. Only a few specialized plants, such as lichens and mosses, can survive in this environment.
Grassland: As the lichens and mosses break down the rock and create soil, grasses and other herbaceous plants are able to colonize the area. The grassland is more stable than the bare sand, but it is still a relatively simple ecosystem.
Shrubland: As the soil continues to develop, shrubs and small trees are able to grow. The shrubland is a more complex ecosystem than the grassland, and it provides habitat for a wider variety of species.
Forest: The forest is the climax community of this succession. It is the most stable and mature stage of succession, and it has the highest diversity of plant and animal life.
The figure shows a primary succession, which is a succession that starts on bare rock or soil.
There is also a type of succession called secondary succession, which starts on land that has already been disturbed, such as by a fire or a clear-cut.
Secondary succession typically proceeds more quickly than primary succession, because there is already some organic matter in the soil.