Final answer:
Species richness in a community initially increases during ecological succession due to colonization by pioneer species, then plateaus as space and resources become limited, and may decrease towards a climax community due to competition and adaptation to local conditions.
Step-by-step explanation:
Understanding Ecological Succession
During ecological succession, a community undergoes a series of changes following a disturbance or the creation of new land. Species richness initially increases because pioneer species colonize the area, taking advantage of the lack of competition and abundant resources. As the community matures through succession, more species are added, increasing biodiversity and complexity. However, this increase in species richness tends to plateau as the habitat space and resources become more limited, and competition intensifies. Eventually, a stable climax community is formed that is well-adapted to the local conditions. Over time, this climax community might change if another disturbance occurs or if environmental conditions shift, leading to a decrease in species richness as some species outcompete others or as species become extinct.
Climax communities reflect the regional climate and geology and can be a tropical rainforest, coniferous forest, or other stable ecosystems depending on the location. Nevertheless, the concept of climax communities has evolved, and ecologists now understand that ecosystems are dynamic and subject to ongoing changes and disturbances. Therefore, the idea of a permanent climax community is no longer widely accepted.