Final answer:
Community structure in ecology refers to the arrangement of species within an ecosystem, with species richness and species interactions being two important descriptors. It includes foundational and keystone species. Knowledge of community structure helps in effective ecosystem management and understanding its dynamics over time.
Step-by-step explanation:
Community structure refers to the composition and arrangement of species within an ecosystem. Two important descriptors of community structure are species richness and the interactions between different populations, such as predation, competition, and various types of symbiotic relationships like mutualism or parasitism. Species richness is essentially the number of different species present in a particular area, and it is a key measure of biodiversity. Interactions among species impact the overall structure and functionality of a community, influencing the role of certain species, known as keystone species, which can have a disproportionate effect on the structure and health of the ecosystem.
Understanding community structure is instrumental for ecologists in managing ecosystems effectively and minimizing the human impact on various ecological communities. This includes knowledge about foundation species, which form the base of a community, and keystone species, which have a significant impact on the community structure. Changes to these can lead to shifts in the community dynamics, the way a community changes and evolves over time, often after disturbances or environmental changes.