What is meant by 'carrying capacity' in ecological terms?

Carrying capacity in ecological terms refers to the maximum population size of a species that an environment can sustainably support over an extended period. This concept takes into account the availability of resources such as food, water, and habitat, as well as the impact of environmental factors such as predation and disease. When a population exceeds its carrying capacity, it can lead to resource depletion, which may ultimately cause a decline in the population due to starvation, increased competition, or other stresses.

The other options refer to different ecological concepts that do not accurately define carrying capacity. The optimum number of species in a community relates to biodiversity and interactions among species, rather than the limits of population size for a single species. The size at which only herbivores can thrive is a specific scenario that does not encompass the broader definition of carrying capacity. Lastly, the total number of species in an ecosystem refers to species richness and diversity rather than the limitations imposed on a population by its environment.