For ecological habitats, species and processes, strong resistance to change is often related to high biodiversity and healthy ecosystem function. High biodiversity leads to ecological redundancy, which is when multiple ecological components play a similar role in maintaining the ecosystem. This means that when one component fails, another can compensate, and the system is maintained. Because of the complexity of most ecosystems, it is often not practical to manage redundancy directly, and it is more common to manage biodiversity with the knowledge that this will act to maintain ecological redundancy and therefore resilience.
Resistance can also result from keystone or habitat-forming species that have a high tolerance for disturbances, harsh environmental conditions or diseases. Resistance can be increased through breeding programs that bolster tolerant genotypes, or by maximising genetic diversity to allow adaptation to the widest range of environmental conditions (see Box COA12). Ecological community- and species-level resistance to one pressure can also be increased if other pressures are moderated. For example, temperature tolerance may be higher if an organism is in good health.