Perspectives on resilience

A number of volumes have stressed the practical difficulties in attempting to manage ecosystems. The multiple scales of variables, cross-scale connections, and nonlinear interactions generate complex dynamics. Systems of people and nature go through dynamic phases of development, described in resilience theory through the heuristic model of the adaptive renewal cycle. Relatively long periods with little change alternate with short periods of collapse and reorganization in this cycle. During these periods of renewal, resilience can be enhanced or lost, depending on such factors as diversity, redundancy, and memory in the system.