Ecosystems dynamics is the study of how ecosystems change over time. Ecosystems are dynamic entities, they change over time due to various endogenous and exogenous factors such as abiotic disturbances like earthquakes or floods. At the same time that they are constantly changing they also have to maintain some form of stability to certain critical parameters, such as the PH level in a soil or temperature which are required for enabling organisms to function. This process whereby organisms or whole ecosystems regulate both change and continuity is called homeostasis and homeostasis is one of the defining features of life. The actual mechanisms through which this is done are called feedback loops. On the macro level of a whole ecology this regulation process is distributed out across many different feedback loops between many different species and geological factors. The counterbalancing process of negative feedback works to stabilize the system into a steady state of development. While positive feedback can work to drive nonlinear exponential growth or decay.