Ecological Resilience is the capacity of an ecosystem, including cities, to withstand external pressures and return, over time, to its pre-disturbance state. In simpler words, it is the system’s ability to ‘bounce back to its original character’. When viewed over an appropriate time span, a resilient ecosystem is able to maintain its ‘identity’ in terms of taxonomic composition, structure, ecological functions, and process rates. To simplify yet again, a resilient ecosystem can recover its lost plants and animals, and their abode.
And also ensure that the services that are provided by the plants and animals to the ecosystem is revived and continued.
Resilience is hence the key to the management of complex systems of people and nature. In recent years, resilience has become the pivotal concept to identify management actions that aim to alleviate local stressors in an effort to increase ecosystem resilience. The most critical point however is that by their very nature and composition, urban areas, notably mega cities such as Chennai are designated as ‘uncertain environments’ and resilience planning for such environments is a challenge for which easy answers are not available.
Surprisingly, resilience as a concept is not certainly new. It was as early as 1973 that the term was introduced to the world by CS Holling. More recently, Gunderson in 2000 expanded its connotation to define resilience as the ability of a system to absorb impacts before a threshold is reached where the system changes into a different state. Yes, he was referring to the tipping point. An apt description one would say for the city of Chennai which has evolved from a very stable coastal city to that which is under duress almost on a regular basis.
It is to be noted that even stable natural systems such as coral reefs, forests etc undergo transition, but the moot point is that their change does not impact human lives immediately. On the other hand, cities which are designated uncertain environments undergo rapid transition with serious and varying repercussions to human lives and living. Worse still, there is hardly any recovery time for corrective action. Ecologists would detail three main properties of resilience, which are a) the amount of change the system can undergo and still remain within the same domain b) the degree to which the system is capable of self-organization; and c)the degree to which the system can build the capacity to learn and adapt. Adaptive capacity reflects the learning aspect of system’s behaviour in response to disturbance. It is the ability of the city to cope with situations without losing options for the future. It is the key to evolve desirable pathways for development, specifically in uncertain environments.
The call is therefore for the Chennai to recognise that as a mega city, it is an ‘uncertain environment’, whose resilience to natural events and hazards is precarious. It is a city that has changed, and will continue to change. The pace and path of change is what would determine its ability to bounce back. Chennai needs to cope with, adapt to and shape change.
— The writer is Managing Trustee - Care Earth Trust