It is season of monsoon 2017! You can’t miss this information as few of our friends never fail to update us by expressing their immense love for rain and raindrops on social media. Some adore it, some detest it (specially those who are they stuck in traffic for hours). Amongst many other discussions revolving around monsoon, one perpetual news which makes its entry almost every year is annual scourge of flood in Assam. This monsoon is no different. The magnitude of damage and destruction seems to be increasing every year. Recently a news article was published in which Kaziranga National Park was severely hit by flood. Around 369 animals have lost their lives. Some of those animals include rhinos, one tiger, elephants, and various species of deer. (“1 Tiger, 2 dozen rhinos, hundreds of deer: Flooded Kazinranga”, 2017)
Experts of the Brahmaputra Board did analyse the situation. They have stated three causes for flood; Inadequate capacity of the Brahmaputra river due to its braided nature which causes flood, congestion of drainage at the outfall of tributaries and last but not the least excessive silt load in the river which happen due to soil erosion or landslides in the hilly catchments (“Assam Flood”, 2017). The annual Assam flood mayhem brings loss in terms of human life, wildlife, infrastructure, crops etc. The effort put-up for development of the state and society get back to square one.
One of the apparent perspective which exists for natural disturbance is that, it creates mayhem. Nonetheless like other side of the coin, disturbance regimes have also been beneficial for ecology. Natural disturbance usually has drastic effect on community but they also assist in increasing environmental heterogeneity and diversity (Pickett et al. 1989). Adding on to the discussion, non-equilibrium model leads to maximum diversity in the ecosystem, whereas in equilibrium model, inferior competitors gets replaced by superior competitors which eventually reduces species richness in an ecosystem (Bronette and Amoros, 1996).
The concept of natural disturbance regimes also exists in the field of ecological restoration. For restoration of an ecosystem efforts are put to reintroduce species as well as to recover ecosystem function. In a wetland restoration, hydrological regimes are important but also difficult to revive. For many years, wetland hydrology has been altered by constructing dam, fillings, drainage, groundwater pumping and others. Middleton (Zedler, 2000) in his book “Wetland Restoration, Flood Pulsing, and Disturbance Dynamics” has emphasized the importance of flood pulses which governs community structure along with ecosystem functioning. However, in today’s time the floodplains are covered by human population. Dams are built to control annual flood so people reside with no damage.
Considering both the perspectives of flood, where it is catastrophic for people but also necessary for ecology has certainly put me in catch 22 situation. How do we plan to restore wetland which is located in an urban space? How can we restore hydrology regime of a wetland which was dependent on annual flood? Is it practical to displace people from flood plains? Are we ready to tackle annual flood by deconstructing dams? These are some difficult but important questions which needs appropriate plan. There is need for restoration ecology, but to sort out these issues prior are of paramount concern in places like urban.
References:
- Kashyap, S.G. (2017, 08, 22. 1 Tiger, 2 dozen rhinos, hundreds of deer: Flooded Kazinranga counts its 369 dead. The Indian Express. Retrieved from http://epaper.indianexpress.com/1328693/Indian-Express/August-22,-2017#page/8
- Kashyap, S.G. (2017,07,14). Assam Floods: Annual scourge, with no sign of solution in over 7 decades. The Indian Express. Retrieved from http://epaper.indianexpress.com/1281281/Indian-Express/July-14,-2017#page/14/2
- Pickett, S. T. A., Kolasa, J., Armesto, J. J., & Collins, S. L. (1989). The ecological concept of disturbance and its expression at various hierarchical levels. Oikos, 129-136.
- Zedler, J. B. (2000). Progress in wetland restoration ecology. Trends in Ecology & Evolution, 15(10), 402-407.
- Bornette, G., & Amoros, C. (1996). Disturbance regimes and vegetation dynamics: role of floods in riverine wetlands. Journal of vegetation Science, 7(5), 615-622.
Centre for Urban Ecology and Sustainability 