**Acknowledgements**

during the germination stage of riparian tree species. Some native species which supports avifaunal abundance such as *Ixora bracheata, Syzygium cumini, Syzygium jambose, Diospyros melanoxylon* and *Madhuca latifolia* resembles healthy association to the keystone species *Terminalia arjuna*. Also, it checks the growth of pioneer species in the riparian zone, thereby competition with riparian and semi-evergreen species harbored in riparian zone is avoided. Decline in native species such as *Syzygium cumini, Syzygium jambose, Madhuca sp* along the river bank might lead to the decline of natural source of leaves, twigs, fruit and insects that under‐ pins the aquatic food web (Lovett *et al*., 2007). Hence, canopy species like *T.arjuna* is much inevitable in this region where their absence might cause a major change in the riparian vegetation structure and composition which inturn affects the aquatic ecosystem in the region.

Figure 6. A and B. Seedlings of *Syzygium cumini, Ixora bracheata, Madhuca latifolia* and *Dalbergia latifolia* growing in area under

**Figure 6.** A and B. Seedlings of *Syzygium cumini*, *Ixora bracheata*, *Madhuca latifolia* and *Dalbergia latifolia* growing in

The primary uses of Cauvery river are providing water for irrigation, household consumption, industries and the generation of electricity (Varunprasath and Daniel, 2010). Over 90% of the river water is abstracted for irrigation.

indicating that potential for human disturbance is inevitable along the basin. The watershed regions of the Cauvery river is strongly affected by water stress in recent years (Ferdin, et al., 2010). Besides meeting industrial and agricultural needs, drinking water demands from the two major urban centres namely Bangalore (6th largest city in India) and Mysore with a millions population is increasing at an faster rate. The river being completely dependent on the monsoon for replenishment, the amount of water the Cauvery can provide to the various users varies with the fluctuating strength of the monsoon rainfall (Ferdin, et al., 2010). Providing clean water and improving the chemical quality of waters for both human consumption needs and ecosystem health have become important policy goals in the worldwide. Management of riparian vegetation is one strategy to achieve these goals. *Terminalia arjuna* is one of the key species in the Cauvery river to fulfill the strategy to maintain the river quality healthier. The widespread rootmat of this species protect the waterway from erosion and pollutants entering the river. It acts has a natural wall along the river bank resists soil erosion during flooding thereby avoiding the water loss due to the bank widening. Keeping increasing water scarcity and flood disaster in the lower reaches during monsoon, conservation and management of *Terminalia arjuna* in the upper reaches helps to reduce flood velocities and increase the further flow

; Smakhtin et al., 2006) indicating that potential for human

**11. Social significance of** *Terminalia arjuna* **in Cauvery riverine ecosystem**

The primary uses of Cauvery river are providing water for irrigation, household consumption, industries and the generation of electricity (Varunprasath and Daniel, 2010). Over 90% of the river water is abstracted for irrigation. Population density in Cauvery is perhaps among the

disturbance is inevitable along the basin. The watershed regions of the Cauvery river is strongly affected by water stress in recent years (Ferdin, et al., 2010). Besides meeting industrial and agricultural needs, drinking water demands from the two major urban centres namely Bangalore (6th largest city in India) and Mysore with a millions population is increasing at an faster rate. The river being completely dependent on the monsoon for replenishment, the amount of water the Cauvery can provide to the various users varies with the fluctuating

**Acknowledgement:** We thank University Grant Commission for providing financial assistance, Karnataka State

Forest Department in for extending the permission to carry out the studies and helping in field work.

*1.* Amitha Bachan, KH. 2003. *Riparian Vegetation along the middle and lower zones of the Chalakkudy River, Kerala, India*. Limnological Association of Kerala, Iringalakkuda.

conservation significance. *Journal of Threatened Taxa* 3(6): 1837–1841.

2. Baskaran, N., = Senthilkumar. K and Saravanan, M. 2011. A new site record of the Grizzled Giant Squirrel *Ratufa macroura* (Pennant, 1769) in the Hosur forest division, Eastern Ghats, India and its

; Smakhtin et al., 2006)

**Social significance of** *Terminalia arjuna* **in Cauvery Riverine ecosystem** 

**A B** 

104 Biodiversity - The Dynamic Balance of the Planet

towards lower reaches, thereby maintaining the river water healthier.

Population density in Cauvery is perhaps among the highest in the world (350 people/ km<sup>2</sup>

canopy of *Terminalia arjuna* species.

area under canopy of *Terminalia arjuna* species.

highest in the world (350 people/ km2

References

We thank University Grant Commission for providing financial assistance, Karnataka State Forest Department in for extending the permission to carry out the studies and helping in field work.
