An assessment of water yield ecosystem services in Periyar Tiger Reserve, Southern Western Ghats of India

Protected area water yield calculation and mapping are of great importance to the conservation planning and resource management. A water yield model based on InVEST was employed to estimate water yield in Periyar Tiger Reserve, a representative in the Southern Western Ghats, Kerala, India. The analysis included land use/land cover, average annual precipitation and potential evapotranspiration, soil depth at various elevation, and plants available water content. The estimated water yield of PTR was 2.33E+09 m3 y-1 with 67% from Periyar river watershed and 33% from Pamba river watershed. A comparison of water-yielding capacity to the forest ecosystems with different vegetations indicates that there is a decreasing trend from evergreen forest, semi-evergreen forest, to grassland-savanna, moist deciduous forest and plantations. It is estimated 37% of evergreen and 24% of semi-evergreen share the major portion of the total water yield, 63.5% of PTR. This study reveals the significance of ecosystem services of the protected area and the importance to conserve and required efficient management.