potassium (K), sodium absorption ratio, Na 2 O, K 2 O, P 2 O 5 , and SiO 2 show the
highest correlation whereas in the second component electrical conductivity,
water-soluble aggregates, bulk density, soil texture, silt, carbon:nitrogen ratio, total
phosphorus (P), total sodium (Na), total calcium (Ca), and Al 2 O 3 have the highest
correlation.
Conclusion
In this study, the impact of forest degradation has been analyzed using stream flow
estimation and water and soil quality analysis. The overall impact of forests on the
hydrological regime of a watershed is twofold. First, comparatively less discharge
can be observed from forest watershed (undisturbed catchment) during the rainy
months, showing the forest control over excess runoff downstream. Annual runoff
from a dense forest was lower than that from a disturbed catchment. Second, forests
induce infiltration, which leads to more uniform flow year round from the
undisturbed forest watershed. Net impacts on water quality depend on prior land
use and crop management, current forest management practices, soil type, local
hydrology, and climate. In general, conversions to forestland have the potential to
reduce erosion and subsequent sedimentation, as well as to reduce levels of
dissolved nutrients and pesticides in surface runoff and groundwater. These
improvements in water quality are a function of the lower amounts of runoff and
leaching as well as lower concentrations of potential pollutants that are expected to
result from the conversion of forestland. Further, PCA has been applied to ascertain
correlation among the parameters, and significant correlation has been observed.
Such studies will incur valuable information to stakeholders and policy makers to
conserve the forest watersheds in a sustainable way through physical exploration.
Acknowledgments The authors express their sincere gratitude to The Ministry of Environment,
Forest and Climate Change, Government of India, for providing a research grant to the National
Afforestation and Eco-Development Board, Regional Center, Jadavpur University for the years
2008–2010. Afterward, the work has been continued until 2018 under the collaboration of School of
Water Resources Engineering, Jadavpur University. The authors are also thankful to the Forest
Environment and Wildlife Management Department, Government of Sikkim for providing data and
their continuous support. The authors are also grateful to Central Water Commission, Government
of India for providing discharge data. Last but not the least, the authors acknowledge the water
quality laboratory and digital library of the School of Water Resources Engineering, Jadavpur
University, for allowing to conduct the water and soil quality tests and to access all the GIS and
statistical software.
References
Ewane BE, Lee HH (2020) Assessing land use/land cover change impacts on the hydrology of
Nyong River Basin, Cameroon. J Mt Sci 17:50–67. https://doi.org/10.1007/s11629-019-5611-8
Frene C, Dörner J, Zuniga F, Cuevas JG, Alfaro FD, Armesto JJ (2019) Eco-hydrological functions
in forested catchments of Southern Chile. Ecosystems. https://doi.org/10.1007/s10021-01900404-7
224
M. B. Roy et al.
highest correlation whereas in the second component electrical conductivity,
water-soluble aggregates, bulk density, soil texture, silt, carbon:nitrogen ratio, total
phosphorus (P), total sodium (Na), total calcium (Ca), and Al 2 O 3 have the highest
correlation.
Conclusion
In this study, the impact of forest degradation has been analyzed using stream flow
estimation and water and soil quality analysis. The overall impact of forests on the
hydrological regime of a watershed is twofold. First, comparatively less discharge
can be observed from forest watershed (undisturbed catchment) during the rainy
months, showing the forest control over excess runoff downstream. Annual runoff
from a dense forest was lower than that from a disturbed catchment. Second, forests
induce infiltration, which leads to more uniform flow year round from the
undisturbed forest watershed. Net impacts on water quality depend on prior land
use and crop management, current forest management practices, soil type, local
hydrology, and climate. In general, conversions to forestland have the potential to
reduce erosion and subsequent sedimentation, as well as to reduce levels of
dissolved nutrients and pesticides in surface runoff and groundwater. These
improvements in water quality are a function of the lower amounts of runoff and
leaching as well as lower concentrations of potential pollutants that are expected to
result from the conversion of forestland. Further, PCA has been applied to ascertain
correlation among the parameters, and significant correlation has been observed.
Such studies will incur valuable information to stakeholders and policy makers to
conserve the forest watersheds in a sustainable way through physical exploration.
Acknowledgments The authors express their sincere gratitude to The Ministry of Environment,
Forest and Climate Change, Government of India, for providing a research grant to the National
Afforestation and Eco-Development Board, Regional Center, Jadavpur University for the years
2008–2010. Afterward, the work has been continued until 2018 under the collaboration of School of
Water Resources Engineering, Jadavpur University. The authors are also thankful to the Forest
Environment and Wildlife Management Department, Government of Sikkim for providing data and
their continuous support. The authors are also grateful to Central Water Commission, Government
of India for providing discharge data. Last but not the least, the authors acknowledge the water
quality laboratory and digital library of the School of Water Resources Engineering, Jadavpur
University, for allowing to conduct the water and soil quality tests and to access all the GIS and
statistical software.
References
Ewane BE, Lee HH (2020) Assessing land use/land cover change impacts on the hydrology of
Nyong River Basin, Cameroon. J Mt Sci 17:50–67. https://doi.org/10.1007/s11629-019-5611-8
Frene C, Dörner J, Zuniga F, Cuevas JG, Alfaro FD, Armesto JJ (2019) Eco-hydrological functions
in forested catchments of Southern Chile. Ecosystems. https://doi.org/10.1007/s10021-01900404-7
224
M. B. Roy et al.