GUWAHATI, Feb 11: Researchers of Nagaland University have completed a pioneering GIS-based hydrological study that scientifically examines how geo-ecological conditions and human activities influence runoff and river flow in the Northeastern Himalayan hill region, an area long marked by data gaps and global scientific debate.
The research addresses a critical and contested question in Himalayan science – the true hydrological impact of land use change on river discharge, floods and environmental degradation, claims a statement issued by the university.
Beyond advancing scientific understanding, the study proposes a practical four-zone runoff classification—low, moderate, high and very high runoff zones—to support water resource planning, flood mitigation and integrated watershed management.
The methodology and findings are expected to benefit policymakers, planners and local communities, while also serving as a transferable model for similar fragile regions across the Himalaya and India.
Emphasising the role of the university in researching topics of vital importance to the local community and the Northeast, Prof. Jagadish K. Patnaik, Vice Chancellor, Nagaland University, said, “This work enhances our understanding of runoff patterns, flood risks, and sustainable water management in fragile hill ecosystems. Such research not only strengthens scientific knowledge but also supports informed policy and planning for the region’s environmental security and resilience.”
The study, titled ‘GIS Modelling to investigate geo-ecological and anthropogenic impacts on runoff and river flow in the Northeastern hilly region of India’, was conducted by K. Belho and Prof. M. S. Rawat from Nagaland University, along with Dr. Pradeep Kumar Rawat from Asian International University, Imphal.
The research was funded by Nagaland University through a Non-NET Fellowship and supported by the Ministry of Tribal Affairs, Government of India.
The findings were published in International Journal of Geographic Information System Research and Development, a peer-reviewed academic journal that publishes original research and applied studies on GIS theory, technologies, spatial analysis, and geospatial applications across disciplines.
Elaborating on the technical aspects of the Research, Prof. M. S. Rawat, Department of Geography, School of Sciences, Nagaland University, said, “We focused on four experimentally monitored watersheds in Kohima district. Our research team combined advanced geospatial techniques with systematic field-based hydrological measurements, which is an approach rarely attempted in the Indian Himalayas”.
“The study generated continuous stream discharge data across contrasting land-use systems, including dense forests, open forests, agricultural lands and urban landscapes, creating one of the first benchmark hydrological datasets for the Northeastern Himalayan region,” Prof. Rawat said.
Further, Belho said, “Our findings reveal stark contrasts in runoff behaviour across geo-ecological systems. Dense, undisturbed forest landscapes showed a strong capacity to absorb rainfall and sustain sub-surface flows during non-monsoon months, while urban and heavily modified landscapes generated high monsoon runoff and significantly reduced lean-season flows.”
The researchers quantified these differences through runoff ratios, clearly demonstrating how increasing anthropogenic stress amplifies flood risks while weakening water availability during dry periods.
