Impact of forest degradation on streamflow regime and runoff response to rainfall in the Garhwal Himalaya, Northwest India. Issue 7 (19th May 2017)

• Record Type: Journal Article
• Authors: Qazi, Nuzhat Q.; Bruijnzeel, L. Adrian; Rai, Shive Prakash; Ghimire, Chandra P.
• Is Part Of: Hydrological sciences journal. Volume 62:Issue 7(2017)
• Page Start: 1114
• Page End: 1130
• Publication Date: 2017-05-19
• Subjects: baseflow -- forest disturbance -- forest hydrology -- headwater hydrology -- land degradation -- soil water retention -- storm flow; Hydrology -- Periodicals; 551.4805
• DOI: 10.1080/02626667.2017.1308637
• Languages: English
• ISSNs: 0262-6667

Abstract

ABSTRACT: Baseflows have declined for decades in the Lesser Himalaya but the causes are still debated. This paper compares variations in streamflow response over three years for two similar headwater catchments in northwest India with largely undisturbed (Arnigad) and highly degraded (Bansigad) oak forest. Hydrograph analysis suggested no catchment leakage, thereby allowing meaningful comparisons. The mean annual runoff coefficient for Arnigad was 54% (range 44–61%) against 62% (53–69%) at Bansigad. Despite greater total runoff Q t (by 250 mm year – 1 ), baseflow at Bansigad ceased by March, but was perennial at Arnigad (making up 90% of Q t vs. 51% at Bansigad). Arnigad storm flows, Q s, were modest (8–11% of Q t ) and occurred mostly during monsoons (78–98%), while Q s at Bansigad was 49% of Q t and occurred also during post-monsoon seasons. Our results underscore the importance of maintaining soil water retention capacity after forest removal to maintain baseflow levels.EDITOR D. Koutsoyiannis; ASSOCIATE EDITOR D. Gerten