Formation, Migration, and Morphodynamic Alteration of 50 Channel Bars in Darjeeling Himalayan Piedmont Zone, India

Abstract

Channel bars are common, striking fluvio-geomorphic depositional features of alluvial rivers. The study of this article has aimed to investigate the formation, migration, and morphodynamic alteration of channel bars (n = 50) in gravel braided alluvial rivers in Darjeeling Himalayan Piedmont zone. Dynamics of micro to meso bar deposition is mainly accomplished by the channel gradient, huge upstream landslide, and variation of discharge. Multi-criteria analysis method has been used to explain the variation of principal component analysis (PCA1, PCA2, and PCA3), both monsoon to post-monsoon. Bridge scouring, empirical aggradation, and degradation values are 0.1 to 1.05 m and [Formula: see text]. Migration, re-generation, and degradation of the micro bars with their optimum morphology show changes during the rainy season. In the upper ([Formula: see text]), middle ([Formula: see text]), and lower ([Formula: see text]) piedmont region, the bar dynamic area are 0.12 to 0.71, 0.12 to 2.83, and 0.10 to 5.43 km2, respectively. In total, 58% to 72% stability of the channel bars is observed in the upper piedmont region. The coefficient of determination ( R²) of channel bar area and width shows positive (0.63) relation.

2021: The New Normal and the Air, Soil and Water Research Perspective

“…Among the wide variety of topics covered by ASW during 2020, most of them have been devoted precisely to deal with some of the Global Issues highlighted by UNF earlier this year by assessing the impact and uptake of heavy metals, 1,2 climate change effects and adaptations, 3,4 the use of novel materials and processes for water treatment, [5][6][7][8] social values perception of restoration economy, 9 plastic debris, 10 soil erosion, management practices and human health, [11][12][13] PM10 concentration, 14 indoor environments, 15 and riparian restoration. [16][17][18][19][20] Also, we are happy to share with the readers the first collaborative review paper written for twenty editors belonging to the soil section to highlight the challenges that soil scientists have to face in this new era from a transdisciplinary overview of relevant topics. 21 In this review, we also consider the relevance of micro-plastics as an emerging potential pollutant with the potential to negatively affect the world's soils, and now are even more important due to the residues of face masks (produced from polymers) used during the COVID-19 pandemic.…”