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The active and abandoned coalmine overburden (OB) dumps are prone to slope instability under the influence of external agents. Estimating the mechanical reinforcement imparted by the grassroots on the coalmine overburden dumps is vital. This paper discusses the effect of organic amendment on the growth characteristics and root distribution of native grass Dendrocalamus strictus species (common name: Bamboo ) in the Jharkhand region, India. A pot experiment was conducted wherein the OB was amended with different proportions of cow dung (OA) and garden soil (GS) to be used as growth substrates known as treatments (T1-T5). A pot having only GS (T6) was used as a control. The growth of six D. strictus saplings under each treatment was monitored for survival, shoot height, and canopy area. The root distribution, root area ratio ( RAR ) with depth, root tensile strength ( T r ) vs. root diameter ( d ) relationship, and variation of additional cohesion (root cohesion, c r ) with depth were studied for each species (Wu method). The pot experiment shows that the chosen grass can survive on the OB dumps with a suitable external amendment and can exhibit a well-developed root system and produce higher root reinforcement when allowed to grow under unrestricted conditions.

As a part of the monitoring process of the main polluting tributary of Loktak, the paper analyzed the water characteristics of the main polluted stretch of Nambul river i.e. Imphal Urban region. The results showed low pH (6.23 ± 0.32), high electrical conductivity (1373 ± 50.33 µSm -1 ), high turbidity (25.40 ± 0.90 NTU), poor dissolved oxygen content (0.53 ± 0.24 mgL -1 ), high nitrate, and phosphate concentrations (9.27 ± 0.40 and 2.05 ± 0.10 mgL -1 , respectively). The Water Quality Index values indicate that Nambul river is unfit for drinking. Moreover, the Sodium Percentage, Sodium Adsorption Ratio, and Kelly's Ratio revealed the unsuitable nature of the river for irrigation. Therefore, in order to clean the river water, lab scale microcosm experimentation was carried out to highlight the potential of the dominant macrophytes viz. Eichhornia crassipes (Mart) Solms and Pistia stratiotes (L.) as phytofilters. The results showed increased pH (7.6 ± 0.11 and 7.5 ± 0.1), higher dissolved oxygen content (5.87 ± 0.30 and 3.28 ± 0.30 mgL -1 ), less turbidity (0.60 ± 0.25 and 0.40 ± 0.15 NTU) and reduced nitrate and phosphate concentrations (0.37 ± 0.03 and 0.52 ± 0.01 mgL -1 , and 0.534 ± 0.025 and 0.346 ± 0.01 mgL -1 , respectively).Novelty statementThe present study showed the deteriorating water quality of Nambul river, the main polluting source of Loktak - a Ramsar site in the Montreux records.Water Quality Index calculated was above the unsuitable level for drinking at all the sampling locations in the Imphal Urban region.Sodium percentage, sodium adsorption ratio and Kelly's ratio were above the desired limit, making the river water unfit for irrigation.Further, the microcosm experimentation showed that the dominant macrophytes viz. Eichhornia crassipes (Mart) Solms and Pistia stratiotes (L.) can control the pollution level of Nambul.