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Mixing diagrams showing Na-normalized molar ratios in the Narmada River basin. Plots (a and c) showing the relationship of Ca 2+ / Na + vs. HCO 3 À /Na + for the mainstream and the tributaries and plots (b and e) showing the relationship for Ca 2+ /Na + vs. Mg 2+ /Na + . The data in these plots (a–d) illustrate significant positive correlations for both multiannual and spot samples in the mainstream and the tributaries. To avoid bias among the two different sets of data, spot samples were not corrected for atmospheric input.
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The Narmada River in India is the largest west-flowing river into the Arabian Sea, draining through the Deccan Traps, one of the largest flood basalt provinces in the world. The fluvial geochemical characteristics and chemical weathering rates (CWR) for the mainstream and its major tributaries were determined using a composite dataset, which includ...
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Context 1
... and 3.15 (average: 1). Similar to the observation of Dessert et al. (2003) for the Hawaiian Rivers, a few samples from multiannual data also show high HCO 3 À /Na + ratios (>10). A significant linear correlation between Na-normal- ized molar ratios of Ca 2+ vs. HCO 3 À and Ca 2+ vs. Mg 2+ were observed for both spot and multiannual datasets ( Fig. 5a and b). Plots of Na-normalized molar ratios ( Fig. 5a and b) show that approximately half of the Narmada basin samples occur outside the range determined for average continental silicate rock ( Gaillardet et al., 1999) but fall parallel to trend line between silicate and car- bonate end members. Dessert et al. (2003) explained this pattern ...
Context 2
... of Dessert et al. (2003) for the Hawaiian Rivers, a few samples from multiannual data also show high HCO 3 À /Na + ratios (>10). A significant linear correlation between Na-normal- ized molar ratios of Ca 2+ vs. HCO 3 À and Ca 2+ vs. Mg 2+ were observed for both spot and multiannual datasets ( Fig. 5a and b). Plots of Na-normalized molar ratios ( Fig. 5a and b) show that approximately half of the Narmada basin samples occur outside the range determined for average continental silicate rock ( Gaillardet et al., 1999) but fall parallel to trend line between silicate and car- bonate end members. Dessert et al. (2003) explained this pattern for the rivers draining basaltic terrains as a result of ...
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The chemical composition of siliciclastics from Mesoproterozoic Kaimur Group, Vindhyan Supergroup have been investigated to determine and appraise the influence of the weathering, hydraulic sorting and recycling processes upon source rock signature. The studies pertaining to the relationship between major, trace and REE and the grain size variation...
Atmospheric CO2 and global climate are closely coupled. Since 800 ka CO2 concentrations have been up to 50% higher during interglacial compared to glacial periods. Because of its dependence on temperature, humidity, and erosion rates, chemical weathering of exposed silicate minerals was suggested to have dampened these cyclic variations of atmosphe...
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Citations
... The stable carbon isotopic characteristic of DIC (δ 13 C DIC ) is an effective tool for understanding the dynamics of biogeochemistry of river systems and has been widely used to trace the sources and processes involved in the riverine carbon cycle (Aucour et al., 1999;Marfia et al., 2004;Das et al., 2005). Numerous geochemical studies have been conducted on the Tibetan plateau (Qin et al., 2006;Wu et al., 2008;Jin et al., 2011;Zhang et al., 2019), the Ganges (Krishnaswami and Singh, 1998;Tripathy and Singh, 2010), the Brahmaputra (Hartmann et al., 2009), and the peninsular rivers of India (Das et al., 2005;Jha et al., 2009;Gupta et al., 2011;Gurumurthy et al., 2012); in comparison, very few studies have been conducted in the Indus River Basin (IRB) (Pandey et al., 1992;Karim and Veizer, 2000;Ahmad et al., 1998), with no systematic study reported from the Upper Jhelum River Basin (UJRB) of the IRB in the north-western Himalayan region. The studies in IRB focused on the semi-arid region of Ladakh (Cold Desert), where physical erosion rates exceed chemical weathering rates (Ahmad et al., 1998). ...
... The reason may be the strong impact of mass transport via runoff, the significant variability of annual runoff rather than temperature, and the higher discharge during summer that can suppress the role of temperature in controlling the dissolved loads. The insignificant correlation between temperature and chemical weathering rates has also been observed in Indian Peninsular rivers like the Narmada (Gupta et al., 2011). Moderately high correlations are observed between CWR carb and Area (R 2 = 21, p < 0.001), and Relief (R 2 = 22, p < 0.001). ...
... The study covers the upper stretch of Narmada River, i.e. starting from Amarkantak to Jabalpur [coordinates: 21°09´N to 23°08´N; 79°04´E to 81°78´E; annual rainfall: ~140 cm; and catchment area: ~22,385 km 2 ] (Figure 1). The study area catchment falls in Deccan Trap region dominated by basaltic rock [32]. Additional information about the hydrogeology of the upper Narmada basin can be found in the literature [33]. ...
Owing to the rapid industrial and socioeconomic development, the heavy metal concentration in the river is gradually increasing, it has the potential to threaten the aquatic environment and mankind. The present investigation deals with the quantification and fractio-nation of heavy metals from the sediments of the Narmada River. The presence of these heavy metals can be toxic to human health and aquatic life, therefore different pollution indices were evaluated to identify the degree of threat that might be imposed by these contaminants in the surface water and sediment. In this context, risk assessment code (RAC), hazard quotient (HQ), hazard index (HI) and total cancer risk (TCR) were calculated to examine the risk of heavy metal contamination on the human being. The important heavy metals and their concentration (in mg/kg, dry weight) have followed the following order, Fe > Al > Mn > Cr > Cu > Ni > Zn > Pb > Cd. Pollution indices classified the surface sediments under the uncontaminated to moderately contaminated category; the major responsible heavy metals for different pollution levels were Cr, Mn, Cu and Pb. The RAC identified Mn and Cd as potential heavy metals which may cause a high risk to aquatic organisms. HQ, HI and TCR values confirmed no human health risk. However, the Cr concentration present in surface sediments might cause cancer via ingestion in children. The insights obtained from this study shall aware and encourage the competent legislative bodies to plan an appropriate regular monitoring campaign and take necessary measures to improve the health of the river. ARTICLE HISTORY
... Therefore, the importance of MNT river systems in controlling the biogeochemistry of the Arabian Sea is expected to be significant (Ramaswamy and Nair 1994;Goswami et al. 2012). The Narmada and the Tapti rivers are well-studied for their hydrogeochemistry (Dessert et al. 2001;Sharma and Subramanian 2008;Gupta et al. 2011Gupta et al. , 2020; however, that of the Mahi River has been restricted to a few studies (Srivastava et al. 2011;Sharma et al. 2012Sharma et al. , 2013Sharma and Kumar 2018). These studies were confined to socio-economic dimensions investigating the quality and suitability of the river water for domestic and agricultural uses and lacked geochemical insights on the major sources, their contributions to dissolved loads, and the rates of chemical weathering and associated CO 2 drawdown occurring at the catchment scale. ...
... Table 1 gives the mean concentration of physicochemical parameters of Mahi River water. For comparative analysis data from the other west-flowing rivers (e.g., the Narmada and the Tapti) draining into the Arabian Sea are taken from previously published studies (Dessert et al. 2001;Sharma and Subramanian 2008;Gupta et al. 2011). ...
... The Piper plot ( Figure.B1) depicts the water type of the Mahi as Ca-Mg-alkalinity. Using the published data of the Narmada and Tapti rivers (Sharma and Subramanian 2008;Gupta et al. 2011), it was observed that both Narmada and Tapti fall under the Ca-Mg-alkalinity water type. Therefore, the water type of the MNT rivers identified from Piper plots is similar. ...
The geochemistry of rivers draining into the Arabian Sea has received lesser attention than their eastern counterparts draining into the Bay of Bengal. The major ion concentrations in the third-major river (Mahi) draining into the Arabian Sea have been reported. Hydrochemistry of seasonally collected samples (n = 67) during two consecutive years reveals that the average solute export and the cationic charges are ~ 1.2 and ~ 4 times their corresponding global average values. Generally, lower solute levels (except Ca) in the rainy season reflect the dilution effect. In contrast, the higher intensity of carbonate weathering out-weighing the dilution effect, aided by CaCO3 precipitation in summer, dominates the Ca dynamics. Chemical weathering in the catchment is mediated predominantly by carbonic acid, as evident from the alkalinity/(Ca + Mg) and SO4/(Ca + Mg) molar ratios. Using a forward model, the estimated average contributions from various sources to the cationic composition are atmospheric (5 ± 1%), evaporites and soil salts (27 ± 9%), silicates (39 ± 12%), and carbonates (29 ± 13%). Runoff exerts the dominant control on the weathering rates, with the best estimated average silicate (11 t km⁻² yr⁻¹), carbonate (22 t km⁻² yr⁻¹), and evaporite and soil-salt (8 t km⁻² yr⁻¹) weathering rates, which sums up to a dissolved chemical flux of ~ 41 t km⁻² yr⁻¹. The lower-bound estimate of CO2 consumption by silicate weathering of the Mahi basin is ~ 2.8 × 10⁵ mol km⁻² yr⁻¹, translating into CO2 consumption of ~ 9.7 × 10⁹ mol yr⁻¹. This is ~ 0.08% of the global average value (by silicate weathering) and is disproportionately higher than its fractional continental drainage area (~ 0.03%). Integrating the data of Mahi with those available for the other two major rivers (Narmada & Tapti), this study underscores the prominent role of these rivers in supplying solutes to the Arabian Sea and controlling the biogeochemistry of the Arabian Sea.
... Moreover, the surface properties of basalt, such as mineral coatings and roughness, influence the interaction between CO 2 and solid surfaces, which, in turn, affects the distribution and entrapment of CO 2 within the pore spaces. [213]. Basalt's geochemical properties not only facilitate initial capillary trapping but also contribute to the long-term stability of stored CO 2 . ...
The underground storage of CO2 (carbon dioxide) in basalt presents an exceptionally promising solution for the effective and permanent sequestration of CO2. This is primarily attributed to its geochemistry and the remarkable presence of reactive basaltic minerals, which play a pivotal role in facilitating the process. However, a significant knowledge gap persists in the current literature regarding comprehensive investigations on the reactivity of basaltic minerals in the context of CO2 sequestration, particularly with respect to different basalt types. To address this gap, a comprehensive investigation was conducted that considered seven distinct types of basalts identified through the use of a TAS (total alkali–silica) diagram. Through a thorough review of the existing literature, seven key factors affecting the reactivity of basaltic minerals were selected, and their impact on mineral reactivity for each basalt type was examined in detail. Based on this analysis, an M.H. reactivity scale was introduced, which establishes a relationship between the reactivity of dominant and reactive minerals in basalt and their potential for carbonation, ranging from low (1) to high (5). The study will help in choosing the most suitable type of basalt for the most promising CO2 sequestration based on the percentage of reactive minerals. Additionally, this study identified gaps in the literature pertaining to enhancing the reactivity of basalt for maximizing its CO2 sequestration potential. As a result, this study serves as an important benchmark for policymakers and researchers seeking to further explore and improve CO2 sequestration in basaltic formations.
... The stable carbon isotopic characteristic of DIC (δ 13 C DIC ) is an effective tool for understanding the dynamics of biogeochemistry of river systems and has been widely used to trace the sources and processes involved in the riverine carbon cycle (Aucour et al., 1999;Marfia et al., 2004;Das et al., 2005). Numerous geochemical studies have been conducted on the Tibetan plateau (Qin et al., 2006;Wu et al., 2008;Jin et al., 2011;Zhang et al., 2019), the Ganges (Krishnaswami and Singh, 1998;Tripathy and Singh, 2010), the Brahmaputra (Hartmann et al., 2009), and the peninsular rivers of India (Das et al., 2005;Jha et al., 2009;Gupta et al., 2011;Gurumurthy et al., 2012); in comparison, very few studies have been conducted in the Indus River Basin (IRB) (Pandey et al., 1992;Karim and Veizer, 2000;Ahmad et al., 1998), with no systematic study reported from the Upper Jhelum River Basin (UJRB) of the IRB in the north-western Himalayan region. The studies in IRB focused on the semi-arid region of Ladakh (Cold Desert), where physical erosion rates exceed chemical weathering rates (Ahmad et al., 1998). ...
... The reason may be the strong impact of mass transport via runoff, the significant variability of annual runoff rather than temperature, and the higher discharge during summer that can suppress the role of temperature in controlling the dissolved loads. The insignificant correlation between temperature and chemical weathering rates has also been observed in Indian Peninsular rivers like the Narmada (Gupta et al., 2011). Moderately high correlations are observed between CWR carb and Area (R 2 = 21, p < 0.001), and Relief (R 2 = 22, p < 0.001). ...
... The Narmada and the Tapi drain different geological areas (Fig. 1b). The Narmada flows through the Vindhyan Super Group and the Deccan Basalt (Gupta et al., 2011), whereas the Tapi River largely passes through the Deccan Basalt (Kale et al., 2003). Moreover, some fine sediments from the Peninsular Gneissic Rock may be transported northwestward to the eastern Arabian Sea by winter monsoon-driven shallow currents (Kessarkar et al., 2003), primarily settled on the western continental margin of India (Kessarkar et al., 2003;Goswami et al., 2012). ...
Analyses of mass accumulation rate (MAR), laser grain-size, clay mineralogy, and SrNd isotopic compositions of <2 μm and < 63 μm grain-size fractions have been applied to sediments from the International Ocean Discovery Program (IODP) Site U1456, which span the last 31 ka, in order to constrain (i) past changes in the relative proportions of the fine-grained detrital sediments derived from the Indus River and the Deccan Traps and the dynamics of sediment transport to the Laxmi Basin and (ii) past changes in Indian monsoon rainfall and latitudinal migration of Intertropical Convergence Zone since the last glacial period. Sr and Nd isotopes results combined with clay mineral assemblages suggest that clay-sized sediments at IODP Site U1456 derive mainly from the Indus River (70–90%), followed by a minor contribution from rivers draining the volcanic province of the Deccan Traps (10–30%). During the Last Glacial Maximum, clay mineralogy was dominated by illite and chlorite primarily derived from the highlands of the Indus River basin. The combination of lower temperatures and lower monsoonal rainfall during glacial times led to a reduction of smectite formation rates in the floodplains, while glacial erosion accelerated in the Himalayan and Tibetan highlands leading to the release of large quantities of illite and chlorite minerals into the Arabian Sea. In addition, glacial low sea-level stands allowed a connection between river mouths and the heads of deep-sea channels favoring the southward transfer of sediments to IODP Site U1456 by turbidity currents. Each maximum of the summer insolation curve, associated with a northward shift of the ITCZ and an intensification of summer monsoon rainfall (from 31 to 25 ka BP and from 12 to 8 cal ka BP), was associated with enhanced rainfall in the Indus floodplain which in turn led to an increase in the physical erosion and weathering of plain soils, which were rich in pedogenic minerals (such as smectite), and/or a higher production rate of smectite in the soils of the Indus floodplain. A compilation of three Nd isotopic composition records obtained at sites located on a N-S latitudinal transect in the eastern Arabian Sea have allowed us to establish the impact of sea level variations and latitudinal migration of the ITCZ over time on the sedimentation of the eastern Arabian Sea.
... High riverine HCO 3 fluxes from basaltic settings, such as Iceland (Gislason et al., 1996Stefansson and Gislason, 2001;Georg et al., 2007;Louvat et al., 2008;Eiriksdottir et al., 2013), the Deccan traps (Dessert et al., 2001;Das et al., 2005aDas et al., ,b, 2006Gupta et al., 2011;Babechuk et al., 2014), and Réunion Island (Louvat and Allègre, 1997;Rad et al., 2007), are widely interpreted as evidence that mafic minerals weather substantially faster than felsic minerals (Goldich, 1938) and that basalt weathering disproportionately contributes to long-term climate regulation (Nesbitt and Wilson, 1992;Dessert et al., 2003;Schopka et al., 2011;Hartmann et al., 2014;Moon et al., 2014;Ibarra et al., 2016). Estimates suggest that basalt weathering could account for $30-35% of the global atmospheric CO 2 consumption flux, even though basalt composes only $5-8‰ of the Earth's total land surface area (Suchet et al., 2003;Dessert et al., 2003). ...
This study examines the Ca isotope (δ44/40Ca) geochemistry of Icelandic rivers with the overall aims of improving the δ44/40Ca tracer, constraining solute sources, and addressing the hypothesis that basalt weathering disproportionately regulates Earth’s long-term climate. We report Ca isotope and elemental data for mainstem rivers, tributary streams, thermal and non-thermal springs, basalt, calcite, soil, vegetation, and sediment collected from the Skagafjörður region in North Iceland. Waters and calcite were further analyzed for their carbon isotope (δ¹³C) composition, and we conducted experiments to characterize δ44/40Ca values of riverine colloids, the clay-size fraction (<2 µm) of soil, and exchangeable leachates obtained from soil and bedload sediment. The dataset includes analyses of travertine and coexisting water samples collected from a CO2-rich spring (Hvanná river) in South Iceland.
Samples show a ∼2‰ range, with groundwater, the ultrafiltered fraction of river water, and hydrothermal calcite producing among the highest δ44/40Ca values and travertine, soil exchangeable Ca, and vegetation the lowest. Riverine δ44/40Ca values are on average ∼0.20‰ higher than those for basalt, which shows minimal isotopic variability. Mainstem glacial-fed rivers entering the Skagafjörður valley from the soil- and vegetation-free highlands have higher δ44/40Ca values than direct-runoff tributaries draining catchments to the north where pedogenesis is more pervasive. Riverine δ44/40Ca values correlate with Sr/Ca and Na/Ca ratios, as well as the saturation index of calcite (SIcal). Riverine δ¹³C values increase from ∼-8‰ (atmospheric) to ∼-3‰ (calcite) as SIcal values increase from highly-undersaturated to near-equilibrium. One watershed (Svartá river) shows unique trends, where riverine δ44/40Ca values and Sr/Ca ratios do not correlate, and soil exchangeable leachates produced anomalously high amounts of Ca. Clay-size fractions isolated from three horizons composing a brown andosol show slightly lower δ44/40Ca values than bulk basalt, but the values overlap with those for primary minerals. Colloids appear to have lower δ44/40Ca values than truly dissolved Ca. The proxy could be developed as a tracer for colloidal contributions to riverine dissolved loads, especially in soil-mantled catchments where the inputs appear most pronounced. Groundwater δ44/40Ca values correlate with pH, temperature, distance from the coast, and Sr/Ca ratios, all consistent with fractionation control yielding varying degrees of geochemical evolution. The combined riverine patterns largely reflect three-component mixing between basalt weathering, calcite weathering, and hydrothermal water inputs. Subsurface Ca isotope fractionation indirectly impacts riverine δ44/40Ca values by elevating the δ44/40Ca values of groundwater and hydrothermal calcite. This study highlights the significance of hydrothermal water inputs of Ca and HCO3 to Icelandic rivers, which have been previously underappreciated. Mixing calculations suggest that a maximum of ∼20% of the Ca in mainstem rivers derives from surficial basalt weathering. Small tributaries draining the flanks of the valley show the clearest signals of basalt weathering by atmospheric CO2, but these waters have much lower solute concentrations than those employed in previous attempts to estimate basalt weathering rates and parameterize the climate sensitivity of the basalt weathering feedback.
... The late Quaternary sedimentation largely occurred under alluvial fan and alluvial plain environments in the lower reaches and as braid bars and floodplains in the upper reaches (Rajaguru et al., 1995;Bhandari et al., 2005). Gupta et al., 2011). Grey boxes A, B and C mark the Dhadgaon, Punasa and Bhedaghat gorges respectively (after Gupta et al., 1999). ...
Bedrock gorges occurring on the Indian Peninsula are sites of intense erosive activity where thick sequences of fluvial sediments are conspicuously absent. We identified unusually thick and coarse fluvial sequences within the Dhadgaon (DG) gorge in the lower reaches of the Narmada River in central India. Stratigraphic interpretations, sediment character and optically stimulated luminescence (OSL) ages revealed episodic aggradation at ~70 ka and ~28 ka in response to tectonically induced steepening of the upstream channel gradient. Incision of the DG gorge and sedimentation of the alluvial fan downstream was facilitated by a climatically induced decrease in the sediment supply/discharge ratio in addition to the tectonic slope. The final evacuation of sediments from the DG gorge and incision of the Banganga channel occurred during the early Holocene. Collectively, the results show a major influence of tectonics, hillslope processes and lithology on aggradation–incision patterns supported by climatic conditions during the late Quaternary.
... The Narmada River is the fifth largest river in India. It originates from the Amarkantak plateau in the form of groundwater seepage, flows mostly through the Deccan Traps, and drains into the Arabian sea (Pandey and Khare, 2018;Gupta et al., 2011). On its way, the river passes through hills of the town of Mandla, the Marble Rock Gorge, and several notable waterfalls. ...
... On its way, the river passes through hills of the town of Mandla, the Marble Rock Gorge, and several notable waterfalls. Over 70% of the basin is occupied by Deccan basalt, while other considerable lithological features include Quarternary soils, sedimentary outcrops, and thick patches of other rocks (Gupta et al., 2011). A number of reservoirs have been constructed in the basin for a variety of purposes including water supply, irrigation, and hydropower generation. ...
The prediction of hydrologic conditions in watersheds has manifold applications, ranging from flood disaster preparedness to water supply and environmental flow management. In watersheds with scarce or no flow data, it is difficult to make accurate hydrologic predictions. Past work has used similarity in single-valued properties of the terrain (for example, drainage area, mean slope) as the basis to relate flow conditions in gauged watersheds to the ungauged ones. The resulting predictions show modest accuracy and have a weak physical basis. In this study, we develop a physics-informed machine learning approach to extract features that represent the hydrologic dynamics–width function and hypsometric curve. These two geomorphometric measures are computed using functional forms fitted to estimates derived from digital elevation data. Furthermore, dynamically-similar groups are identified based on results from unsupervised clustering and divergence measures. Our approach paves the way towards a flexible and scalable machine learning approach that can be used to assess hydrologic similarity and improve prediction, one informed by physics of surface flow generation and transport in watersheds. A case study involving 72 sub-watersheds in the Narmada River Basin (India) is used to illustrate the new methodology.
... To circumvent this problem, Rengarajan et al. (2009) and Rai et al. (2010) have used Mg and Si in the Chambal and the Ganga basin, respectively, as a proxy of silicate weathering. Likewise, Gupta et al. (2011) have used K in the Narmada basin to deduce the quantitative estimate for SER. However, the biogenic uptake of Si and its input from saline-alkaline soils, Mg supplied from carbonates, and K originated from plant debris can impede their efficacy in estimating the SER in river basins (Das et al., 2005;Gupta et al., 2011;Rai et al., 2010). ...
... Likewise, Gupta et al. (2011) have used K in the Narmada basin to deduce the quantitative estimate for SER. However, the biogenic uptake of Si and its input from saline-alkaline soils, Mg supplied from carbonates, and K originated from plant debris can impede their efficacy in estimating the SER in river basins (Das et al., 2005;Gupta et al., 2011;Rai et al., 2010). More recently, Bickle et al. (2018) have estimated that salts within the floodplains contribute to ∼18.6 ± 5.1 Gmol yr −1 of dissolved Na in the Ganga outflow. ...
We characterize here the saline‐alkaline soils composed of Na2CO3 and NaHCO3 in the Ganga floodplain and the peninsular basin using various chemical proxies and the isotopic composition of Sr. Abundance of saline‐alkaline soils in the Ganga floodplain and their higher solubility make them an important source of non‐chloride Na and other dissolved ions including Sr to the river waters. Inverse model based source apportionment of dissolved ions indicates ∼26%–71% of Na at the Ganga outflow is influenced by the saline‐alkaline soils; however, in some of the tributaries of the Ganga in the floodplain, for example, in the Gomti, this contribution exceeds 85%. The estimated silicate erosion rate by correcting for the saline‐alkaline soil contribution in the Ganga floodplain (∼5 tons km⁻² yr⁻¹) is less than one third of that of the Himalayan headwaters (16 tons km⁻² yr⁻¹) emphasizing the important role of physical erosion in controlling the chemical erosion in the mountain catchments compared to higher temperature and residence time in the floodplain. The silicate sourced dissolved fluxes from the floodplains are comparable to those from the Himalaya because of the vast drainage area of the floodplains and peninsular catchment. The findings of this study have direct relevance to studies on the determination of silicate weathering rates of not only the Ganga system, but also of other basins infested by saline‐alkaline soils such as the Columbia, the Colorado, the upper Rio Grande, the Missouri‐Mississippi river system, the Parana river, the Niger, the Nile, and the Orange.
