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This study focuses on heavy metals distribution and their ecological risk in river water, bed sediment, and suspended particulate matter (SPM) along the Ganga River basin. Overall abundance of the metals followed the sequence, Fe > Al > Mn > Pb > Ni > Cd > Cr > Zn > Co in water, Al > Fe > Mn > Zn > Cr > Cu > Ni > Co > Pb > Cd in bed sediment, while Al > Fe > Mn > Cr > Zn > Ni > Cu > Pb > Co > Cd in SPM. Among the abundant metals, Fe and Mn average concentrations exceeded BIS and WHO limits in river water. Similarly, Fe, Cd, and Zn, and most metals exceeded local background concentrations in bed sediment and SPM, respectively. Major ion chemistry in water signified carbonate weathering dominance during the time of sampling. Generally, Mn, Ni, Cu, Cr, and Co were derived from natural weathering and erosion, while Zn, Cd, and Pb were derived from both natural and anthropogenic sources. Metal index (MI) for river water showed that 27% of the locations were anthropogenically affected, whereas contamination factor and ecological risk assessment indicated highest contamination and risk from Cr and Cd in suspended sediments around urban centers in the middle basin. Furthermore, the confluence of Chambal and Yamuna increased heavy metal load in Yamuna and Ganga, respectively. The study highlighted the role of the water–sediment interaction indicating SPM is acting as a sink for metals followed by bed sediment.

Climate change puts estuaries at higher risk of flooding from the land, river, and coast by increasing sea levels and extreme weather events such as heavy rainfall. Meanwhile, sediment delivery from catchments and the seas is expected to play a crucial role in estuarine to keep up with sea-level rise (SLR), which will consequently affect estuarine hydrodynamics and flood risks in the future. Nevertheless, the actual impact of fluvial inputs, and specifically, the role of catchment management for the long-term estuarine development, is less known due to a lack of integrated catchment and coastal modelling works. Therefore, this study built a modelling framework that combined catchment hydrological and estuary hydro-morphological processes to understand the impact of catchment management, particularly natural flood management, on long-term estuarine evolution. A cellular automata model (Bentley, 2016) and HEC-HMS were applied for estuary and catchment modelling, respectively. The reforestation scenario with and without SLR (3 mm/year) for 100 years on a hypothetical catchment and estuary were tested. The reforestation effect was captured as the proportionally reduced catchment discharge and sediment delivery at the rainfall events compared to the baseline (non-reforestation) scenario. Preliminary results, however, showed the estuarine morphology is less sensitive to reforestation cases. In both management scenarios, SLR cases resulted in a 50 % increase in sedimentation in the estuary compared to non-SLR. Though due to rapid SLR, that sedimentation was not sufficient to keep tidal prism constant, and it was increased by 13% in 100 years as a result. The above results/sensitivities are based on simulation runs, with no tidal pumping, incorporating this may change these results. Further work such as introducing tidal asymmetry to the estuary model will provide a more comprehensive view of the fluvial impact on estuaries' long-term evolution. Bentley, I. (2016) A novel cellular automata based estuarine morphodynamic model. PhD. University of Glasgow. Available at: http://theses.gla.ac.uk/6821/.

One of the most enduring and culturally vibrant potamic societies in the world are the Māori peoples of Aotearoa/New Zealand. The creation of the prints featured in this article have emerged from a long-term and ongoing trans-disciplinary art-science project – Te Awa Rio/the River’s voicen– that has for the first time brought together river scientists, visual artists and the Te Atihaunui- a-Paparangi people or iwi (kin groups) of the Whanganui River of the North Island. Offered, with much humility, these works show how indigenous knowledge, an understanding of deep time human- environment entanglements, and a reconnection with the watery realm, can offer society a way to rethink how best to navigate through and beyond our current planetary crisis. Planetary wellbeing, in the past as well as in the present era of anthropogenic climate weirding, pandemics and environmental breakdown, has often been measured by the health of our rivers and by the partnerships, formal or informal, that communities make with them and the watery realm more generally (Macklin and Lewin, 2020). Water is the lifeblood of humankind, and without water to support vital biological and social functions, people cannot flourish. The early ‘hydraulic’ civilisations of Mesopotamia, the Huang He (Yellow River), Indus and Nile Valleys understood this very well (Macklin and Lewin, 2015) and the fate of these societies was intimately entwined with their stewardship of water resources and their resilience from the impacts of exceptional floods and droughts.

Linking river behaviour and drainage basin evolution to Quaternary environmental change, most notably the effects of climatic variability, tectonics, and human activity on runoff and sediment delivery, has a long history of research in the Mediterranean areas of Europe, North Africa, and the Near East. This field of research was initially stimulated by the (re)discovery at the beginning of the twentieth century of many Classical Period remains buried by river alluvium; perhaps the best known of which is the site of Olympia in western Greece (Huntington 1910). The widespread evidence for large-scale shifts in river channel positions and the rapid growth of deltas and coastal alluvial plains in historical times (Judson 1963; Raphael 1973; Kraft et al. 1980; and Chapter 13) also provided much impetus for this research. In addition, archaeological investigations carried out soon after the Second World War in Algeria (Gaucher 1947), Italy (Selli 1962), Libya (McBurney and Hey 1955) and Spain (Gigout 1959) resulted in the recovery of large numbers of Palaeolithic stone tools from Pleistocene fluvial deposits. These early examples of what has now become more widely known as ‘geoarchaeology’ (Davidson and Shackley 1976; Butzer 1977) or ‘alluvial archaeology’ (Macklin and Needham 1992) were, with their strong interdisciplinary focus, highly innovative and ahead of their time in the way they integrated archaeology, geomorphology, and geochronology. Building on this theme, the principal aim of this chapter is to consider how river systems in the Mediterranean region have responded to the environmental changes that took place during the Late Quaternary–a time interval corresponding approximately to the last 130,000 years. There are a number of reasons for choosing this period for reviewing river-environment interactions in the Mediterranean: 1. It encompasses the last glacial–interglacial cycle (c.130 to 10 ka) for which there is now abundant global evidence from polar ice cores, speleothem records, and lake and marine sediments, for both longand short-term changes in climate. These changes included massive reorganizations of the atmosphere-ocean-cryosphere systems—often over timescales of less than 100 years (Lowe and Walker 1997)—and they are clearly recorded in the Mediterranean region (see Allen et al. 1999 and Chapter 4).