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Classification of Soil Water
Published in A. Zaman, Md. Hedayetullah, Sustainable Water Resource Development and Management, 2022
Rainwater running down according to the slopes ends up merging to form small streams which then channel into a river. Due to the kinetic energy of the moving water, the river develops various landforms through channel-making processes. Rivers refer to any natural stream or waterways. Lakes refer to any large body of water surrounded by a huge area. The basis of assuming rivers and lakes is the hydrological cycle part of rain forming media. The hydrological cycle refers to the movement of water from the atmosphere to Earth’s surface and ultimately to the oceans. Specific variations of the relative significance of the various components of the hydrological cycle estimate the volume of water held for rivers and lakes. The catchment collection guide to a river is known as the drainage basin. Drainage basin lithology and structural fabric determine the type of drainage pattern that a river displays. Sediment transport ability is strongly linked to relief. The total energy available for river sediment transport is the equivalent of a 7.5-kW engine removing material from 1 to 2 km for 24 h a day. Floods are shown to be an important part of the normal hydrological, geomorphological, and ecological functioning of a river. It is argued that rivers should be seen as an active system.
Impact of Urbanization on Flooding
Published in Saeid Eslamian, Faezeh Eslamian, Flood Handbook, 2022
A floodplain is flat land along a stream or river that is periodically flooded. Historically, many towns have been built on floodplains due to access to fresh water; the fertility for farming; cheap transportation through the waterway; and ease of development of flat land. However, flood damage has become the worst natural disaster in history; for example, the 1931 China Yellow River floods are estimated to have killed millions. Development along rivers and floodplains in urban areas has increased the floods dramatically in floodplains. The effect of urbanization on the floodplain will be summarized. Meanwhile, flood reduction approaches will be introduced for better planning, design, and management in floodplains.
Cascading process systems
Published in Richard J. Chorley, Stanley A. Schumm, David E. Sugden, Geomorphology, 2019
Richard J. Chorley, Stanley A. Schumm, David E. Sugden
There are three components of the total sediment load of a river: the dissolved load or materials in solution; the suspended load or the sediment held in the water by its turbulence; and bedload or the sediment moving on or near the bed. The size of the particles moved in suspension changes with flow velocity and turbulence, but the larger particles quickly return to the bed. Further discussion of the components of total sediment load will be presented in Chapter 12.
Assessment and analysis of morphometric characteristics of Lake Tana sub-basin, Upper Blue Nile Basin, Ethiopia
Published in International Journal of River Basin Management, 2023
Bitew G. Tassew, Mulugeta A. Belete, K. Miegel
Generally, a source of a river can be mountains or hills, ice and snow melt, springs and Lakes. Lakes with outflowing streams can become the headwaters of rivers, but only if they do not have streams that flow into them (the inflowing stream – not the lake – would be a source of the river). From the above definitions of the different scholars and different sources Lake Tana cannot be the sources of the Blue Nile River. This is because Lake Tana has more than 40 inflow rivers where Gilgel Abay, Megech, Ribb and Gumera are the main ones (Kebede et al., 2006). This study found that the longest river flowing towards the lake is the Gilgel Abay river (229.4 km) which its headwater (Gish Abay spring) is the source of the Blue Nile River. Other main tributaries (Megech, Ribb and Gumera) have 194.4, 161.0 and 139.2 km respectively from the outlet of the lake.
Integration of SAR and multi-spectral imagery in flood inundation mapping – a case study on Kerala floods 2018
Published in ISH Journal of Hydraulic Engineering, 2022
Jesudasan Jacinth Jennifer, Subbarayan Saravanan, Devanantham Abijith
The glossary of the report of Intergovernmental Panel on Climate Change (IPCC), defined flood as ‘the overflowing of the normal confines of a stream or other body of water, or the accumulation of water over areas that are not normally submerged. Floods include river (fluvial) floods, flash floods, urban floods, pluvial floods, sewer floods, coastal floods, and glacial lake outburst floods’ (Field et al. 2012). Over the years, the flood event has been a significant threat and has devastated many lives and properties (Mishra et al. 2018). Furthermore, the onset of flood has led to landslides, soil erosion, drought and epidemics (Paudyal et al. 2013). With the combined effects of the aftermath events, the consequences of the flood event have even more distressed the affected region and its habitat (Ghatak et al. 2012; Dewan 2015). The need for mapping of floodplains has been highly prioritized with the onset of hydrological disasters due to climate change. The floodplains are defined as ‘the areas that are periodically inundated by the lateral overflow of rivers or lakes, and/or by direct precipitation or groundwater; the resulting physiochemical environment causes the biota to respond by morphological, anatomical, physiological, phenological, and/or ethological adaptations, and produce characteristic community structures’ (Junk et al. 1989).
When does a road become a river? Why hydrologists and water planners need to move beyond averages
Published in Australasian Journal of Water Resources, 2018
Katherine A. Daniell, Trevor M. Daniell
Indeed, recently there have been examples of cars floating down roadways in the US, UK, Europe and Australia. In an increasingly unnatural world (Abramovitz 2001), many of our understandings of what is ‘natural’ are indeed coming under scrutiny. Since there are now UNESCO heritage listings of ‘novel’ ecosystems such as the Ord River (see Camkin 2011 for a useful review of the history of this place) and we still classify flooding, cyclone, drought or bushfire damage to (potentially poorly cited or constructed) properties as ‘natural disasters’ (Taylor 2018), it is easy to see that this distinction of what is ‘natural’ or ‘unnatural’ is becoming blurred. Thus looking again at whether a road can really be considered as a river, we can go back to the Oxford Dictionary definitions and see how a river is perceived. Firstly, a river can be defined as ‘A large natural stream of water flowing in a channel to the sea, a lake or another river’ or more simply as ‘A large quantity of a flowing substance’. Obviously, under the second definition a road could be defined as a river and potentially under the first if again our interpretation of ‘natural’ is as flexible as current common usage!