the majority of the geography Junior Cert exams over the years had a question on rivers so chances are if you're about to set your Junior Cert you will most likely get a question on rivers so in today's video I'm gonna be revising the entire topic as fast as possible all right so let's begin we'll start off with the river terms so as you can see from this diagram here we have the river source this is where the river begins next up we have the watershed this is the area of land where the precipitation or rain collects and drains off into the river here we have a tributary which is a smaller river that runs into the main river there is a confluence which is the point where the tributary meets the river we have an estuary which is the tidal part of the river and finally we have the river mouth which is a part of the river where it meets the sea so now that we have all the terms out of the way we can move on to the three different stages of the river the river can be separated into three different stages these are the youthful stage the mature stage and the old stage we will start off by talking about the youthful stage of the river this stage of the river has a steep slope fast moving water and often forms a v-shaped valley next up is the mature stage of the river this is a gentle slope and forms a valley with a wide floor and reasonably gentle sides lastly we have the old age stage which is an almost flat slope and runs very slowly true flat lowland so those were the three stages of the river so now I'm gonna move on to the processes of erosion that occur on rivers to start off we have hydraulic action this is the force of moving water eroding the riverbed and river banks the faster the water the greater the force and the more erosion dopy then we have abrasion this is where rocks and stones carried by the river known as its load are dragged and scraped off the floor the river making it deeper next we have attrition this is where the rivers load collides and breaks down into smaller pieces and finally we have solution this is where chemicals in the river actually dissolve the rock on the riverbed that's the basics of everything you need to know about River erosion now we're gonna move on to river transport River transport is how the river moves its load there are a few different types of transports that you need to learn about there's rolling and dragging where the river moves heavy stones and rocks bouncing which is similar to rolling and dragging just with smaller stones and rocks then we have suspension which is small stones and pebbles that are actually floating in the water and then we have solution which is tiny bits of stone that have dissolved into the water and finally we have floatation the we're leaves and sticks flowed along the top of the water so that's all the modes of transport covered so now we're gonna move on to the various features of the river it's this part that's most likely to come up in the exam so pay close attention we'll start off by going through some of the features of the youthful River interlocking Spurs occur where the stream is not strong enough to erode the interlocking Hill so it is forced to flow around the hills next up we have a v-shaped valley which forms when the river arose a valley in a process called vertical erosion the valley sides are broken down through weathering and this weather material falls into the river over time and creates steep valley sides finally we have a waterfall a waterfall forms when the youthful River flows over a Hard Rock which is next to a softer rock the softer rock gets eroded faster than the hard rock and forms a waterfall the main types of rosin here is hydraulic action and abrasion falling water and stones create a plunge pool in the soft rock the hard rock above the plunge pool is under cost' and collapses this causes the waterfall to erode upstream over many years some well known examples of waterfalls include Niagara Falls in Canada Victoria Falls in Zambia and Angel Falls in South America so now that we're done all the features of the youthful stage of the river we can move on to the mature stage the first feature of a mature River meanders are bends or curves in a river as the land is much flatter than it was in the useless stage the river tends to swing from side to side as it does this the current will be stronger on the outside of the bend and so erosion will take place while on the inside of the bend the current flows more slowly so deposition which is the unloading of the river's load will take place lastly we're going to move on to the features of the old age River the first feature of the old age River are oxbow lakes these are horseshoe shaped lakes during floods there will be an increase in the amount of speed and volume of a river so as the river comes to a tight meander that a Kanako around it simply burst its banks and cuts through the bend the water which flows around the bend will now be flowing slowly and so deposition will take place over time the meander will become cut off from the main river because of deposition the cut off meander is then called an oxbow lake the second and last feature of an old age stage river is a levee levees are long narrow ridges of alluvium found along the banks of many old rivers they are formed as a result of flooding each time the river floods it'll carry its load out onto the floodplain as it has a great deal of energy however when the flood subsided is not have enough energy to carry the load back into the channel so it deposits it after numerous floodings these deposits build up to form levies lastly we've looked at all these features we can now learn about humans relationships and interactions with rivers a case study for this is dam building in Ireland here is a video of arid necrosha on the river Shannon this is where the ESB built a hydroelectric power plant to generate electricity a dam was constructed across the river valley behind this dam the trapped water has risen to create an artificial a damming our rivers has many benefits such as creating free electricity but it can also have its disadvantages like flooding fertile farmland and that pretty much summarizes everything you need to know about rivers for the jr. sir geography exam I hope you enjoyed my summary and if you have any questions be sure to let me know in the comment section below if you enjoyed the video please be sure to give it a like also let me know what topics you'd like me to cover next for more videos be sure to subscribe and with that said thank you guys for watching