rivers transport 1.2

Question 1

what is the remaining energy used for in rivers

Answer 1

used to transport sediment after river has overcome friction

Question 2

what are the three types of load in the river

Answer 2

bed load
suspended
dissolved or solution load

Question 3

define bed load

Answer 3

consists of larger particles like pebbles

Question 4

define suspended

Answer 4

consists of very fine particles such as clay or silt that cannot dissolve in water but are dislodged and carried by fast moving river

Question 5

define dissolved or solution bedload

Answer 5

consists of minerals dissolved in water and carried within water in river

Question 6

define traction process

Answer 6

largest of particles transported by traction
rolled and pushed along river bed eroding bed by abrasion and the particles attrition in the process because river does not have enough energy to move these large particles in any other way

Question 7

define saltation process

Answer 7

pebbles and gravel are slightly smaller particles
load bounces or hops and skips along river bed because river has enough energy to lift particles off bed but the particles are too heavy to travel by suspension

Question 8

define suspension

Answer 8

when material made up of very fine particles like clay and silt lifted as a result of turbulence and transported by the river

Question 9

why do rivers appear muddy

Answer 9

faster flowing turbulent rivers carry more suspended material which is why rivers appear muddy as they are approaching bank full discharge where if the river has any more water it would flood its banks and towards the mouth of the river
most of the rivers load transported by suspension

Question 10

define solution process

Answer 10

when dissolved material carried by river often happens in areas where the geology is limestone or chalk and is dissolved in slightly acidic rainwater

Question 11

define depostion

Answer 11

process whereby eroded material dropped or deposited
this happens when river loses energy
how can a river lose energy
river deposits its largest or heaviest sediment first while finer sediments deposits last

Question 12

how can a river lose energy

Answer 12

when discharge is reduced when rainfall reduces or evaporating increases
when there is increased friction close to riverbanks
such as when river overflows its banks and deposits material on a flood plane and in shallow areas which leads to the speed of river reducing since there is more friction and therefore energy reduces and so too does its ability to transport material
when there is increased load in the river
gradient of river’s course flattens out
when river meets the sea