Rivers

Question 1

Give me 4 types of soft engineering

Answer 1

1) Flood plain zoning, Afforestation, River restoration, Wetland establishment

Question 2

What is a drainage basin?

Answer 2

An area of land that is drained y a river and its tributaries. A watershed separates drainage basins

Question 3

Describe what happens in the hydrological cycle

Answer 3

Water is stored in the atmosphere, then it falls to the ground in the form or precipitation, it is stored in the snow and ice on a mountain before the end melts and it runs off into the streams creating the source. Tributaries and confluences flow into the main river and vegetation storage occurs as rainfall is intercepted by leaves. Evapotranspiration can occur there also. Surface run off adds to the vegetation storage as the water passes over the ground and is intercepted by the plants. The water can be then infiltrated and travels to the river through either surface run off, through flow or ground flow. The water flow can travel to fresh water storage such as lakes. The river flows to the mouth. Evaporation occurs a dwarf particles in river turn to vapour where it travels to atmosphere and is stored in the form of a cloud.

Question 4

What is percolation ?

Answer 4

When the water moves downward through the soil to the point of ground flow

Question 5

What is through flow?

Answer 5

The downhill transfer of water in the soil layer to the river

Question 6

What is ground flow?

Answer 6

The downhill transfer of water below the water table to reach the river

Question 7

What does a hydrography show?

Answer 7

How the water flows on a drainage basin in response to a period of rainfall

Question 8

What are the 5 stages of the soil moisture budget

Answer 8

1) soil moisture surplus
2) soil moisture use
3) soil moisture deficiency
4) soil moisture recharge
5) field capacity has been reached

Question 9

What is soil moisture surplus ?

Answer 9

The store is full giving a surplus of soil moisture for plant use and it runs off into streams (due to lots of precipitation)

Question 10

What is soil moisture use?

Answer 10

Plants are relying on the stored water as there is a lack of precipitation

Question 11

What is soil moisture deficiency?

Answer 11

Lack of water so plants start to die

Question 12

What is soil moisture recharge?

Answer 12

Precipitation occurs again and the soil water store starts to be filled up again.

Question 13

What is field capacity has been reached from the soil moisture budget?

Answer 13

The soil water store is full and cannot hold any more water

Question 14

What are the 4 types of rejuvenation landforms

Answer 14

Knick points, river terraces, entrenched meanders and ingrown meanders

Question 15

What is an ingrown meander and now is it formed

Answer 15

A type of incised meander. Happens as the base level falls (slowly) due to eustatic or isostatic change, meaning the river down cuts, creating the steep sides. Vertical and lateral erosion can occur as it is a process and therefore creating a typical asymmetrical meander form

Question 16

What is an entrenched meander and how is it formed?

Answer 16

Type of incised meander. There is a rapid change in the base level of the river due to isostatic or eustatic change, causing only vertical erosion to occur quickly as the river downcuts. It creates a symmetrical meander.

Question 17

What is a river terrace and how is it formed

Answer 17

A remain or a former floodplain which has been left at a higher level due to eustatic or isostatic change. The river has more energy to erode as it tries to get back down to base level, therefore vertical erosion downcuts into a floodplain, leaving the old floodplain above

Question 18

What are knick points and how are they formed?

Answer 18

They are a sharp break of slope in the smooth, concave long profile of the river. It is usually marked by the presence of a waterfall. It is created because of the change in base level meaning the river has more energy to vertically erode. The knick point retreats upstream overtime until it adjusts to the new base level