Drainage basin

Question 1

Movement of water in a drainage basin

Answer 1

The main input of water into a drainage basin, happens by precipitation through rain or snow. Then interception happens when rain doesn’t reach the soil surface because it is intercepted by vegetation. Then evaporation can happen, and then water runs down a plant stem. Then the water is stored in the surface. Then surface run-off happens, which is a transfer, the water flows over the surface of the river basin or infiltration can happen, which is when water soaks into and moves through soil. The water is then stored in the soil and then percolation happens when the water moves through soil, and it can travel down into the rocks. Then groundwater is stored in porous rocks. Then it is transferred through groundwater flow back towards the sea. Then the water is held in a river or stream channel.

Question 2

Human factors affecting hydrological cycle:

Answer 2

Urban areas may have impermeable concrete and tarmac surfaces, which reduce infiltration to soil.
Deforestation reduces interception as there are no leaves or tree trunks to soak up the rainwater - it increases discharge and increases flood risk.

Question 3

Physical factors affecting the hydrological cycle:

Answer 3

some soils such as clays, absorb water at a slower rate than sandy soils.
soils absorbing less water results in more run-off overland into streams.
Water falling on steeper sloped land runs off quicker.