Table of Contents
How is river discharge affected by physical factors?
How is river discharge affected by physical factors? Impermeable Rock (e.g. granite) – Water is unable to infiltrate through, resulting in more surface runoff, increasing volume of the channel and its speed. This also means that the speed of the river increases.
What causes river discharge to increase?
Discharge changes whenever you add or take away water. In a hot area, some discharge will be lost through evaporation. When it rains, the river’s discharge will increase, too. Last of all, the river’s discharge will increase when another river joins it to make one larger river.
What increases water discharge?
Sexual arousal can trigger an increase in watery discharge. When you’re sexually aroused, blood flushes to the vagina and triggers the release of lubricating fluids. You may notice an increase in discharge following sexual intercourse.
What factors influence discharge?
The discharge from a drainage basin depends on precipitation, evapotranspiration and storage factors. Drainage basin discharge = precipitation – evapotranspiration +/- changes in storage.
How can physical and human factors increase the risk of flooding?
Human factors increasing flood risk:
- urbanisation , because towns and cities have more impermeable surfaces.
- deforestation , because removing trees reduces the amount of water intercepted and increases run-off.
How does human activities change river discharge?
The most significant impacts of human activity on WD occurred in the 1980s, where the contribution of human activities to WD increase was 56%. Deforestation in the watershed will lead to soil erosion and water loss, which will increase water discharge.
How do human activities change river discharge?
What does river discharge depend on?
The river’s discharge at that location depends on the rainfall on the catchment or drainage area and the inflow or outflow of groundwater to or from the area, stream modifications such as dams and irrigation diversions, as well as evaporation and evapotranspiration from the area’s land and plant surfaces.
What factors and physical causes contribute to a flood?
Why do floods occur?
- volume, spatial distribution, intensity and duration of rainfall over a catchment.
- the capacity of the watercourse or stream network to carry runoff.
- catchment and weather conditions before rainfall.
- ground cover.
- tidal influences.
How can humans cause rivers to flood?
The direct anthropogenic causes include land use change, river channel modifications and increased activities in areas vulnerable to floods. Thousands of square kilometres of impermeable surfaces have been created, coastal urbanization has been extensive.
How human activities can increase discharge?
1. Drainage systems that have been created by humans lead to a short lag time and high peak discharge as water cannot evaporate or infiltrate into the soil. This means infiltration levels decrease and surface runnoff increases. This leads to a short lag time and an increase in peak discharge.
How does increasing runoff impact stream discharge?
Increased stream runoff means smaller amount of rain will cause the stream to reach flood stage than before the alterations to the land. The stream will flood more frequently. You see that water concentrates over the concrete pavement and nearby lawn areas are not flooded.
What are the factors that affect river discharge?
Sunday, 20 March 2016. Factors affecting river discharge. Weather. A lot of rain causes higher river levels, whereas less rainfall or prolonged dry periods will result in lower river levels due to both the volume of rain and the fact that it will take longer for the rainwater to reach the river.
What causes the level of a river to increase?
An increase in discharge causes river levels to increase. Flooding occurs when the bankfull capacity of a river is exceeded (water spills over the banks of the river). There are a range of physical factors that can lead to flooding.
How does a hydrograph show the base flow of a river?
A storm hydrograph. The starting and finishing level show the base flow of a river. The base flow is the water that reaches the channel through slow throughflow and permeable rock below the water table. As storm water enters the drainage basin the discharge rates increase.
Why do steep slopes affect the flow of a river?
Steep slopes encourage fast run off as the water spills rapidly downwards due to gravity. On gentle slopes, absorption into the land reduces the volume of water reaching the river. Important in determining how much water infiltrates and how much stays on the surface.