Water Cycle Exam Qs Flashcards
Explain how water insecurity can cause social problems
Water insecurity= lack of access to clean water which can negatively deplete an individuals health since clean water is essential for drinking and food preparation.
Science proves that contaminated water sources can cause serious health problems that are linked to water borne diseases e.g. cholera
E.g. UN= 26% deaths from diarrhoea, 1.75bn cases of diarrhoea amongst children under 5, 3 mill cases of cholera, 11 mill cases of typhoid
Pose sig health problems to people no matter the age and can risk an impending death
Explain how water insecurity can cause economic problems
Can hinder agricultural production, causing farmers to miss out on profit
Agriculture relies heavily on water for its fertilisers, irrigation,crops and animals
E.g. 18% of world’s productive land is irrigated producing 40% of all food produced.
Without water, i would be impossible for farmers to grow crops and sell them, resulting in them making less income to support themselves= informal jobs
How human land use affect the shape of storm hydrographs
Shape of SHG depends on physical and human factors
Human=urbanisation
Flashy hydrograph ( steep rising limb, short lag time, high peak discharge)= impermeable surfaces, roofs, gutters, drains move water and sewage quickly to the river and really quickly- steep rising limb and high discharge
How does physical land use affect shape of storm hydrographs
Subdued hydrograph ( long lag time low peak)
Impermeable rocks= decrease percolation and allow the soils to become saturated, decrease infiltration and increase SRO
Longer lag time
Explain how land degradation and desertification can cause droughts
Human activity like over-farming can lead to over grazing, prevents regeneration of trees as samples are consumed and trampled on
Limit interception and evapotranspiration, meaning that the ground is no longer protected by the leaves’ canopy
Therefore, soil is vulnerable to the sun’s direct heat- dry, drought
E.g. 90% of Sahel farmers depend on viable saturated land to farm as it is their main source of income
Overfarming culture reduces land ability to retain moisture and supports agricultural production
Explain how deforestation an cause droughts
Without vegetation, there is reduced water uptake by plants and less moisture returning to the atmosphere, which means less evaporation and cloud formation, leading to less precipitation facilitating drier conditions e.g. amazon,126,000 hectares of trees are being logged as of 2025
Explain how urbanisation (land use) cause increasing flood risks
Changing greenfield sites to urban area with impermeable surfaces e.g. concrete
Reduce interception from trees due to the lack of canopy and facilitate faster SRO w short lag time, causing overland flows
E.g. rapid urban expansion /sprawl Houston USA experienced flooding after 2017 hurricane Harvey, as water can’t soak into the ground but moves quickly across the surface of the land
