Which one of the following factors does not affect the distribution of groundwater?
- (a)Amount of precipitation
- (b)Rate of evaporation
- (c)Ability of the ground surface to allow water to infiltrate into the groundwater system
- (d)Distance from the sea
Correct — D, Distance from the sea. Groundwater is stored underground, so its distribution is governed by how much water arrives (precipitation), how much is lost back to the air (evaporation) and how easily water can soak in (the infiltration capacity or permeability of the surface). How far a place lies from the sea does not, by itself, control how much water percolates and is held below ground, so that is the factor which does not affect groundwater distribution.
- (a)Amount of precipitation — Precipitation is the main source that recharges aquifers, so it directly affects how much groundwater is available — it does influence distribution.
- (b)Rate of evaporation — High evaporation removes water before it can percolate downward, reducing recharge, so it genuinely affects groundwater distribution.
- (c)Ability of the ground surface to allow water to infiltrate into the groundwater system — Infiltration capacity (permeability) decides how much surface water actually reaches the water table, so it is a key control on groundwater — not the exception.
Groundwater occurs in the pore spaces and fractures of rocks below the water table. Whether an area is rich or poor in groundwater depends on the water budget of that place — recharge from precipitation, losses through evaporation, and how readily the surface lets water infiltrate (its permeability, slope and vegetation cover).
The examiner lists three genuine hydrological controls and one geographic label that sounds relevant. Distance from the sea affects rainfall and salinity in coastal strips, but it is not itself a control on how groundwater is distributed, so it is the odd one out.
- Precipitation is the principal source of natural groundwater recharge.
- Evaporation returns water to the atmosphere before it can infiltrate, reducing recharge.
- The permeability and infiltration capacity of the surface determine how much water reaches the water table.
- Slope, vegetation and rock porosity also shape groundwater storage; mere distance from the sea does not.
Three genuine hydrological controls plus one geographic label that does not govern groundwater — so the answer is (d).
- Assuming 'distance from the sea' matters because coastal areas can face saline groundwater — that is water quality, not distribution.
- Overlooking evaporation as a real loss term in the groundwater budget.
Asked as 'which does NOT affect' — separate the true hydrological controls from a plausible-sounding geographic label.
On the planet Earth, most of the freshwater exists as ice caps and glaciers. Out of the remaining freshwater, the largest proportion
- (a) is found in the atmosphere as moisture and clouds
- (b) is found in freshwater lakes and rivers
- (c) exists as groundwater
- (d) exists as soil moisture
Answer(c) exists as groundwater
Same subject — groundwater in the hydrological cycle. That UPSC item shows groundwater holds the largest share of liquid freshwater; this NDA item tests what controls where that groundwater is distributed.
Which one of the following is NOT a cause of depletion in groundwater?
- (a) Afforestation
- (b) Loss of forests
- (c) Excessive pumping of groundwater
- (d) Construction of large scale concrete buildings
Answer(a) Afforestation
Same theme — the controls on groundwater. That NDA item asks what does NOT deplete groundwater (afforestation actually aids recharge); this one asks which factor does NOT affect its distribution.
- practice — not a real PYQ
Which one of the following is the principal natural source of groundwater recharge?
- (a)Evaporation
- (b)Precipitation
- (c)Ocean currents
- (d)Wind
Answer(b) Precipitation — rainfall and snowmelt percolate down to recharge aquifers.
- practice — not a real PYQ
The upper surface of the zone of saturation of groundwater is called the
- (a)Water table
- (b)Aquiclude
- (c)Playa
- (d)Watershed
Answer(a) Water table — the top of the saturated zone.