Question

B Here is an extract of are report on water situation in the state of Punjab.Analyse it in a

paragraph:

The groundwater is continuously declining in 85% areas of the state.Nitrate presence

in water has gone up by 10times in the past four decades.In 1972 water had

0.5mg/litre of nitrate.As of now,it has increased to 5mg/litre.It may reach

10mg/litre in the nextb20years,due to excessive use of insecticides and pesticides,

making it unfi tfor human and animal consumption​

Answer 1

Answer:

Under aerobic conditions, nitrate can percolate in relatively large quantities into the

aquifer when there is no growing plant material to take up the nitrate and when the net

movement of soil water is downward to the aquifer. Degradation or denitrification

occurs only to a small extent in the soil and in the rocks forming the aquifer. Under

anaerobic conditions, nitrate may be denitrified or degraded almost completely to

nitrogen. The presence of high or low water tables, the amount of rainwater, the

presence of other organic material and other physicochemical properties are also

important in determining the fate of nitrate in soil (van Duijvenboden & Loch, 1983;

Mesinga, Speijers & Meulenbelt, 2003; Fewtrell, 2004; Dubrovsky & Hamilton,

2010). In surface water, nitrification and denitrification may also occur, depending on

the temperature and the pH. The uptake of nitrate by plants, however, is responsible

for most of the nitrate reduction in surface water.