Question

What causes the different amounts of nitrate concentration measured at different depths of a lake?

What causes the different amounts of phosphate concentration measured at different depths of a lake?

Water Sample Depth Nitrate (mg/L) Phosphate (mg/L) 0-1 m 1m 7m 1.4 7.25 0.18 0.08 0.15 1.27 8m 15.5m

Answer 1

1-The varying Nitrate concentration at different depths of a lake

Nitrate is one of the forms of nitrogen. Nitrates are produced as an excretory product by the ammonotelic organisms and readily get dissolved in the water. They are also used as potent fertilizers by farmers, these fertilizers are highly soluble in nature hence they can easily penetrate the soil and enter water bodies, other sources of nitrate are chemical effluents drained by the industries, human activity, etc. The concentration of nitrate varies widely with respect to distance from the earth's surface. Shallow water region contains a higher concentration of nitrate then compared to the deepwater region. The concentration of NO3 in water bodies depends on various factors:-

1. Dissolved oxygen concentration.
2. The flow of groundwater.
3. Use of chemical fertilizers.
4. Irrigation, etc.

Affect of nitrate on water bodies:-

1-The presence of excess nitrate in water bodies can act as a good source of nourishment for the algal species and will lead to excessive growth.

2- Change in dissolved oxygen concentration de to the production of oxygen by algal species during day time.

3- Eutrophication of the water body due to the presence of excess nutrient in the water,

CONCENTRATION OF PHOSPHATE AT DIFFERENT DEPTH OF LAKE

The concentration of phosphate in water bodies usually decreases with an increase in the depth and height of the lake. There are different sources from where phosphates are introduced into the water bodies are soil, rocks, runway fertilizers, cleaning agents, and industrial effluents. Excess amounts of phosphate in water bodies can have a similar effect as of nitrate and can lead to a decrease in oxygen concentration and eutrophication of the water bodies.