Question

what are the harmful effects of eutrophication?


Mention the three steps used to purify water​

Answer 1

1.Harmfull effects of eutrophication

The main effects caused by eutrophication can be summarized as follows

1. Species diversity decreases and the dominant biota changes

2. Plant and animal biomass increase

3. Turbidity increases

4. Rate of sedimentation increases, shortening the lifespan of the lake

5. Anoxic conditions may develop

Because of the high concentration of organisms in a eutrophic system, there is often a lot of competition for resources and predator pressure. This high degree of competition and the sometimes-high chemical or physical stress make high the struggle for survival in eutrophic systems. As a result, the diversity of organisms is lower in eutrophic than in oligotrophic systems.

2.three steps used of purity water

1.Boiling. Bring the water to a rolling boil for 3-5 minutes. Let cool before drinking.

2.Disinfect. You can use household liquid bleach (regular household bleach contains 5.25% sodium hypochlorite) to kill microorganisms. ...

3.Distillation. Fill a pot halfway with water.

Answer 2

Answer:

harmful effects of euthophication

Primarily, the adverse effects of eutrophication on aquatic bodies include a decrease in biodiversity, increase in toxicity of the water body, and change in species dominance. Some other important effects of this process are listed below.

• Phytoplanktons grow much faster in such situations. These phytoplankton species are toxic and are inedible.

• Gelatinous zooplankton blooms fast in these waters.

• Increased biomass of epiphytic and benthic algae can be observed in eutrophic waters.

• Significant changes arise in the species composition of macrophytes and the biomass.

• The water loses its transparency and develops a bad smell and colour. The treatment of this water becomes difficult.

• Depletion of dissolved oxygen in the water body.

• Frequent fish kill incidents occur and many desirable fish species are removed from the water body.

• The populations of shellfish and harvestable fish are lowered.

• The aesthetic value of the water body diminishes significantly.

Explanation:

mention the three steps used to purify water

1. Aeration:

Raw water is first collected in large aeration tank and the water is aerated by bubbling compressed air through perforated pipes.

Aeration removes bad odors and CO2. It also removes metal such as iron, manganese by precipitating then as their respective hydroxides.

2. Storage or settling:

Aerated water is then placed in settling tank and stored for 10-14 days.

During storage about 90% of suspended solids settle down within 24 hrs and the water becomes clear.

Certain heavier toxic chemicals also settle down during storage.

Similarly pathogenic bacteria gradually die and bacterial count decreases by 90% in first in first 5-7 days of storage.

During storage organic matter present in water is oxidized by microorganisms. Similarly NH3 present is oxidized into nitrate by microorganisms during storage.

3. Coagulation:

Water from storage tank is then placed in coagulation tank and then some precipitating agents such as alum, lime etc are added in water and mixed.

These precipitating agents form precipitate of Al(OH)3 when dissolved in water.

Suspended solids absorbs on the surface of precipitate, so gradually mass of precipitate becomes heavier and finally settle down.

This technique is used to remove very light suspended solids that do not settle by themselves during storage. Furthermore, if negatively charged colloidal impurities are present, they are neutralized by Al+++ ions and settle down.