Question

In a village, farmers started cultivating crops all around a lake which was always filled with water. They added lot of materials W to the soil in their fields to increase the yield of crops. Soon they found that the whole surface of water in the lake was covered with a green layer made up of tiny organisms X. After some time, the fish present in the lake started dying in large numbers because they could not get sufficient Y due to a process Z which had occurred in lake water and drained out all the Y present in the water of lake.
(a) What do you think materials W are?
(b) Name (i) X, and (ii) Y.
(c) What is the process Z known as?
(d) What happens during the process Z which uses up all the Y present in lake water?
(e) What does this example tell us about the use of materials like W?

Answer 1

Answer:

material w maybe wastes or fungal diseases caused

Answer 2

Answer:

(a) The materials (W) are fertilizers.  

(b) The name (i) X is algae and (ii) Y is oxygen.

(c) The process Z known as eutrophication.

(d) During the process Z (eutrophication) all the Y (oxygen) present in lake water is used up which leads to depletion of the oxygen in the water.

(e) The over usage of materials like W causes harm to the environment.

Explanation:

• The fertilizers are chemical materials which is produced naturally or industrially. This is used to infuse growth of the plants by supplying certain nutrients to the plants.
• Algae belongs to kingdom Plantae which lives in water and moist lands. There are various colors in algae. These undergo both sexual and asexual reproduction.
• The oxygen is a vital element present in the environment. This is used by all the animals to respire and used in the process of water formation.
• Eutrophication is the process of growth of excess amount of algae on the surface of the water body. This algae uses all the oxygen present under the water for growth and development which depletes the oxygen for the aquatic species present in that water body.

You can get all the answers of Chapter 6 in below link:

https://brainly.in/question/13831528