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प्रश्न
Two types of aquatic organisms in a lake show specific growth patterns as shown below, in a brief period of time. The lake is adjacent to an agricultural land extensively supplied with fertilisers.
Answer the questions based on the facts given above:
(i) Name the organisms depicting the patterns A and B.
(ii) State the reason for the growth pattern seen in A.
(iii) Write the effects of the growth patterns seen above.
उत्तर
(a) A - Fish and clean water organisms depict dissolved oxygen; B - Decomposers depicts biochemical oxygen demand (BOD).
(b) As the sewage is decomposed, there is a gradual rise in the dissolved oxygen downstream with the reappearance of fish and other clean water organisms. This leads to the recovery of river from sewage water.
(c) Effects on aquatic life:
- (iv) It causes high mortality rate among aquatic animals.
- (v) The excessive nutrients facilitate algal growth causing algal bloom.
APPEARS IN
संबंधित प्रश्न
With the help of a flow-chart exhibit the events of eutrophication.
List the events that lead to biogas production from waste water whose BOD has been reduced significantly.
Write critical notes Biological magnification
Answer the following question:
While on a visit to a pond in the city-neighborhood, the visitors were delighted to find a large expanse of water covered with colorful algal mass.
As a student of biology, do you agree with their delight? Give reasons in support of your answer.
Biomagnification is caused mainly by ______.
Which one of the following diseases is not caused due to contamination of water?
Match the items in column I and column II and choose the correct option:
| Column I | Column II |
| A. UV | i. Biomagnification |
| B. Biodegradable Organic matter | ii. Eutrophication |
| C. DDT | iii. Snow blindness |
| D. Phosphates | iv. BOD |
The correct match is:
Match the following and choose the correct option.
| Column I | Column II |
| A. Environment Protection Act | i. 1974 |
| B. Air Prevention & Control of Pollution Act | ii. 1987 |
| C. Water Act | iii. 1986 |
| D. Amendment of Air Act to include noise as an air pollutant The correct matches is | iv. 1981 |
Match the following and choose the correct option.
| Column I | Column II |
| A. Environment Protection Act | i. 1974 |
| B. Air Prevention & Control of Pollution Act | ii. 1987 |
| C. Water Act | iii. 1986 |
| D. Amendment of Air Act to include noise as an air pollutant | iv. 1981 |
Match the following and choose the correct option.
| Column I | Column II |
| A. Environment Protection Act | i. 1974 |
| B. Air Prevention & Control of Pollution Act | ii. 1987 |
| C. Water Act | iii. 1986 |
| D. Amendment of Air Act to include noise as an air pollutant | iv. 1981 |
The correct matches is:
