Q. No.In the equation GPP - R = NPP,
R represents:
| 1. | Environment factor |
| 2. | Respiration losses |
| 3. | Radiant energy |
| 4. | Retardation factor |
Subtopic: Ecosystem Productivity |
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Level 1: 80%+
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Consider the following statements regarding primary productivity in an ecosystem:
Which of the above statements is/are correct?
1. (a) only
2. (b) only
3. Both (a) and (b)
4. Neither (a) nor (b)
| (a) | Gross Primary Productivity (GPP) is the total rate of organic matter production through photosynthesis in plants. |
| (b) | Net Primary Productivity (NPP) is obtained by subtracting respiration losses (R) from GPP, representing the energy available to the next trophic level. |
Which of the above statements is/are correct?
1. (a) only
2. (b) only
3. Both (a) and (b)
4. Neither (a) nor (b)
Subtopic: Ecosystem Productivity |
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Level 1: 80%+
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What does secondary productivity refer to in an ecosystem?
| 1. | The rate of formation of new organic matter by producers |
| 2. | The rate of formation of new organic matter by consumers |
| 3. | The total amount of organic matter present in an ecosystem |
| 4. | The energy lost as heat during metabolic activities |
Subtopic: Ecosystem Productivity |
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If Gross Primary Productivity (GPP) of an ecosystem is 2500 kcal m⁻² yr⁻¹ and the respiration loss is 1800 kcal m⁻² yr⁻¹, then Net Primary Productivity (NPP) is:
| 1. | 4300 | 2. | 2500 |
| 3. | 700 | 4. | 1800 |
Subtopic: Ecosystem Productivity |
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Primary productivity in an ecosystem mainly depends on the:
| 1. | colour of the soil and the speed of wind in the area. |
| 2. | plant species present, environmental conditions, nutrient supply, and photosynthetic capacity. |
| 3. | total number of herbivore species present in the food web. |
| 4. | pressure exerted by decomposers on nutrient cycling. |
Subtopic: Ecosystem Productivity |
92%
Level 1: 80%+
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Productivity in an ecosystem at the producer level depends upon
| 1. | Availability of nutrients in the soil |
| 2. | Photosynthetic capacity of plants |
| 3. | Variety of environmental factors |
| 4. | All of these |
Subtopic: Ecosystem Productivity |
95%
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Consider the given two statements:
| Assertion (A): | Ocean ecosystems have lower productivity per unit area compared to terrestrial ecosystems. |
| Reason (R): | Nutrient availability and light penetration are limited in many ocean areas, restricting photosynthetic activity. |
| 1. | Both (A) and (R) are True and (R) explains (A). |
| 2. | Both (A) and (R) are True but (R) does not explain (A). |
| 3. | (A) is True but (R) is False. |
| 4. | (A) is False but (R) is True. |
Subtopic: Ecosystem Productivity |
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Net primary productivity of whole biosphere is about:
1. 55 billion tons per month
2. 55 billion tons per year
3. 170 billion tons per month
4. 170 billion tons per year
1. 55 billion tons per month
2. 55 billion tons per year
3. 170 billion tons per month
4. 170 billion tons per year
Subtopic: Ecosystem Productivity |
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The annual net primary productivity of the whole biosphere is approximately 170 billion tons (dry weight) of organic matter. Of this, the productivity of the oceans is:
1. 55 billion tons.
2. 70 billion tons.
3. 100 billion tons.
4. 120 billion tons.
1. 55 billion tons.
2. 70 billion tons.
3. 100 billion tons.
4. 120 billion tons.
Subtopic: Ecosystem Productivity |
89%
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The rate of formation of new organic matter by rabbit in grassland is called
1. net productivity
2. secondary productivity
3. net primary productivity
4. gross primary productivity
Subtopic: Ecosystem Productivity |
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