Productivity is the rate of production of biomass expressed in terms of :
i.
ii.
iii.
iv.
1. | ii | 2. | iii |
3. | ii and iv | 4. | i and iii |
In an ecosystem, the rate of production of organic matter during photosynthesis is called as its:
1. | Gross Primary productivity |
2. | Net Primary productivity |
3. | Secondary productivity |
4. | Non productivity |
Net primary productivity is the gross primary productivity minus:
1. | that which is consumed by herbivores |
2. | that which is consumed by the producer in metabolism |
3. | secondary productivity |
4. | loss due to mortality |
Secondary productivity in an ecosystem can be defined as:
1. | The amount of chemical energy, typically expressed as carbon biomass, that primary producers create in a given length of time. |
2. | The rate at which all the autotrophs in an ecosystem produce net useful chemical energy. |
3. | The rate of formation of new organic matter by consumers. |
4. | The amount of energy released by the action of detritivores and decomposers in an ecosystem. |
The annual net primary productivity of whole biosphere is approximately:
1. | 25 billion tons | 2. | 55 billion tons |
3. | 70 billion tons | 4. | 170 billion tons |
Statement I: | Tropical land areas have the highest rates of production. |
Statement II: | Oceans have low productivity. |
What percentage of photosynthetic active radiation is captured by plants?
1. | 1 – 5 | 2. | 2 – 10 |
3. | 50 | 4. | 90 |
On the land, almost all primary production is performed by:
1. | Phytoplanktons | 2. | Algae |
3. | Mosses and Liverworts | 4. | Vascular plants |
Suppose in an area, the energy present in total incident sunlight falling on primary producers is 10,00,000 J and about 10,000 J is converted by them into biomass. What percent of PAR have the primary producers been able to convert?
1. | 1 % | 2. | 2 % |
3. | 10 % | 4. | 20 % |