Ecosystem

The mass of living material at a trophic level at a particular time is called :

1. Net primary productivity
2. Standing state
3. Standing crop
4. Gross primary productivity

Vertical distribution of different species occupying different levels in a biotic community is known as :

1. Stratification
2. Pyramid
3. Divergence
4. Zonation

Secondary Succession takes place on/in :

1. Newly created pond
2. Newly cooled lava
3. Bare rock
4. Degraded forest

In an ecosystem the rate of production of organic matter during photosynthesis is termed as :

1. Secondary productivity
2. Net Productivity
3. Net primary productivity
4. Gross primary productivity

Match the following and select the correct option:

1. (a) (i), (b) (ii), (c) (iii), (d) (iv)
2. (a) (iii), (b) (ii), (c) (iv), (d) (i)
3. (a) (iv), (b) (i), (c) (iii), (d) (ii)
4. (a) (ii), (b) (i), (c) (iv), (d) (iii)

Given below is a simplified model of phosphorus cycling in a terrestrial ecosystem with four blanks (A-D). Identify the blanks. [figure]

1. A Detritus, B Rock minerals, C Producer, D Litter fall
2. A Litter fall, B Producers, C Rock minerals, D Detritus
3. A Rock minerals, B Detritus, C Litter fall, D Producers
4. A Producers, B Litter fall, C Rock minerals, D Detritus

If 20 J of energy is trapped at producer level, then how much energy will be available to peacock as food in the following chain? Plant mice snake peacock

1. 0.0002 J
2. 0.002 J
3. 0.2 J
4. 0.02 J

Natural reservoir of phosphorus is :

1. Fossils
2. Rock
3. Sea water
4. Animal bones

Secondary productivity is rate of formation of new organic matter by :

1. Parasite
2. Decomposer
3. Producer
4. Consumers

Which one of the following processes during decomposition is correctly described ?

1. Catabolism – Last step in the decomposition under fully anaerobic condition
2. Leaching – Water soluble inorganic nutrients rise to the top layers of soil
3. Fragmentation – Carried out by organisms such as earthworm
4. Humification – Leads to the accumulation of a dark coloured substance humus which undergoes microbial action at a very fast rate