Stratification of an ecosystem means:

1.	Vertical distribution of different species occupying different levels
2.	Vertical distribution of different species occupying the same levels
3.	Horizontal distribution of different species occupying different levels
4.	Horizontal distribution of different species occupying the same levels

In an ecosystem, the rate of production of organic matter during photosynthesis is called as its:

The rate of formation of new organic matter by consumers in an ecosystem is known as:

The annual net primary productivity of whole biosphere is approximately:

By process of leaching during decomposition of detritus, water soluble :

During decomposition of detritus, the step that is performed by bacteria and fungi includes:
1. Catabolism only
2. Catabolism and fragmentation
3. Leaching and catabolism
4. Fragmentation, Leaching and Catabolism

The three steps of decomposition occur:
1. sequentially, with catabolism being the last step.
2. sequentially, with leaching being the last step.
3. simultaneously.
4. sequentially, but not in a particular order.

Humus:
1. Is easily broken down by microbes
2. Undergoes decomposition rapidly
3. Serves as a reservoir of nutrients
4. Yields organic nutrients on mineralization

Decomposition of detritus is rapid when:
1. It is rich in lignin and chitin
2. Ambient temperature is low
3. Environment favours anaerobiosis
4. It predominantly contains nitrogen and sugars

What percentage of photosynthetic active radiation is captured by plants?