The second stage of hydrosere is occupied by plants like :   
1. Azolla
2.Typha
3.Salix
4. Vallisneria

Natural reservoir of phosphorus is :    
1. Animal bones
2. Rock
3. Fossils
4.Sea water

Secondary productivity is rate of formation of new organic matter by:  
1. Parasite
2. Consumer
3. Decomposer
4. Producer

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

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

Options :

Match the following and select the correct option :  
(a) Earthworm                       (i) Pioneer species
(b) Succession                      (ii) Detrivore
(c) Ecosystem service           (iii) Natality
(d) Population growth            (iv) Pollination

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

Vertical distribution of different species occupying different levels in a biotic community is known as:                                                                                                       
1. Stratification
2. Zonation
3. Pyramid
4. Divergence

The mass of living material at a trophic level at a particular time is called:      
1. Standing state
2. Net primary productivity
3. Standing crop
4. Gross primary productivity

In an ecosystem the rate of production of organic matter during photosynthesis is termed as : 
1. Gross primary productivity
2. Secondary productivity
3. Net productivity
4. Net primary productivity

Secondary Succession takes place on/in :  
1. Degraded forest
2. Newly created pond
3. Newly cooled lava
4. Bare rock