The breakdown of detritus into smaller particles by earthworm is a process called 
1. Humification
2. Fragmentation
3. Mineralisation
4. Catabolism

Which one of the following is not a gaseous biogeochemical cycle in ecosystem ?  
1. Sulphur cycle
2. Phosphorus cycle
3. Nitrogen cycle
4. Carbon cycle

Identify the possible link "A" in the following food chain :    
Plant → insect - frog → "A" → Eagle
1. Rabbit
2. WoIf
3. Cobra
4. Parrot

Given below is an imaginary pyramid of numbers. What could be one of the possibilities about certain organisms at some of the different levels?                                                 

Which one of the following is not a functional unit of an ecosystem 
1. Energy flow
2. Decomposition
3. Productivity
4. Stratification

The upright pyramid of number is absent in      
1. Pond
2. Forest
3. Lake
4. Grassland

Identify the likely organisms (a), (b), (c) and (d) in the food web shown below:     

Options

The rate of formation of new organic matter by rabbits in grassland is called:

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