Where does manure come from!

Introduction- You may have seen the gardener putting manure in the flower beds.
Do you know what it is and where it comes from?

Objective-To study the role of decomposers in the environment.

Materials required- Vegetable peels, rotten vegetables and fruits, dry leaves, cow dung etc.

Procedure- Dig one circular pit that is about one foot deep and one foot in diameter. Fill the pit with vegetable peels, rotten vegetables and fruits, dry leaves, cow dung till it is about three-fourths full. Fill the rest of the pit with soil and leave this pit undisturbed for two months. You can sprinkle water occasionally if the weather is too dry. Dig the pit after two months and observe.

Do you observe the peels, leaves etc. in the same shape and size as you had put them at the beginning of the experiment? Yes/No

If there is a change, describe what exactly do you find?

What term can you use for the process that brought the change- digestion, erosion, decomposition or precipitation?___________

Do you find any kind of living organisms in the pit-earthworms/insects/worms etc? Yes/No

Interpretation: The change in the vegetable peels, rotten vegetables and fruits, dry leaves, cow dung etc. into a homogenous mass, is brought about by micro organisms like bacteria and fungi that are present in the soil. Such microorganisms are called decomposers.

Re-enforcement - (i) Perform the same activity in summer and winter and note the difference in the extent of decomposition. Give reasons for your observations.
(ii) Collect some earthworms and put them in the pit with vegetable peels and cow dung. What difference do you observe in this case?
(iii) Add a few plastic bags with the vegetable peels and perform this experiment. Record your observations.