# Synoptic Revision Edexcel - Decomposition watch

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1. Could anyone explain about the different types of decomposition? Eg. differences in land/water, carbon + nitrogen.

And I don't understand what organic means..? My book says sewage contain domestic and industrial waste predominantly organic.. yet I thought the bacteria broke down sewage into ammonia (not carbon-related compounds?)
2. well there is only one type of decomposition i learnt in unit 3...its just the normal decompsition...where organic matter(substances from that were once living or are hydrocarbons) are broken down to inorganic substances such as CO2 H2O and so on...

well not all bacteria can break down nitrates to ammonia there are specific denitrifying bacteria which can do this such as pseudomonas denitrificans
i think you got confused between the carbon cycle and the nitrogen cycle....
try being more specific in the question...i cant really understand it...

hope i helped...
3. (Original post by Sky Twilight)
Could anyone explain about the different types of decomposition? Eg. differences in land/water, carbon + nitrogen.
The only one I recall is the decomposition of dead organic matter to ammonia, CO2 and H2O. Maybe you mean different processes of the nitrogen and carbon cycle?

And I don't understand what organic means..? My book says sewage contain domestic and industrial waste predominantly organic..
Organic material is decayable material from living organisms. It normally contains carbon.

yet I thought the bacteria broke down sewage into ammonia (not carbon-related compounds?)
I think you mean nitrogen fixation? Nitrogen fixation by Rhizobium bacteria turns N2 to nitrate, ammonia or ammonium ions. But that is in plant roots.
4. I thought there were 2 types of decomposition.

Eg breakdown of organic matter (which are also nitrogen containing compounds) into ammonia = decomposition/ammonification, by putrefying bacteria
and the breakdown of organic matter into CO2, water in soil by saprobionts

Sorry if I'm confusing =/

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