The data obtained show that the SOM and microbial
biomass status in paddy soils was improved by
application of manure along with inorganic fertilizer.
It is therefore important that the traditional use of
manure should be strongly promoted in order to
maintain long-term soil productivity even where
inorganic fertilizer is being used to achieve high
yields. Not only will this improve the SOM status but
it will also reduce the rates of inorganic fertilizer
required, since nutrients will be released from the
manures. The incorporation of rice straw is another
important way of promoting SOM accumulation and
increasing the soil microbial biomass, hence the
importance of straw retention also needs to be
stressed. Recycling of animal manure and rice straw
in paddy agroecosystems can also help to solve
environmental and economic problems related to the
disposal of these waste materials.