The rate of decomposition of detritus is controlled by the chemical nature of detritus and a number of climatic factors given below.
Chemical nature of detritus: The decomposition of detritus is slow if it contains lignin, chitin, tannins (phenolics) and cellulose. It is rapid if detritus possesses more nitrogenous compounds (like proteins, nucleic acids) and water-soluble reserve carbohydrates or sugars.
The temperature above 25oC favours the growth of microorganisms.
Soil moisture is the most important climatic factors that regulate decomposition through their effects on the activities of soil microbes.
Aeration: It is required for the activity of decomposers and detritivores. Reduced aeration will slow down the process of decomposition.
Soil pH: The growth of microbes is low in acidic soils as compared to basic soils.
So, the detritus rich in lignin and chitin will undergo slow decomposition.