Plant material is not the only source of C entering the soil. Livestock-derived C such as manures and abattoir waste and human-derived sewage sludge and municipal green waste are important components of recycling but which can have profound and deleterious effects on soil quality and health, thereby impacting on soil function. To predict better the effects of these C inputs on soil function it is essential that we fully understand the interactions between its composition, the soil's physicochemical environment, microbial activity and hydrology. We will make a more detailed biochemical and physical analysis of particularly livestock-derived C using conventional proximate analysis, rapid spectral analysis by NIRS, physical fractionation and laser sizing. These methods will be used to determine the relationship between particle size and substrate composition and relative mineralisation rates of N and C as a function of soil depth and relative soil microbial activity. The rate of Infiltration of livestock-derived C into soil is a key to controlling gaseous emissions, the fate of water soluble nutrients and the survival and potential mobilisation of pathogens. We will establish the relationship between water-filled pore space content and rates of infiltration of these C inputs with a range of solid contents, their interaction with infiltration, rainfall intensity and nutrient/pathogen mobilisation and thus develop a descriptive model for infiltration.