Use of nitrogen from manure

Abstract

The potential for denitrification is enhanced because the organic matter in the manure furnishes energy for microbial activity. This chapter points out the many management variables determining the value of manure to crops. It discusses the total N in manures produced in the United States, N balance sheets for animal production systems, watersheds, farms, and fields, management factors that reduce N losses, and manure management in the future. Most of the farming is devoted to corn, hay, small grains, and pasture for 6800 dairy cows in the watershed. Manure is a source of all plant nutrients and it is a soil conditioner. In many cases, the manure was managed such that NH3 was volatilized before incorporation into the soil and/ or the manure was applied in advance of active crop uptake; hence, the leaching and denitrification losses of the inorganic N were excessive.