Biological management of nutrient supply to plants is intrinsically more complex than the provision of nutrients as inorganic fertilizers. We need to know whether the nutrients released are retained or lost from the system, whether rates of decomposition can be manipulated to improve nutrient use efficiency, and how the various fractions of plant residues translate into pools of organic matter in soil. Only then can predictive models for nutrient release, plant uptake and soil organic matter dynamics be truly tested and validated. This book brings together contemporary ideas on the characterization and manipulation of plant quality and especially its role in soil organic matter formation and nutrient cycling. It contains work from the leading workers in both temperate and tropical systems. There are also contributions describing work outside decomposition in soil ecosystems, such as the work of plant biochemists and animal nutritionists, as research in these areas has provided many ideas and concepts used in plant quality analysis. A wide range of topics is covered from investigations at the molecular level through to management options for farmers in relation to optimising biological management of crop residues. The work presented in this volume is valuable to all those researching and managing the supply of nutrients to plants. It is important reading for soil scientists, plant physiologists and crop scientists.