Soil organic matter Soil Chemistry and Mineralogy 8 Soil fertility 7 Soil Biology 6 Soil Fertility 5 Nutrient uptake 4 Plant Nutrition 4 Plant nutrition 4 Agroforestry 3 Nitrogen 3 Nutrient availability 3 Phosphorus 3 Soil chemistry 3 Soil fauna 3 Soil flora 3 Soil management 3 Agricultural soils 2 Agroforestry and Multipurpose Trees: Community, Farm and Social Forestry 2 Biodiversity 2 Biofertilizers 2 Biological activity in soil 2 Biomass 2 Crop production 2 Crops 2 Cycling 2 Decomposition 2 Ecosystems 2 Erosion 2 Erosion: Soil and Water Conservation 2 Fertilizers and other Amendments 2