Agriculture 2 Pollution and Degradation 2 Soil Chemistry and Mineralogy 2 Soil Fertility 2 Soil Surveys and Land Evaluation Soil degradation 2 Soil fertility 2 Sustainability 2 Agricultural development 1 Agricultural soils 1 Biodiversity 1 Biomass 1 Case studies 1 Cropping systems 1 Demography 1 Erosion 1 Erosion: Soil and Water Conservation 1 Field Crops, (New March 2000) 1 Forest plantations 1 Human Wastes and Refuse 1 Industrial Wastes and Effluents 1 Industrial wastes 1 Land Resources 1 Land management 1 Land use 1 Land use planning 1 Microbial flora 1 Microorganisms 1 Nitrogen 1 Nontarget effects 1