Online Soil Information

Global Soil Biodiversity Atlas

http://esdac.jrc.ec.europa.eu/public_path/JRC_global_soilbio_atlas_online.pdf

Simple Soil, Water and Plant Testing Techniques for Soil Resource Management

ftp://ftp.fao.org/agl/agll/docs/misc28.pdf

Soil management: compost production and use in tropical and subtropical environments

http://www.fao.org/3/a-s8930e.pdf

Procedures for Soil Analysis

http://www.isric.org/isric/webdocs/docs/ISRIC_TechPap09_2002.pdf

Assessment of Soil Nutrient Balance

http://www.fao.org/3/a-y5066e.pdf

Soil Survey Field and Laboratory Methods Manual

http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb1244466.pdf

Field Book for Describing and Sampling Soils

http://www.nrcs.usda.gov/wps/PA_NRCSConsumption/download?cid=nrcs142p2_052523&ext=pdf

Kellogg Soil Survey Laboratory Methods Manual

http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb1253871.pdf

Soil Survey Manual

http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_050993.pdf

Illustrated Guide to Soil Taxonomy

http://www.nrcs.usda.gov/wps/PA_NRCSConsumption/download?cid=stelprdb1247203&ext=pdf

Keys to Soil Taxonomy

http://www.nrcs.usda.gov/wps/PA_NRCSConsumption/download?cid=stelprdb1252094&ext=pdf