Introduction to soils 

• What is soil?
  Soils is the living skin of the Earth, overlying bedrock.
     
• Functions of soil
  Soil is our life support system. Soils provide anchorage for roots, hold water and nutrients. Soils are home to myriad micro-organisms that fix nitrogen and decompose organic matter, and armies of microscopic animals as well as earthworms and termites. We build on soil as well as with it and in it  more ...
   
• How do soils form?
  Soils are made from weathered rock - the parent material - by the action of climate and living organisms, usually over long periods of time. Living organisms create the architecture of soil and add organic matter that distinguish soil from rock  more ...
       
• World soil distribution
  Climate plays an important role in soil formation so soils differ widely from one climatic zone to another. In actively growing mountains, where the soils are young, and in cold and dry regions, soils are thin and stony compared with older landscapes and warm wet regions. Soil survey, or soil mapping, is the process of determining the soil types or other properties of the soil cover over a landscape, and mapping them for others to understand and use.
  (See virtual tour of the Major Soils of the World and the World Soil Museum).
    
• What to do and not to do with soils
  Soil is always at risk from degradation by erosion, salinity, contamination and other results of mismanagement. Some 17% of the land surface has already been strongly degraded and the affected area is still growing. This eventhough there is a  wealth of know-how related to land management, improvement of soil fertility, and protection of soil resources.
     
• World Reference Base for Soil Resources 
  Main properties, distribution and pictures of the reference groups of the World Reference Base for Soil Resources (2006).  The procedure for soil description and collecting field data necessary for classification according to WRB is described in the Guidelines for Soil Description.   more ...
     
• Soil image catalogue - A on-line catalogue of soil images, plus metadata, prepared by the Joint Research Centre, IES, SOIL Action in collaboration with ISRIC - World Soil Information 
   
• ISRIC - World Soil Information Database - An on-line catalogue with simple and advanced search facilities and links to over 4000 (zoomable) maps, some 2050 full text reports from ISRIC's WDC for Soil holdings and much more ... 
  
   
• Glossary of soil science terms