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| | What is salinization? | | | | It is a process of enrichment of a soil in soluble salts which results in the formation of a salt-affected soil. | | | | How is salinization a problem? | | | Salinization causes: - an increase in osmotic pressure which makes water mobilization more difficult for plants;
- toxicity of certain ions to plants (Cl-, Na+, etc.);
- degradation of the soil (changes in structural state, reduction of hydraulic conductivity, etc.).
| | | | Is it a serious problem today? | | | | Globally The world is losing, on average, 10 hectares of land suitable for cultivation every minute, of which 3 hectares is as a result of salinization (equivalent to 1.5 Mha per year) [Kovda, 1983]. Today it is estimated that almost 400 Mha are affected by salinization [Bot, Nachtergaele and Young, 2000]. In Africa... almost 40 Mha are affected by salinization, around 2% of the total surface area. In the Near East... almost 92 Mha are affected by salinization, around 5% of the total surface area. Access to specific data for some African countires and the Near East... | | | | What are the causes of land salinization? | | | | 80% of salt-affected land has a natural origin. Thus the use of the term “primary” salinization, due to salts formed by weathering of rocks or natural external inputs. 20% of salt-affected land, around 15 Mha on the continent of Africa alone, have a "man-made" origin. Thus the use of the term "secondary" salinization, introduced by human activity linked to agricultural practices, and in particular to irrigation. | | | | |
 | | | | | | | Headline | Call for Contribution - GRID Magazine Issue 24 | | Text | The new IPTRID's magazine issue will be published in teh five official languages of FAO during the 1st quarter of 2006. | | Keywords | GRID; IPTRID; CALL; CONTRIBUTION; PAPER; PUBLICATION | | Picture to upload |  | | File Location |  GRID Issue 24 (en) GRID Numéro 24 (fr) | | Author(s) / Editor(s) | Secretariat de l'IPTRID | | Series Title | IPTRID Secretariat | | Publication Date | 01 September 2005 | |
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