User:Pauline Samain/Brouillon

= Clay pot irrigation = Clay pot irrigation is a subsurface irrigation system, water efficient and very well adapted to small farms in arid zones. This system consists of low fired unglazed clay pots buried to the neck and filled with water. The porous walls of the pots will allow water infiltration into the soil and to the roots of the plants around.

The clay pot irrigation is also know as : olla or oya (name coming from the spanish word for pot), pitcher farming, pitcher irrigation, porous or buried clay pot.

This very ancient system, mostly unknow today, is being rediscovered by scientists since the years 1960's.

Clay pot irrigation has many advantages : it is simple and cheap, it allows important water savings (from 50 to 70%), it gives a regular irrigation adapted to plant needs, and it lessens the problem of weed growth. However, it has also some disadvantages: difficulty of installation, low mobility, fragility of the material.

History
The agronomist Fan Sheng-Chih Shu (氾胜之书), is a document written in China during the first century BCE, describes the use of buried, unglazed clay pots filled with water as a means of irrigation. The researcher T.M. Stein, as for him, considers that clay pot system may come from North Africa and Iran. Others authors from Latin America think that it was originated by the roman empire.