ORGANIC farming has gained ground worldwide and has ……...expanded in recent years due to environmental, economic, and social concerns. In Egypt, up to 2.23 % of the agricultural area is managed organically. The transition from conventional to organic farming is accompanied by changes in an array of soil properties and processes that affect soil fertility. These changes in soil properties under Egyptian condition are not well documented. Therefore, the present study was carried out to study the comparative effects of organic and conventional farming systems on some soil chemical indicators under Egyptian condition.
Surface soil samples (0-30 cm) were collected from eight field pairs (organic field and its conventional counterpart) to represent Organic farms in three locations (Fayoum (Tubhar village), Bilbeis city (SEKEM organic farm) and Salhyia City). The organic fields were in organic practice for 4, 6, and 10 years (Fayoum samples), 20 and 30 years (Sharkyia samples), 8, 10 and 12 years (Ismailia samples) since certification. The studied soil chemical indicators include soil organic carbon, T-N, pH, EC, CEC, exchangeable cations, and available N, P, K, Fe, Mn, Zn and Cu.
Soil organic carbon, T-N, CEC, and available N, P, K, Fe, and Mn were significantly higher in the organic system than in the conventional system. Also, organically managed soils showed significantly better soil nutritional status regardless the periods of organic farming practice. On the other hand, soil pH, EC, available Cu and Zn were higher in the conventional system than in the organic system.