Alterations in Soil Chemical Properties Induced by Continuous Rice Cultivation: A Study on the Arid Nile Delta Soils of Egypt

作者：El Shahway Ashraf Samy; Mahmoud Mahmoud M A; Udeigwe Theophilus K^*

来源：Land Degradation & Development, 2016, 27(2): 231-238.

DOI：10.1002/ldr.2409

• calcium carbonate
• exchangeable
• soluble cations
• paddy soil
• flooding
• North Africa
• salinity

Changes in soil chemical properties resulting from continuous rice (Oryza sativa) cultivation on the Nile Delta soils of Egypt were examined. The eight soil profiles characterized for this study were designated as 0 (crop rotation without rice), 1 (crop rotation with rice after every 2years), and 2, 3, 4, 5, 6, and 7 representing continuous rice cultivation for 2, 4, 8, 12, 15, and 20years, respectively. Sampling was conducted at 0-20, 20-40, 40-60, and 60-80cm depths for each profile and samples analyzed for a suite of chemical properties. Soil pH, salinity indicators [electrical conductivity (EC), and exchangeable sodium percentage (ESP)], as well as soluble and exchangeable cations and anions such as chloride and sulfate, all tended to decrease with years of continuous rice cultivation, with a number of significant (p<005) differences observed. Cation exchange capacity (CEC) increased with years of continuous rice cultivation, with a 12% increase observed between 2- and 20-year continuous rice cultivation systems. Principal component analysis conducted on soil properties within the continuous rice cultivation systems (profiles 2-7) revealed two possible components, namely F1 (pH, EC, ESP, and soluble Na+, Mg2+, K+, Cl-, and SO4-2) and F2 (clay, organic matter, and CEC), which could be broadly associated to soil salinity and soil fertility, respectively. Findings suggested possible alterations in soil chemical properties by continuous rice cultivation practices on these Nile Delta soils of Egypt, Africa.

• 出版日期2016-2