03203nas|a2200409 i 4500 20260818134349.0 290500s1999 th uzm rtt 00| a1engxd .b11789761 AIT Thesis no. AS-99-04 Cárdenas, Germán Iván Soto Impact of inland shrimp culture on soil salinization and rice yield Bangkok : Asian Institute of Technology, 1999 60 leaves Thesis ; no. AS-99-04 A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Environment, Resources and Development Thesis (M.Sc.) - Asian Institute of Technology, 1999 An experiment was conducted for fifteen weeks at the Asian Institute of Technology in Thailand, to determine the depth distribution of salts over soil profile under low salinity irrigation regime and the impact of the produced salinity on rice yield. Supanburi-90 rice seedlings were planted in twelve experimental plots of 13m2 each (6.5 x 2m), with 5 plants in each hill. Rice plots were irrigated with water of 2ppt, 5ppt, 1 Oppt and Oppt as treatments. Water levels were maintained by refilling the plots twice a week. Salinity, conductivity, pH and cations of irrigation water and soil were monitored biweekly. Results show that 100% mortality of rice plants at 1 Oppt salinity during the fourth week of experiment. The lowest value for accumulated exchangeable Na+ in soil was in 30-60cm depth and the highest value in the top 5cm layer. A 2-week delay in flowering was observed in rice plants cultivated with 5ppt salinity compared with plants of control and 2ppt. There was found a significant (p<0.05) effect of all the treatments over the yields except for the ones treated with 2ppt and 5ppt salinity levels. The present experiment demonstrated that the major loss of exchangeable Na+ in irrigation water was in the top 30cm soil profile and the top 1 Ocm of the soil accumulated 50% of total cations. This experiment demonstrated that the rice yield had no significant difference using brackish water of 2ppt and 5ppt. Shrimp culture Soil salinization Crop yields Lin, C. K., Chairperson Hansen, G. K., Examination committee Preeda Pakpian, Examination Committee H.M. the King of Thailand Scholarship Program, Scholarship donor Asian Institute of Technology. Thesis ; no. AS-99-04 Full-Text http://203.159.5.9/ait-thesis/detail.php?q=B12628 .b11789761 mnait u 240330 0 000529 m a u 0 mnait mnarc 22 40 Barcode : 30050120695233 CREATED : 2013-06-09 RECORD # : i12740433 LPATRON : 1025183 LCHKIN : 2014-08-23 # RENEWALS : 0 # OVERDUE : 0 IUSE3 : 1 TOT CHKOUT : 1 TOT RENEW : 0 Barcode : 30050120359632 CREATED : 2016-09-06 RECORD # : i13028418 LPATRON : 0 LCHKIN : - # RENEWALS : 0 # OVERDUE : 0 IUSE3 : 0 TOT CHKOUT : 0 TOT RENEW : 0 58066 58066 0 0 0 0 MAIN MAIN mnait 2026-08-18 50.00 0 AIT Thesis no. AS-99-04 30050120695233 2026-08-18 13:43:49 3 2026-08-18 22 0 0 0 0 MAIN MAIN mnarc 2026-08-18 0 AIT Thesis no. AS-99-04 30050120359632 2026-08-18 13:43:49 1 2026-08-18 40