000			03203nas|a2200409 i 4500
005			20260818134349.0
008			290500s1999 th uzm rtt 00| a1engxd
035			_a.b11789761
099		9	_aAIT Thesis no. AS-99-04
100	1		_aCárdenas, Germán Iván Soto
245	1	0	_aImpact of inland shrimp culture on soil salinization and rice yield
260			_aBangkok : _bAsian Institute of Technology, _c1999
300			_a60 leaves
490	1		_aThesis ; _vno. AS-99-04
500			_aA thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Environment, Resources and Development
502			_aThesis (M.Sc.) - Asian Institute of Technology, 1999
520			_aAn 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.
650		0	_aShrimp culture
650		0	_aSoil salinization
650		0	_aCrop yields
700	1		_aLin, C. K., _eChairperson
700	1		_aHansen, G. K., _eExamination committee
700	0		_aPreeda Pakpian, _eExamination Committee
710	2		_aH.M. the King of Thailand Scholarship Program, _eScholarship donor
810	2		_aAsian Institute of Technology. _tThesis ; _vno. AS-99-04
856			_3Full-Text _uhttp://203.159.5.9/ait-thesis/detail.php?q=B12628
907			_a.b11789761 _bmnait _cu
902			_a240330
998			_b0 _c000529 _dm _ea _fu _g0
945			_lmnait
945			_lmnarc
942			_c22
942			_c40
909			_aBarcode : 30050120695233 _bCREATED : 2013-06-09 _cRECORD # : i12740433 _dLPATRON : 1025183 _eLCHKIN : 2014-08-23 _f# RENEWALS : 0 _g# OVERDUE : 0 _hIUSE3 : 1 _iTOT CHKOUT : 1 _jTOT RENEW : 0
909			_aBarcode : 30050120359632 _bCREATED : 2016-09-06 _cRECORD # : i13028418 _dLPATRON : 0 _eLCHKIN : - _f# RENEWALS : 0 _g# OVERDUE : 0 _hIUSE3 : 0 _iTOT CHKOUT : 0 _jTOT RENEW : 0
999			_c58066 _d58066