TY - JOUR
T1 - Increased productivity of rainfed lowland rice by incorporation of pond sediments in Northeast Thailand
AU - Mochizuki, Atsushi
AU - Homma, Koki
AU - Horie, Takeshi
AU - Shiraiwa, Tatsuhiko
AU - Watatsu, Eiko
AU - Supapoj, Nopporn
AU - Thongthai, Chamnean
PY - 2006/4/30
Y1 - 2006/4/30
N2 - Northeast Thailand is one of the representative rainfed rice culture areas in Asia, where rice productivity is limited not only by unstable rainfall but also by poor soil. The objective of this study was to improve rainfed rice yield at degraded fields in upper toposequence by incorporation of sediment soil accumulated at the lowest toposequence in mini-watersheds. We collected sediment soil from the pond when it was dry in the dry season in 2001 and placed it uniformly on the experimental field at a thickness of 5 cm, and incorporated it into the plow layer by double plowings and puddling. The clay content, soil organic carbon (SOC) content and cation exchange capacity (CEC) of the pond sediment soil were 0.42 kg kg-1, 12.9 g kg-1 and 13.8 cmol kg-1, respectively, those of the field soil before the incorporation were 0.08, 4.6 and 5.0, respectively, and those after the incorporation were 0.19, 5.7 and 7.1, respectively. Rice cultivar KDML105 was grown under rainfed condition, incorporated with and without the pond sediment soil, each with and without fertilization (four treatments in total) for the seasons from 2001 to 2003. Incorporation of the pond sediments increased rice yield in the fertilized plot by 28% on the average over three seasons, but not in the unfertilized plots. The yield increase in the fertilized plot was associated with increased fertilizer-N recovery efficiency. Since incorporation of the pond sediment did not significantly improve field water holding capacity and mineralizable N in soil, its effect on the fertilizer-N recovery efficiency and rice yield could be ascribed to the increased CEC. As much clay sediments rich in SOC and clay are accumulated in the lower toposequence such as the bottom of ponds, the present study suggests that incorporation of pond sediment soil into fields is an effective technology to improve rainfed rice yield at upper toposequence in mini-watersheds in Northeast Thailand.
AB - Northeast Thailand is one of the representative rainfed rice culture areas in Asia, where rice productivity is limited not only by unstable rainfall but also by poor soil. The objective of this study was to improve rainfed rice yield at degraded fields in upper toposequence by incorporation of sediment soil accumulated at the lowest toposequence in mini-watersheds. We collected sediment soil from the pond when it was dry in the dry season in 2001 and placed it uniformly on the experimental field at a thickness of 5 cm, and incorporated it into the plow layer by double plowings and puddling. The clay content, soil organic carbon (SOC) content and cation exchange capacity (CEC) of the pond sediment soil were 0.42 kg kg-1, 12.9 g kg-1 and 13.8 cmol kg-1, respectively, those of the field soil before the incorporation were 0.08, 4.6 and 5.0, respectively, and those after the incorporation were 0.19, 5.7 and 7.1, respectively. Rice cultivar KDML105 was grown under rainfed condition, incorporated with and without the pond sediment soil, each with and without fertilization (four treatments in total) for the seasons from 2001 to 2003. Incorporation of the pond sediments increased rice yield in the fertilized plot by 28% on the average over three seasons, but not in the unfertilized plots. The yield increase in the fertilized plot was associated with increased fertilizer-N recovery efficiency. Since incorporation of the pond sediment did not significantly improve field water holding capacity and mineralizable N in soil, its effect on the fertilizer-N recovery efficiency and rice yield could be ascribed to the increased CEC. As much clay sediments rich in SOC and clay are accumulated in the lower toposequence such as the bottom of ponds, the present study suggests that incorporation of pond sediment soil into fields is an effective technology to improve rainfed rice yield at upper toposequence in mini-watersheds in Northeast Thailand.
KW - Clay
KW - Degraded soil
KW - Nitrogen recovery efficiency
KW - Rainfed rice
KW - Soil amelioration
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U2 - 10.1016/j.fcr.2005.08.007
DO - 10.1016/j.fcr.2005.08.007
M3 - Article
AN - SCOPUS:32644489280
SN - 0378-4290
VL - 96
SP - 422
EP - 427
JO - Field Crops Research
JF - Field Crops Research
IS - 2-3
ER -
