Abstract
The effect of different rice plantation periods on the properties of selected soils on an alluvial plain was studied. Soils were sampled in fields cultivated for 6, 16, 26, and over forty years. In each rice cultivated and nonrice cultivated field, three soil profiles and six nearby auger holes were studied. This study indicated that continuous rice cultivation changed the soil moisture regime from xeric to aquic, the soil color from brown to grayish, and the surface horizons from mollic to ochric epipedon. With increasing duration of cultivation, the abundance of redoximorphic features increased and the soil structure changed from granular or blocky to massive. Therefore, the soil order changed from Mollisols to Inceptisols. No illuviation and eluviation of clay minerals occurred as a consequence of the rice cultivation. X-ray diffraction analysis showed that the clay minerals in the nonrice cultivated field were illite, vermiculite, montmorillonite, kaolinite, and chlorite, and, in the rice field, they were illite, montmorillonite, kaolinite, and chlorite, respectively. However, with increasing the period of cultivation, the amount of illite and vermiculite decreased while the amount of montmorillonite increased. The pH values of the saturated soil surface during the middle stage of rice growth shifted toward neutrality. The Eh of the surface horizons of the paddy soils under the field conditions were +40, −12, −84, and −122 mV, respectively, while the Eh in the nonpaddy soils were close to +90 mV. The amounts of organic matter and available Fe, Mn, Zn, and Cu increased, while the available K decreased in the paddy soils.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.