This study examined soil characteristics and the growth response of Rice along different positions of a toposequence in Awka, Anambra State, Nigeria. The soils were delineated using the Geomorphon algorithm in the Geographic Resources Analysis Support System (GRASS) Geographic Information System (GIS) environments. This was then readapted to reflect the Uplands, midslopes, and Lowlands. The results show that in the uplands, bulk density increased down the profile, silt decreased down the profile, and clay fluctuated with increasing soil depth. In the lowlands, sand and silt content decreased down the profile, while clay content increased down the profile. The clay content had an inverse relationship with saturated hydraulic conductivity, decreasing the profile. In the midslope, sand content increased, and silt content decreased, while clay content was high in the topsoil, fluctuating with increasing depth. This result shows that physiographic positions critically influence the nature, properties, and variation of soils across the landscape. The soil properties, in turn, influenced the growth response of the rice plants, with particular reference to varietal variations (FARO 44, 52, 58, 59). Due to its high sand content, high runoff rate, and saturated hydraulic conductivity, the upland yielded rice plants with a lower number of tillers and height, while the reverse was the case in the lowlands. This may be attributed to Rice thriving best under swampy conditions, which are prevalent in lowland areas. The relatively low hydraulic conductivity, and higher organic matter, clay content, and water accumulation in the lowlands consequently ensure a higher yield. Generally, the swamp rice varieties (FARO 44 and 52) performed best in the lowlands, while the upland varieties (FARO 58 and 59) performed best in the midslopes.
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