Improving soil silicon and selected fertility status for rice production through rice-mill waste application in lowland sawah rice field of southeastern Nigeria

Abstract

Purpose Rice-mill wastes are generated in large amounts in Ishiagu, Ebonyi State, Nigeria. These wastes can potentially be utilized for rice production and in improving soil attributes. This study evaluated the effects of rice-mill wastes on soil chemical properties and rice yield in sawah rice management. Methods A sawah rice field in an inland valley of southeastern Nigeria was used in 2014 and 2015 cropping seasons for the study. Sawah refers to an Indo-Malaysian term for rice paddy. It involves the manipulation of some soil physical properties in form of ecological engineering works, by bunding, puddling and leveling of lowland rice field for water control and management. Two rice-mill wastes [rice husk ash (RHA) and rice husk dust (RHD) applied at 0, 2.5, 5, 7.5, 10 and 12.5 t ha −1 ] and the control were built into a split-plot in a randomized complete block design with three replications. Results Bio-waste application had significant (p < 0.05) improved effects on the soil organic carbon, available P, soil available Si and total N compared with the unamended (control) treatment. There was significant (p < 0.05) increase in rice grain yield from 5.05 to 5.80 t ha −1 (for RHA) and 6.17-6.96 t/ha (for RHD) compared with 2.35-2.8 t ha −1 (control treatment) in both cropping seasons. Conclusion RHD and RHA treatments had significantly higher rice grain yield compared with the control treatment. Overall, rice grain yield was higher under RHD treatment compared with RHA treatment. This result demonstrated that RHA and RHD are potential agricultural resource for rice production in the study area.

Rice Husk Dust and NPK Improve Soil Chemical Properties and Growth Response of Jatropha

“…The highest amount of organic carbon and organic matter (2.00% and 3.46% respectively) were recorded in plot that had 5tonha -1 RHD and 3tonha -1 NPK, while their least values were obtained in plot that had only 5tonha -1 NPK. The observed rate of enhancement in soil organic carbon and organic matter could be attributed to the high content of organic carbon in the RHD as also observed by Nwaite et al [7]. This findings can be justified on the bases that while organic manures improve soil biology and organics at sustainable levels [29], mineral fertilizers use at consistent manner are known to destroy soil health especially soil organic matter [29].…”

“…During rice refining processes, the husks are removed from grains. It is of little commercial value and because of its high silicon dioxide content; it is not useful to feed either human or cattle [7], but can be incorporated into the soil to enhance soil fertility and crop productivity. For example, organic modification of soil with rice husk was found effective in improving the nutrient status and thus increased the yield of many crops like cowpea and rice [6].…”

Influence of Silicon Fertilization on Nitrogen Fractions and Nutrient Status of Rice Grown Soils in Telangana State

“…There was a built-up to an extent of 0.68 percent in available Si content of the soil when compared to the initial status even without its fertilization. This could be due to the reason that Si fertilizers increased the content of plantavailable Si compounds [24] in the soil. This was attributed to the possibility of sorption and desorption of silicate fertilizer under the wetland rice ecosystem of the present study.…”

Bio-fuel Production Potentials of Jatropha, Produced by Combined Application of Rice Husk Dust and NPK in Southeastern Nigeria

“…What was still unclear on the general phenomenon of low Jatropha yield at younger ages has been made clearer through the improvement on soil fertility properties by the addition of RHD and NPK. The soil fertility enhancement potentials of rice husk dust in highly weathered acidity tropical soils have been reported by several authors [30] Azu et al [9] Nwaite, et al [31]. Jatropha cultivation traditionally receives minimal care in terms of soil fertility maintenance.…”

“…Thus, Omar et al [34] discovered significant increased in seed and oil quantity of Jatropha produced in soils treated with different rates of nitrogen and potassium fertilizers. Njoku et al [8] and Nwaite et al [31], in their separate studies observed improved soil fertility and corresponding plant response when rice husk dust was used as manure in ultisols of southeastern Nigeria.…”