INFLUENCE OF COAL FLY ASH PELLET AGGREGATES ON THE GROWTH AND NUTRIENT COMPOSITION OF BRASSICA CAMPESTRIS AND PHYSICOCHEMICAL PROPERTIES OF GREY SOILS IN OKINAWA, JAPAN

Abstract

Two different types of coal fly ash-based pellet aggregates (PA) with 5 mm [small PA (SPA)] and 10 mm [large PA (LPA)] diameters were produced from coal fly ash (CFA) and paper waste (PW). Both types of PA were utilized as soil amendments to enhance poor physicochemical properties of problematic grey soil in Okinawa, Japan for the cultivation of Brassica campestris. Grey soil was amended with SPA alone, LPA alone and both SPA and LPA. The growth and yield parameters of Brassica campestris were determined. PA addition as a soil amendment improved the physicochemical properties of the amendment mixtures compared to grey soil without any amendments. Moreover, PA addition increased the growth and yield parameters of Brassica campestris compared to grey soil control. It can be concluded that PA can be utilized as a soil amendment to improve the crop production in problematic grey soil in Okinawa, Japan.

Keywords:

• coal fly ash
• fertilizer
• grey soils
• synthetic aggregates
• soil amendment

ACKNOWLEDGMENTS

Most sincere thanks and appreciation are extended to the higher education ministry of Japan (Monbukagakusho) and Okinawa Electric Company in Okinawa, Japan for providing financial support to conduct this study. Special thanks are extended to H. Susuki for his excellent assistance throughout the research period.