Residual effects of biochar and application of biofilm biofertilizer on Alfisols physical properties and rice yield

Long-term and intensive use of chemical fertilizer reduce soil physical properties even plants yield. Especially on Alfisols with poor soil physical properties making it difficult for plant roots to penetrate and low water holding capacity. It is important to use biochar as environmentally-friendly soil conditioner and biofilm biofertilizer to reduce the use of chemical fertilizer and climate changes. This study examines the residual effect of coconut shell biochar in second season and the use of biofilm biofertilizer (BiO2) to increase soil physical properties and rice yield on Alfisol. This was pot experiment conducted at green house used a split-split plot design, with the main plot was biofilm biofertilizer (BiO2) concentration (0 and 100%), a sub-plot of biochar application method (mixed evenly with soil and spread on the soil surface), and a sub-sub-plot of biochar dosages (dose 0, 15 and 30 ton/ha). The results show that the K1C2D2 treatment combination (the residual effect of 30 ton/ha biochar applied by evenly mixed it with the soil a year before, combined with the used of BiO2) has the highest value in reducing soil bulk density (28%) and particle density (18.86%), and increasing soil porosity (36.78%), plant dry weight (261.51%) and rice yield (231.32%) than the control treatment.