Lignin Loading Effect on Biodegradability and Nitrogen Release Properties of Urea Modified Tapioca Starch in Wet Soil

Plant based biopolymers are abundantly and easily available naturally biodegradable raw materials to prepare slow release nitrogen technologies. To test the lignin loading effect on biodegradability of the slow release fertilizer (SRF) and nitrogen release applications, a pot experiment under real soil conditions was conducted. Lignin at different loading percentages 5%, 10%, 15% and 20% were mixed with urea-modified tapioca starch acting as slow release fertilizer (SRF). Increasing the percentage of lignin to starch reduced the weight loss with improved nitrogen slow release properties in wet soil. Soil microbial biomass was negatively correlated with increase of lignin percentages. Lignin is a low cost biopolymer and can be used to improve starch biodegradation and its slow release nitrogen properties.