Organic fertilizer helps increase rice and wheat yields by 3%, similar to chemical fertilizer. It also improves soil quality by reducing bulk density and increasing nutrients like organic matter and nitrogen. Biochar and ordinary organic fertilizer work better than straw for soil improvement. Combining organic fertilizer with chemical fertilizer boosts crop yield but doesn't enhance soil quality as much. Over time, organic fertilizer boosts crop yield and soil fertility. Acidic soil benefits the most from organic fertilizer. Soil density affects crop yield negatively, while nitrogen and phosphorus levels boost it.