The Effect of Microorganism Inoculants on the Color Changing of the Wheat Straws After Incorporated into Soil

Abstract. Straws color changing from lightness to darkness after incorporated into soil is one of the most important characters reflecting the degree of straws decomposition. To quickly and accurately identify the decomposition degree of wheat straws, a high-throughout quantitative image analysis method was developed based on the image grey values of the straws degraded in soil for different days. And the correlation between the values and the contents of the chemical components in the straws was investigated. The results indicated that the grey value representing the color of the straws had significant negative correlation with the content of residual ash in straws (r=0.834). The method was used to study on the microorganism inoculants functioning in straw decomposition. The results showed that there was significant difference between the straw with and without microorganism inoculants in grey value after 30 days. The final color of the straws with microorganism inoculants was much deeper than that of straws without inoculants. This means the microorganism inoculants could not only accelerate the decomposition speed of the wheat straws incorporated into the soil, but also affect their final mineralization degree.