Abstract: Net bags which simulated straw returning to field were employed to determine characteristics of decomposing and nutrients releasing of carbon,nitrogen,phosphorus and potassium of sugarcane leaves under different ways returned to field.The results showed that sugarcane leaves had fast decomposing speed during 0 to 60 days under different ways returned to field.Under covered with soil,covered with soil and plastic film and covered with plastic film only,the accumulated decay rate was 95.1%,94.6% and 82.1% respectively at the 180th day,and was ranked as:covered with soil >covered with soil and plastic film >covered with plastic film only.Releasing speed of nutrients of sugarcane leaves ranked as:potassium>phosphorus>nitrogen≈carbon.The accumulated releasing rate of carbon,nitrogen,phosphorus and potassium was 83.0% -95.0%,82.0% -95.1%,73.5% -97.0%,98.4% -99.7% respectively.We could reduce the content of potassic fertilizer in base manure consideration of nutrients releasing.Releasing speed of nutrients of sugarcane leaves was grate when we covered with soil or soil and plastic film,and they did not have a significant difference.Covered with plastic film could keep soil moisture and reduce weed growth.So we suggested using the way of covered with soil and plastic film when we returned sugarcane leaves to field.

Key words: Sugarcane leaves, The way returned to field, Characteristics of decomposing, Characteristics of nutrients releasing

CLC Number: 

• S141