稻田土壤理化特征与甲烷排放对铁炉渣施加响应

Influence of physical and chemical characteristics and methane emission on iron slag in paddy fields

采用静态箱-气相色谱法对CK、2Mg/hm2(Fe I)、4Mg/hm2(Fe II)和8Mg/hm2(Fe III)铁炉渣施加后稻田甲烷排放及其环境因子进行了测定与分析。研究结果表明:观测期内,CK、Fe I、Fe II和Fe III样地甲烷排放量平均值分别为4.19、3.28、2.50、2.08mg/(m2.h);CK、Fe I、Fe II和Fe III样地土壤三价铁含量平均值分别为4.21、5.55、8.93、9.88mg/g;盐度平均值分别为0.62、0.84、0.79、0.93mS/cm;pH平均值分别为6.75、6.94、7.05、7.17;温度平均值分别为23.76、23.82、23.92、24.03℃。铁炉渣的施加显著增加了稻田土壤三价铁含量、盐度和pH值,但对土壤温度的影响不显著。三价铁、盐度和pH的升高可能是铁炉渣降低稻田甲烷排放的主要原因。

In order to clarify the influence of methane emission on iron slag in paddy fields, the methane emission and the environmental factors of control （CK） and after 2 Mghm^-2 （Fe I）, 4 Mg hm^-2 （Fe II）, and 8 Mg hm^-2 （Fe III） iron slag application were determined by static chamber-gas chromatogram. The results show： that methane emission fluxes were 0. 04-7.99, 0.03-7.33, 0.06-6.30, 0.08-5.12 Mg/m^2·h, and average values were 4. 19, 3.28, 2. 50, 2.08 mg/m2· h, respectively. Ferric contents were 1.32-7. 85, 2. 66-9. 11, 5. 80-12.48 and 2. 99-15.48 mg/g, and average values were 4.21, 5.55, 8. 93, 9.88 mg/g. Salinity were 0. 46-0. 73, 0. 67-1.01, 0. 65-0. 92, 0. 62-1.23 mS/cm, and average values were 0. 62, 0.84, 0.79, 0. 93 mS/cm; pH values were 6. 32-6. 99, 6.40-7. 18, 6. 44- 7.49, 6. 54-7.57, and averaged values were 6.75, 6. 94, 7.05, 7. 17. Temperature values were 19. 53-27.43, 19.43 -27.40, 19.87-27. 43 and 20. 30-27.47 ℃, and average values were 23. 76, 23. 82, 23.92 and 24. 03 ℃. Iron slag adding significantly increased soil ferric , salinity and pH values, but the temperature values were not significantly changed. Ferric, salinity and pH values may be the key factors to mediate the iron slag to decrease methane emission in paddy fields.