摘要
为研究酸雨对不同pH值水稻土中有机碳分解的影响,选择酸性(pH5.48)、碱性(pH8.18)和中性(pH6.70)水稻土(分别设置施用秸秆0、15g·kg-1土处理)在20℃条件下进行40d的培养试验,各土壤组分别用pH值为6.0、4.5、3.0的模拟雨水将土壤含水量调为400g·kg-1(以风干土计).结果表明:秸秆、酸雨和土壤共同对土壤系统CO2释放产生影响,秸秆的添加可显著提高土壤CO2释放速率.培养期间,酸雨未显著影响土壤有机碳分解,但对土壤中作物秸秆的分解影响显著.pH3.0酸雨处理下酸性和碱性土壤中秸秆40d总分解量比pH6.0处理高8%;酸雨抑制了中性水稻土中秸秆的分解,pH3.0酸雨处理下秸秆40d总分解量比pH6.0处理低15%.pH3.0酸雨处理下,酸性水稻土有机碳分解速率分别比中性和碱性水稻土高43%和50%(P<0.05),秸秆在中性水稻土中分解量分别比其在酸性和碱性水稻土中低17%和16%(P<0.05).
To evaluate the effects of acid rain on the organic carbon decomposition in different acidity soils, a 40-day incubation test was conducted with the paddy soils of pH 5.48, 6. 70 and 8.18. The soils were amended with 0 and 15 g · kg^-1 of rice straw, adjusted to the moisture content of 400 g · kg^-1 air-dried soil by using simulated rain of pH 6.0, 4.5, and 3.0, and incubated at 20 ℃. The results showed that straw, acid rain, and soil co-affected the CO2 emission from soil system. The amendment of straw increased the soil CO2 emission rate significantly. Acid rain had no significant effects on soil organic carbon decomposition, but significantly affected the straw decomposition in soil. When treated with pH 3.0 acid rain, the amount of decomposed straw over 40-day incubation in acid （pH 5.48） and alkaline （pH 8.18） soils was 8% higher, while that in neutral soil （pH 6. 70） was 15% lower, compared to the treatment of pH 6.0 rain. In the treatment of pH 3.0 acid rain, the decomposition rate of soil organic C in acid （pH 5.48） soil was 43% and 50% （P 〈0. 05） higher than that in neutral （pH 6.70） and alkaline （pH 8.18） soils, while the decomposition rate of straw in neutral soil was 17% and 16% （P 〈0. 05） lower than that in acid and alkaline soils, respectively.
出处
《应用生态学报》
CAS
CSCD
北大核心
2009年第2期480-484,共5页
Chinese Journal of Applied Ecology
基金
中国科学院知识创新工程重要方向资助项目(KZCX2-YW-305)
关键词
模拟酸雨
水稻土
秸秆
土壤有机碳
CO2排放
simulated acid rain
paddy soil
straw
soil organic carbon
CO2 emission
