Zhu Xue-Zhu, Huang Yao, Yang Xin-Zhong
College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China.
Ying Yong Sheng Tai Xue Bao. 2009 Feb;20(2):480-4.
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 x kg(-1) of rice straw, adjusted to the moisture content of 400 g x kg(-1) air-dried soil by using simulated rain of pH 6.0, 4.5, and 3.0, and incubated at 20 degrees C. 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.
为评估酸雨对不同酸度土壤中有机碳分解的影响，利用pH值分别为5.48、6.70和8.18的水稻土进行了为期40天的培养试验。向土壤中添加0和15 g·kg⁻¹的稻草，用pH值为6.0、4.5和3.0的模拟降雨将土壤水分含量调节至400 g·kg⁻¹风干土，然后在20℃下培养。结果表明，稻草、酸雨和土壤共同影响土壤系统的二氧化碳排放。添加稻草显著提高了土壤二氧化碳排放速率。酸雨对土壤有机碳分解没有显著影响，但对土壤中稻草的分解有显著影响。与pH值为6.0的降雨处理相比，用pH值为3.0的酸雨处理时，酸性（pH 5.48）和碱性（pH 8.18）土壤中40天培养期内稻草的分解量高出8%，而中性土壤（pH 6.70）中则低15%。在pH值为3.0的酸雨处理中，酸性（pH 5.48）土壤中土壤有机碳的分解速率分别比中性（pH 6.70）和碱性（pH 8.18）土壤高43%和50%（P<0.05），而中性土壤中稻草分解速率分别比酸性和碱性土壤低17%和16%（P<0.05）。
