Eriksen Jørgen, Sørensen Peter, Elsgaard Lars
Dep. of Agroecology and Environment, Faculty of Agricultural Sciences, University of Aarhus, PO Box 50, 8830 Tjele, Denmark.
J Environ Qual. 2008 Jan 4;37(1):280-6. doi: 10.2134/jeq2007.0317. Print 2008 Jan-Feb.
Acidification of slurry with sulfuric acid is a recent agricultural practice that may serve a double purpose: reducing ammonia emission and ensuring crop sulfur sufficiency. We investigated S transformations in untreated and acidified pig slurry stored for up to 11 mo at 2, 10, or 20 degrees C. Furthermore, the fertilizer efficiency of sulfuric acid in acidified slurry was investigated in a pot experiment with spring barley. The sulfate content from acidification with sulfuric acid was relatively stable and even after 11 mo of storage the majority was in the plant-available sulfate form. Microbial sulfate reduction during storage of acidified pig slurry was limited, presumably due to initial pH effects and a limitation in the availability of easily degradable organic matter. Sulfide accumulation was observed during storage but the sulfide levels in acidified slurry did not exceed those of the untreated slurry for several months after addition. The S fertilizer value of the acidified slurry was considerable as a result of the stable sulfate pool during storage. The high content of inorganic S in the acidified slurry may potentially lead to development of odorous volatile sulfur-containing compounds and investigations are needed into the relationship between odor development and the C and S composition of the slurry.
用硫酸酸化猪粪是一种近期的农业实践，可能有双重目的：减少氨排放并确保作物硫充足。我们研究了在2、10或20摄氏度下储存长达11个月的未处理和酸化猪粪中的硫转化。此外，在春大麦盆栽试验中研究了硫酸在酸化猪粪中的肥料效率。硫酸酸化产生的硫酸盐含量相对稳定，即使储存11个月后，大部分仍以植物可利用的硫酸盐形式存在。酸化猪粪储存期间微生物硫酸盐还原作用有限，可能是由于初始pH值的影响以及易降解有机物可用性的限制。储存期间观察到硫化物积累，但添加后几个月内，酸化猪粪中的硫化物水平并未超过未处理猪粪中的水平。由于储存期间硫酸盐池稳定，酸化猪粪的硫肥价值可观。酸化猪粪中无机硫含量高可能会导致产生有气味的挥发性含硫化合物，需要对气味产生与猪粪碳和硫组成之间的关系进行研究。
