How Do Microbial Communities Adapt to Soil Acidification?
Temperate grasslands in northern China have experienced extreme soil acidification in last 30 years due to increasing acid deposition and unsustainable management. Long-term soil acidification may lead to leaching of base cations, nutrient imbalances and metal stress for soil biomes.
How do microbial communities adapt to the threats of soil acidification?
Recently, a research team from the Institute of Applied Ecology of the Chinese Academy of Sciences addressed this issue by experimentally adding elemental S to simulate soil acidification in a meadow steppe of Inner Mongolia.
As expected, the researchers found that soil acidification strongly increased relative abundance of fungi community and subsequently led to a conversion from microbial N limitation to C limitation with decreasing soil pH. They also found the threshold pH between microbial N and C limitation in this semi-arid grassland is 6.6.
The researchers further examine the underlying mechanisms for the microbial responses to soil acidification. The results showed microbial community increased C acquisition and utilization efficiency to adapt to C limitation under low soil pH. Surprisingly, the results further indicated that the stoichiometric pathway counteracted the pathway of metal stress as widely accepted in soil acidification.
Overall, these results highlight the importance of stoichiometric controls in microbial adaption to soil acidification, which may help predict soil microbial responses to future climate change.
The study, entitled "Enhanced carbon acquisition and use efficiency alleviate microbial carbon relative to nitrogen limitation under soil acidification" has been published in Ecological Processes.
The study is financially supported by the National Natural Science Foundation of China, the Strategic Priority Research Program of CAS, and the Key State Research & Development Program of China.
Institute of Applied Ecology, Chinese Academy of Sciences