Chin J Plant Ecol ›› 2022, Vol. 46 ›› Issue (1): 1-17.DOI: 10.17521/cjpe.2021.0283

• Research Articles •     Next Articles

Soil pH modulates nitrogen transfer from nitrogen-fixing plants to non-nitrogen-fixing plants

Li-Na WANG1, Yong-Qiang YU1, Dong-Xu LU2, Ya-Kun TANG1,2,*()   

  1. 1College of Forestry, Northwest A&F University, Yangling, Shaanxi 712100, China
    2Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, Shaanxi 712100, China
  • Received:2021-08-04 Accepted:2021-10-22 Online:2022-01-20 Published:2022-04-13
  • Contact: Ya-Kun TANG
  • Supported by:
    the National Natural Science Foundation of China(41977425);the National Key R&D Program of China(2017YFA0604801)


Aims Nitrogen is the main component of protein and the essential nutrient for plant growth. Soil nitrogen deficiency is a common phenomenon in terrestrial ecosystems. Nitrogen-fixing plants can transfer biologically fixed nitrogen to non-nitrogen-fixing plants in mixed plantation community, which is one of the essential ways for non-nitrogen-fixing plants to obtain nitrogen. This nitrogen transfer is helpful to the restoration of degraded ecosystems, the construction of a stable community and the enhancement of ecosystem productivity. It is essential to identify the effects of environmental and biological factors on nitrogen transfer between nitrogen-fixing and non-nitrogen-fixing plants. Methods To realize this aim, we analyzed 118 pairs of data about nitrogen transfer proportion (ratio of nitrogen transfer to nitrogen content of non nitrogen-fixing plants, Ptransfer) using linear mixed model. These data were from experiments on 21 nitrogen-fixing plants and 23 non-nitrogen-fixing plants. Important findings The result showed that soil pH dominated the variation of Ptransfer (accounting for 44.04%), followed by mean annual temperature (accounting for 9.14%) and biomass ratio of nitrogen-fixing to non-nitrogen-fixing plants (accounting for 2.95%). As a random factor, the plant species difference accounted for 16.52% variation of Ptransfer. In addition, Ptransfer in alkaline soil was significantly higher than that in acidic soil. In acidic soil, the mean annual temperature (accounting for 12.49%) and soil total nitrogen content (accounting for 11.72%) were the main factors affecting Ptransfer. Ptransfer also increased significantly with the increase of mean annual temperature and soil total nitrogen content. In alkaline soil, the variation of Ptransfer was mainly influenced by the biomass ratio of nitrogen-fixing to non-nitrogen-fixing plants (accounting for 13.29%), mean annual precipitation (accounting for 10.73%) and soil total nitrogen content (accounting for 9.33%). The biomass ratio of nitrogen- fixing to non-nitrogen-fixing plants and Ptransfer were significantly higher in alkaline soil than in acidic soil. Meanwhile, significantly positive correlation was observed between Ptransfer in alkaline soil and mean annual precipitation and soil total nitrogen content. These results are meaningful to improve nitrogen transfer between nitrogen- fixing and non-nitrogen-fixing plants, to effectively alleviate the limitation of soil nitrogen on the growth of non-nitrogen-fixing plants and to build a stable plant community.

Key words: nitrogen-fixing plants, nitrogen transfer, soil pH, linear mixed model