Journalartikel

Jahr der Veröffentlichung: 2022

Zeitschrift: Soil Biology and Biochemistry

Bandnummer: 174

ISSN: 0038-0717

eISSN: 1879-3428

DOI Link: https://doi.org/10.1016/j.soilbio.2022.108835

Verlag: Elsevier

Abstract: 
Saltmarsh plants are important components of estuarine and coastal wetlands because they regulate ecosystem nitrogen (N) dynamics. However, complex interactions between the N uptake of saltmarsh plants and soil N transformation remain unclear. Here, we conducted a series of N-15 tracing experiments with native Phragmites australis, invasive Spartina alterniflora, and bulk sediment without plants to explore the effect of plants on soil N cycling. The results showed that the NH4+ and NO3- uptake rates by the saltmarsh plants were 4.62-5.38 mg N kg(-1) d(-1) and 1.29-2.90 mg N kg(-1) d(-1), respectively, and the invasive S. alterniflora had a higher N uptake than the native P. australis. The presence of saltmarsh plants promoted N mineralization and dissimilatory NO3- reduction to NH4+, increasing the available NH4+ supply for the plants. Conversely, NH4+ immobilization and autotrophic nitrification rates were drastically reduced in the presence of the saltmarsh plants, indicating that the plants were able to outcompete soil microorganisms in NH4+ acquisition. Meanwhile, heterotrophic nitrification (organic N oxidation), which accounted for 66-82% of the total nitrification, was stimulated by the saltmarsh plants. Increased heterotrophic nitrification in the saltmarsh plants helped to provide NO3- substrates to meet the needs of the soil microorganisms and the plants. The regulatory effect of the invasive S. alterniflora on soil gross N transformation was more pronounced than that of the native P. australis due to the higher N requirements of the former. Microbial carbon sources and energy sources, relevant gene abundances and exoenzyme activities were the main factors by which the saltmarsh plants regulated gross N transformations. Overall, our results show that there are various interactions between soil microorganisms and saltmarsh plants and that S. alterniflora accelerates gross N transformations in the soil to meet its large demand for N. These findings provide valuable insights into the ecological management of invasive plants in estuarine and coastal ecosystems.

Harvard-Zitierstil: Chen, S., Gao, D., Zhang, J., Müller, C., Li, X., Zheng, Y., et al. (2022) Invasive Spartina alterniflora accelerates soil gross nitrogen transformations to optimize its nitrogen acquisition in an estuarine and coastal wetland of China, Soil Biology and Biochemistry, 174, Article 108835. https://doi.org/10.1016/j.soilbio.2022.108835

APA-Zitierstil: Chen, S., Gao, D., Zhang, J., Müller, C., Li, X., Zheng, Y., Dong, H., Yin, G., Han, P., Liang, X., Liu, M., & Hou, L. (2022). Invasive Spartina alterniflora accelerates soil gross nitrogen transformations to optimize its nitrogen acquisition in an estuarine and coastal wetland of China. Soil Biology and Biochemistry. 174, Article 108835. https://doi.org/10.1016/j.soilbio.2022.108835