Enhanced suppression of saprotrophs by ectomycorrhizal fungi under high level of nitrogen fertilization
Ectomycorrhizal fungi (EMF) are widespread in northern conifer forests. By competing with the free-living saprotrophic fungal and bacterial communities for limited soil nitrogen, EMF are expected to suppress litter decomposition and thus drive soil carbon accumulation. The EMF may also stimulate rhi...
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Frontiers Media S.A.
2022-08-01
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| Series: | Frontiers in Ecology and Evolution |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/fevo.2022.974449/full |
| _version_ | 1811340195676553216 |
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| author | Shuang Liang Wei Wang Xiaoyue Zeng Ran Wu Weile Chen |
| author_facet | Shuang Liang Wei Wang Xiaoyue Zeng Ran Wu Weile Chen |
| author_sort | Shuang Liang |
| collection | DOAJ |
| description | Ectomycorrhizal fungi (EMF) are widespread in northern conifer forests. By competing with the free-living saprotrophic fungal and bacterial communities for limited soil nitrogen, EMF are expected to suppress litter decomposition and thus drive soil carbon accumulation. The EMF may also stimulate rhizosphere microbial growth through inputs of labile plant carbon, and subsequently contribute to the soil carbon pool via microbial necromass. Here we examined the relative strength of these two potential EMF effects in a northern conifer plantation of the Saihanba Forest, the largest plantation in China. The soil fungal and bacterial biomass, as well as their respiration, were quantified within the two types of soil cores that either allow or exclude the ingrowth of EMF. We also set up a nitrogen fertilization gradient (0, 5, 10, 15 g N m–2 y–1) in this plantation to quantify the influence of external inorganic nitrogen on the EMF effects. We found evidence that EMF inhibit the overall fungal and bacteria biomass, confirming the suppression of saprotrophs by EMF. In addition, high levels of external nitrogen fertilization (15 g N m–2 y–1) might further enhance the suppression by EMF. In contrast, the presence of EMF consistently increased soil microbial respiration across all nitrogen fertilization levels, indicating that the carbon allocated to EMF could have been largely consumed by microbial respiration and contributed minimally to the accumulation of microbial biomass. Our results also indicated that the suppression of saprotrophs by EMF may play a critical role in driving continuous soil carbon accumulation in this northern pine plantation under atmospheric nitrogen deposition. |
| first_indexed | 2024-04-13T18:38:19Z |
| format | Article |
| id | doaj.art-cf4397bb52e540119efb2df32279da95 |
| institution | Directory Open Access Journal |
| issn | 2296-701X |
| language | English |
| last_indexed | 2024-04-13T18:38:19Z |
| publishDate | 2022-08-01 |
| publisher | Frontiers Media S.A. |
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| series | Frontiers in Ecology and Evolution |
| spelling | doaj.art-cf4397bb52e540119efb2df32279da952022-12-22T02:34:49ZengFrontiers Media S.A.Frontiers in Ecology and Evolution2296-701X2022-08-011010.3389/fevo.2022.974449974449Enhanced suppression of saprotrophs by ectomycorrhizal fungi under high level of nitrogen fertilizationShuang Liang0Wei Wang1Xiaoyue Zeng2Ran Wu3Weile Chen4College of Life Sciences, Zhejiang University, Hangzhou, ChinaDepartment of Ecology, College of Urban and Environmental Science and the Key Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, Beijing, ChinaCollege of Life Sciences, Zhejiang University, Hangzhou, ChinaCollege of Life Sciences, Zhejiang University, Hangzhou, ChinaCollege of Life Sciences, Zhejiang University, Hangzhou, ChinaEctomycorrhizal fungi (EMF) are widespread in northern conifer forests. By competing with the free-living saprotrophic fungal and bacterial communities for limited soil nitrogen, EMF are expected to suppress litter decomposition and thus drive soil carbon accumulation. The EMF may also stimulate rhizosphere microbial growth through inputs of labile plant carbon, and subsequently contribute to the soil carbon pool via microbial necromass. Here we examined the relative strength of these two potential EMF effects in a northern conifer plantation of the Saihanba Forest, the largest plantation in China. The soil fungal and bacterial biomass, as well as their respiration, were quantified within the two types of soil cores that either allow or exclude the ingrowth of EMF. We also set up a nitrogen fertilization gradient (0, 5, 10, 15 g N m–2 y–1) in this plantation to quantify the influence of external inorganic nitrogen on the EMF effects. We found evidence that EMF inhibit the overall fungal and bacteria biomass, confirming the suppression of saprotrophs by EMF. In addition, high levels of external nitrogen fertilization (15 g N m–2 y–1) might further enhance the suppression by EMF. In contrast, the presence of EMF consistently increased soil microbial respiration across all nitrogen fertilization levels, indicating that the carbon allocated to EMF could have been largely consumed by microbial respiration and contributed minimally to the accumulation of microbial biomass. Our results also indicated that the suppression of saprotrophs by EMF may play a critical role in driving continuous soil carbon accumulation in this northern pine plantation under atmospheric nitrogen deposition.https://www.frontiersin.org/articles/10.3389/fevo.2022.974449/fullGadgil effectmicrobial respirationnitrogen competitionnitrogen depositionphospholipid fatty acid analysisScots pine |
| spellingShingle | Shuang Liang Wei Wang Xiaoyue Zeng Ran Wu Weile Chen Enhanced suppression of saprotrophs by ectomycorrhizal fungi under high level of nitrogen fertilization Frontiers in Ecology and Evolution Gadgil effect microbial respiration nitrogen competition nitrogen deposition phospholipid fatty acid analysis Scots pine |
| title | Enhanced suppression of saprotrophs by ectomycorrhizal fungi under high level of nitrogen fertilization |
| title_full | Enhanced suppression of saprotrophs by ectomycorrhizal fungi under high level of nitrogen fertilization |
| title_fullStr | Enhanced suppression of saprotrophs by ectomycorrhizal fungi under high level of nitrogen fertilization |
| title_full_unstemmed | Enhanced suppression of saprotrophs by ectomycorrhizal fungi under high level of nitrogen fertilization |
| title_short | Enhanced suppression of saprotrophs by ectomycorrhizal fungi under high level of nitrogen fertilization |
| title_sort | enhanced suppression of saprotrophs by ectomycorrhizal fungi under high level of nitrogen fertilization |
| topic | Gadgil effect microbial respiration nitrogen competition nitrogen deposition phospholipid fatty acid analysis Scots pine |
| url | https://www.frontiersin.org/articles/10.3389/fevo.2022.974449/full |
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