{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T13:00:29Z","timestamp":1785416429401,"version":"3.56.0"},"reference-count":51,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T00:00:00Z","timestamp":1781481600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["32271704"],"award-info":[{"award-number":["32271704"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["32271704"],"award-info":[{"award-number":["32271704"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100021171","name":"Basic and Applied Basic Research Foundation of Guangdong Province","doi-asserted-by":"crossref","award":["2022A1515010562"],"award-info":[{"award-number":["2022A1515010562"]}],"id":[{"id":"10.13039\/501100021171","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Shenzhen Science and Technology Project","award":["JCYJ20230808105410020"],"award-info":[{"award-number":["JCYJ20230808105410020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Plants"],"abstract":"<jats:p>The role of mangrove root exudates in mediating the nitrogen cycle, particularly under high dissolved inorganic nitrogen (DIN) input, in coastal ecosystems remains unclear. This research investigated variation in the root exudates, and nitrogen transformation and output, in constructed mangrove wetlands planted with Kandelia obovata under high, moderate, and low nitrogen-input levels (PCWs-H, PCWs-M, and PCWs-L, respectively). PCWs-H promoted increased root density and biomass accumulation, enhancing soil nitrogen sequestration, whereas PCWs-L induced greater specific root length, specific root surface area, and number of root tips. These changes directly influenced denitrification efficiency. Hydroxymethoxyphenylcarboxylic acid-O-sulfate and Arg-Ser released in root exudates under PCWs-H might act as potential denitrification inhibitors, thereby suppressing denitrifiers and impairing dissolved nitrogen purification. Elevated nitrogen loading predominantly limited denitrification, resulting in relative NO3\u2212-N removal rates of PCWs-H &lt; PCWs-M &lt; PCWs-L (p &lt; 0.05). Compared with PCWs-H and PCWs-L, the enhanced soil organic nitrogen storage under PCWs-M was associated with flavonoids in root exudates. Metagenomic analysis showed that denitrification was the dominant nitrogen removal pathway. Nitrogen loading influenced the effects of root exudates on the microbial community. Under PCWs-H, triterpenoids promoted norBC and nirK\/S abundance but depressed amoABC abundance. Sterols and flavonoids in exudates under PCWs-L depressed nosZ abundance, instead activating dissimilatory nitrate reduction to ammonium. Compared with PCWs-H and PCWs-L, N2O emissions were minimal under PCWs-M. This study revealed that mangrove root exudates mediate the nitrogen cycle in mangrove wetlands, providing a theoretical basis for local authorities to manage DIN inputs and mitigate N2O emissions.<\/jats:p>","DOI":"10.3390\/plants15121851","type":"journal-article","created":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T15:00:48Z","timestamp":1781535648000},"page":"1851","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Nitrogen Input Alters Root Exudation of Kandelia obovata and Nitrogen Cycling in Constructed Mangrove Wetlands"],"prefix":"10.3390","volume":"15","author":[{"given":"Peiyin","family":"Wang","sequence":"first","affiliation":[{"name":"Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5369-0357","authenticated-orcid":false,"given":"Dongpeng","family":"Yin","sequence":"additional","affiliation":[{"name":"Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-6216-9221","authenticated-orcid":false,"given":"Guiping","family":"Fu","sequence":"additional","affiliation":[{"name":"Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaohan","family":"Yi","sequence":"additional","affiliation":[{"name":"Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhipeng","family":"Guo","sequence":"additional","affiliation":[{"name":"Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"622","DOI":"10.1016\/j.soilbio.2006.09.013","article-title":"Spatial and temporal variation of nitrous oxide and methane flux between subtropical mangrove sediments and the atmosphere","volume":"39","author":"Allen","year":"2007","journal-title":"Soil Biol. Biochem."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"559","DOI":"10.1038\/nature15538","article-title":"The vulnerability of Indo-Pacific mangrove forests to sea-level rise","volume":"526","author":"Lovelock","year":"2015","journal-title":"Nature"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"742","DOI":"10.1016\/j.oneear.2021.04.007","article-title":"Increasing nutrient inputs risk a surge of nitrous oxide emissions from global mangrove ecosystems","volume":"4","author":"Mao","year":"2021","journal-title":"One Earth"},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Jia, D., Qi, F., Xu, X., Feng, J.J., Wu, H., Guo, J.M., Lu, W.Z., Peng, R.H., Zhu, X.S., and Luo, Y.Q. (2016). Co-Regulations of Spartina alterniflora Invasion and exogenous nitrogen loading on soil N2O efflux in subtropical mangrove mesocosms. PLoS ONE, 11.","DOI":"10.1371\/journal.pone.0146199"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1430","DOI":"10.1038\/s41467-022-29161-3","article-title":"Structure and function of the soil microbiome underlying N2O emissions from global wetlands","volume":"13","author":"Bahram","year":"2022","journal-title":"Nat. Commun."},{"key":"ref_6","unstructured":"Ministry of Ecology and Environment (MEE) of the People\u2019s Republic of China (2024). Bulletin of Marine Ecology and Environment Status of China in 2023, (In Chinese)."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"174","DOI":"10.1104\/pp.18.00597","article-title":"Leaf amino acid supply affects photosynthetic and plant nitrogen use efficiency under nitrogen stress","volume":"178","author":"Perchlik","year":"2018","journal-title":"Plant Physiol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"e2081419","DOI":"10.1080\/15592324.2022.2081419","article-title":"Nitrogen application alleviates salt stress by enhancing osmotic balance, ROS scavenging, and photosynthesis of rapeseed seedlings (Brassica napus)","volume":"17","author":"Tian","year":"2022","journal-title":"Plant Signal. Behav."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1016\/j.ecss.2019.03.011","article-title":"Hidden contribution of shrimp farming effluents to greenhouse gas emissions from mangrove soils","volume":"221","author":"Queiroz","year":"2019","journal-title":"Estuar. Coast. Shelf Sci."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"138157","DOI":"10.1016\/j.chemosphere.2023.138157","article-title":"A novel autotrophic denitrification and nitrification integrated constructed wetland process for marine aquaculture wastewater treatment","volume":"321","author":"Zhao","year":"2023","journal-title":"Chemosphere"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"109607","DOI":"10.1016\/j.soilbio.2024.109607","article-title":"The effects of climate warming and exogenous nitrogen input on soil N2O emissions from mangroves","volume":"199","author":"Song","year":"2024","journal-title":"Soil Biol. Biochem."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"661","DOI":"10.1016\/j.tplants.2017.05.004","article-title":"How plant root exudates shape the nitrogen cycle","volume":"22","author":"Coskun","year":"2017","journal-title":"Trends Plant Sci."},{"key":"ref_13","unstructured":"Horst, M. (1995). Mineral Nutrition of Higher Plants, Academic Press. [2nd ed.]."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Lin, Y., Mei, L., Wei, Q., Li, B., Zhang, P., Sun, S., and Cui, G. (2022). Leymus chinensis resists degraded soil stress by modulating root exudate components to attract beneficial microorganisms. Front. Microbiol., 13.","DOI":"10.3389\/fmicb.2022.951838"},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Wu, H.L., Wang, X.Z., and He, X.J. (2017). Effects of selected root exudate components on nitrogen removal and development of denitrifying bacteria in constructed wetlands. Water, 9.","DOI":"10.3390\/w9060430"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"80","DOI":"10.1016\/j.tplants.2021.08.003","article-title":"Root exudates impact plant performance under abiotic stress","volume":"27","author":"Chai","year":"2022","journal-title":"Trends Plant Sci."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"620","DOI":"10.1111\/nph.12944","article-title":"Evidence for biological denitrification inhibition (BDI) by plant secondary metabolites","volume":"204","author":"Bardon","year":"2014","journal-title":"New Phytol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1007\/s00299-019-02447-5","article-title":"Root exudates: From plant to rhizosphere and beyond","volume":"39","year":"2020","journal-title":"Plant Cell Rep."},{"key":"ref_19","unstructured":"Zhu, Q.Y., Jiang, N., Sun, W.J., Chen, L.C., Pan, X.F., and Xiong, X.Y. (2023). Coordinated monitoring of nitrogen and phosphorus pollution in Shenzhen river and Shenzhen bay based on UV\u2013visible absorption spectroscopy sensor. Ecol. Environ. Monit. Three Gorges, 244\u2013251."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"108391","DOI":"10.1016\/j.soilbio.2021.108391","article-title":"Comparing root exudate collection techniques: An improved hybrid method","volume":"161","author":"Williams","year":"2021","journal-title":"Soil Biol. Biochem."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"134095","DOI":"10.1016\/j.jclepro.2022.134095","article-title":"Root exudates release from Myriophyllum aquaticum and effects on nitrogen removal by constructed wetlands","volume":"375","author":"Xu","year":"2022","journal-title":"J. Clean. Prod."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"e14315","DOI":"10.1111\/ppl.14315","article-title":"Genetic control of root morphology in response to nitrogen across rapeseed diversity","volume":"176","author":"Haelterman","year":"2024","journal-title":"Physiol. Plant."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"209","DOI":"10.1007\/s11104-024-06793-6","article-title":"The impacts of different nitrogen supply on root traits, root exudates, and soil enzyme activities of exotic and native plant communities","volume":"508","author":"Li","year":"2024","journal-title":"Plant Soil"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"505","DOI":"10.1111\/nph.13363","article-title":"Redefining fine roots improves understanding of below-ground contributions to terrestrial biosphere processes","volume":"207","author":"McCormack","year":"2015","journal-title":"New Phytol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"415","DOI":"10.1007\/s11104-017-3555-8","article-title":"The relationship between root exudation properties and root morphological traits of cucumber grown under different nitrogen supplies and atmospheric CO2 concentrations","volume":"425","author":"Li","year":"2018","journal-title":"Plant Soil"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"101234","DOI":"10.1016\/j.xplc.2024.101234","article-title":"Phosphatidic acid signaling in modulating plant reproduction and architecture","volume":"6","author":"Yao","year":"2025","journal-title":"Plant Commun."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"177776","DOI":"10.1016\/j.scitotenv.2024.177776","article-title":"Metabolomic insights into rhizosphere soil carbon component variations of Phragmites communis in the exposure of propranolol","volume":"957","author":"Jin","year":"2024","journal-title":"Sci. Total Environ."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"155801","DOI":"10.1016\/j.scitotenv.2022.155801","article-title":"L-theanine exuded from Camellia sinensis roots regulates element cycling in soil by shaping the rhizosphere microbiome assembly","volume":"837","author":"Xie","year":"2022","journal-title":"Sci. Total Environ."},{"key":"ref_29","first-page":"1358","article-title":"Effect of phenolic acid Allelochemicals on nutrient supply capacity of rhizosphere soil","volume":"40","author":"Xu","year":"2024","journal-title":"J. Ecol. Rural Environ."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"366","DOI":"10.1016\/S1001-0742(10)60418-4","article-title":"Nitrification performance of nitrifying bacteria immobilized in waterborne Polyurethane at low ammonia nitrogen concentrations","volume":"23","author":"Dong","year":"2011","journal-title":"J. Environ. Sci."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"697","DOI":"10.1016\/j.scitotenv.2017.04.150","article-title":"Effects of root exudates on denitrifier gene abundance, community structure and activity in a micro-polluted constructed wetland","volume":"598","author":"Wu","year":"2017","journal-title":"Sci. Total Environ."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"108076","DOI":"10.1016\/j.soilbio.2020.108076","article-title":"Nitrogen addition alters composition, diversity, and functioning of microbial communities in mangrove soils: An incubation experiment","volume":"153","author":"Craig","year":"2021","journal-title":"Soil Biol. Biochem."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"5301","DOI":"10.5194\/essd-15-5301-2023","article-title":"Global carbon budget 2023","volume":"15","author":"Pierre","year":"2023","journal-title":"Earth Syst. Sci. Data"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1265","DOI":"10.1098\/rstb.2011.0317","article-title":"Nitrous oxide emissions from wastewater treatment processes","volume":"367","author":"Law","year":"2012","journal-title":"Philos. Trans. R. Soc. B Biol. Sci."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1258","DOI":"10.1021\/acs.est.8b04871","article-title":"Exploring utilization of recycled agricultural biomass in constructed wetlands: Characterization of the driving force for high-rate nitrogen removal","volume":"53","author":"Jia","year":"2019","journal-title":"Environ. Sci. Technol."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"159153","DOI":"10.1016\/j.scitotenv.2022.159153","article-title":"The long overlooked microalgal nitrous oxide emission: Characteristics, mechanisms, and influencing factors in microalgae-based wastewater treatment scenarios","volume":"856","author":"Zhang","year":"2023","journal-title":"Sci. Total Environ."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"45","DOI":"10.1007\/s10705-007-9094-6","article-title":"Soil aggregates control N cycling efficiency in long-term conventional and alternative cropping systems","volume":"79","author":"Kong","year":"2007","journal-title":"Nutr. Cycl. Agroecosystems"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"263","DOI":"10.1038\/nrmicro.2018.9","article-title":"The microbial nitrogen-cycling network","volume":"16","author":"Kuypers","year":"2018","journal-title":"Nat. Rev. Microbiol."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"171916","DOI":"10.1016\/j.scitotenv.2024.171916","article-title":"Dredging wastewater discharge from shrimp ponds affects mangrove soil physical-chemical properties and enzyme activities","volume":"926","author":"Chen","year":"2024","journal-title":"Sci. Total Environ."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"4818","DOI":"10.1038\/s41598-019-41146-9","article-title":"Interactive influences of intercropping by nitrogen on flavonoid exudation and nodulation in faba bean","volume":"9","author":"Liu","year":"2019","journal-title":"Sci. Rep."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"120277","DOI":"10.1016\/j.watres.2023.120277","article-title":"New insights into the effects of wetland plants on nitrogen removal pathways in constructed wetlands with low C\/N ratio wastewater: Contribution of partial denitrification-anammox","volume":"243","author":"Yao","year":"2023","journal-title":"Water Res."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"9320","DOI":"10.1021\/acs.est.8b02133","article-title":"T Plant-microbe interactions drive denitrification rates, dissolved nitrogen removal, and the abundance of denitrification genes in stormwater control measures","volume":"52","author":"Morse","year":"2018","journal-title":"Environ. Sci. Technol."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"320","DOI":"10.1126\/science.aap9516","article-title":"A global atlas of the dominant bacteria found in soil","volume":"359","author":"Oliverio","year":"2018","journal-title":"Science"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"373","DOI":"10.1016\/j.jes.2020.09.002","article-title":"Performance and microbial community analysis of bioaugmented activated sludge for nitrogen-containing organic pollutants removal","volume":"101","author":"Zhang","year":"2021","journal-title":"J. Environ. Sci."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"234","DOI":"10.1038\/s41564-018-0316-2","article-title":"Cyanate and urea are substrates for nitrification by Thaumarchaeota in the marine environment","volume":"4","author":"Kitzinger","year":"2019","journal-title":"Nat. Microbiol."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"2150","DOI":"10.1038\/s41396-019-0418-8","article-title":"Phylogenomics suggests oxygen availability as a driving force in Thaumarchaeota evolution","volume":"13","author":"Ren","year":"2019","journal-title":"ISME J."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"757","DOI":"10.1016\/j.cej.2017.08.011","article-title":"Assessment of phenol effect on microbial community structure and function in an anaerobic denitrifying process treating high concentration nitrate wastewater","volume":"330","author":"Miao","year":"2017","journal-title":"Chem. Eng. J."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"133495","DOI":"10.1016\/j.jclepro.2022.133495","article-title":"Incorporation of the sulfur cycle in sustainable nitrogen removal systems\u2014A review","volume":"372","author":"Grubba","year":"2022","journal-title":"J. Clean. Prod."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"165908","DOI":"10.1016\/j.scitotenv.2023.165908","article-title":"Nitrate removal in iron sulfide-driven autotrophic denitrification biofilter: Biochemical and chemical transformation pathways and its underlying microbial mechanism","volume":"901","author":"Yang","year":"2023","journal-title":"Sci. Total Environ."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"154320","DOI":"10.1016\/j.jplph.2024.154320","article-title":"Identification and analysis of flavonoid pathway genes in responsive to drought and salinity stress in Medicago truncatula","volume":"302","author":"He","year":"2024","journal-title":"J. Plant Physiol."},{"key":"ref_51","doi-asserted-by":"crossref","unstructured":"Zhang, Y., Wang, F., Wang, L., Zhang, L., Espley, R.V., Lin-Wang, K., and Cao, F. (2024). The response of growth and transcriptome profiles of tea grey blight disease pathogen pestalotiopsis theae to the variation of exogenous l-theanine. Int. J. Mol. Sci., 25.","DOI":"10.3390\/ijms25063493"}],"container-title":["Plants"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2223-7747\/15\/12\/1851\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T04:15:21Z","timestamp":1781842521000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2223-7747\/15\/12\/1851"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,15]]},"references-count":51,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2026,6]]}},"alternative-id":["plants15121851"],"URL":"https:\/\/doi.org\/10.3390\/plants15121851","relation":{},"ISSN":["2223-7747"],"issn-type":[{"value":"2223-7747","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,15]]}}}