{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,27]],"date-time":"2026-04-27T10:48:52Z","timestamp":1777286932379,"version":"3.51.4"},"reference-count":29,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2015,7,27]],"date-time":"2015-07-27T00:00:00Z","timestamp":1437955200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2015,7,27]],"date-time":"2015-07-27T00:00:00Z","timestamp":1437955200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Sci Rep"],"abstract":"<jats:title>Abstract<\/jats:title><jats:p>Elevated emissions of sulfur dioxide, nitrogen oxides and ammonia in China have resulted in high levels of sulfur and nitrogen deposition, being contributors to soil acidification, especially in and near large cities. However, knowledge gaps still exist in the way that large cities shape spatial patterns of acid deposition. Here, we assessed the patterns of pH, sulfate, nitrate and ammonium in bulk precipitation and throughfall in southern China\u2019s forests by synthesizing data from published literature. Concentrations and fluxes of sulfate, nitrate and ammonium in bulk precipitation and throughfall exhibited a power-law increase with a closer distance to the nearest large cities and accordingly pH showed a logarithmic decline. Our findings indicate the occurrence of urban \u2018acid islands\u2019 with a critical radius of approximately 70\u2009km in southern China, receiving potential acid loads of more than 2 keq ha<jats:sup>\u22121<\/jats:sup> yr<jats:sup>\u22121<\/jats:sup>. These urban acid islands covered an area of 0.70\u2009million km<jats:sup>2<\/jats:sup>, accounting for nearly 30% of the land area in southern China. Despite a significant capacity to neutralize acids in precipitation, our analysis highlights a substantial contribution of ammonium to potential acid load. Our results suggest a joint control on emissions of multiple acid precursors from urban areas in southern China.<\/jats:p>","DOI":"10.1038\/srep12625","type":"journal-article","created":{"date-parts":[[2015,7,27]],"date-time":"2015-07-27T11:11:01Z","timestamp":1437995461000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":57,"title":["Spatial boundary of urban \u2018acid islands\u2019 in southern China"],"prefix":"10.1038","volume":"5","author":[{"given":"E.","family":"Du","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"W.","family":"de Vries","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"X.","family":"Liu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J.","family":"Fang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J. N.","family":"Galloway","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Y.","family":"Jiang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2015,7,27]]},"reference":[{"key":"BFsrep12625_CR1","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1016\/j.atmosenv.2007.09.003","volume":"42","author":"CK Chan","year":"2008","unstructured":"Chan, C. K. & Yao, X. Air pollution in mega cities in China. Atmos. Environ. 42, 1\u201342 (2008).","journal-title":"Atmos. Environ."},{"key":"BFsrep12625_CR2","doi-asserted-by":"publisher","first-page":"9839","DOI":"10.5194\/acp-11-9839-2011","volume":"11","author":"ZF Lu","year":"2011","unstructured":"Lu, Z. F., Zhang, Q. & Streets, D. G. Sulfur dioxide and primary carbonaceous aerosol emissions in China and India, 1996\u20132010. Atmos. Chem. Phys. 11, 9839\u20139864 (2011).","journal-title":"Atmos. Chem. Phys."},{"key":"BFsrep12625_CR3","doi-asserted-by":"publisher","first-page":"459","DOI":"10.1038\/nature11917","volume":"494","author":"XJ Liu","year":"2013","unstructured":"Liu, X. J. et al. Enhanced nitrogen deposition over China. Nature 494, 459\u2013462 (2013).","journal-title":"Nature"},{"key":"BFsrep12625_CR4","doi-asserted-by":"publisher","first-page":"418","DOI":"10.1021\/es0626133","volume":"40","author":"T Larssen","year":"2006","unstructured":"Larssen, T. et al. Acid rain in China. Environ. Sci. Technol. 40, 418\u2013425 (2006).","journal-title":"Environ. Sci. Technol."},{"key":"BFsrep12625_CR5","doi-asserted-by":"publisher","first-page":"8021","DOI":"10.1021\/es901430n","volume":"43","author":"Y Zhao","year":"2009","unstructured":"Zhao, Y. et al. Soil acidification in China: Is controlling SO2 emissions enough? Environ. Sci. Technol. 43, 8021\u20138026 (2009).","journal-title":"Environ. Sci. Technol."},{"key":"BFsrep12625_CR6","doi-asserted-by":"publisher","first-page":"2251","DOI":"10.1016\/j.envpol.2010.08.002","volume":"159","author":"XJ Liu","year":"2011","unstructured":"Liu, X. J. et al. Nitrogen deposition and its ecological impact in China: An overview. Environ. Pollut. 159, 2251\u20132264 (2011).","journal-title":"Environ. Pollut."},{"key":"BFsrep12625_CR7","doi-asserted-by":"publisher","first-page":"141","DOI":"10.1023\/A:1012263822014","volume":"130","author":"Y Maeda","year":"2001","unstructured":"Maeda, Y. et al. Material damage caused by acidic air pollution in East Asia. Water Air Soil Poll. 130, 141\u2013150 (2001).","journal-title":"Water Air Soil Poll."},{"key":"BFsrep12625_CR8","doi-asserted-by":"publisher","first-page":"1737","DOI":"10.1126\/science.1207824","volume":"333","author":"S Beirle","year":"2011","unstructured":"Beirle, S., Boersma, K. F., Platt, U., Lawrence, M. G. & Wagner, T. Megacity emissions and lifetimes of nitrogen oxides probed from space. Science 333, 1737\u20131739 (2011).","journal-title":"Science"},{"key":"BFsrep12625_CR9","doi-asserted-by":"publisher","first-page":"769","DOI":"10.1016\/j.chemosphere.2014.07.097","volume":"119","author":"C Reche","year":"2015","unstructured":"Reche, C. et al. Urban NH3 levels and sources in six major Spanish cities. Chemosphere 119, 769\u2013777 (2015).","journal-title":"Chemosphere"},{"key":"BFsrep12625_CR10","doi-asserted-by":"publisher","first-page":"474","DOI":"10.1016\/j.atmosenv.2014.09.005","volume":"98","author":"EZ Du","year":"2014","unstructured":"Du, E. Z., Jiang, Y., Fang, J. Y. & De Vries, W. Inorganic nitrogen deposition in China\u2019s forests: Status and characteristics. Atmos. Environ. 98, 474\u2013482 (2014).","journal-title":"Atmos. Environ."},{"key":"BFsrep12625_CR11","doi-asserted-by":"publisher","first-page":"15","DOI":"10.1007\/BF00483685","volume":"85","author":"JN Galloway","year":"1995","unstructured":"Galloway, J. N. Acid deposition: perspectives in time and space. Water Air Soil Poll. 85, 15\u201324 (1995).","journal-title":"Water Air Soil Poll."},{"key":"BFsrep12625_CR12","doi-asserted-by":"publisher","first-page":"143","DOI":"10.1007\/BF01257121","volume":"72","author":"H Sverdrup","year":"1994","unstructured":"Sverdrup, H. & De Vries, W. Calculating critical loads for acidity with the simple mass balance method. Water Air Soil Poll. 72, 143\u2013162 (1994).","journal-title":"Water Air Soil Poll."},{"key":"BFsrep12625_CR13","doi-asserted-by":"publisher","first-page":"89","DOI":"10.1016\/S0269-7491(99)00279-1","volume":"110","author":"T Larssen","year":"2000","unstructured":"Larssen, T. & Carmichael, G. R. Acid rain and acidification in China: the importance of base cation deposition. Environ. Pollut. 110, 89\u2013102 (2000).","journal-title":"Environ. Pollut."},{"key":"BFsrep12625_CR14","doi-asserted-by":"publisher","first-page":"3790","DOI":"10.1111\/gcb.12665","volume":"20","author":"XK Lu","year":"2014","unstructured":"Lu, X. K., Mao, Q. G., Gilliam, F. S., Luo, Y. Q. & Mo, J. M. Nitrogen deposition contributes to soil acidification in tropical ecosystems. Global Change Biol. 20, 3790\u20133801 (2014).","journal-title":"Global Change Biol."},{"key":"BFsrep12625_CR15","first-page":"385","volume":"12","author":"JM Hao","year":"2000","unstructured":"Hao, J. M., Wang, S. X., Liu, B. J. & He, K. B. Control strategy for sulfur dioxide and acid rain pollution in China. J. Environ. Sci-China 12, 385\u2013393 (2000).","journal-title":"J. Environ. Sci-China"},{"key":"BFsrep12625_CR16","doi-asserted-by":"publisher","first-page":"141","DOI":"10.1126\/science.231.4734.141","volume":"231","author":"SE Lindberg","year":"1986","unstructured":"Lindberg, S. E., Lovett, G. M., Richter, D. D. & Johnson, D. W. Atmospheric deposition and canopy interactions of major ions in a forest. Science 231, 141\u2013145(1986).","journal-title":"Science"},{"key":"BFsrep12625_CR17","doi-asserted-by":"publisher","first-page":"2134","DOI":"10.1139\/x26-242","volume":"26","author":"GM Lovett","year":"1996","unstructured":"Lovett, G. M., Nolan, S. S., Driscoll, C. T. & Fahey, T. J. Factors regulating throughfall flux in a New Hampshire forested landscape. Can. J. For. Res. 26, 2134\u20132144 (1996).","journal-title":"Can. J. For. Res."},{"key":"BFsrep12625_CR18","doi-asserted-by":"publisher","first-page":"3349","DOI":"10.1016\/1352-2310(96)00030-1","volume":"30","author":"GPJ Draaijers","year":"1996","unstructured":"Draaijers, G. P. J., Erisman, J. W., Sprangert, T. & Wyers, G. P. The application of throughfall measurements for atmospheric deposition monitoring. Atmos. Environ. 30, 3349\u20133361 (1996).","journal-title":"Atmos. Environ."},{"key":"BFsrep12625_CR19","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1007\/s00442-008-1188-6","volume":"159","author":"JP Sparks","year":"2009","unstructured":"Sparks, J. P. Ecological ramifications of the direct foliar uptake of nitrogen. Oecologia 159, 1\u201313 (2009).","journal-title":"Oecologia"},{"key":"BFsrep12625_CR20","doi-asserted-by":"publisher","first-page":"168","DOI":"10.1002\/jpln.200390024","volume":"166","author":"JJ Langusch","year":"2003","unstructured":"Langusch, J. J., Borken, W., Armbruster, M., Dise, N. B. & Matzner, E. Canopy leaching of cations in Central European forest ecosystems \u2013 a regional assessment. J. Plant Nutr. Soil Sci. 166, 168\u2013174 (2003).","journal-title":"J. Plant Nutr. Soil Sci."},{"key":"BFsrep12625_CR21","doi-asserted-by":"publisher","first-page":"97","DOI":"10.2307\/2260786","volume":"79","author":"CS Potter","year":"1991","unstructured":"Potter, C. S., Ragsdale, H. L. & Swank, W. T. Atmospheric deposition and foliar leaching in a regenerating southern Appalachian forest canopy. J. Ecol. 79, 97\u2013115 (1991).","journal-title":"J. Ecol."},{"key":"BFsrep12625_CR22","doi-asserted-by":"publisher","first-page":"839","DOI":"10.1007\/s10980-010-9461-6","volume":"25","author":"T Li","year":"2010","unstructured":"Li, T. et al. Fragmentation of China\u2019s landscape by roads and urban areas. Landscape Ecol. 25, 839\u2013853 (2010).","journal-title":"Landscape Ecol."},{"key":"BFsrep12625_CR23","doi-asserted-by":"publisher","first-page":"261","DOI":"10.1007\/s10533-013-9857-x","volume":"116","author":"K Redling","year":"2013","unstructured":"Redling, K., Elliott, E., Bain, D. & Sherwell, J. Highway contributions to reactive nitrogen deposition: Tracing the fate of vehicular NOx using stable isotopes and plant biomonitors. Biogeochemistry 116, 261\u2013274 (2013).","journal-title":"Biogeochemistry"},{"key":"BFsrep12625_CR24","doi-asserted-by":"publisher","first-page":"2","DOI":"10.1016\/S1001-0742(11)60724-9","volume":"24","author":"SX Wang","year":"2012","unstructured":"Wang, S. X. & Hao, J. M. Air quality management in China: Issues, challenges and options. J. Environ. Sci-China 24, 2\u201313 (2012).","journal-title":"J. Environ. Sci-China"},{"key":"BFsrep12625_CR25","doi-asserted-by":"publisher","first-page":"10036","DOI":"10.1021\/es501729d","volume":"48","author":"XQ Mao","year":"2014","unstructured":"Mao, X. Q., Zhou, J. & Corsetti, G. How well have China\u2019s Recent Five-Year Plans been implemented for energy conservation and air pollution control? Environ. Sci. Technol. 48, 10036\u201310044 (2014).","journal-title":"Environ. Sci. Technol."},{"key":"BFsrep12625_CR26","doi-asserted-by":"publisher","first-page":"473","DOI":"10.1038\/515473a","volume":"515","author":"J Tollefson","year":"2014","unstructured":"Tollefson, J. US\u2013China climate deal raises hopes for Lima talks. Nature 515, 473\u2013474 (2014).","journal-title":"Nature"},{"key":"BFsrep12625_CR27","first-page":"15","volume":"29","author":"A Singh","year":"2008","unstructured":"Singh, A. & Agrawal, M. Acid rain and its ecological consequences. J. Environ. Biol. 29, 15\u201324 (2008).","journal-title":"J. Environ. Biol."},{"key":"BFsrep12625_CR28","doi-asserted-by":"publisher","first-page":"1008","DOI":"10.1126\/science.1182570","volume":"327","author":"JH Guo","year":"2010","unstructured":"Guo, J. H. et al. Significant soil acidification in major Chinese croplands. Science 327, 1008\u20131010 (2010).","journal-title":"Science"},{"key":"BFsrep12625_CR29","doi-asserted-by":"publisher","first-page":"419","DOI":"10.1007\/978-94-017-9508-1_16","volume-title":"Critical Loads and Dynamic Risk Assessments: Nitrogen, Acidity and Metals in Terrestrial and Aquatic Ecosystems","author":"L Duan","year":"2015","unstructured":"Duan, L., Zhao, Y. & Hao, J. M. in Critical Loads and Dynamic Risk Assessments: Nitrogen, Acidity and Metals in Terrestrial and Aquatic Ecosystems (eds De Vries, W. et al.) Ch. 16, 419\u2013438 (Springer, 2015)."}],"container-title":["Scientific Reports"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.nature.com\/articles\/srep12625.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.nature.com\/articles\/srep12625","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.nature.com\/articles\/srep12625.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,1,5]],"date-time":"2023-01-05T22:20:22Z","timestamp":1672957222000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.nature.com\/articles\/srep12625"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2015,7,27]]},"references-count":29,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2015,10,16]]}},"alternative-id":["BFsrep12625"],"URL":"https:\/\/doi.org\/10.1038\/srep12625","relation":{},"ISSN":["2045-2322"],"issn-type":[{"value":"2045-2322","type":"electronic"}],"subject":[],"published":{"date-parts":[[2015,7,27]]},"assertion":[{"value":"19 March 2015","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"29 June 2015","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"27 July 2015","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"The authors declare no competing financial interests.","order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"12625"}}