{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T20:56:02Z","timestamp":1792616162062,"version":"4.5.0"},"reference-count":73,"publisher":"Elsevier BV","license":[{"start":{"date-parts":[[2026,11,1]],"date-time":"2026-11-01T00:00:00Z","timestamp":1793491200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.elsevier.com\/tdm\/userlicense\/1.0\/"},{"start":{"date-parts":[[2026,11,1]],"date-time":"2026-11-01T00:00:00Z","timestamp":1793491200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.elsevier.com\/legal\/tdmrep-license"},{"start":{"date-parts":[[2026,11,1]],"date-time":"2026-11-01T00:00:00Z","timestamp":1793491200000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-017"},{"start":{"date-parts":[[2026,11,1]],"date-time":"2026-11-01T00:00:00Z","timestamp":1793491200000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-037"},{"start":{"date-parts":[[2026,11,1]],"date-time":"2026-11-01T00:00:00Z","timestamp":1793491200000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-012"},{"start":{"date-parts":[[2026,11,1]],"date-time":"2026-11-01T00:00:00Z","timestamp":1793491200000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-029"},{"start":{"date-parts":[[2026,11,1]],"date-time":"2026-11-01T00:00:00Z","timestamp":1793491200000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-004"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["42402258"],"award-info":[{"award-number":["42402258"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["U24A20597"],"award-info":[{"award-number":["U24A20597"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004607","name":"Natural Science Foundation of Guangxi Province","doi-asserted-by":"publisher","award":["2024GXNSFBA010127"],"award-info":[{"award-number":["2024GXNSFBA010127"]}],"id":[{"id":"10.13039\/501100004607","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004607","name":"Natural Science Foundation of Guangxi Province","doi-asserted-by":"publisher","award":["2024GXNSFDA010055"],"award-info":[{"award-number":["2024GXNSFDA010055"]}],"id":[{"id":"10.13039\/501100004607","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["elsevier.com","sciencedirect.com"],"crossmark-restriction":true},"short-container-title":["Environmental Research"],"published-print":{"date-parts":[[2026,11]]},"DOI":"10.1016\/j.envres.2026.125870","type":"journal-article","created":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T23:36:27Z","timestamp":1791329787000},"page":"125870","update-policy":"https:\/\/doi.org\/10.1016\/elsevier_cm_policy","source":"Crossref","is-referenced-by-count":0,"special_numbering":"P2","title":["Nitrate accumulation and transformation processes within a karst conduit system: Insights from hydrochemistry, stable isotopes, metagenomics, and tracer tests"],"prefix":"10.1016","volume":"309","author":[{"given":"Hui","family":"Dong","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0321-172X","authenticated-orcid":false,"given":"Kun","family":"Ren","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiacheng","family":"Lan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cong","family":"Peng","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaodong","family":"Pan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chun","family":"Tu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chen","family":"Song","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenping","family":"Zhang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jianwen","family":"Cao","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"78","reference":[{"issue":"11","key":"10.1016\/j.envres.2026.125870_bib1","doi-asserted-by":"crossref","first-page":"365","DOI":"10.4319\/lom.2004.2.365","article-title":"Optimization of DNA extraction for quantitative marine bacterioplankton community analysis","volume":"2","author":"Bostr\u00f6m","year":"2004","journal-title":"Limnol Oceanogr. Methods"},{"key":"10.1016\/j.envres.2026.125870_bib2","doi-asserted-by":"crossref","first-page":"153","DOI":"10.1016\/B978-0-12-407247-3.00003-2","article-title":"The role of nitrate in human health","volume":"119","author":"Bryan","year":"2013","journal-title":"Adv. Agron."},{"key":"10.1016\/j.envres.2026.125870_bib5","doi-asserted-by":"crossref","DOI":"10.1016\/j.scitotenv.2022.154554","article-title":"Shallow groundwater fluctuation: an ignored soil N loss pathway from cropland","volume":"828","author":"Chen","year":"2022","journal-title":"Sci. Total Environ."},{"issue":"1\u20134","key":"10.1016\/j.envres.2026.125870_bib3","doi-asserted-by":"crossref","first-page":"367","DOI":"10.1016\/j.jhydrol.2005.11.007","article-title":"Use of 18O, 2H and 15N to identify nitrate contamination of groundwater in a wastewater irrigated field near the city of Shijiazhuang, China","volume":"326","author":"Chen","year":"2006","journal-title":"J. Hydrol."},{"key":"10.1016\/j.envres.2026.125870_bib6","doi-asserted-by":"crossref","DOI":"10.1016\/j.watres.2024.121105","article-title":"Spatiotemporal successions of N, S, C, Fe, and as cycling genes in groundwater of a wetland ecosystem: enhanced heterogeneity in wet season","volume":"251","author":"Chen","year":"2024","journal-title":"Water Res."},{"key":"10.1016\/j.envres.2026.125870_bib7","doi-asserted-by":"crossref","first-page":"188","DOI":"10.1016\/j.agee.2015.01.011","article-title":"Evaluation of the stable isotope signatures of nitrate to detect denitrification in a shallow groundwater system in New Zealand","volume":"202","author":"Clague","year":"2015","journal-title":"Agric. Ecosyst. Environ."},{"key":"10.1016\/j.envres.2026.125870_bib8","doi-asserted-by":"crossref","first-page":"109","DOI":"10.1038\/s43016-022-00657-x","article-title":"Expanding agroforestry can increase nitrate retention and mitigate the global impact of a leaky nitrogen cycle in croplands","volume":"4","author":"Elrys","year":"2023","journal-title":"Nat. Food"},{"issue":"11","key":"10.1016\/j.envres.2026.125870_bib9","doi-asserted-by":"crossref","first-page":"945","DOI":"10.1038\/nclimate2425","article-title":"The global groundwater crisis","volume":"4","author":"Famiglietti","year":"2014","journal-title":"Nat. Clim. Change"},{"key":"10.1016\/j.envres.2026.125870_bib10","series-title":"Karst Hydrogeology and Geomorphology","author":"Ford","year":"2007"},{"key":"10.1016\/j.envres.2026.125870_bib11","article-title":"Tracing groundwater nitrate sources in an intensive agricultural region integrated of a self-organizing map and end-member mixing model tool","volume":"14","author":"Gao","year":"2024","journal-title":"Sci. Rep."},{"key":"10.1016\/j.envres.2026.125870_bib12","doi-asserted-by":"crossref","first-page":"533","DOI":"10.1007\/s00254-007-0665-2","article-title":"Major ions in typical subterranean rivers and their anthropogenic impacts in southwest karst areas, China","volume":"53","author":"Guo","year":"2007","journal-title":"Environ. Geol."},{"issue":"4","key":"10.1016\/j.envres.2026.125870_bib13","doi-asserted-by":"crossref","first-page":"2637","DOI":"10.1128\/AEM.72.4.2637-2643.2006","article-title":"Cultivation of denitrifying bacteria: optimization of isolation conditions and diversity study","volume":"72","author":"Heylen","year":"2006","journal-title":"Appl. Environ. Microbiol."},{"key":"10.1016\/j.envres.2026.125870_bib14","doi-asserted-by":"crossref","DOI":"10.1016\/j.watres.2019.115348","article-title":"Quantification of nitrate fate in a karst conduit using stable isotopes and numerical modeling","volume":"170","author":"Husic","year":"2020","journal-title":"Water Res."},{"key":"10.1016\/j.envres.2026.125870_bib15","doi-asserted-by":"crossref","DOI":"10.1029\/2021JG006454","article-title":"Seasonality of recharge drives spatial and temporal nitrate removal in a karst conduit as evidenced by nitrogen isotope modeling","volume":"126","author":"Husic","year":"2021","journal-title":"J. Geophys. Res-Biogeo."},{"key":"10.1016\/j.envres.2026.125870_bib16","doi-asserted-by":"crossref","first-page":"23002","DOI":"10.1007\/s11356-020-08759-4","article-title":"Influences of seawater intrusion and anthropogenic activities on shallow coastal aquifers in Sri Lanka: evidence from hydrogeochemical and stable isotope data","volume":"27","author":"Jayathunga","year":"2020","journal-title":"Environ. Sci. Pollut. Res."},{"key":"10.1016\/j.envres.2026.125870_bib17","doi-asserted-by":"crossref","first-page":"586","DOI":"10.1016\/j.envpol.2017.06.100","article-title":"Quantitative identification of nitrate pollution sources and uncertainty analysis based on dual isotope approach in an agricultural watershed","volume":"229","author":"Ji","year":"2017","journal-title":"Environ. Pollut."},{"key":"10.1016\/j.envres.2026.125870_bib18","doi-asserted-by":"crossref","first-page":"123","DOI":"10.1007\/s11270-009-0229-z","article-title":"Effects of land use on hydrochemistry and contamination of Karst groundwater from nandong underground river system","volume":"210","author":"Jiang","year":"2010","journal-title":"China. Water. Air. Soil. Poll."},{"key":"10.1016\/j.envres.2026.125870_bib19","doi-asserted-by":"crossref","first-page":"7676","DOI":"10.1021\/es901502t","article-title":"Human impacts on karst groundwater contamination deduced by coupled nitrogen with strontium isotopes in the nandong underground river system in Yunan, China","volume":"43","author":"Jiang","year":"2009","journal-title":"Environ. Sci. Technol."},{"key":"10.1016\/j.envres.2026.125870_bib20","doi-asserted-by":"crossref","DOI":"10.1016\/j.scitotenv.2020.144555","article-title":"Reference ion method: a simple and fast method for quantitatively identifying the source of nitrate and denitrification rate in groundwater","volume":"769","author":"Ke","year":"2021","journal-title":"Sci. Total Environ."},{"key":"10.1016\/j.envres.2026.125870_bib21","series-title":"Isotope Tracers in Catchment Hydrology","first-page":"519","article-title":"Tracing nitrogen sources and cycling in catchments","author":"Kendall","year":"1998"},{"key":"10.1016\/j.envres.2026.125870_bib22","doi-asserted-by":"crossref","first-page":"4913","DOI":"10.5194\/bg-11-4913-2014","article-title":"Nitrate source identification in the Baltic Sea using its isotopic ratios in combination with a Bayesian isotope mixing model","volume":"11","author":"Korth","year":"2014","journal-title":"Biogeosciences"},{"key":"10.1016\/j.envres.2026.125870_bib25","doi-asserted-by":"crossref","DOI":"10.1016\/j.envres.2025.121065","article-title":"New insights into nitrate sources and transformations in riparian groundwater of a sluice-controlled river: an integrated approach using major ions, stable isotopes and microbial gene methods","volume":"271","author":"Li","year":"2025","journal-title":"Environ. Res."},{"issue":"5","key":"10.1016\/j.envres.2026.125870_bib23","doi-asserted-by":"crossref","first-page":"1288","DOI":"10.1002\/2015JG003121","article-title":"Chemical weathering and the role of sulfuric and nitric acids in carbonate weathering: Isotopes(13C, 15N, 34S, and 18O) and chemical constraints","volume":"121","author":"Li","year":"2016","journal-title":"J. Geophys. Res-Biogeo."},{"key":"10.1016\/j.envres.2026.125870_bib24","doi-asserted-by":"crossref","DOI":"10.1128\/AEM.01232-10","article-title":"Changes in the structure and function of microbial communities in drinking water treatment bioreactors upon addition of phosphorus","volume":"76","author":"Li","year":"2010","journal-title":"Appl. Environ. Microbiol."},{"key":"10.1016\/j.envres.2026.125870_bib26","doi-asserted-by":"crossref","DOI":"10.1016\/j.envpol.2020.115947","article-title":"Characterization of the hydrochemistry of water resources of the Weibei Plain, Northern China, as well as an assessment of the risk of high groundwater nitrate levels to human health","volume":"268","author":"Liu","year":"2021","journal-title":"Environ. Pollut."},{"key":"10.1016\/j.envres.2026.125870_bib28","doi-asserted-by":"crossref","first-page":"58","DOI":"10.1038\/s43247-025-02016-7","article-title":"Chronic nitrogen legacy in the aquifers of China","volume":"6","author":"Liu","year":"2025","journal-title":"Commun. Earth Environ."},{"key":"10.1016\/j.envres.2026.125870_bib27","doi-asserted-by":"crossref","first-page":"891","DOI":"10.1038\/s41893-024-01369-9","article-title":"Impact of groundwater nitrogen legacy on water quality","volume":"7","author":"Liu","year":"2024","journal-title":"Nat. Sustain."},{"key":"10.1016\/j.envres.2026.125870_bib29","doi-asserted-by":"crossref","DOI":"10.1016\/j.agwat.2026.110728","article-title":"Rainfall-driven pathway switching reorganizes nitrate transport and transformation in a terrace-ditch-pond system","volume":"335","author":"Ma","year":"2026","journal-title":"Agric. Water Manag."},{"key":"10.1016\/j.envres.2026.125870_bib30","doi-asserted-by":"crossref","DOI":"10.1111\/j.1745-6584.2008.00499.x","article-title":"Using nitrate to quantify quick flow in a karst aquifer","volume":"47","author":"Mahler","year":"2009","journal-title":"Ground Water"},{"key":"10.1016\/j.envres.2026.125870_bib31","doi-asserted-by":"crossref","DOI":"10.1016\/j.jhydrol.2023.129643","article-title":"Towards a better understanding of time-lags in karst aquifers by combining hydrological analysis tools and dye tracer tests. Application to a binary karst aquifer in southern Spain","volume":"621","author":"Mart\u00edn-Rodr\u00edguez","year":"2023","journal-title":"J. Hydrol."},{"key":"10.1016\/j.envres.2026.125870_bib32","doi-asserted-by":"crossref","first-page":"2119","DOI":"10.5194\/hess-20-2119-2016","article-title":"Quantifying the influence of surface water-groundwater interaction on nutrient flux in a lowland karst catchment","volume":"20","author":"McCormack","year":"2016","journal-title":"Hydrol. Earth Syst. Sci."},{"key":"10.1016\/j.envres.2026.125870_bib33","doi-asserted-by":"crossref","first-page":"5589","DOI":"10.1021\/ac050528s","article-title":"Chemical conversion of nitrate and nitrite to nitrous oxide for nitrogen and oxygen isotopic analysis in freshwater and seawater","volume":"77","author":"McIlvin","year":"2005","journal-title":"Anal. Chem."},{"key":"10.1016\/j.envres.2026.125870_bib34","doi-asserted-by":"crossref","first-page":"85","DOI":"10.1016\/j.watres.2017.07.041","article-title":"Combining stable isotopes with contamination indicators: a method for improved investigation of nitrate sources and dynamics in aquifers with mixed nitrogen inputs","volume":"124","author":"Minet","year":"2017","journal-title":"Water Res."},{"key":"10.1016\/j.envres.2026.125870_bib35","doi-asserted-by":"crossref","DOI":"10.1016\/j.scitotenv.2020.138907","article-title":"Nitrate migration and transformations in groundwater quantified by dual nitrate isotopes and hydrochemistry in a karst world heritage site","volume":"735","author":"Ming","year":"2020","journal-title":"Sci. Total Environ."},{"key":"10.1016\/j.envres.2026.125870_bib36","doi-asserted-by":"crossref","first-page":"9335","DOI":"10.1021\/acs.est.1c06289","article-title":"Tracing the sources and fate of NO3\u2212 in the vadose zone-groundwater system of a thousand-year-cultivated region","volume":"56","author":"Niu","year":"2022","journal-title":"Environ. Sci. Technol."},{"key":"10.1016\/j.envres.2026.125870_bib37","doi-asserted-by":"crossref","first-page":"113e128","DOI":"10.1016\/S0009-2541(01)00318-7","article-title":"Determination of the sources of nitrate contamination in karst springs using isotopic and chemical indicators","volume":"179","author":"Panno","year":"2001","journal-title":"Chem. Geol."},{"issue":"3","key":"10.1016\/j.envres.2026.125870_bib38","doi-asserted-by":"crossref","DOI":"10.1371\/journal.pone.0009672","article-title":"Source partitioning using stable isotopes: coping with too much variation","volume":"5","author":"Parnell","year":"2010","journal-title":"PLoS One"},{"key":"10.1016\/j.envres.2026.125870_bib39","doi-asserted-by":"crossref","first-page":"855","DOI":"10.1016\/j.scitotenv.2013.10.043","article-title":"Assessment of sources and fate of nitrate in shallow groundwater of an agricultural area by using a multi-tracer approach","volume":"470","author":"Pasten-Zapata","year":"2014","journal-title":"Sci. Total Environ."},{"key":"10.1016\/j.envres.2026.125870_bib40","doi-asserted-by":"crossref","DOI":"10.1016\/j.scitotenv.2025.179120","article-title":"Karst water quality, source of pollution, and health risk assessment in China","volume":"973","author":"Peng","year":"2025","journal-title":"Sci. Total Environ."},{"issue":"s 1\u20132","key":"10.1016\/j.envres.2026.125870_bib41","doi-asserted-by":"crossref","first-page":"158","DOI":"10.1016\/j.jhydrol.2006.06.027","article-title":"The role of tributary mixing in chemical variations at a karst spring, Milandre, Switzerland","volume":"332","author":"Perrin","year":"2007","journal-title":"J. Hydrol."},{"issue":"11","key":"10.1016\/j.envres.2026.125870_bib42","doi-asserted-by":"crossref","first-page":"523","DOI":"10.1016\/j.tim.2012.08.001","article-title":"Archaeal and bacterial ammonia-oxidisers in soil: the quest for niche specialisation and differentiation","volume":"20","author":"Prosser","year":"2012","journal-title":"Trends Microbiol."},{"key":"10.1016\/j.envres.2026.125870_bib43","doi-asserted-by":"crossref","DOI":"10.1016\/j.watres.2021.118000","article-title":"Nitrate sources and nitrogen dynamics in a karst aquifer with mixed nitrogen inputs (Southwest China): revealed by multiple stable isotopic and hydro-chemical proxies","volume":"210","author":"Ren","year":"2022","journal-title":"Water Res."},{"key":"10.1016\/j.envres.2026.125870_bib44","doi-asserted-by":"crossref","DOI":"10.1016\/j.jhazmat.2023.132901","article-title":"Nitrate transformation and source tracking of rivers draining into the Bohai Sea using a multi-tracer approach combined with an optimized Bayesian stable isotope mixing model","volume":"463","author":"Ren","year":"2024","journal-title":"J. Hazard Mater."},{"issue":"16","key":"10.1016\/j.envres.2026.125870_bib45","doi-asserted-by":"crossref","first-page":"4215","DOI":"10.1016\/j.watres.2008.07.020","article-title":"Nitrate attenuation in groundwater: a review of biogeochemical controlling processes","volume":"42","author":"Rivett","year":"2008","journal-title":"Water Res."},{"issue":"8","key":"10.1016\/j.envres.2026.125870_bib46","doi-asserted-by":"crossref","first-page":"1693","DOI":"10.1038\/ismej.2014.252","article-title":"Relationships between protein-encoding gene abundance and corresponding process are commonly assumed yet rarely observed","volume":"9","author":"Rocca","year":"2015","journal-title":"ISME J."},{"key":"10.1016\/j.envres.2026.125870_bib48","article-title":"Contaminant transport from stormwater management areas to a freshwater karst spring in Florida: results of near-surface geophysical investigations and tracer experiments","volume":"40","author":"Shokri","year":"2022","journal-title":"J. Hydrol.: Reg. Stud."},{"key":"10.1016\/j.envres.2026.125870_bib49","doi-asserted-by":"crossref","first-page":"753","DOI":"10.1016\/j.jhydrol.2015.03.022","article-title":"Tracing freshwater nitrate sources in prealpine groundwater catchments using environmental tracers","volume":"524","author":"Stoewer","year":"2015","journal-title":"J. Hydrol."},{"key":"10.1016\/j.envres.2026.125870_bib50","doi-asserted-by":"crossref","DOI":"10.1016\/j.watres.2020.115962","article-title":"Tracking nitrate and sulfate sources in groundwater of an urbanized valley using a multi-tracer approach combined with a Bayesian isotope mixing model","volume":"182","author":"Torres-Mart\u00ednez","year":"2020","journal-title":"Water Res."},{"key":"10.1016\/j.envres.2026.125870_bib51","doi-asserted-by":"crossref","first-page":"406","DOI":"10.1016\/j.jclepro.2018.06.172","article-title":"Farmers' reasons to accept bio-based fertilizers: a choice experiment in seven different European countries","volume":"197","author":"Tur-Cardona","year":"2018","journal-title":"J. Clean. Prod."},{"key":"10.1016\/j.envres.2026.125870_bib52","doi-asserted-by":"crossref","first-page":"667","DOI":"10.1214\/20-BA1221","article-title":"Rank-normalization, folding, and localization: an improved R for assessing convergence of MCMC","volume":"16","author":"Vehtari","year":"2021","journal-title":"Bayesian Anal"},{"key":"10.1016\/j.envres.2026.125870_bib53","doi-asserted-by":"crossref","first-page":"1775","DOI":"10.5194\/bg-10-1775-2013","article-title":"Nitrification and growth of autotrophic nitrifying bacteria and Thaumarchaeota in the coastal North Sea","volume":"10","author":"Veuger","year":"2013","journal-title":"Biogeosciences"},{"issue":"1","key":"10.1016\/j.envres.2026.125870_bib54","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1016\/j.watres.2004.07.026","article-title":"Non-agricultural sources of groundwater nitrate: a review and case study","volume":"39","author":"Wakida","year":"2005","journal-title":"Water Res."},{"key":"10.1016\/j.envres.2026.125870_bib56","doi-asserted-by":"crossref","DOI":"10.1016\/j.scitotenv.2020.144616","article-title":"Radium and nitrogen isotopes tracing fluxes and sources of submarine groundwater discharge driven nitrate in an urbanized coastal area","volume":"763","author":"Wang","year":"2021","journal-title":"Sci. Total Environ."},{"issue":"12","key":"10.1016\/j.envres.2026.125870_bib55","doi-asserted-by":"crossref","first-page":"1736","DOI":"10.1039\/C8EM00445E","article-title":"Nitrate dynamics during impoundment and flood periods in a subtropical karst reservoir: Hongfeng Lake, Southwestern China","volume":"20","author":"Wang","year":"2018","journal-title":"Environ. Sci. Process. Impacts"},{"key":"10.1016\/j.envres.2026.125870_bib57","doi-asserted-by":"crossref","DOI":"10.1029\/2008JG000729","article-title":"Using nitrate dual isotopic composition (\u03b415N and \u03b418O) as a tool for exploring sources and cycling of nitrate in an estuarine system: Elkhorn Slough, Calieornia","volume":"114","author":"Wankel","year":"2009","journal-title":"J. Geophys. Res."},{"key":"10.1016\/j.envres.2026.125870_bib58","series-title":"Chemical Fact Sheets: Nitrate\/Nitrite","year":"2022"},{"key":"10.1016\/j.envres.2026.125870_bib59","doi-asserted-by":"crossref","first-page":"48661","DOI":"10.1007\/s11356-022-19277-w","article-title":"Migration, transformation and nitrate source in the lihu underground river based on dual stable isotopes of \u03b415N-NO3\u2212 and \u03b418O-NO3\u2212","volume":"29","author":"Wu","year":"2022","journal-title":"Environ. Sci. Pollut. Res."},{"key":"10.1016\/j.envres.2026.125870_bib60","doi-asserted-by":"crossref","DOI":"10.1016\/j.jhydrol.2025.132973","article-title":"Seasonal nitrate input drives the spatiotemporal variability of regional surface water-groundwater interactions, nitrate sources and transformations","volume":"655","author":"Wu","year":"2025","journal-title":"J. Hydrol."},{"key":"10.1016\/j.envres.2026.125870_bib61","doi-asserted-by":"crossref","DOI":"10.1016\/j.watres.2026.125687","article-title":"An integrated geochemical and isotopic framework for nitrate source apportionment in a shallow coastal aquifer under multiple environmental pressures","volume":"297","author":"Xiao","year":"2026","journal-title":"Water Res."},{"key":"10.1016\/j.envres.2026.125870_bib62","doi-asserted-by":"crossref","DOI":"10.1016\/j.scitotenv.2024.172248","article-title":"Tracing the impacts of ecological water replenishment on the sources and transformation of groundwater nitrate through isotope and microbial analysis","volume":"928","author":"Xu","year":"2024","journal-title":"Sci. Total Environ."},{"key":"10.1016\/j.envres.2026.125870_bib63","doi-asserted-by":"crossref","first-page":"1159","DOI":"10.1016\/j.watres.2008.12.048","article-title":"Present limitations and future prospects of stableisotope methods for nitrate source identification in surface-and groundwater","volume":"43","author":"Xue","year":"2009","journal-title":"Water Res."},{"key":"10.1016\/j.envres.2026.125870_bib64","doi-asserted-by":"crossref","first-page":"43","DOI":"10.1016\/j.envpol.2011.09.033","article-title":"Use of a Bayesian isotope mixing model to estimate proportional contributions of multiple nitrate sources in surface water","volume":"161","author":"Xue","year":"2012","journal-title":"Environ. Pollut."},{"key":"10.1016\/j.envres.2026.125870_bib66","doi-asserted-by":"crossref","DOI":"10.1016\/j.jhydrol.2023.129896","article-title":"Nitrate attenuation potential in karst conduits and aquifer matrix","volume":"624","author":"Yang","year":"2023","journal-title":"J. Hydrol."},{"key":"10.1016\/j.envres.2026.125870_bib65","doi-asserted-by":"crossref","DOI":"10.1016\/j.envpol.2020.114835","article-title":"Nitrate sources and biogeochemical processes in karst underground rivers impacted by different anthropogenic input characteristics","volume":"265","author":"Yang","year":"2020","journal-title":"Environ. Pollut."},{"key":"10.1016\/j.envres.2026.125870_bib67","doi-asserted-by":"crossref","first-page":"106","DOI":"10.1016\/j.scitotenv.2007.05.027","article-title":"Salinity of animal manure and potential risk of secondary soil salinizationthrough successive manure application","volume":"383","author":"Yao","year":"2007","journal-title":"Sci. Total Environ."},{"key":"10.1016\/j.envres.2026.125870_bib68","doi-asserted-by":"crossref","first-page":"226","DOI":"10.1016\/j.envpol.2012.07.027","article-title":"Integrated assessment on groundwater nitrate by unsaturated zone probing and aquifer sampling with environmental tracers","volume":"171","author":"Yuan","year":"2012","journal-title":"Environ. Pollut."},{"issue":"8","key":"10.1016\/j.envres.2026.125870_bib69","doi-asserted-by":"crossref","first-page":"1883","DOI":"10.1002\/hyp.10302","article-title":"Sources and transport of nitrate constrained by the isotopic technique in a karst catchment: an example from Southwest China","volume":"29","author":"Yue","year":"2015","journal-title":"Hydrol. Process."},{"key":"10.1016\/j.envres.2026.125870_bib70","doi-asserted-by":"crossref","first-page":"8537","DOI":"10.1038\/s41598-017-08756-7","article-title":"Tracing nitrate sources with dual isotopes and long term monitoring of nitrogen species in the Yellow River, China","volume":"7","author":"Yue","year":"2017","journal-title":"Sci. Rep."},{"key":"10.1016\/j.envres.2026.125870_bib72","doi-asserted-by":"crossref","DOI":"10.1016\/j.envpol.2020.115004","article-title":"Identifying the critical nitrogen fertilizer rate for optimum yield and minimum nitrate leaching in a typical field radish cropping system in China","volume":"268","author":"Zhang","year":"2021","journal-title":"Environ. Pollut."},{"key":"10.1016\/j.envres.2026.125870_bib73","doi-asserted-by":"crossref","DOI":"10.1016\/j.jhydrol.2020.125803","article-title":"Antecedent rainfall and land use controlling the fate of nitrogen in karst urban rivers, elucidated by an isotopic approach","volume":"592","author":"Zhang","year":"2021","journal-title":"J. Hydrol."},{"key":"10.1016\/j.envres.2026.125870_bib74","article-title":"Vertical migration of multi-source nitrates driven by multiple water inputs in groundwater based on combined nitrogen-oxygen and hydrogen-oxygen stable isotopes","volume":"501","author":"Zhang","year":"2026","journal-title":"J. Hazard Mater."},{"key":"10.1016\/j.envres.2026.125870_bib75","doi-asserted-by":"crossref","DOI":"10.1016\/j.jhydrol.2025.133442","article-title":"Nitrogen response and transformation processes in karst water system using bacterial indicators","volume":"660","author":"Zhao","year":"2025","journal-title":"J. Hydrol."},{"issue":"4","key":"10.1016\/j.envres.2026.125870_bib76","first-page":"533","article-title":"Cell biology and molecular basis of denitrification","volume":"61","author":"Zumft","year":"1997","journal-title":"Microbiol. Mol. Biol. Rev."}],"container-title":["Environmental Research"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.elsevier.com\/content\/article\/PII:S0013935126022024?httpAccept=text\/xml","content-type":"text\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/api.elsevier.com\/content\/article\/PII:S0013935126022024?httpAccept=text\/plain","content-type":"text\/plain","content-version":"vor","intended-application":"text-mining"}],"deposited":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T20:26:57Z","timestamp":1792614417000},"score":1,"resource":{"primary":{"URL":"https:\/\/linkinghub.elsevier.com\/retrieve\/pii\/S0013935126022024"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,11]]},"references-count":73,"alternative-id":["S0013935126022024"],"URL":"https:\/\/doi.org\/10.1016\/j.envres.2026.125870","relation":{},"ISSN":["0013-9351"],"issn-type":[{"value":"0013-9351","type":"print"}],"subject":[],"published":{"date-parts":[[2026,11]]},"assertion":[{"value":"Elsevier","name":"publisher","label":"This article is maintained by"},{"value":"Nitrate accumulation and transformation processes within a karst conduit system: Insights from hydrochemistry, stable isotopes, metagenomics, and tracer tests","name":"articletitle","label":"Article Title"},{"value":"Environmental Research","name":"journaltitle","label":"Journal Title"},{"value":"https:\/\/doi.org\/10.1016\/j.envres.2026.125870","name":"articlelink","label":"CrossRef DOI link to publisher maintained version"},{"value":"article","name":"content_type","label":"Content Type"},{"value":"\u00a9 2026 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.","name":"copyright","label":"Copyright"}],"article-number":"125870"}}