Production and emission of phosphine gas from wetland ecosystems

Availableonlineatwww.sciencedinect.conScience DirectJoumal of Emvironmental Sciences 2010, 22(9)1309-1311Production and emission of phosphine gas from wetland ecosystemsRui Zhang Xiaorong Wang,lang Gag/BChao Han, Xueyuan Gu, Jinju Geng,, Yuning Hong1. State Key Laboratory of Pollution Control and Resource Reuse, School of the Evironment, Nanjing UniversityNanying210093,ChinaE-mail:automany@163.com2. School of Chemistry and Ermvirormental Science, Nanjing Normal University, Nanjing 210097, ChinaReceived 20 October 2009; revised 23 December 2009; accepted 12 Jauary 2010AbstractPhosphine is a part of an atmospheric link of phosphorus cycle on earth, which could be an important pathway for phosphorustransport in environment. Wetland ecosystems are important locations for global biogeochemical phosphorus cycle. In this study,production and emission fluxes of free phosphine from four wetlands types in southern China were observed in different seasons. Theresults showed that the concentration of phosphine liberated from wetlands was at pg/m-ng/mlevel. The emission concentrations ofdifferent wetlands followed the sequence: paddy field (51.83#3.06)ng/m> marsh(4654#20.55)ng/m> lake(37.05# 22.74)ng>coastal wetland (1.71+0.73)ng/m, the positive phosphine emission flux occurred in rice paddy field (6.67+5.18)ng/(m?hr)andmarsh(6.23+ 26.9)ng/(m2.hr), while a negative phosphine flux of (-13 11+ 35.04)ng/(m.hr)was observed on the water-air interfacof Lake Taihu, suggesting that paddy field and marsh may be important sources for phosphine gas in atmosphere, while lake may be asink of atmospheric phosphine gas during the sampling period. Atmospheric phosphine levels and emission flux from Yancheng marshand rice paddy field varied in different seasons and vegetational zones. Both diffusion resistance in aqueous phase and temperature weredominating factors for the production and transportation of phosphine to atmosphereKey words: phosphine; flux; wetland ecosystemsDOL101016S10010742(09)60255-2Phosphine(PH3), a highly toxic reducing gas, is proved Nature Reserve, along the southeast coast of the Yellowto be a ubiquitous trace gas in atmosphere and a signifi- Sea, is the largest natural coastal wetland with typicalcant constituent of the phosphorus biogeochemistry cycle floral succession. According to the salinity of surface waterGeng et al., 2005a: Zhu et al, 2009). Large areas of and vegetation types, the investigation was divided intowetlands may be major sources responsible for the emis- four typical zones: Mudflat zone, Suaeda glauca Bge zone,sion of phosphine(Devai and Delaune, 1995; Han et al., Spartina alterniflora zone and Reed zone. Gas emission2000: Liu et al, 1999 Niu et al 2004; Zhu et al., 2006), from four zones was collected in four seasons.producing enough PH3 into the atmosphere to influence Lake Taihu(31%21N, 12010E), a typical shallorthe biogeochemical cycles of phosphorus(Glindemann et freshwater lake, located in one of the most densely pop-al, 2005). However, the source and distribution of PH3 in ulated and developed areas of China. In recent years, largenatural environment still remain unclear. So far, limited amounts of municipal sewage from surrounding cities areresearch has been conducted to investigate the fate of dischargee lake, causing severe lake eutrophica-PH3 gas in various wetland ecosystems. Monitoring the tion. Thewere collected in spring, 2009 at theconcentrations and fluxes of PH, gas in different sources site of Meiliang Bay, where blue algal bloom happare of prime important to understand the sources and sinks frequentlyof PH3 in environment. In this article, four typical wet- Coastal zone of Southwest Yellow Sea(3145land ecosystems including paddy field, swamps, numerous 3340N, 121-122 22'E), was chosen as representativeeutrophic lakes and coastal shallow, were investigated of shallow coastal marsh. The investigation area has ato explain the natural volatile phosphorus emissions and lot of biologically active mariculture areas, with a largetransports in natural environment, and the concentrations amount of organic mariculture sewage input, as a possibleand fluxes of PH3 gas from such wetlands were systemicmonitored for the first time中国煤化工 Sampling sites inlong the SouthwestFour typical wetland ecosystems in Jiangsu Province, YelloC N M H Ganyungang HarborEastern China, were selected in this study. Yancheng Old Yellow River mouth, Sheyang River mouth,RadialCorrespondingauthor.E-mail:jigeng@nju.du.cntidal sand ridges, Lusi Harbor and Yangtze River mouth.Measurements were conducted from 1st December 2007 Lake Taihu and shallow sea. The concentrations of PH3 into 26th February, 2008marsh and paddy field are also much higher than that inA typical paddy field in Jiangdu, was chosen aslake and shallow sea area, suggesting that vegetationtificial marsh. Samples were collected from June to accelerate the emission of phosphine into the atmosplOctober 2008, covering all the paddy growth stages: before Han et al. (2000)indicated that PHy could be transptransplanting, transplanting, late tillering, jointing, head- through the vascular bundle into paddy stemsing, flowering, milk and ripeningA seasonal variation of PH3 in different zones ofThe PH3 samples in atmosphere above the shallow sea Yancheng swamp wetland is shown in Table 1. The highestarea were sucked from the outside through stainless-steel PH3 level occurs in summer, followed in spring, autumntube installed to the sampler and stored in a 0.5 L Tedlar and winter, indicating that temperature may be a majorgas bag with polypropylene valves(Glindemann et al., factor affecting PH3 generation. In summer, bacteria are2003). To avoid the impacts of anthropogenic factors and more active and increasing temperature could accelerateresearch ship itself, air samples were collected from the the disintegration of soil organism and the mineralizationupwind on the fore. All air sample Tedlar bags were pre- of N and P(Glindemann et al., 1996; Liu et al., 1999;served under-20 C in the dark until laboratory analysis. Song et al., 2006). A significant difference is observed forIt has been proved that atmospheric PH3 concentration the average PH3 concentrations at four sites with differentwas stable under such preservation conditions(Zhu et al., soils and vegetation characteristics. The maximum atme2007)spheric PH3 level is measured in Suaeda glauca Bge zone,A closed-chamber method was adopted to measure the followed by in Spartina alterniflora site and mudflat zone;PH, emission in the swamp lake and paddy field( Han et and the minimum is found in reed zone Water phase playsal, 2000).In this study, the stainless-steel chamber (50 an important role in slowing down the diffusion of PHycm x 50 cm), which could avoid PH3 photodegradation from soil to atmosphere( Eismann et al., 1997). Therefore,were wrapped with quilt to maintain the temperature inside PH, emission level in reed zone covered with water aroundthe chamber During sampling in swamp and paddy field, the whole year is much lower than that in other three zonesthe opened-bottom chamber(50 cm x 50 cm x 100 cm) with less water or without waterequipped with two fans and a water groove on the top The two PH3 level peaks are observed at late tilleringwas inserted into soils for 20 cm. Air sample inside the stage and jointing stage, with the values of(105.3+ 125.9chamber was taken at 10 min intervals by using a 60-mL ng/m and(116. 3+ 12.9)ng/m, respectively, whereasplastic syringe for one hour. Before sampling, fans were the lowest value is measured before transplanting stageturned on to stir the air in the chamber. As for the lake, a In general, PH3 concentrations in flourishing stages areshorter chamber(50 cm x 30 cm x 50 cm)equipped with higher than those in slowly growing stages. A significantan inner tube was used to collect the atmospheric above the positive correlation is found between temperature and PH3water. Three parallel experiments were conducted. All air concentration(r=0.57, n=32, P<0.005)samples were stored in 0.5 L Tedlar gas bags in the dark Positive PH3 flux is found in rice paddy field anduntil laboratory analysis within 48 hr.swamp, while negative PH3 flux is observed in lakeGas samples in 50 mL syringes were purged with indicating that paddy field and marshbe importantoure nitrogen into two successive capillary cryotraps after places responsible for PH3 production and emission todrying. Then, the rich PH, desorbed into a gas chromato- atmosphere, while lake may be served as a pool of at-graph(Agilent 4890D, USA)for all PH3 determinations, mospheric PH3 gas Phosphine might be an important gaswhich was equipped with a capillary column(cross- pathway for phosphorus transport in eutrophicated lakes.linked 5% Ph MeSilicone, 25 m x 0.2 mm x 0.33 um The negative flux of PH] in the lake also may be the reasonfilm thickness, Hewlett-Packard, USA)and a thermo- of the low atmospheric PH3 concentration.ionicnitrogen-phosphorus-detector.Swamp is a source of atmospheric PH3, showing aPH, is found in all samples, ranging from(0. 14* distinct spatial and temporal variation. Among the four0.00)to(147.68+ 50.94)ng/m The detected levels are different vegetation zones, the highest PHy average fuxsimilar to the results by Glindemann et al. (2005). For 60.25 ng/(m"- hr)is observed in Spartina anglica zone,different wetlands, PH, concentrations have an order of while the lowest value-4587 ng/(m hr) is in reed zone.paddy field>marsh> lake >>coastal wetland. The highest The PH3 average flux in Spartina anglica zone is higherPH3 concentration is found in marsh, while the lowest than that in mudflat zone, indicating that wetland plantsin coastal wetland. Yancheng marsh and paddy field are may be a controlling factor. PHy release from soils to themost completely covered with vegetation in contrast with atmosphere depended on a balance of the production andTable1 Seasonal variation of phosphine above different vegetation zones of marsh(ng/m)glauca Bge zoneReed zone4707±101.40中国煤化工38.59±12.75l4768±50.945507±13.6517.79±107260±089CNMHG560±2.72281±0452.26±2.042.40±241Seasonal average5153±3.597490±12.335494±2.252491±1061No 9Production and emission of phosphine gas from wetland ecosystemsdepletion processes, which can be stimulated by manures Eismann F, Glindemann D, Bergmann A, Kuschk P, 1997. Soilsor chemicals that could be produced by soil microor-as source and sink of phosphine. Chemosphere, 35: 523-ganisms, as well as by root exudates or their microbial533degradation(Hou et aL., 2009; Eismann et al., 1997). As Geng JJ, Wang Q, Jin X C, Wang XR, 2005a. Distribution ofcompared with cool seasons, the release of phosphine inorganisms in partial sediments of Lakewarm seasons is enhanced, it is likely due to the higherTaihu. Biogeochemistry, 76: 283-298temperature( Geng et al., 2005b), therefore, PH3 flux ineng JJ, Jin X C, Wang Q, Niu XJ, Wang x R, Edwards Msummer is the highest (345.31 10034)ng/(m".hr)et al., 2005b. Matrix bound phosphine formation and depleResults suggest that large areas of artificial paddy fieldstion in eutrophic lake sediment fermentation-simulation ofdifferent environmental factors. Anaerobe. 11: 273-279could be sources of phosphine emissions. PH3 fluxes inpaddy field have a fluctuation pattern. A positive emissionGlindemann D,Bergmann A,StottmeisterUGassmann G,1996flux appears at late tillering stage, jointing stage andPhosphine in the lower terrestrial troposphere. Natunwis-senschaften, 83: 131-133ripening stage. when the field is not covered with water. Glindemann D, Edwards M, Kuschk P. 2003. Phosphine gas inA significantly positive correlation between the emissionthe upper troposphere Atmosphere Emvironment, 37: 2429-flux and temperature during the whole rice growing periodis also found in the study (r= 0.51, n=32, P=0.003< Glindemann D, Edwards M, LiuJ A, Kuschk P, 2005. Phosphine0.05)in soils, sludges, biogases and atmosplAs a result, we can speculate that the PH3 gas aboveA review. Ecological Engineering, 24: 457-463marine waters and lake originates from the emission of Han S H, Zhuang Y H, Liu JA, Glindemann D, 2000. Phosphorusnearby paddy fields and swamps. Atmospheric PH3 will becycling through phosphine in paddy fields. Science af Totaloxidized into water-soluble phosphate, which precipitatesErvironment. 258: 195-203to lakes and coastal marine waters via rain(Lewis etHou L J, Chen H, Yang Y, Jiang J M, Lin X, Liu M, 2009. Oc1985). Consequently, it may contribute to lake eutrophicacurrence of matrix-bound phosphine in intertidal edimentsion or red tide in coastal waterof the Yangtze Estuary. Chemosphere, 76: 1114-1119From this study, we can draw the conclusions thLewis w M, Grant M C, Hamilton S K, 1985. Evidence thatPH, emission varies in different wetland ecosystems. Thefilterable phosphorus is a significant atmospheric link in thephosphorus cycle. Oikos, 45: 428-432.release of phosphine in study areas correlate with tem- Liu ]A, Cao H E, Zhuang Y H, Kuschk P Eismann F,Glinde-perature and water. In addition, the atmosphere can carrymann D, 1999. Phosphine in the urban air of Beijing and itsgaseous phosphorus to other places affecting phosphoruspossible sources. Water, Air and Soil Pollution, 166: 597-distribution at the global scale.AcknowledgmentsNiu xJ, Geng J J. Wang XR, Wang C H, Gu X H, Edwards Metal., 2004. Temporal and spatial distributions of phosphine inThis work was supported by the National Basic Re-Taihu lake, China. Science of Total Emvironment, 323: 169-earch Program(973)of China(No. 2008CB418003), the178.Jiangsu Natural Science Foundation(No. BK2008276), Song C H, Wang Y S, Wang Y Y, Zhao Z C, 2006.Emissionthe National Natural Science Foundation of China(Noof CO2, CH4 and N2O from freshwater marsh during21077051, 30700020), the International Foundation ofeze-thaw period in Northeast of China. Atmosphere EnScience(No. A/4425-1), and the Self-Research Subject ofironmen,40:68796885State Key Laboratory of Pollution Control and Resource Zhu R B, Kong DM, Sun LG, Geng JJ, Wang XR,GlindemannReuse. We would like to thank Long-yuan Yang fromD, 2006. Tropospheric phosphine and its sources in coastalNanjing Institute of Geography and Limnology from Chi-Antarctica. Enmvirorument Science G Technology, 40: 7656-7661nese Academy of Sciences for his friendly help with gas Zhu R B Glindemann D Kong D M, Sun LG. GengJJ,WangXR, 2007. Phosphine in the marine atmosphere along amispheric course from China to Antarctica. AtmosphereReferencesErmironment. 41: 1567-1573Zhu R B, Liu Y S, Sun J J, 2009. Stimulation of gaseouDevai l, Delaune R D, 1995. Evidence for phosphine productionphosphine production from Antarctic seabird guanos anand emission from Louisiana and Florida marsh soilsornithogenic soils. Journal of Environmental SciencesOrgnaic Geochemistry, 23: 277-279.中国煤化工CNMHG