沉積物磷形態空間分布特征及釋放風險評估——以沱江流域為例

唐金勇,尹月鵬,曹 熙,張 瑜,張 雯,3*

沉積物磷形態空間分布特征及釋放風險評估——以沱江流域為例

唐金勇1,2,尹月鵬1,2,曹 熙1,2,張 瑜1,2,張 雯1,2,3*

(1.成都理工大學生態環境學院,四川 成都 610059；2.國家環境保護水土污染協同控制與聯合修復重點實驗室(成都理工大學),四川 成都 610059；3.地質災害防治與地質環境保護國家重點實驗室(成都理工大學),四川 成都 610059)

為闡明沉積物磷賦存形態的空間分布特征及潛在釋放風險,提供更準確合適的風險評估指標, 分析了沱江干流及其支流12個樣點表層沉積物的磷賦存形態,測定了水溶性磷(WSP)及磷平衡濃度(EPC0),計算沉積物磷吸附指數(PSI)、磷吸附飽和度(DPS)及其衍生的磷釋放風險指數(ERI).結果表明,沉積物5種形態磷含量順序為:鐵/鋁結合磷(CDB-P,60.63%)>鈣磷(Ca-P,30.84%)>有機磷(OP,3.92%)>亞鐵磷(Fe(Ⅱ)-P,3.48%)>松散態磷(Loosely-P,1.13%).CDB-P是沉積物磷的主要存在形態(0.468～2.287mg/g),由上游至下游逐漸降低,這主要與上游工業污染有關.DPS、EPC0和PSI在空間分布上均呈現由上游至下游逐漸增大的趨勢,變化范圍分別為44.28%～80.39%、0.012～0.084mg/L和0.153～1.526L/g;上游大部分采樣點ERI均超過了25%;各指標綜合表明:上游存在較高的磷釋放風險.回歸分析與相關性表明,EPC0與上覆水磷、CDB-P、OP、有機質(OM)以及粒徑均呈極顯著相關性,且相關性遠高于其他指標(ERI,DPS,PSI,WSP).因此,EPC0是評估沱江流域沉積物磷釋放風險潛力更準確高效的指標,Fe/Al含量、粒徑的增加以及有機質的減少會增加磷釋放風險,因此應控制工業污染以及農業面源污染的輸入.

磷形態；空間分布；磷平衡濃度；磷釋放風險

沉積物是水生態系統中磷庫的重要組成部分,其作為營養鹽的“源”與“匯”[1],同時又是磷遷移轉化、再生的主要場所.磷是水體富營養化的重要限制因子[2-3],當湖泊、河流等水體外源磷負荷減少,內源磷負荷可能阻止其水質好轉[4],并且成為水質恢復延緩的重要原因之一[5].同時,沉積物中磷的不同形態影響磷的生物有效性[6],因此研究沉積物中磷形態含量和變化特征,有助于了解河流污染程度及地球化學信息[7].改進的SEDEX沉積物磷形態分離方法[8]將沉積物中的磷形態分為松散態磷(Loosely- P)、亞鐵磷(Fe(II)-P)、鐵/鋁結合磷(CDB-P)和有機磷(OP)5種形態.該方法能將Fe(II)結合的磷單獨提取,研究表明,缺氧沉積物結合磷的潛力歸因于Fe(II)相的出現,它們與磷直接相互作用形成Fe(II)磷酸鹽相,因此將Fe(II)-P分餾為一個獨立的磷組分,對獲取沉積物中磷的地球化學信息具有重要意義.

此外,國內外學者對沉積物中磷的污染分布及風險評價進行了大量的研究,而對于沉積物磷釋放風險評價指標沒有統一的體系標準[9].目前,磷吸附指數(PSI)和磷吸附飽和度(DPS)常被用來表征土壤磷吸附容量[10-11].除此之外,水溶性磷(WSP)因其測試方法簡單快速也被用來評估土壤磷釋放風險[12].磷平衡濃度(EPC0)是指沉積物固相與周邊水溶液中的磷酸鹽(SRP)達到吸附與解吸平衡時,水相中磷酸鹽的濃度[13-14].EPC0值越高,沉積物向水柱釋放磷的風險越大[13],廣泛用于沉積物而日益受到大家的關注.研究表明,EPC0和生物有效磷存在明顯的相關性,EPC0越高,往往生物有效磷也越高,對評價沉積物磷釋放風險有一定的參考價值[15],因此沉積物充當水體磷“源”或“匯”的功能可由EPC0估計.

本研究以四川省沱江流域(綿遠河新源大橋至流灘壩水電站,104°25′～105°23′E,28°55′～31°13′N)為研究對象,系統分析了沉積物的磷賦存形態及其含量的空間分布特征,分析了EPC0和ERI等指標,旨在深入揭示沉積物磷吸附行為的變化特征及其環境意義,闡明磷釋放風險,為其提供最佳的沉積物磷釋放風險評估指標.

1 材料與方法

1.1 樣品采集與處理

根據沱江流域水系特點,選擇了12個均勻分布于沱江上中下游具有代表性的點位(圖1).采用彼得森抓斗式采泥器采取表層沉積物,采集后將樣品置于密封的聚乙烯塑料袋中,一部分于4℃左右儲存在實驗室用于沉積物磷賦存形態及EPC0的測定,另一部分于-20℃下冷凍干燥研磨后儲存于干燥器以待后續實驗分析.

圖1 采樣點分布

1.2 實驗方法

1.2.1 理化性質測定 上覆水理化指標,包括pH值、DO,在現場用YSI多參數水質分析儀測定,流速采用流速儀測定,其他指標低溫保存帶回實驗室分析.沉積物pH值采用pH計測定,氧化還原電位(h)采用電極法測定;含水率(WC)于105℃下干燥測定[16];有機質(OM)采用燒矢重法測定[17];粒徑采用激光粒度分析儀(Mastersizer 2000)測定,并將其分為3類:黏粒(0～0.002mm)、粉粒(0.002～0.02mm)和砂粒(0.02～2mm)[18].

1.2.2 沉積物磷賦存形態的測定 使用改進的SEDEX法[8]將沉積物中的磷分為:松散結合磷(Loosely-P)、亞鐵磷(Fe(II)-P)、鐵/鋁結合磷(CDB-P)、鈣磷(Ca-P)和有機磷(OP)5類(圖2).提取液中溶解磷酸鹽使用鉬銻抗分光光度法測定[19].沉積物總磷(TPS)為5種形態磷之和.

1.2.3 等溫吸附實驗 EPC0的測定基于磷等溫吸附線.約1g(按干重)樣品分別與20mL含有濃度為0.0,0.5,1.0,5.0,10.0,15.0,25.0,50.0,75.0mg/L的磷酸鹽標準溶液(如KH2PO4)一起放入50mL聚乙烯離心管中(用于測定EPC0的新鮮沉積物需保證在7d內分析,以減少樣品變質[20])恒溫[(25±1)℃]下振蕩24h以達到平衡[21].通過測定濾液的磷濃度(EPC)與初始磷濃度的差值計算磷吸附量(SP).磷吸附等溫線由SP和EPC作圖得到.

圖2 SEDEX法流程

1.2.4 水溶性磷(WSP)濃度測定 稱取約1g(按干重)樣品于50mL含有25mL蒸餾水的聚乙烯離心管中,恒溫(25±1)℃下振蕩24h,離心后取上清液,測定濾液中磷酸鹽濃度,即為WSP[22].

1.2.5 磷吸附指數(PSI)[23]磷吸附指數計算公式如下:

式中:PSI表示磷吸附指數,L/g;和分別表示1g沉積物于含有75mg P/L的20mL磷溶液在振蕩24h達到平衡后溶液中磷的吸附量和磷平衡濃度, mg/g,mg/L.

1.2.6 磷吸附飽和度(DPS)[24]磷吸附飽和度計算公式如下:

式中:DPS表示磷吸附飽和度,%;TPS為沉積物總磷含量, mg/g;SPmax為沉積物最大磷吸附量, mg/g,由1.2.3得出.

1.2.7 磷釋放風險指數(ERI) 用黃清輝等[25]提出的ERI來評估沉積物中磷的釋放風險,計算公式如下:

式中: ERI為磷釋放風險指數,%;DPS為磷吸附飽和度,%;PSI為磷吸附指數,L/g.

1.3 數據處理

運用Excel和Origin對數據進行處理和圖表繪制,采用IBM SPSS Statistics22(IBM,USA)進行數據的Pearson相關性分析.

2 結果與討論

2.1 上覆水與沉積物理化性質分析

表1 上覆水和沉積物的理化性質

注:DO為溶解氧;h為氧化還原電位;OM為有機質.

由表1可知,流域上覆水的pH值呈中性偏堿(7.78～9.27).水體DO含量變化范圍為4.60～8.30mg/ L.沉積物pH值整體呈中性偏弱堿性(6.79～9.27),氧化還原電位(h)變化范圍為-81～48mV,沉積物呈現弱缺氧狀態.從上游至下游沉積物細顆粒(黏粒+粉粒)呈現增加的趨勢,其平均值分別為37.26%, 56.43%和61.89%,這可能因為上游流速(平均值為1.40m/s)比中下游(平均值分別為0.1, 0.19m/s)湍急.沉積物OM平均含量為7.41%(3.32%～12.16%),空間分布呈現:上游(4.3%)<中游(7.87%)<下游(10.05%).上游OM含量分布均勻(3.32%～5.08%),中游S6處于干流上游,地處成都-資陽市界處,導致其OM含量高達12.16%.下游S12處OM含量出現最大值,高達12.14%,該處水庫水體流動性較差,為OM的沉降和富集創造了有利條件.OM在空間上呈現出高度的差異性,與不同區域的污染程度以及沿程筑壩對OM的滯留有關.

2.2 上覆水與沉積物磷形態空間分布特征

上覆水總磷(TPw)、溶解態總磷(DTP)和溶解反應磷(SRP)均表現為從上游至下游降低的趨勢(圖3),變化范圍分別為0.08～0.23, 0.05～0.21和0.01～ 0.07mg/L.上游水體磷含量較高,與上游工業、城市點源污染以及農業面源污染有關,TPw最大值出現在上游S1點位,這可能是由于附近農田以及污水處理廠的排放.此外,一般認為,當TPw濃度達到0.02mg/L時,水體有可能會出現藻華[26].在本研究中,發現所有點位的TPw濃度均超過了這一臨界濃度,因此需要相關的措施來改善水中磷污染情況.

圖3 上覆水磷含量及空間分布

沉積物總磷(TPs)為1.84mg/g(0.84～2.85mg/g),空間上表現為:上游(2.45mg/g)>中游(1.12mg/g)>下游(1.12mg/g),TPs最大值出現在上游S1采樣點,最小值出現在下游S9采樣點(圖4).由于流域上游土地利用類型以旱地、水田居多,沿河畜禽、水產養殖發達,農藥化肥及飼料使用頻繁,且污水收集處理設施不健全(如采樣點S2與S4均處于城鎮下游).與世界各地TPs含量(法國克魯茲河[27]:0.51～2.29mg/g;美國卡萊爾湖[28]:0.14～1.60mg/g;黃河[29]:0.20～0.75mg/g)相比,沱江流域TPs含量均高于以上研究區域,特別是上游河段.同時,TPs濃度沿程降低,除河流水體磷的自然沉降過程外,梯級筑壩對水體磷污染物的攔截作用也不可忽略[30],Wang等[31]將沉積物的污染水平根據總磷的含量分為3級,重污染水平:TPs>1.3mg/g;中等污染水平:0.5mg/g￡TPs￡1.3mg/g,輕度污染水平:TPs<0.5mg/g.本研究中TPs平均含量為1.84mg/g,遠超沉積物重污染1.3mg/g水平線,并且TPs與TPw的空間分布相似,這表明沉積物中的磷有向上覆水體二次釋放的趨勢.

圖4 沉積物各形態磷的相對含量

圖5 沉積物磷含量及空間分布

圖6 各評價指標空間分布

沉積物各形態磷在采樣點之間存在顯著差異(圖5),說明人類活動對流域的影響.各形態磷含量占總磷百分比為:CDB-P(60.63%)>Ca-P(30.84%)>OP (3.92%)>Fe(Ⅱ)-P(3.48%)>Loosely-P (1.13%).CDB- P是沉積物磷形態的主要組分,主要指由鐵、鋁等金屬(氫)氧化物結合的磷,并能與OH-及有機配體進行交換.因此,CDB-P很容易在堿性條件或還原環境下轉化為溶解態磷[32-33]而釋放到上覆水中,最終使水質惡化.本研究中.CDB-P含量為0.468～2.287mg/g,從上游(1.648mg/g)至中游(1.268mg/g)、下游(0.557mg/g)平均含量逐漸降低,推測上游來水磷負荷輸入(S2、S3和S4點處的工業和生活污水)是影響沱江沉積物CDB-P含量的主要原因.

Ca-P主要是由自生磷灰石或碎屑巖等陸源輸入形成的一種穩定態磷,由沉積物向上覆水釋放的可能性較小,受人類活動影響不大.沉積物Ca-P含量空間變化與TPs一致,由上游(0.688mg/g) 逐漸降低至下游(0.422mg/g).沱江水體pH值總體偏堿性(7.78～9.27),上覆水中鈣離子容易吸附上覆水中的磷酸鹽從而形成Ca-P[34],導致在外部磷輸入較高的上中游沉積物中Ca-P含量比較高.

沉積物中的OP一般認為來自水生動植物殘體和農業化肥,而其中一部分OP為不穩定磷,容易隨沉積物有機物的分解礦化轉化成無機磷向上覆水中釋放.本研究沉積物OP含量變化范圍為0.019～ 0.076mg/g,其空間變化與OM一致,這與水生植物及周邊農作物殘體沖入至中下游區域有關.

Fe(Ⅱ)-P指沉積物中與磷相互作用形成的Fe(II)磷酸鹽相,是沉積物中重要的磷組分.沉積物中Fe(II)-P的穩定性對pH值、h、離子強度和天然配體等環境因素高度敏感[35-36].盡管沱江沉積物中Fe(Ⅱ)-P含量為0.034～0.111mg/g,在整個磷組分占比較低(3.48%),但隨著pH值和h的降低,Fe(II)-P極易向上覆水中釋放,特別是在表層沉積物中[37-38],因此它在沉積物當中也是一種不可忽略的磷組分.

Loosely-P作為無機磷重要的形態之一,用于浮游植物的消耗和生產循環,極易由沉積物向上覆水體釋放,其釋放量主要取決于沉積物中的環境條件(如pH值、溫度、水動力學和h).Loosely-P是本研究中含量最低的磷組分,變化范圍為0.007～ 0.030mg/g,在溫度升高或擾動條件下容易向上覆水中釋放.由于各種形態磷(Loosely-P、Fe(Ⅱ)-P、CDB-P)的生物不穩定性,因此需要高度關注這些形態的磷.

2.3 流域沉積物磷釋放風險評估

當EPC0大于SRP時,沉積物表現出釋放磷的趨勢,反之為吸附磷[39].本研究EPC0含量為0.012～ 0.084mg/L,上中下游平均值依次為0.069, 0.033和0.024mg/L.從空間分布來看,上游EPC0較高(圖6),并且其值均高于SRP,上游水體磷含量較高,導致沉積物-水界面達到磷吸附/解吸平衡時的EPC0值就越高.

ERI可將富營養化風險細分為高度風險(ERI>25%)、較高風險(20%

圖7 上覆水磷含量與各指標線性回歸分析(n=12)

DPS是反映沉積物中磷吸附量占總磷吸附量百分比的指標,可用于評價沉積物對磷的吸附能力[42].一般認為,較低的DPS表明沉積物中的磷吸附位點尚未飽和,沉積物具有較高的磷吸附能力[43],同時表明沉積物作為“匯”的可能性較大.本研究沉積物的磷吸附飽和度(DPS)為44.28%～80.39%,平均值為上游(73.71%)>中游(63.92%)>下游(54.17%),最大值在S1,最小值在S11,從空間分布上來看,上游DPS高于中下游,是由于上游污染源較多,沉積物累積了大量的外源磷輸入.其次,與我國閩江[41](7.30%～18.29%)相比,沱江流域DPS總體偏高,因此表明其沉積物具有較小的磷吸附能力和潛在的磷釋放風險.

PSI表示可溶性磷酸鹽的固定能力,代表沉積物對磷的緩沖能力,一般隨著沉積物含量的增加而增加[44-45].本研究中,沉積物PSI為0.153～1.526L/g,空間變化與DPS相反,由上游至下游依次增加(平均值分別為0.208, 0.389, 0.727L/g),最大值出現在S9,最小值出現在S2,這是由于上游細顆粒相對較少,對磷的吸附能力較弱.另一方面,上游OM含量相對較低,而OM在一定程度上能很好的與磷絡合,并將其固定在沉積物中.

WSP主要是用蒸餾水可提取的磷,其值越高,表明磷的釋放風險就越高[46].已有研究將該指標運用于土壤磷的流失風險分析,對沉積物而言,WSP作為生物可利用磷而極易向上覆水中釋放.本研究WSP含量為19.294mg/L(9.496～26.190mg/L),表現出上游 >中游>下游的空間分布特征.上游細顆粒和OM含量占比較低,導致沉積物吸附的磷呈弱吸附態[47],極易向上覆水體釋放.

通過以上各指標的綜合分析,表明沱江流上游沉積物具有較高的磷釋放風險.

如圖7所示,相比ERI、DPS、PSI和WSP,EPC0與水中各形態磷相關性均最好,且EPC0與SRP的相關性(2=0.918,<0.001)顯著高于TPw(2=0.591,<0.05)和DTP(2=0.716,<0.05),表明EPC0能有效并準確地評估沱江流域沉積物-水界面磷吸附-解吸狀態,而DPS、PSI由于從沉積物飽和度和吸附能力去表征,沒有考慮磷的釋放風險[48],并且ERI作為磷釋放風險評價指標在國內外應用并不廣泛.此外,通過比較EPC0和SRP,可以估算沉積物向水柱釋放SRP的潛能,當水中SRP的濃度高于EPC0值時,沉積物表現出吸附磷的趨勢,反之為釋放磷.EPC0越大,則釋放風險越高[49],進一步對比分析上覆水中的SRP和EPC0濃度(圖8),上游EPC0均大于SRP,可能暗示上游沉積物磷釋放風險更大.

圖8 EPC0風險評估示意

黑色箭頭表示沉積物向上覆水釋放磷:EPC0>SRP,灰色箭頭表示沉積物吸附磷: EPC0

2.4 影響內源磷釋放的沉積物組分

如表2所示:EPC0與CDB-P、OP、OM、粉粒和砂粒均存在極顯著的相關性,且相關性高于其他指標,表明沉積物磷釋放行為與這些組分密切相關.

EPC0與CDB-P的極顯著正相關性(=0.78,<0.01)表明CDB-P是可能增加沉積物磷釋放風險的主要磷組分.一般來說,(氫)氧化物對鐵、鋁有很強的吸附能力,CDB-P可與OH-及其他在堿性條件下可溶解的無機磷化合物交換.CDB-P為本研究主要的磷形態之一,因此很容易受到環境的改變向上覆水中釋放.而鐵結合磷會隨著pH值的降低更多地向上覆水中釋放,隨后被初級生產者消耗[50].此外,當氧氣充足時,磷會被三價鐵吸收,但如果水處于缺氧狀態,三價鐵會還原為二價鐵,導致磷和鐵從沉積物中釋放出來[38].

EPC0與OP、OM的極顯著負相關性(分別為-0.803、-0.746,<0.01)表明,OM對沉積物OP的吸附釋放有很大的影響.OP因分解緩慢而較為穩定,與大型植物、浮游植物和陸生有機碎屑的沉積關系更密切[51],OM中的腐殖質可以形成膠膜粘覆在粘土礦物、鐵、鋁氧化物以及碳酸鈣等無機物內外表面,形成無機有機復合體,成為沉積物-水界面對磷遷移轉化的重要自然膠體.此外,OM釋放的氫離子可使礦物表面基團質子化而有利于磷的吸附,并且腐殖質能和鐵/鋁等礦物形成有機或無機復合體,提供了重要的磷吸附位點,從而增強了對磷的吸附[52],不易向上覆水中釋放.綜上表明:OM組分的增加將降低沱江沉積物OP的釋放風險[53].

此外,EPC0與粉粒、砂粒也呈極顯著相關性(分別為-0.727、0.719,<0.01).粒徑是影響沉積物磷釋放的重要因素,砂粒具有典型的很低的磷吸附點位,因為它的非晶態鐵和鋁濃度較低[54],吸附在上面的磷也容易向上覆水中釋放.

表2 理化參數間的相關性分析(n=12)

注:**在0.01級別(雙尾),相關性顯著;*在0.05級別(雙尾),相關性顯著.

3 結論

3.1 研究區TPw、DTP和SRP含量為分別為0.08～ 0.23, 0.05～0.21和0.01～0.07mg/L.水體污染程度呈現上游>中游>下游的空間分布特征,這可能是由于上游污染源較多,外源磷輸入導致水體總磷含量較高.

3.2 研究區TPs含量為0.84～2.85mg/g,空間分布呈現由上游向下游遞減的趨勢,上游TPs污染表現為重度污染(2.45mg/g).沉積物各形態磷含量為: CDB-P(60.63%)>Ca-P(30.84%)>OP(3.92%)>Fe (Ⅱ)-P(3.48%)>Loosely-P(1.13%),在水平空間分布上,CDB-P與TPs空間變化趨勢一致,這主要與上游工業污染有關,表明沉積物吸附的磷主要以CDB-P的形式貯存在沉積物中,并且其含量越高,越容易向上覆水中釋放.

3.3 由EPC0、ERI、DPS、PSI和WSP綜合評估,沱江流域上游沉積物表現為較高的磷釋放風險. EPC0與SRP、CDB-P、OP、OM以及粒徑均呈極顯著相關性(2分別為0.918, 0.780, -0.803, -0.746),且相關性遠高于其他指標(ERI,DPS,PSI, WSP),因此,EPC0是評估沱江流域沉積物磷釋放風險潛力更準確高效的指標.同時,EPC0與CDB-P、砂粒的極顯著正相關性,并與OP、OM、砂粒的極顯著負相關性表明了沱江流域沉積物磷主要受到Fe/Al金屬(氫)氧化物、OM及粒徑的控制.當Fe/Al含量和砂粒增加以及OM含量減少時,磷釋放風險會顯著增加,因此應控制工業污染以及農業面源污染的輸入.

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Spatial distribution characteristics and release risk assessment of phosphorus forms in sediments: A case study of the Tuojiang River Basin.

TANG Jin-yong1,2, YIN Yue-peng1,2, CAO Xi1,2, ZHANG Yu1,2, ZHANG Wen1,2,3*

(1.College of Environment and Ecology, Chengdu University of Technology, Chengdu 610059, China；2.State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil and Water Pollution (SEKL-SW), Chengdu University of Technology, Chengdu 610059, China；3.State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, China)., 2022,42(9)：4264～4273

In order to clarify the spatial distribution characteristics of the phosphorus (P) in sediments and provide more accurate and suitable indicators for assessing P release risk, samples of surface sediments were taken from 12 sites in the main stream of the Tuojiang River and its tributaries for determining water-soluble phosphorus (WSP), equilibrium P concentration (EPC0), sediment P adsorption index (PSI) and adsorption saturation (DPS), and the derived P release risk index (ERI). The results show that the order of the P contents in the five forms of sediments is as follows: iron/aluminum combined P (CDB-P,60.63%) > calcium P (Ca-P, 30.84%) > organic P (OP, 3.92%) > ferrous P (Fe(Ⅱ)-P), 3.48%) > loosely P (Loosely-P, 1.13%). CDB-P is the main form of sediment P (0.468～2.287mg/g)and decreases gradually from the upstream to the downstream, which is mainly related to upstream industrial pollution. The spatial distribution of DPS, EPC0and PSI tends to gradually increase with downstream, varying from 44.28% to 80.39%, 0.012 to 0.084mg/L and 0.153 to 1.526L/g, respectively. ERI exceeded 25% at the most upstream sampling sites, indicating a higher risk of P release in the upstream. Regression analysis and correlation show that EPC0 and the overlying water P, CDB-P, OP, OM, and particle size were significantly correlated. Therefore, EPC0can be thought to be a more accurate and efficient indicator for assessing the potential of P release from sediments in the Tuojiang River Basin. An increase in Fe/Al content, particle size, and the reduction of organic matter will elevate the P release risk, so the input of industrial pollution and agricultural non-point source pollution should be controlled.

phosphorus forms；spatial distribution；phosphorus equilibrium concentration；phosphorus release risk

X171

A

1000-6923(2022)09-4264-10

2021-12-31

國家自然科學基金資助項目(42007148)

*責任作者, 教授, zhangwen2014@cdut.edu.cn

唐金勇(1995-),男,四川南充人,成都理工大學碩士研究生,主要從事水體與沉積物磷污染治理的研究.發表論文2篇.