有機(jī)無(wú)機(jī)肥配施模式對(duì)氮素淋失的影響

滕 穎，孔凡靖，陳玉成，陳思揚(yáng)，熊海靈，朱康文，楊志敏

有機(jī)無(wú)機(jī)肥配施模式對(duì)氮素淋失的影響

滕 穎1,2，孔凡靖1,2，陳玉成1,2，陳思揚(yáng)1,2，熊海靈3，朱康文4，楊志敏1,2※

（1. 西南大學(xué)資源環(huán)境學(xué)院，重慶 400716；2. 農(nóng)村清潔工程重慶市工程研究中心，重慶市生態(tài)環(huán)境農(nóng)用地土壤污染風(fēng)險(xiǎn)管控重點(diǎn)實(shí)驗(yàn)室，重慶 400716；3. 西南大學(xué)電子信息工程學(xué)院，重慶 400715；4. 重慶市生態(tài)環(huán)境科學(xué)研究院，重慶 401147）

為了探索農(nóng)田氮素淋失低風(fēng)險(xiǎn)的有機(jī)無(wú)機(jī)肥配施模式，該研究收集了331個(gè)有效農(nóng)田有機(jī)肥化肥配施數(shù)據(jù)對(duì)，分析了施肥總量、施肥結(jié)構(gòu)（有機(jī)肥替代比）、施肥時(shí)間（基追施）、有機(jī)肥種類等因素對(duì)氮素淋失的總體影響。結(jié)果表明：與單施化肥相比，有機(jī)肥配施化肥中氮素總量較低時(shí)（N<200 kg/hm2），農(nóng)田總氮（Total Nitrogen，TN）、硝態(tài)氮（NO3--N）淋失分別減少36.77%、65.05%；有機(jī)肥替代比高于70%，雖然可減少TN淋失（39.64%），但增加了溶解性有機(jī)氮（DON）淋失的風(fēng)險(xiǎn)（15.78%），尤其是動(dòng)物型有機(jī)肥替代化肥使DON淋失增加26.31%；氮肥基施可顯著降低TN、NO3--N淋失（43.58%、70.51%，<0.05）。堿性旱地土壤上有機(jī)肥配施化肥可有效抑制TN、NO3--N淋失，但增加了26.63%～42.95%的DON淋失。旱地氮素淋失以NO3--N為主，且淋失系數(shù)高于水田，提高有機(jī)肥替代比可以大幅降低旱地氮素淋失，但增強(qiáng)了DON淋失。因子重要性分析表明：有機(jī)肥替代比對(duì)TN淋失影響占主導(dǎo)作用，而施氮水平對(duì)NO3--N、DON淋失影響更為重要。因此，低施氮量、高替代比動(dòng)物型有機(jī)肥可有效減少堿性旱地土壤氮素淋失。研究結(jié)果可為有機(jī)肥配施化肥的農(nóng)田應(yīng)用提供依據(jù)。

肥料；氮素；淋失；有機(jī)肥；DON

0 引 言

氮是作物生長(zhǎng)的必需元素，施用氮肥在有效增加作物產(chǎn)量的同時(shí)，也帶來(lái)了一系列環(huán)境負(fù)面影響[1]。研究表明：作物吸收的氮素僅占總氮輸出的55%[2]，氮肥的大量使用導(dǎo)致土壤活性氮積累，過(guò)量氮素會(huì)通過(guò)地表徑流、地下淋溶、氨揮發(fā)、反硝化等途徑損失[3]。大量研究發(fā)現(xiàn)：中國(guó)旱地氮素?fù)p失多為20%～50%，水田則多為30%～70%[4]。其中，氮滲流淋失是農(nóng)業(yè)氮素?fù)p失的主要途徑，Guo等[5]研究發(fā)現(xiàn)，在玉米生長(zhǎng)季節(jié)中，氮淋失約占氮素?fù)p失的80%。大量氮素隨著降雨或灌溉進(jìn)入地下水系統(tǒng)后會(huì)導(dǎo)致水質(zhì)惡化、生物多樣性喪失[6-7]。

農(nóng)田化肥的過(guò)量施用是導(dǎo)致氮淋失的一個(gè)重要原因[8]。目前，有機(jī)肥與化肥配施已成為農(nóng)業(yè)施肥常態(tài)[9-11]，可顯著增加土壤有機(jī)質(zhì)含量，有效提高農(nóng)產(chǎn)品產(chǎn)量和品質(zhì)[12]，影響土壤氮素淋失。研究表明：在小麥-玉米輪作系統(tǒng)中，280 kg/hm2（以N計(jì)，下同）的施氮總量、30%的豬廄肥替代化肥能夠有效抑制土壤總氮（Total Nitrogen，TN）淋失[13]；180 kg/hm2的施氮總量、50%的堆肥替代化肥使得土壤硝態(tài)氮（Nitrate Nitrogen，NO3--N）淋失顯著降低[14]；但也有研究發(fā)現(xiàn)，150 kg/hm2的施氮總量、50%的綠肥替代化肥促進(jìn)了稻田土壤溶解性有機(jī)氮（Dissolved Organic Nitrogen，DON）淋失[15]。盡管前人通過(guò)整合分析發(fā)現(xiàn)：有機(jī)肥（糞便肥、常規(guī)商品有機(jī)肥）替代比（Substitution Ratio，SR）≤70%時(shí)能夠有效抑制蔬菜系統(tǒng)TN淋失[16]。Xia等[17]研究也表明：與單施化肥相比，糞便有機(jī)肥配施化肥使得TN淋失顯著降低了28.9%。但這些試驗(yàn)研究局限于單個(gè)作物系統(tǒng)，未考慮施氮水平（Nitrogen Application Level，N）、基追施行為、有機(jī)肥種類等施肥行為特征對(duì)氮淋失的總體影響。此外，DON作為土壤氮循環(huán)中的重要氮庫(kù)，是土壤中最活躍的化學(xué)氮成分[18]。許多研究發(fā)現(xiàn)，DON損失占總氮淋失的3%～56%[19-21]，然而，有機(jī)肥配施化肥對(duì)于DON淋失風(fēng)險(xiǎn)影響并不清楚，使得農(nóng)業(yè)面源污染防控具有不確定性。

為此，本文擬對(duì)作物系統(tǒng)中有機(jī)肥配施化肥的已有結(jié)果進(jìn)行整合分析，探討施肥總量、施肥結(jié)構(gòu)（有機(jī)肥替代比）、施肥時(shí)間（基追施）、有機(jī)肥種類、土壤pH、土地利用方式的變化對(duì)于氮素淋失（TN、NO3--N、DON）的影響大小與方向，核算不同施肥處理在農(nóng)業(yè)生產(chǎn)中TN、NO3--N、DON的淋失系數(shù)，分析有機(jī)肥配施化肥對(duì)于N素淋失影響的不確定性，以期為優(yōu)化施肥、減少農(nóng)田氮素淋失風(fēng)險(xiǎn)提供理論依據(jù)。

1 材料與方法

1.1 數(shù)據(jù)采集

通過(guò)業(yè)界廣泛使用的“中國(guó)知網(wǎng)”與“web of science”兩個(gè)主要數(shù)據(jù)庫(kù)檢索了截止至2022年1月發(fā)表的經(jīng)同行評(píng)議相關(guān)論文。在搜索文獻(xiàn)時(shí)，以下關(guān)鍵詞被使用：化肥（Chemical Fertilizer）、有機(jī)肥（Organic Fertilizer）、氮淋失（N Leaching）。納入整合分析中的研究必須滿足以下標(biāo)準(zhǔn)：1）分析的數(shù)據(jù)應(yīng)為淋溶液氮含量，而不是土壤氮含量。2）研究應(yīng)具有單施化肥處理（不施用有機(jī)肥），因?yàn)檫@是本文的對(duì)照處理，同時(shí)也應(yīng)包括有機(jī)肥配施化肥或單施有機(jī)肥的處理。3）研究中各個(gè)施氮處理間應(yīng)遵循等總氮量原則，且應(yīng)明確各處理的重復(fù)數(shù)。4）沒(méi)有種植作物，缺少有機(jī)肥種類、土壤性質(zhì)（包括pH、有機(jī)質(zhì)）等因素的研究應(yīng)被舍棄。5）至少有一個(gè)目標(biāo)變量（TN、NO3--N、DON）被量化。6）為避免數(shù)據(jù)重復(fù)，在不同文獻(xiàn)中同一研究地點(diǎn)與時(shí)間中所觀測(cè)到的數(shù)據(jù)只納入一次。

在提取數(shù)據(jù)過(guò)程中，采用GetData 2.2軟件識(shí)別圖片中的數(shù)值；由于部分研究沒(méi)有報(bào)道變量的標(biāo)準(zhǔn)差（Standard Deviation，SD），將給定值的6%～11%作為SD，對(duì)應(yīng)于數(shù)據(jù)庫(kù)中各自給定的SD均值[22]，這符合統(tǒng)計(jì)學(xué)中標(biāo)準(zhǔn)差的一般范圍?；谝陨蠘?biāo)準(zhǔn)，總共篩選出35篇經(jīng)同行評(píng)議文章以及331對(duì)相關(guān)數(shù)據(jù)對(duì)用于整合分析，其中22篇來(lái)自web of science，13篇來(lái)自CNKI。

1.2 數(shù)據(jù)分類

在有機(jī)肥配施化肥過(guò)程中，評(píng)估施肥行為（施氮水平、替代比、基追施行為、有機(jī)肥種類）、初始土壤pH、土地利用方式等對(duì)土壤氮淋失的影響時(shí)，為了滿足最大程度的組內(nèi)均質(zhì)化[23]，做出以下分類。施氮水平分類[16]：低施氮水平（N<200 kg/hm2）、中施氮水平（200 kg/hm2≤N<400 kg/hm2）、高施氮水平（N≥400 kg/hm2）；有機(jī)肥替代比分類[16]：低替代比（SR≤30%）、中替代比（30%7.5）；土地利用方式分類：旱地和水田。淋失系數(shù)是施氮和不施氮的處理氮淋失差除以施氮總量，以百分比表示。

表1 數(shù)據(jù)統(tǒng)計(jì)描述

1.3 數(shù)據(jù)分析

有機(jī)肥配施化肥對(duì)變量（）的影響通過(guò)自然對(duì)數(shù)進(jìn)行量化，以表示響應(yīng)比(ln RR)，其計(jì)算公式如下[24]：

lnRR=ln(X/X)（1）

式中e與c分別表示變量的處理與對(duì)照（單施化肥）的平均值。

為了更好地顯示變量的響應(yīng)大小，采用計(jì)算式（（RR-1）×100%）將響應(yīng)比轉(zhuǎn)化為百分?jǐn)?shù)形式。其中，正百分比變化表示在有機(jī)肥配施化肥條件下目標(biāo)變量增加，反之亦然。

采用Metawin 2.1軟件進(jìn)行隨機(jī)效應(yīng)meta分析，加權(quán)平均效應(yīng)值和偏差矯正的95%置信區(qū)間是通過(guò)bootstrapping過(guò)程產(chǎn)生的，其中經(jīng)過(guò)5 000次迭代[16]。如果95%置信區(qū)間沒(méi)有與0相交，則認(rèn)為有機(jī)肥配施化肥對(duì)目標(biāo)變量（）促進(jìn)或抑制效果顯著。通過(guò)分類隨機(jī)效應(yīng)分析比較了施肥行為、土壤pH、土地利用方式對(duì)土壤氮淋失影響的效應(yīng)大小（以值表示）。經(jīng)卡方檢驗(yàn)<0.05，則認(rèn)為各組間變量的效應(yīng)值均數(shù)有顯著差異。同時(shí)運(yùn)用SPSS 23軟件對(duì)有機(jī)肥配施化肥下氮素淋失（TN、NO3--N、DON）的效應(yīng)值進(jìn)行相關(guān)性分析；采用Matlab軟件依據(jù)隨機(jī)森林模型對(duì)施肥行為、土壤pH、土地利用方式等對(duì)氮素淋失的影響進(jìn)行重要性分析。

2 結(jié)果與分析

2.1 施肥行為對(duì)氮淋失的影響

與單施化肥相比，施肥行為對(duì)土壤氮淋失有明顯的影響（圖1），其中施氮水平對(duì)TN、NO3--N、DON淋失均影響顯著（<0.05）（圖1a）。低施氮水平顯著減少了氮淋失，TN、NO3--N淋失分別減少了36.77%、65.05%，而DON淋失的影響效應(yīng)值具有異質(zhì)性。同時(shí)在中、高施氮水平下，有機(jī)肥配施化肥反而增加了DON淋失，增加比例分別為32.94%、24.43%?？赡茉蚴桥c單施化肥相比，有機(jī)肥的施入增加了土壤有機(jī)碳含量，改變土壤C/N，微生物將奪取環(huán)境中的氮源[25-26]，從而促進(jìn)土壤氮固持作用，有效抑制NO3--N等無(wú)機(jī)氮淋失。此外，有機(jī)肥自身分解釋放的有機(jī)氮增加了土壤DON含量，同時(shí)DON在土壤中的遷移性較強(qiáng)[27]，隨著施氮水平的增加，土壤吸附能力達(dá)到飽和，過(guò)量的DON可能隨降雨或灌溉淋失。

有機(jī)肥配施化肥均明顯減少了TN、NO3--N淋失（圖 1b），同時(shí)有機(jī)肥替代比對(duì)TN淋失影響顯著（<0.05），高替代比使得TN淋失顯著降低了39.64%，而替代比對(duì)NO3--N淋失沒(méi)有顯著差異（=0.37）。這與Wei等[28]研究基本一致，當(dāng)有機(jī)肥替代比大于60%時(shí)，TN淋失減少了27%。高替代比能夠顯著增加土壤團(tuán)聚體[29]和總有機(jī)碳含量，從而刺激微生物活性，增強(qiáng)土壤氮素固定，有效提高氮素利用率[30]。盡管有機(jī)肥替代比對(duì)于DON淋失沒(méi)有顯著影響，但高替代比使得DON淋失增加了15.78%。這可能是因?yàn)楦咛娲妊a(bǔ)充了土壤有機(jī)碳源[31-32]，促進(jìn)溶解性有機(jī)碳和DON的生成。此外，土壤有機(jī)質(zhì)含量迅速增加，從而阻塞了土壤的吸附位點(diǎn)，促進(jìn)了溶解性有機(jī)質(zhì)的淋失[33]。

在作物生長(zhǎng)中，施肥時(shí)間對(duì)TN、NO3--N淋失存在顯著影響（<0.05）（圖1c）。氮肥作基肥一次性施入或以基追施形式在不同時(shí)期分次施入均有效抑制TN、NO3--N淋失。且當(dāng)?shù)嗜炕r(shí)，TN、NO3--N淋失抑制效果最大，分別減少了43.58%、70.51%。這可能是因?yàn)樵谵r(nóng)業(yè)活動(dòng)中，通常以有機(jī)肥作為基肥，無(wú)機(jī)氮肥作為追肥。同時(shí)，有機(jī)肥含碳量高，在作物生長(zhǎng)初期，有機(jī)肥的施入有利于減緩?fù)寥乐械V質(zhì)氮素的累積，從而減少了氮素?fù)p失。而氮肥全部作為追肥使得TN、NO3--N淋失的效應(yīng)值存在較大異質(zhì)性。氮肥作基肥和追肥分次施入則表現(xiàn)為促進(jìn)了DON淋失。這可能是因?yàn)橛袡C(jī)肥施入土壤后，短期內(nèi)土壤DON含量迅速增加，多次施肥使得DON淋失風(fēng)險(xiǎn)大。

在不同種類有機(jī)肥配施下，TN、NO3--N淋失較單施化肥均受到抑制，但組間差異不顯著（圖1d）。土壤氮素礦化速率受C/N控制[34-35]，與植物秸稈相比，糞肥C/N低[36]，在施入土壤后，氮礦化速率較快，顯著增加氮素利用率[16]，從而抑制土壤氮素淋失。有機(jī)肥種類對(duì)DON淋失變化存在顯著影響（<0.05）。其中，動(dòng)物型有機(jī)肥和其他類型有機(jī)肥使DON淋失分別增加了26.31%、26.45%。而植物型有機(jī)肥對(duì)DON淋失效果具有異質(zhì)性。研究表明[37]：沼液的施用可以促進(jìn)DON的淋失，而淋失的主要有機(jī)成分是黃腐酸、腐殖酸、可溶性微生物副產(chǎn)物等有機(jī)化合物。因此施加動(dòng)物型有機(jī)肥后，腐殖酸類有機(jī)物可能會(huì)隨降雨淋濾，導(dǎo)致DON淋失增加。

注：1）LE為低水平；ME為中水平；HE為高水平。2）BF+TF為基追施；BF為全部基施；TF為全部追施。3）AB為動(dòng)物型；PB為植物型；OT為其他。4）n為數(shù)據(jù)對(duì)個(gè)數(shù)；P為顯著性水平，P<0.05表示各組間變量的效應(yīng)值均數(shù)有顯著差異；TN為總氮；NO3--N為硝態(tài)氮；DON為溶解性有機(jī)氮，下同。

2.2 土壤pH和土地利用方式對(duì)氮淋失的影響

在不同初始土壤pH下，與單施化肥相比，有機(jī)肥配施化肥均能減少旱地、水田土壤TN、NO3--N淋失（圖2）。初始土壤pH對(duì)TN淋失影響不顯著（=0.33），但對(duì)土壤NO3--N淋失存在顯著影響（<0.05）。當(dāng)土壤pH呈中性時(shí)，有機(jī)肥配施化肥對(duì)NO3--N淋失抑制效果最佳，減少了81.52%。初始土壤pH對(duì)DON淋失同樣存在顯著影響（<0.05），初始土壤pH為堿性時(shí)，DON淋失增加了42.95%，而在土壤pH呈酸性時(shí)，DON淋失存在異質(zhì)性。土壤酸堿性是影響土壤溶解性有機(jī)碳和DON含量的重要因素之一[38-39]。前人也通過(guò)整合分析表明[40]：在堿性土壤中，施加有機(jī)肥能顯著提高土壤DON含量。其原因可能是在高pH條件下，土壤微生物活性增強(qiáng)，促進(jìn)土壤有機(jī)物發(fā)生氨化作用，分解形成DON[27]。同時(shí)研究表明：隨著土壤pH升高，鐵鋁氧化物和氫氧化物帶正電荷性降低，對(duì)DON的吸附能力減弱[41]，使得土壤DON更易淋失。

土地利用方式對(duì)TN、NO3--N淋失影響不顯著（=0.56，=0.61）（圖2b），但在旱地中，有機(jī)肥配施化肥使DON淋失顯著增加了26.63%（<0.05），而水田土壤DON淋失具有異質(zhì)性。一方面，旱地主要分布在中國(guó)北方地區(qū)，其積溫低于水田，有利于土壤DON的積累[40]；另一方面，微生物活性在旱地中可能受到抑制，從而減少微生物對(duì)DON的利用[42]，DON淋失風(fēng)險(xiǎn)增大。而水田土壤含水率高，更多的DON可能隨徑流損失[43]。同時(shí)在淹水條件下，厭氧微生物主要通過(guò)反硝化、異養(yǎng)硝化、共反硝化和厭氧氨氧化過(guò)程促進(jìn)N2O、N2排放[44-45]，造成土壤氮素?fù)p失。

2.3 氮淋失系數(shù)的變化

在不同施肥處理下，高有機(jī)肥替代比（70%

注：沒(méi)有收集到pH為6.5～7.5 DON數(shù)據(jù)。DL為旱地，PF為水田。

表2 不同有機(jī)肥替代比下氮淋失系數(shù)

注：SR為有機(jī)肥替代比。

Note: SR is organic fertilizer replacement ratio.

2.4 不確定性及重要性分析

化肥的大量投入使得農(nóng)田氮素通過(guò)淋失、氣體排放等途徑損失，進(jìn)而造成環(huán)境污染。本研究發(fā)現(xiàn)，高替代比的動(dòng)物型有機(jī)肥施入堿性旱地土壤促進(jìn)了DON的淋失（圖 3），但有效抑制了土壤總氮淋失。然而，高替代比動(dòng)物型有機(jī)肥對(duì)于溫室氣體排放的貢獻(xiàn)并不清楚。盡管相關(guān)文獻(xiàn)已經(jīng)報(bào)道高有機(jī)肥替代化肥會(huì)抑制土壤N2O排放，但動(dòng)物型有機(jī)肥抑制效果并不顯著，且種類限于糞便和堆肥[17,46]。而高替代比沼液（高水分，低C/N）對(duì)于土壤N2O排放的影響未知。此外，前人研究表明高有機(jī)肥替代比顯著抑制氮素利用率和蔬菜產(chǎn)量[16]。因此，高有機(jī)肥替代比對(duì)于作物-環(huán)境系統(tǒng)的影響需要后續(xù)試驗(yàn)進(jìn)一步權(quán)衡。

氣候條件、耕作方式及栽培類型等對(duì)土壤氮淋失也存在一定影響。土壤氮素淋溶往往隨降雨、灌溉發(fā)生。研究發(fā)現(xiàn)，在蔬菜系統(tǒng)中，水分輸入與土壤NO3--N淋失呈微弱正相關(guān)[47]。此外，微生物活性在不同環(huán)境溫度下有所差異，升溫可以增加土壤固氮菌和反硝化細(xì)菌豐度[48]，這可能改變硝化反硝化速率進(jìn)而影響土壤氮素淋失。有機(jī)肥施用方式可能會(huì)間接影響土壤氮素淋失。研究發(fā)現(xiàn)，沼液噴施對(duì)土壤NO3--N含量影響較小，但采用沼液注施時(shí)，高替代比的沼液使得表層土壤NO3--N含量顯著提升[49]，進(jìn)而增加了土壤氮素淋失風(fēng)險(xiǎn)；同時(shí)，免耕[50]和模板犁耕[51]能夠有效減少土壤氮素淋失。栽培條件往往影響土壤氮素轉(zhuǎn)化。盡管Liu等[16]研究發(fā)現(xiàn)，對(duì)于蔬菜系統(tǒng)，有機(jī)肥配施化肥均有效抑制露天和溫室土壤TN淋失，但其對(duì)于糧食作物系統(tǒng)和DON淋失的影響具有不確定性。由于數(shù)據(jù)的缺乏，本研究無(wú)法評(píng)估氣溫、耕作方式對(duì)于有機(jī)肥配施化肥下土壤氮素淋失的影響。

注：“？”指未知。

對(duì)施肥行為、土壤pH、土地利用方式等對(duì)TN、NO3--N、DON淋失影響的重要性程度進(jìn)行分析（圖4），結(jié)果表明，有機(jī)肥替代比對(duì)于TN淋失的影響占主導(dǎo)作用，而施氮水平對(duì)NO3--N、DON淋失影響較替代比更為重要。此外，土壤pH也是有機(jī)肥化肥配施下DON淋失的主要影響因素，這可能是因?yàn)閜H升高會(huì)顯著增加土壤有機(jī)質(zhì)的溶解度[52]。因此，在農(nóng)業(yè)生產(chǎn)中應(yīng)針對(duì)性采取不同有機(jī)肥化肥配施模式，有效降低氮素淋失風(fēng)險(xiǎn)。

注：R2為決定系數(shù)。

3 結(jié) 論

本文對(duì)有機(jī)肥化肥配施過(guò)程中，施肥行為（施氮水平、替代比、基追施行為、有機(jī)肥種類）、初始土壤pH、土地利用方式等因素對(duì)氮素淋失的總體影響進(jìn)行整合分析，主要結(jié)論如下：

1）高基施比例與低施氮量（N<200 kg/hm2）能夠顯著抑制氮素淋失，尤其是NO3--N淋失，即少次適量施氮可以有效降低氮淋失風(fēng)險(xiǎn)，但不一定有益于作物產(chǎn)量。

2）高有機(jī)肥替代比（大于70%）能夠有效降低水田與旱地氮素淋失總量，顯著抑制堿性旱地土壤NO3--N淋失，但促進(jìn)了溶解性有機(jī)氮（Dissolved Organic Nitrogen，DON）淋失，其中，動(dòng)物型有機(jī)肥的施用對(duì)DON淋失促進(jìn)效果更為顯著。

3）有機(jī)肥化肥配施過(guò)程中，減少氮淋失應(yīng)優(yōu)先控制有機(jī)肥替代比、施氮水平。

[1] 周偉，呂騰飛，楊志平，等. 氮肥種類及運(yùn)籌技術(shù)調(diào)控土壤氮素?fù)p失的研究進(jìn)展[J]. 應(yīng)用生態(tài)學(xué)報(bào)，2016，27(9)：3051-3058.

Zhou Wei, Lyu Tengfei, Yang Zhiping, et al. Research advances on regulating soil nitrogen loss by the type of nitrogen fertilizer and its application strategy[J]. Chinese Journal of Applied Ecology, 2016, 27(9): 3051-3058. (in Chinese with English abstract)

[2] Liu J G, You L Z, Amini M, et al. A high-resolution assessment on global nitrogen flows in cropland[J]. Proceedings of the National Academy of Sciences of the United States of America, 2010, 107(17): 8035-8040.

[3] 史鑫蕊，徐強(qiáng)，胡克林，等. 灌水次數(shù)對(duì)綠洲春玉米田氮素?fù)p失及水氮利用效率的影響[J]. 農(nóng)業(yè)工程學(xué)報(bào)，2018，34(3)：118-126.

Shi Xinrui, Xu Qiang, Hu Kelin, et al. Effect of irrigation times on nitrogen loss, water and nitrogen use efficiencies in oasis spring maize farmland[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2018, 34(3): 118-126. (in Chinese with English abstract)

[4] 朱兆良. 農(nóng)田中氮肥的損失與對(duì)策[J]. 生態(tài)環(huán)境學(xué)報(bào)，2000，9(1)：1-6.

Zhu Zhaoliang. Loss of fertilizer N from plants-soil system and the strategies and techniques for its reduction[J]. Ecology and Environmental Sciences, 2000, 9(1): 1-6. (in Chinese with English abstract)

[5] Guo S F, Pan J T, Zhai L M, et al. The reactive nitrogen loss and GHG emissions from a maize system after a long-term livestock manure incorporation in the North China Plain[J]. The Science of the Total Environment, 2020, 720: 137558.

[6] Liang H, Lv H, Batchelor W D, et al. Simulating nitrate and DON leaching to optimize water and N management practices for greenhouse vegetable production systems[J]. Agricultural Water Management, 2020, 241: 106377.

[7] Zheng W, Wang S, Liu B, et al. Simulation of the migration and leaching of nitrate nitrogen in the farmland soil profile in a hilly area of Taihang Mountain with the RZWQM model[J]. Environmental Science, 2019, 40(4): 1770-1778.

[8] 商放澤，楊培嶺，李云開(kāi)，等. 不同施氮水平對(duì)深層包氣帶土壤氮素淋溶累積的影響[J]. 農(nóng)業(yè)工程學(xué)報(bào)，2012，28(7)：103-110.

Shang Fangze, Yang Peiling, Li Yunkai, et al. Effects of different chemical nitrogenous fertilizer application rates on soil nitrogen leaching and accumulation in deep vadose zone[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2012, 28(7): 103-110. (in Chinese with English abstract)

[9] 徐大兵，趙書軍，袁家富，等. 有機(jī)肥替代氮化肥對(duì)葉菜產(chǎn)量品質(zhì)和土壤氮淋失的影響[J]. 農(nóng)業(yè)工程學(xué)報(bào)，2018，34(增刊)：13-18.

Xu Dabing, Zhao Shujun, Yuan Jiafu, et al. Chemical N fertilizer replaced with organic fertilizer affecting yield and quality of leaf vegetable and N leaching in soils[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2018, 34(Supp.): 13-18. (in Chinese with English abstract)

[10] 韓佳樂(lè)，馮濤，朱志軍，等. 生長(zhǎng)模型和15N示蹤評(píng)價(jià)施肥處理對(duì)蘋果樹(shù)氮肥利用的影響[J]. 農(nóng)業(yè)工程學(xué)報(bào)，2021，37(15)：96-104.

Han Jiale, Feng Tao, Zhu Zhijun, et al. Evaluating the effects of fertilization treatments on the nitrogen use efficiency of apple trees using allometric model and15N tracer[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2021, 37(15): 96-104. (in Chinese with English abstract)

[11] 李勝君，胡菏，李剛，等. 化肥減量與有機(jī)物料添加對(duì)華北潮土微生物氮循環(huán)功能基因豐度和氮轉(zhuǎn)化遺傳潛力的影響[J]. 環(huán)境科學(xué)，2022，43(10)：4735-4744.

Li Shengjun, Hu He, Li Gang, et al. Impacts of co-application of chemical fertilizer reduction and organic material amendment on fluvo-aquic soil microbial N-cycling functional gene abundances and N-converting genetic potentials in northern China[J]. Environmental Science, 2022, 43(10): 4735-4744. (in Chinese with English abstract)

[12] Wan L J, Tian Y, He M, et al. Effects of chemical fertilizer combined with organic fertilizer application on soil properties, citrus growth physiology, and yield[J]. Agriculture, 2021, 11(12): 1207.

[13] 胡冬妮，董志新，朱波. 有機(jī)肥替代化肥對(duì)紫色土坡耕地氮素流失的影響[J]. 中國(guó)生態(tài)農(nóng)業(yè)學(xué)報(bào)(中英文)，2022，30(3)：431-440.

Hu Dongni, Dong Zhixin, Zhu Bo. Impact of substitution of synthetic N fertilizer with organic fertilizers on nitrogen loss from sloping cropland of purple soil[J]. Chinese Journal of Eco-Agriculture, 2022, 30(3): 431-440. (in Chinese with English abstract)

[14] Tang Q, Cotton A, Wei Z, et al. How does partial substitution of chemical fertiliser with organic forms increase sustainability of agricultural production?[J]. Science of The Total Environment, 2022, 803: 149933.

[15] Song X, Zhang J, Peng C, et al. Replacing nitrogen fertilizer with nitrogen-fixing cyanobacteria reduced nitrogen leaching in red soil paddy fields[J]. Agriculture Ecosystems & Environment, 2021, 312: 107320.

[16] Liu B, Wang X, Ma L, et al. Combined applications of organic and synthetic nitrogen fertilizers for improving crop yield and reducing reactive nitrogen losses from China's vegetable systems: A meta-analysis[J]. Environmental Pollution, 2021, 269: 116143.

[17] Xia L, Shu K L, Yan X. et al. How does recycling of livestock manure in agroecosystems affect crop productivity, reactive nitrogen losses, and soil carbon balance?[J]. Environmental Science & Technology, 2017, 51(13): 7450-7457.

[18] Nasholm T, Ekblad A, Nordin A, et al. Boreal forest plants take up organic nitrogen[J]. Nature, 1998, 392(6679): 914-916.

[19] Barton L, Wan G G Y, Colmer T D. Turfgrass (L. ) sod production on sandy soils II: Effects of irrigation and fertiliser regimes on N leaching[J]. Plant And Soil, 2006, 284(1/2): 147-164.

[20] Kessel C V, Clough T, Groenigen J, et al. Dissolved organic nitrogen: an overlooked pathway of nitrogen loss from agricultural systems?[J]. Journal of Environmental Quality, 2009, 38(2): 393-401.

[21] Huang M X, Tao L, Zhu O Y, et al. Leaching losses of nitrate nitrogen and dissolved organic nitrogen from a yearly two crops system, wheat-maize, under monsoon situations[J]. Nutrient Cycling in Agroecosystems, 2011, 91(1): 77-89.

[22] Skinner C, Gattinger A, Muller A, et al. Greenhouse gas fluxes from agricultural soils under organic and non-organic management-A global meta-analysis[J]. Science of the Total Environment, 2014, 468/469: 553-563.

[23] Cao Y B, Wang X, Bai Z, et al. Mitigation of ammonia, nitrous oxide and methane emissions during solid waste composting with different additives: A meta-analysis[J]. Journal of Cleaner Production, 2019, 235: 626-635.

[24] Hedges L V, Gurevitch J, Curtis P. The meta-analysis of response ratios in experimental ecology[J]. Ecology, 1999, 80(4): 1150-1156.

[25] 葉靜，安藤豐，符建榮，等. 不同有機(jī)肥對(duì)土壤中的氮素礦化及對(duì)化肥氮固持的影響[J]. 浙江農(nóng)業(yè)學(xué)報(bào)，2008，20(3)：176-180.

Ye Jing, Ho Ando, Fu Jianrong, et al. Effects of different organic manures on N mineralization and N retention in the soil[J]. Acta Agriculturae Zhejiangensis, 2008, 20(3): 176-180. (in Chinese with English abstract)

[26] Fan J, Xiao J, Liu D, et al. Effect of application of dairy manure, effluent and inorganic fertilizer on nitrogen leaching in clayey fluvo-aquic soil: A lysimeter study[J]. Science of the Total Environment, 2017, 592: 206-214.

[27] 全智，劉軒昂，劉東. 土壤可溶性有機(jī)氮研究進(jìn)展[J]. 應(yīng)用生態(tài)學(xué)報(bào)，2022，33(1)：277-288.

Quan Zhi, Liu Xuanang, Liu Dong. Research progress on soil soluble organic nitrogen[J]. Chinese Journal of Applied Ecology, 2022, 33(1): 277-288. (in Chinese with English abstract)

[28] Wei Z, Hoffland E, Zhuang M, et al. Organic inputs to reduce nitrogen export via leaching and runoff: A global meta-analysis[J]. Environmental Pollution, 2021, 291: 118176.

[29] 榮勤雷，李若楠，黃紹文，等. 不同施肥模式下設(shè)施菜田土壤團(tuán)聚體養(yǎng)分和微生物量特征[J]. 植物營(yíng)養(yǎng)與肥料學(xué)報(bào)，2019，25(7)：1084-1096.

Rong Qinlei, Li Ruonan, Huang Shaowen, et al. Characteristics of nutrients and microbial biomass in soil aggregates under different fertilization modes in greenhouse vegetable production[J]. Journal of Plant Nutrition and Fertilizers, 2019, 25(7): 1084-1096. (in Chinese with English abstract)

[30] 安祥瑞，江尚燾，謝昶琰，等. 減施化肥配施有機(jī)肥對(duì)荔枝園土壤微生物區(qū)系的影響[J]. 應(yīng)用生態(tài)學(xué)報(bào)，2022，33(4)：1099-1108.

An Xiangrui, Jiang Shangtao, Xie Changyan, et al. Effects of reducing chemical fertilizers combined with organic fertilizers on soil microbial flora in litchi orchards[J]. Chinese Journal of Applied Ecology, 2022, 33(4): 1099-1108. (in Chinese with English abstract)

[31] 周斌，喬木，王周瓊. 長(zhǎng)期定位施肥對(duì)灰漠土農(nóng)田土壤質(zhì)量的影響[J]. 中國(guó)生態(tài)農(nóng)業(yè)學(xué)報(bào)，2007，15(2)：33-36.

Zhou Bin, Qiao Mu, Wang Zhouqiong. Effects of a long-term located fertilization on soil quality of grey desert soil[J]. Chinese Journal of Eco-Agriculture, 2007, 15(2): 33-36. (in Chinese with English abstract)

[32] 趙玉皓，張艷杰，李貴春，等. 長(zhǎng)期不同施肥下褐土有機(jī)碳儲(chǔ)量及活性碳組分[J]. 生態(tài)學(xué)雜志，2016，35(7)：1826-1833.

Zhao Yuhao, Zhang Yanjie, Li Guichun, et al. Soil organic carbon stock and active carbon fractions under four kinds of long-term fertilization[J]. Chinese Journal of Ecology, 2016, 35(7): 1826-1833. (in Chinese with English abstract)

[33] Murphy D V, Macdonald A J, Stockdale E A, et al. Soluble organic nitrogen in agricultural soils[J]. Biology & Fertility of Soils, 2000, 30(5/6): 374-387.

[34] Bhogal A, Williams J R, Nicholson F A, et al. Mineralization of organic nitrogen from farm manure applications[J]. Soil Use & Management, 2016, 32: 32-43.

[35] 田飛飛，紀(jì)鴻飛，王樂(lè)云，等. 施肥類型和水熱變化對(duì)農(nóng)田土壤氮素礦化及可溶性有機(jī)氮?jiǎng)討B(tài)變化的影響[J]. 環(huán)境科學(xué)，2018，39(10)：4717-4726.

Tian Feifei, Ji Hongfei, Wang Leyun, et al. Effects of various combinations of fertilizer, soil moisture, and temperature on nitrogen mineralization and soluble organic nitrogen in agricultural soil[J]. Environmental Science, 2018, 39(10): 4717-4726. (in Chinese with English abstract)

[36] Wang J, Zhu B, Zhang J B, et al. Mechanisms of soil N dynamics following long-term application of organic fertilizers to subtropical rain-fed purple soil in China[J]. Soil Biology & Biochemistry, 2015, 91: 222-231.

[37] Zeng W, Qiu J, Wang D, et al. Ultrafiltration concentrated biogas slurry can reduce the organic pollution of groundwater in fertigation[J]. Science of the Total Environment, 2021, 810: 151294.

[38] 田靜，郭景恒，陳海清，等. 土地利用方式對(duì)土壤溶解性有機(jī)碳組成的影響[J]. 土壤學(xué)報(bào)，2011，48(2)：338-346.

Tian Jing, Guo Jingheng, Chen Haiqing, et al. Effect of land use on composition of soil dissolved organic carbon[J]. Acta Pedologica Sinica, 2011, 48(2): 338-346. (in Chinese with English abstract)

[39] Anderson C, Peterson M, Curtin D. Base cations, K+and Ca2+, have contrasting effects on soil carbon, nitrogen and denitrification dynamics as pH rises[J]. Soil Biology and Biochemistry, 2017, 113: 99-107.

[40] 李亞林，張旭博，任鳳玲，等. 長(zhǎng)期施肥對(duì)中國(guó)農(nóng)田土壤溶解性有機(jī)碳氮含量影響的整合分析[J]. 中國(guó)農(nóng)業(yè)科學(xué)，2020，53(6)：1224-1233.

Li Yalin, Zhang Xubo, Ren Fengling, et al. A meta-analysis of long-term fertilization impact on soil dissolved organic carbon and nitrogen across Chinese cropland[J]. Scientia Agricultura Sinica, 2020, 53(6): 1224-1233. (in Chinese with English abstract)

[41] Kaiser K, Guggenberger G, Haumaier L, et al. Dissolved organic matter sorption on subsoils and minerals studied by 13C-NMR and DRIFT spectroscopy[J]. European Journal of Soil Science, 2010, 48(2): 301-310.

[42] Lundguist E J, Jackson L E, Scow K M, et al. Changes in microbial biomass and community composition, and soil carbon and nitrogen pools after incorporation of rye into three California agricultural soils[J]. Soil Biology & Biochemistry, 1999, 31(2): 221-236.

[43] Nie S, Zhao L, Lei X, et al. Dissolved organic nitrogen distribution in differently fertilized paddy soil profiles: Implications for its potential loss[J]. Agriculture, Ecosystems & Environment, 2018, 262: 58-64.

[44] 李靳，康榮華，于浩明，等. 土壤水分對(duì)土壤產(chǎn)生氣態(tài)氮的厭氧微生物過(guò)程的影響[J]. 應(yīng)用生態(tài)學(xué)報(bào)，2021，32(6)：1989-1997.

Li Jin, Kang Ronghua, Yu Haoming, et al. Effects of soil moisture on microbial processes of soil nitrogen gases production under anaerobic conditions[J]. Chinese Journal of Applied Ecology, 2021, 32(6): 1989-1997. (in Chinese with English abstract)

[45] Liu H, Ding Y, Zhang Q, et al. Heterotrophic nitrification and denitrification are the main sources of nitrous oxide in two paddy soils[J]. Plant and Soil, 2018, 445(1/2): 39-53.

[46] Zhou M, Zhu B, Wang S, et al. Stimulation of N2O emission by manure application to agricultural soils may largely offset carbon benefits: A global meta-analysis[J]. Global Change Biology, 2017, 23(10): 4068-4083.

[47] Wang X Z, Zou C Q, Gao X P, et al. Nitrate leaching from open-field and greenhouse vegetable systems in China: A meta-analysis[J]. Environmental Science and Pollution Research, 2018, 25(31): 31007-31016.

[48] 馬秀艷，蔣磊，宋艷宇，等. 溫度和水分變化對(duì)凍土區(qū)泥炭地土壤氮循環(huán)功能基因豐度的影響[J]. 生態(tài)學(xué)報(bào)，2021，41(17)：6707-6717.

Ma Xiuyan, Jinag Lei, Song Yanyu, et al. Effects of temperature and moisture changes on functional gene abundance of soil nitrogen cycle in permafrost peatland[J]. Acta Ecologica Sinica, 2021, 41(17): 6707-6717. (in Chinese with English abstract)

[49] 劉聰，鄭瑤琪，劉爽，等. 秋閑期沼液施用對(duì)黑土區(qū)土壤氮素?fù)p失的影響[J]. 農(nóng)業(yè)環(huán)境科學(xué)學(xué)報(bào)，2021，40(11)：2528-2536.

Liu Cong, Zheng Yaoqi, Liu Shuang, et al. Effects of biogas slurry application on nitrogen loss soil in black soil area during the autumn fallow period[J]. Journal of Agro-Environment Science, 2021, 40(11): 2528-2536. (in Chinese with English abstract)

[50] Zhang Y, Xie D, Ni J, et al. Conservation tillage practices reduce nitrogen losses in the sloping upland of the Three Gorges Reservoir area: No-till is better than mulch-till[J]. Agriculture Ecosystems & Environment, 2020, 300: 107003.

[51] 王維剛，史海濱，李仙岳，等. SWAT模擬耕作方式與鹽分對(duì)區(qū)域土壤氮運(yùn)移及作物產(chǎn)量影響[J]. 農(nóng)業(yè)工程學(xué)報(bào)，2022，38(3)：55-65.

Wang Weigang, Shi Haibin, Li Xianyue, et al. Effects of tillage modes and soil salinity on regional nitrate nitrogen transport and crop yields using a SWAT model[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2022, 38(3): 55-65. (in Chinese with English abstract)

[52] Cookson W R, osman M, Marschner P, et al. Controls on soil nitrogen cycling and microbial community composition across land use and incubation temperature[J]. Soil Biology & Biochemistry, 2007, 39(3): 744-756.

Meta-analysis of the effects of combined application of organic and chemical fertilizers on soil nitrogen leaching

Teng Ying1,2, Kong Fanjing1,2, Chen Yucheng1,2, Chen Siyang1,2, Xiong Hailing3, Zhu Kangwen4, Yang Zhimin1,2※

(1.,,400716,; 2.,,400716,; 3.,,400715; 4.-,401147,)

Nitrogen is one of the most essential elements for crop growth. Nitrogen fertilizer has been widely applied to increase crop yields. At the same time, a large number of negative impacts have posed a great threat to the ecological environment in recent years. Among them, nitrogen leaching can be attributed to the excessive application of chemical fertilizers in farmland. Fortunately, the combined application of organic and chemical fertilizers can be expected to effectively reduce soil nitrogen leaching in normal fertilization during agricultural production at present. Therefore, this study aims to explore the combination application mode of organic and chemical fertilizers with a low risk of nitrogen leaching in farmland. The search terms were selected as chemical fertilizer, organic fertilizer, and nitrogen leaching using the two databases of China National Knowledge Infrastructure (CNKI) and Web of Science. The peer-reviewed and published papers were then obtained up to January 2022. Finally, a total of 35 papers (22 papers from Web of Science, 13 papers from CNKI) and 331 effective data pairs were collected after screening for the combination application of organic and chemical fertilizers in farmland. The target variables were taken as the total nitrogen (TN), nitrate nitrogen (NO3--N), and dissolved organic nitrogen (DON), while the chemical fertilizer was the control. After that, Metawin 2.1 software was used to determine the overall effects of the total amount of fertilization, fertilization structure (organic fertilizer substitution ratio), fertilization time (basic topdressing), and the types of organic fertilizers on the nitrogen leaching, where the chemical fertilizer was as the control. The results showed that there was a significant influence of the above fertilization behavior on nitrogen leaching. Once the total amount of nitrogen was less than 200 kg/hm2, the leaching of TN and NO3--N in farmland decreased by 36.77% and 65.05%, respectively. When the substitution ratio of organic fertilizers was higher than 70%, the TN leaching was reduced by 39.64%, whereas the risk of dissolved DON leaching increased by 15.78%. Especially, there was a 26.31% increase in DON leaching in the application of animal-based organic fertilizers combined with chemical fertilizers. Correspondingly, the application of nitrogen fertilizer significantly reduced the leaching of TN and NO3--N by 43.58% and 70.51%(<0.05), respectively. A certain impact was also found in the soil pH and land use patterns on nitrogen leaching. For example, the combined application of organic and chemical fertilizers on the alkaline dryland soil effectively inhibited the leaching of TN and NO3--N, whereas, there was an increase in the leaching of DON by 26.63%-42.95%. Nitrogen leaching in dryland was dominated by the NO3--N leaching. By contrast, the emission factor (EF) was higher than that in the paddy field. The increasing replacement ratio of organic fertilizers can be expected to greatly reduce the soil nitrogen leaching in dryland, but to enhance the DON leaching. In addition, the Matlab software was used to analyze the importance of factors using the random forest model. Specifically, the replacement ratio of organic fertilizer demonstrated a dominant effect on TN leaching. There was also the more important effect of the nitrogen application level on the NO3--N and DON leaching. Therefore, the low level of nitrogen application and the high substitution ratio of animal-based organic fertilizers can be used to effectively reduce the soil nitrogen leaching loss in the alkaline dryland, compared with the chemical fertilizers only. The finding can provide the practical basis for the combined application of organic and chemical fertilizers in farmland.

fertilizers; nitrogen; leaching; organic fertilizer; DON

10.11975/j.issn.1002-6819.2022.22.009

S146；S157

A

1002-6819(2022)-22-0081-08

滕穎，孔凡靖，陳玉成，等. 有機(jī)無(wú)機(jī)肥配施模式對(duì)氮素淋失的影響[J]. 農(nóng)業(yè)工程學(xué)報(bào)，2022，38(22)：81-88.doi：10.11975/j.issn.1002-6819.2022.22.009 http://www.tcsae.org

Teng Ying, Kong Fanjing, Chen Yucheng, et al. Meta-analysis of the effects of combined application of organic and chemical fertilizers on soil nitrogen leaching[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2022, 38(22): 81-88. (in Chinese with English abstract) doi：10.11975/j.issn.1002-6819.2022.22.009 http://www.tcsae.org

2022-05-10

2022-09-10

重慶市技術(shù)創(chuàng)新與應(yīng)用發(fā)展示范專項(xiàng)重點(diǎn)研發(fā)項(xiàng)目（cstc2019jscx-gksbX0103）；重慶榮昌農(nóng)牧高新技術(shù)產(chǎn)業(yè)研發(fā)專項(xiàng)（cstc2020ngzx0010）；重慶市自然科學(xué)基金面上項(xiàng)目（CSTB2022NSCQ-MSX0538）

滕穎，研究方向?yàn)檗r(nóng)業(yè)面源污染控制。Email：1351594843@qq.com

楊志敏，副教授，研究方向?yàn)檗r(nóng)業(yè)面源污染控制。Email：bear@swu.edu.cn