黄河口碱蓬湿地土壤磷矿化特征对氮负荷及水分的响应  

Effects of nitrogen loading and soil moisture on phosphorus mineralization characteristics in soils of Suaeda salsa marsh in the Yellow River estuary

作　　者：孙志高[1,2,3] 俞琳莺 陈冰冰[1,3] 胡星云 武慧慧[1,3] SUN Zhigao;YU Linying;CHEN Bingbing;HU Xingyun;WU Huihui(Fujian Provincial Key Laboratory for Subtropical Resources and Environment,Fujian Normal University,Fuzhou 350007;Key Laboratory of Humid Subtropical Eco-geographical Process(Fujian Normal University),Ministry of Education,Fuzhou 350007;Institute of Geography,Fujian Normal University,Fuzhou 350007)

机构地区：[1]福建师范大学福建省亚热带资源与环境重点实验室,福州350007 [2]福建师范大学湿润亚热带生态地理过程教育部重点实验室,福州350007 [3]福建师范大学地理研究所,福州350007

出　　处：《环境科学学报》2023年第4期457-466,共10页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金面上项目(No.41371104,41971128);福建省“闽江学者奖励计划”项目。

摘　　要：选择黄河口北部滨岸高潮滩的碱蓬湿地为研究对象,基于野外原位氮负荷增强模拟试验(NL0,对照处理;NL1,低氮负荷处理;NL2,中氮负荷处理;NL3,高氮负荷处理),于生长季末获取相应氮负荷水平下的表层土壤(分别记为NLS0、NLS1、NLS2和NLS3),通过室内开放培养系统,在25℃的淹水和非淹水条件下,探讨了湿地土壤磷矿化特征对氮负荷及水分的响应.结果表明,不同水分条件下各氮负荷处理土壤的磷矿化量均以初期最高(0~28 d),之后迅速降低(28~88 d),并于后期趋于平稳(88~118 d).不同水分条件下的土壤磷矿化特征可能主要与培养过程中相应氮负荷水平下的pH有关.连续培养118 d后,NLS0、NLS1、NLS2和NLS3的磷累积矿化量在非淹水条件下分别为6.62、6.78、8.15和7.15 mg·kg^(-1),在淹水条件下分别为5.88、6.15、6.01和5.71 mg·kg^(-1),非淹水条件下的土壤具有更高的磷矿化能力.不同氮负荷处理土壤的磷矿化量主要来自培养的前28 d,其累积矿化量占总矿化量的比例在非淹水和淹水条件下分别达76.93%~82.63%和78.21%~84.18%.不同氮负荷处理土壤的磷矿化潜势(P0)在非淹水条件下表现为NLS2>NLS3>NLS1>NLS0,而在淹水条件下表现为NLS1>NLS2>NLS0>NLS3.研究发现,尽管氮负荷增强并未显著改变土壤磷矿化特征,但其整体上提高了土壤磷矿化能力和供磷潜势,中氮负荷处理下的土壤供磷能力最高且较为稳定,而高氮负荷处理下的土壤供磷能力最不稳定.The topsoil influenced by different nitrogen(N)loading levels(NLS0,NLS1,NLS2 and NLS3)were sampled at the end of the growing season from the corresponding N loading enhancement plots(NL0,no N loading treatment;NL1,low N loading treatment;NL2,middle N loading treatment;and NL3,high N loading treatment)in Suaeda salsa marsh in high tidal flat of the northern Yellow River estuary.The effects of N loading and soil moisture on phosphorus(P)mineralization characteristics in the four soils were explored by means of an open-incubation system at 25℃under un-flooded and flooded conditions.Results showed that,under distinct soil moisture conditions,the mineralized P of soils in different N loading treatments were the highest at initial stage(0~28 d),after which declined suddenly at middle stage(28~88 d),and then tended toward stability at final stage(88~118 d).In different soil moisture conditions,the variations of mineralized P in soils in distinct N loading levels might be dependent on the variations of pH during incubation.During 118 d incubation,the cumulative amounts of mineralized P in NLS0、NLS1、NLS2 and NLS3 were 6.62,6.78,8.15 and 7.15 mg·kg^(-1) at un-flooded condition and 5.88,6.15,6.01 and 5.71 mg·kg^(-1) at flooded condition,indicating that higher potential of mineralized P generally occurred at un-flooded condition.The cumulative amounts of mineralized P in soils in different N loading treatments mainly rested with the mineralization contributions of initial stage(0~28 d)and the values at un-flooded and flooded conditions were 76.93%~82.63%and 78.21%~84.18%,respectively.The potentially mineralizable P pool(P0)in soils in different N loading treatments at un-flooded condition showed NLS2>NLS3>NLS1>NLS0,while those at flooded condition showed NLS1>NLS2>NLS0>NLS3.This paper found that although N loading enhancement did not alter the characteristics of P mineralization significantly, it generally elevated the potential of mineralized P. It should be noted that the soils inmiddle N loading treatments showed

关 键 词：磷矿化 氮负荷 湿地土壤 碱蓬湿地 黄河口 

分 类 号：X171.1[环境科学与工程—环境科学]