[目的]研究闽江河口土壤氮矿化速率对干土的响应.[方法]选取闽江河口鳝鱼滩高潮滩秋茄[Kandelia candel(Linn.) Druce)]芦苇(Phragmites australis)、互花米草(Spartina alterniflora)和成草(Cyperus malaccensis)4种不同植被覆被的沼泽湿地采样,以这4种不同土壤的鲜土样与风干土样为供试材料进行室内培养试验,分析pH、水含量和NH4+-N、NO2--N、NO3--N含量,研究干土效应对土壤氮矿化作用的影响.[结果]鲜土无明显的硝化作用,氨化作用是其主要的氮矿化来源.鲜土矿化速率表现为互花米草[2.63±0.48 μg/(g· h)]＞芦苇[2.39±0.05 μg/(g·h)]＞成草[2.20±0.47 μg/(g·h)]＞秋茄[1.94±0.29 μg/(g·h)].而风干土复水试验结果表明,秋茄和成草风干土的最佳复水时间均为4d,而互花米草和芦苇则为4～7d.[结论]该研究可为氮循环研究提供参考.%[Objective]The aim is to study the responses of soil nitrogen mineralization characteristics to dry soil effect in Min River estuary.[Method] With incubation test,responses of soil nitrogen mineralization characteristics in Min River estuary to dry soil effect were studied.The soil samples included dried soil and wet soil,which were collected from the brackish marsh of Kandelia candel (Linn.) Druce,Phragmites australis,Spartina alterniflora,and Cyperus malaccensis in Shanyutan wetland.Various soil properties were measured including the pH,moisture,and the contents of NH4 +-N,NO2--N,and NO3--N.[Result] Wet soil mineralization rate was WH [2.63 ± 0.48 μg/(g · h)] ＞ WL [2.39 ± 0.05 μg/(g· h)] ＞ WX [2.20 ± 0.47 μg/ (g· h)] ＞ WQ [1.94 ± 0.29 μg/(g· h)].The fresh soil nitrification was no obvious,and the ammonification was the main source of nitrogen mineralization.Dry soil effect experiments showed that 4 days was the best time of incubation for sediments covered by Kandelia candel (Linn.) Druce and Cyperus malaccensis,while 4 to 7 days for Phragmites australis and Spartina alterniflora.[Conclusion] The research can provide reference for studying nitrogen cycle.
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