EUF析滤出的矿质氮源及其反映土壤供氮能力方面的效果  

The Sources of Mineral N Released by EUF and Their Effect on Reflection of Soil Nitrogen Supplying Capacity

作　　者：李生秀[1] 李和生[1] 

机构地区：[1]西北农业大学农化系,陕西杨陵712100

出　　处：《西北农林科技大学学报（自然科学版）》1992年第S1期32-39,共8页Journal of Northwest A&F University(Natural Science Edition)

基　　金：陕西省科委资助项目

摘　　要：分别用EUF,KCl和水析滤浸取了肥力不同的12种土壤中的氮素,并研究了不同方法浸出的氮素与黑麦草吸氮量的关系。研究表明,EUF法析滤出来的NO_3^--N与KCl和水浸出的大致接近,并没有使土壤中易矿化的有机氮氧化成NO_3^--N而浸出;析滤出来的NH_4^+-N仍是土壤中的可代换铵,既没有担负固定铵释放的信息,也没有提供易矿化有机N分解的信息。不同方法浸取的NO_3^--N都与黑麦草吸氮量有密切关系,而获得的NH_4^+-N情况相反。用KCl浸取的NO_3^--N与黑麦草吸氮量的关系比EUF析滤出来的NO_3^--N更为密切,而浸取方法的简单方便又为EUF所不及。EUF, KC1 and water were used to release and extract mineral N from 12 soils with different fertilities, and the correlations between N extracted by different methods and N uptake by raygrass in 3 cuts ware studied.The results obtained show that the. nitrate N released by EUF was similar in amounts to those extracted by KC1 or water, indicating that the EUF was unable to oxidize the readily mineralizable N into NOj-N and then released. The results also show that the NH4+-N released by EUF was still the soil exchangeable ammonium, giving neither information on N release from reserves nor information on the release from fixed ammonium. The NO3--N extracted by any method was closely correlated with plant uptake N, but the reverse was true for the extracted NH4+-N. The NO3--N extracted by KC1 was more correlated with N uptake by plants than that released by EUF, and the KC1 method is superior in its simple and convenient extraction of NO3--N to the EUF.

关 键 词：电超滤法(EUF) EUF-N NH₄⁺-N NO₃^--N 

分 类 号：S[农业科学]