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用黑麦草进行两个主要目标的盆栽试验：（１）观察可浸提的有机氮对纯矿化氮和植物吸收氮的重要性；（２）研究施入土壤中有机质的分解和矿化与可浸提有机氮的关系。可浸提的有机氮采用电超滤法（ＥＵＦ）和１０ｍＭＣａＣｌ２溶液浸提。试验采用德国汉森冲积物和斑状沉淀物发育而成的１３种砂土，试验土样采自生长黑麦的田间试验小区表层，取样时间为６月份。 ＣａＣｌ２浸提有机氮与净矿化氮和黑麦吸收氮有明显关系（相关系数ｒ２＝０．６０和ｒ２＝０．６６，而与用电超滤法（ＥＵＦ）浸提的有机氮关系不很明显（ｒ２＝０．１６和 ０．２２）；测定与土壤全氮的相关系数分别为ｒ２＝０． ２３和 ０．３３。 施入土壤的甜菜叶子的分解和矿化增加了植物可吸收的有效Ｎ，这就明显表明增加了土壤的无机Ｎ和可浸提的有机态Ｎ，随后有机态Ｎ和无机态Ｎ的减少与黑麦吸收Ｎ有关。然而不同时间可浸提的有机态Ｎ含量决定于采用的浸提方法，加入有机物两ｗｅｅｋ后取样电超滤（ＥＵＦ）法可没提的有机态Ｎ最高。相反，当加入有机物４ｗｅｅｋ时取样用ＣａＣｌ２浸提法没提的有机态Ｎ量达到最高。虽然在开始时不同土样浸提出的有机态Ｎ相差较大，但加入有机物后的净矿化量几乎没有差异，这反映出了土壤微生物活性
Ryegrass was used to conduct two main objectives of the pot experiment: (1) to observe the importance of extractable organic N for NPN and N uptake by plants; (2) to study the decomposition and mineralization of organic matter applied to the soil Organic nitrogen extraction can be the relationship. Leachable organic nitrogen was extracted by electrofiltration (EUF) and 10 mM CaCl2. Thirteen kinds of sand developed from the German Hansen alluvium and the porphyritic sediment were used in the experiment. The soil samples were collected from the surface of field test plots of growing rye and the sampling time was June. The organic nitrogen extracted by CaCl2 has a clear relationship with N2O and nitrogen uptake of rye (r2 = 0.60 and r2 = 0.66, but not with organic nitrogen extracted by electrofiltration) (R2 = 0.16 and 0.22). The correlation coefficient between soil total nitrogen and determination was r2 = 0. 23 and 0.33, respectively. The decomposition and mineralization of beet leaves applied to the soil increased the plant absorbability Of the available N, which clearly indicates that soil inorganic N and extractable organic N are increased, followed by the reduction of organic N and inorganic N relative to the N uptake by N. However, the organic N extractable at different times The content is determined by the leaching method, and the highest content of organic N which could not be extracted by EUF method after adding organics for two weeks is the highest.On the contrary, when the organic matter 4week is sampled, the organic N Although the difference between the organic N extracted by different soil samples was large at the beginning, there was almost no difference in the amount of net mineralization after adding organic matter Reflect the soil microbial activity