甜菜对土壤肥力及酶活性影响的初步分析

研究结果表明，在被测定的１２种甜菜土壤养分含量中，有１０种养分含量低于对照（麦地）．其中，碱解氮，有效镁和有效锰的差异较大，其差值分别为２６ｐｐｍ、１１．５ｐｐｍ和７．４ｐｐｍ，其余差异不大；在甜菜营养生长期内，分别测定了甜菜与对照土壤的微生物总量、细菌、放线菌和真菌的数量及消长动态；土壤碱解氮含量和耕层地温对细菌数量有一定的影响；甜菜土壤的３项酶活性均低于同期的对照。在甜菜吸收氮素的高峰期，土壤中脲酶活性亦明显增强，达到１．２２ＮＨ＿３－Ｎｍｇ／ｇ土。在幼苗期至糖分积累期，磷酸酶活性与甜菜苗龄呈正相关关系（ｒ＝０．９２２３￣＊）。

A Pre liminary Analysis on Soil Fertility and Effect of Enzyme Activity

The research results have shown that the content of 12 kinds of soil nutrients,there were10 kinds of nutrients content lower than check (mheat fields),among them,the alkalinehydrolysis N,available magnesium and Mn have significant difference which were 26ppm,11.5ppm and 7.4ppm,and others were no significant difference,we determined the amount ofsoil organism,bacterium,actinomyces and fungus of check and the dynamic of its eliminateand growth,there were certain effect of content of soil alkaline hydrolysis N and temperatureof plowing layer to the amount of bacterium,three enzyme activities of sugarbeet soil werelower than check in the growing season,The activity of urease was higher in the soil,itreached 1.22NH_3 N mg/g soil during high peak peroid of N uptaking,activity ofphosphatase have a positive coorelation with seedling ages from the seedling stage to sugaraccumulation stage.