黄土高原旱地轮作与施肥长期定位试验研究 Ⅱ.土壤酶活性与土壤肥力

本文分析了长期试验土壤酶活性与土壤有机C、全N、有效P含量、主要微生物类群之间的关系。相关分析表明,土壤脲酶、碱性磷酸酶、蛋白酶活性随土壤有机C含量的增加而增加,蔗糖酶、过氧化氢酶活性与有机C之间的关系因施肥种类及种植方式的不同而不同;微生物数量仅真菌与脲酶、蛋白酶活性之间的相关性达到显著水平。除过氧化氢酶外,其它4种酶的活性均与当年种植冬小麦处理的产量存在显著相关关系。利用主成分分析与通径分析揭示了土壤酶活性与养分之间的内在关系及酶活性对土壤养分的影响。根据主成分分析结果,旱地土壤肥力状况用脲酶、碱性磷酸酶、蛋白酶活性作为综合评价指标优于过氧化氢酶与蔗糖酶。

Study on long-term experiment of crop rotation and fertilization in the loess plateau Ⅱ. Relationship between soil enzyme

The correlation between soil enzyme activities and other soil properties was studied. The results of correlation analysis showed that soil organic C was correlated very highly significantly with urease activity (r=0.9384^**), alkaline phosphatase activity (r=0.7854^**), and protease activity (r=0.9105^**), and the interrelationship between catalase, invertase activities and organic C content varied with fertilization and cropping patterns. The amount of fungi was significantly correlated with urease and protease activities, and the yield of winter wheat was significantly correlated with urease, alkaline phosphatase and protease activities except catalase. In this paper, the relationship between soil enzyme activities and nutrient factors and the effects of soil enzyme activities on soil nutrient content were analyzed by Principal Components Analysis (PCA) and Path Analysis (PA). According to the results of PCA, urease, alkaline phosphatase, and protease activity could be a better index to evaluate soil fertility in dry land than catalase and invertase activity.