柠条林地土壤酶活性特征研究

Characters of soil enzyme activities of Caragana Korshinskii Kom.forest land

对固原县上黄试区柠条林地土壤酶（脲酶,碱性磷酸酶,蔗糖酶）的活性进行测试分析,分析比较不同坡向、不同坡位、不同林龄和不同剖面深度条件下酶活性的变化。结果表明：坡向对土壤酶活性的影响不显著;坡位对土壤酶的活性有明显的影响,坡上部酶活性普遍高于坡下部,坡中部酶活性波动较大;土壤酶活性随林龄的增大而提高,10年生柠条林地平均脲酶、蔗糖酶和磷酸酶的活性分别仅为20年生柠条林地相应酶活性的59.0%、41.1%和52.9%;土壤酶活性随土壤剖面深度的增加而降低,20年生柠条20-40 cm4、0-60 cm和60-80 cm土层的脲酶活性分别比0-20 cm表层土脲酶活性下降25.7%、61.3%和81.4%;碱性磷酸酶与蔗糖酶在有机质腐殖化过程中具有协同反应,关系密切。

Discussion is made about the characters of soil enzyme（urease,phosphatase,ucrase） activities of Caragana Koeahinakii Kom.forest land at Shanghuang experimental field in Guyuan County and comparison is conducted of the enzyme activities of different slope aspects,different slope positions,different tree ages and different depths of soil profile.The results showed that slope aspects had no notable influence on soil enzyme activities but the slope positions influenced obviously the soil enzyme activities,and the enzyme activities of the upper slope positions are generally higher than lower slope positions.The soil enzyme activities enhanced as the tree ages increasing and fell down as the depth of soil profile increasing.The phosphatase and ucrase had concerted reaction during the humification of soil organic matter.