陇东黄土丘陵沟壑区山坡地人工沙棘林地土壤酶活性的季节性变化规律

The Seasonal Change of Soil Enzyme Activity of Artificial Hippophase Forest in Slope Land of Gully-hilly Loess Plateau, Northern China

陇东黄土丘陵沟壑区沙棘人工林分的年生长、土壤养分、土镶酶活性三者之间相互关联、相互影响，并均存在着季节性变化规律。研究结果表明：沙棘的年生长过程与脲酶、磷酸酶等转化土壤速效养分的酶活性季节变化规律相同，都为“夏高型”；转化酶、脱氢酶、过氧化氢酶、多酚氧化酶等与土壤有机质形成有关的酶活性季节变化规律为“秋高型”。土壤速效养分的季节变化规律为“夏低型”，夏季沙棘人工林分的年生长高峰造成了此时土壤速效养分较低的现象，而土壤酶的酶促作用又使得沙棘年生长结束时的土壤速效养分基本上恢复到年初水平，沙棘林分的自肥作用很好。

The yearly growth amount, soil nutrient, and soil enzyme activity of artificialhippophase forest existed interrelation each other, also possessed seasonable change law. Theresults show, the yearly hippophase growth process law was relationship with seasonal change ofsoil enzyme such as urease and phosphatase. The change law of soil sucrase, dehydrase, andcatalase related with soil organic matter formation is higher peak value in autumn. The seasonablechange law of soil available nutrient is lower peak value in summer.