论文部分内容阅读
测定了1年、10年、18年、32年的杉木林地土壤微生物数量、化学性质、酶活性。结果表明:随着杉木林龄的增长,土壤pH降低,有机质含量增加,土壤中细菌、真菌、氨化细菌、微生物总量呈现“低-高-低”的趋势,放线菌数量变化未表现出明显趋势;水解氮、有效磷、有效钾从幼龄林到中龄林含量有所增加,中龄林以后降低,到成熟林时达到最低;蛋白酶、脲酶、过氧化氢酶、蔗糖酶的活性从幼龄林到中龄林逐渐增强,而在中龄林之后开始下降。随着土层深度的增加,土壤中各种微生物数量、土壤pH、有机质含量、水解氮、速效磷、速效钾以及各种酶的活性均有所降低且趋势较明显。
The soil microbial quantity, chemical property and enzyme activity of 1, 10, 18 and 32 years were measured. The results showed that the soil pH decreased, the content of organic matter increased, the total amount of bacteria, fungi, ammoniated bacteria and microorganism in soil tended to be “low - high - low” with the increase of age of Chinese fir. The content of hydrolyzable nitrogen, available phosphorus and available potassium increased from young to middle age, but decreased from middle age to lowest in mature forest. Protease, urease, catalase, sucrose Enzyme activity gradually increased from young to middle-aged forest, but decreased after middle-aged forest. With the increase of soil depth, the amount of various microorganisms, soil pH, organic matter content, hydrolyzed nitrogen, available phosphorus, available potassium and the activity of various enzymes in soil decreased and tended to be more obvious.