子午岭地区植被演替过程中土壤养分及酶活性特征研究

The characteristics of soil enzyme activities and nutrients during vegetation succession

选择植被自然恢复不同年限的阳坡梁坡地作为研究对象,采用时空互代法研究子午岭地区植被恢复过程中土壤养分和酶活性的变化。结果表明,植被恢复140 a内,不同土层土壤有机质含量、全氮含量、蔗糖酶活性、脲酶活性、碱性磷酸酶活性和过氧化氢酶活性增加,且表土层（0-20 cm）土壤养分含量和酶活性高于下层土壤（20-40 cm）。以裸露地为对照,土壤0-20 cm土层,有机质含量、全氮含量、蔗糖酶活性、脲酶活性、碱性磷酸酶活性和过氧化氢酶活性分别增加了23.8%-534.9%、9.3%-300.0%、213.6%-521.5%、40.4%-286.5%、22.7%-232.2%和3.2%-22.4%,土壤速效磷含量呈现波动变化,过氧化氢酶活性变化幅度比其他三种酶低。土壤有机质含量与全氮、速效磷含量密切相关;土壤蔗糖酶与土壤有机质、全氮均为极显著的相关关系（0.930/0.918）;土壤脲酶活性与全氮含量相关系数最高（0.804）;土壤碱性磷酸酶活性与有机质、全氮含量都呈极显著相关（0.977/0.984）;土壤过氧化氢酶活性与全氮含量极显著相关,相关系数达0.996。

Taking research sites located at sunny slop with different years of natural vegetation restoration in Ziwuling area as a case study,dynamic changes of soil nutrient and soil enzyme activities following 140 years of vegetation restoration were analyzed.Results showed that after 140 years of vegetation restoration,soil organic matter（SOM）,total N（TN）,invertase,urease,alkaline phosphates and catalase activities obviously increased in both 0～20 cm and 20～40 cm layers of soil profile with an increase of the vegetation restoration year. Compared with corresponding bare land,SOM,TN,soil invertase,urease,alkaline phosphates and catalase activities in 0～20 cm layer of soil profile increased by 23.8%～534.9%、9.2%～300.0%,213.6%～521.5%,40.4%～286.5%,22.7%～232.2% and 3.2%～22.4%,change trend of soil available P of soil profile was fluctuant,soil catalase activity change scop was lower than other three kinds of enzyme.There was remarkable correlation between SOM and TN,available P;soil invertase activity and SOM,TN assumed significant correlation（0.930 and 0.918）;the correlation coefficient of soil urease activity and TN is the highest（0.804）;there was also very significant correlation between soil alkaline phosphates activity and SOM,TN（0.977 and 0.984）;soil catalase activity and TN also presented remarkable correlation,the correlation coefficient reached to 0.996.