废塑料资源化产品对土壤中过氧化氢酶和脲酶活性的影响(Effect of Waste Plastics Recycling Products on Activities of Soil Catalase and Urease)

为探讨废塑料资源化产品对土壤酶活性的影响,通过室内培养试验研究了废塑料资源化产品暴露后土壤中过氧化氢酶和脲酶活性的变化.结果表明:废塑料资源化产品对土壤酶活性具有显著影响.250mg·kg-1、1250mg·kg-1、7250mg·kg-1废塑料资源化产品浓度处理对土壤中过氧化氢酶和脲酶影响明显不同.在土壤培养l～5d内,添加废塑料资源化产品的3个浓度处理土壤中过氧化氢酶活性显著低于对照(p<0.05),表现出明显的抑制作用,且浓度越高抑制作用越强.而后(5～35d),低浓度(250mg·kg-1)废塑料资源化产品对土壤过氧化氢酶一直表现为激活作用,但是,高浓度(1250mg·kg-1和7250mg·kg-1)处理对土壤过氧化氢酶活性则表现为激活-抑制-激活作用,且抑制、激活程度与处理浓度成呈相关.3个废塑料资源化产品浓度处理对脲酶活性影响在培养1～28d内主要是激活作用,且激活作用随着处理浓度的增大而增强,而后(28～35d)对脲酶活性表现为抑制作用.

Effect of Waste Plastics Recycling Products on Activities of Soil Catalase and Urease

In order to explore the effect of waste plastics recycling products on the activity of soil enzymes, activities of catalase and urease in soil exposed to waste plastics recycling products(250mg·kg-1, 1250mg·kg-1 and 7250mg·kg-1)were determined with indoor culture experiment. Results showed that waste plastics recycling products had significant effect on the activity of soil enzymes. The activity of catalase in three exposure groups was significantly lower than that in the control during incubation for 1～5d. The inhibition rate was increased with the increase of concentrations of waste plastics recycling products. During incubation for 5～35d, low concentration group (250mg·kg-1)exhibited activation effect on the activity of catalase, while high concentration groups (1250mg·kg-1 and 7250mg·kg-1)exhibited activation-inhibition-activation effect on the activity of catalase and the degree of inhibition-activation had a positive relationship with the exposure concentration. During incubation for 1 ～28d, three exposure groups exhibited activation effect on the activity of urease, and the activation rate was increased with the increase of concentrations of waste plastics recycling products. During incubation for 28～35d, three exposure groups exhibited inhibition effect on the activity of urease.