不同有机肥施用量对苹果园土壤养分及酶活性的影响
Effects of Different Organic Fertilizer Amounts on Soil Nutrient and Enzyme Activity of Apple Orchard

为探究有机肥施用量对土壤养分及酶活性的影响，以10年生‘富士’苹果为材料，设置不同有机肥施用量，研究其对土壤养分及酶活性的影响。结果表明，施用有机肥能不同程度地提高土壤有机质、碱解氮、速效磷及速效钾含量和土壤过氧化氢酶、蔗糖酶、脲酶、磷酸酶活性，且随着施肥量的增加而增大。其中，75 kg？株-1施肥处理下0~20、20~40 cm和40~60 cm土层土壤有机质含量分别为16.85、13.23、9.17 g？kg-1，分别比CK增加37.89%、31.12%、16.96%，且该施肥处理的土壤有机质含量与100 kg？株-1处理无显著差异；75 kg？株-1施肥处理下0~20、20~40 cm和40~60 cm土层土壤碱解氮含量分别为73.50、54.83、35.00 mg？kg-1，分别比CK增加65.80%、80.78%、87.47%；在0~20 cm土层，75 kg？株-1施肥处理的土壤速效钾含量为85.03 mg？kg-1，与100 kg？株-1处理无显著差异，但显著高于50、25 kg？株-1处理和CK，比CK增加25.90%。在0~20、20~40 cm和40~60 cm土层，75 kg？株-1施肥处理的蔗糖酶活性分别为16.35、13.00、8.56 mg？g-1？d-1，分别比CK提高21.92%、34.85%、28.92%，蔗糖酶活性显著高于50 kg？株-1和25 kg？株-1处理和CK；在0~20 cm和20~40 cm土层，75 kg？株-1施肥处理的土壤脲酶活性分别为1.42、0.55 mg？g-1？d-1，分别比CK提高115.15%、44.74%，脲酶活性显著高于50、25 kg？株-1处理和CK，但与100 kg？株-1处理无显著差异。综合分析比较，施用有机肥75 kg？株-1对提高土壤综合肥力效果较好。
In order to explore the effects of organic fertilizer amount on soil nutrient and enzyme activity,10-year-old ‘Fuji’ apple trees were used as research objects.Different amounts of organic fertilizer were applied to study the effects on soil nutrient and enzyme activity.The results showed that the application of organic fertilizer could increase the soil organic matter,alkali nitrogen,available phosphorus and available potassium,and promote soil catalase,sucrase,urease and phosphatase activities,and demonstrated amount-dependence effect:100 kg of organic fertilizer per tree>75 kg>50 kg>25 kg>control.Among them,the soil organic matter contents in 0-20,20-40 and 40-60 cm soil layers under fertilization treatment of 75 kg per tree was 16.85,13.23,and 9.17 g？kg-1,respectively,increased by 37.89%,31.12%,16.96% compared with the control.There was no significant difference in soil organic matter content between 75 and 100 kg per tree treatment.The soil alkali nitrogen contents in 0-20,20-40 and 40-60 cm soil layers under 75 kg treatment were 73.50,54.83,and 35.00 mg？kg-1,respectively,increased by 65.80%,80.78%,87.47% compared with the control.The soil available potassium content in the 0-20 cm soil layer with 75 kg treatment was 85.03 mg？kg-1,and had no significant difference with 100 kg treatment,but significantly higher than 50 and 25 kg treatments,as well as the control,25.90% higher than the control.In the 0-20,20-40 and 40-60 cm soil layers,the soil invertase activity of 75 kg treatment was 16.35,13.00,and 8.56 mg？g-1？24 h-1,respectively,increased by 21.92% ,34.85% and 28.92% compared with the control,the invertase activity was significantly higher than 50 and 25 kg treatments and the control.In the 0-20 and 20-40 soil layers,the soil urease activities of 75 kg treatment were 1.42 and