长期定位施肥对菜田土壤微生物及酶活性的影响

Effect of Long-term Fixed Fertilization on Soil Microbe and Enzymatic Activity

为探讨长期定位施肥对不同菜田-蔬菜生产体系土壤生物肥力的影响,在沈阳农业大学长期定位施肥试验站中选取5个代表性处理,模拟了蔬菜施肥的不同生产体系:维持平衡体系(BN0)、肥力破坏体系(BN2)、逐年减产体系(AN0)、高肥中产体系(AN2)、高产稳定体系(ANK),对土壤微生物变化及酶活性进行分析。结果表明,5种处理的土壤微生物数量均在盛果期达到最高峰,不同酶的活性受季节及番茄生育时期影响动态变化趋势不同,并且不同处理之间土壤微生物数量和酶活性差异显著。高产稳定体系(ANK)可显著提高土壤微生物数量和酶活性,纤维素酶活性为26.10mg.10g-1.72h-1,脲酶活性为29.06mg.100g-1.24h-1,蛋白酶活性为0.703mg.g-1.24h-1;肥力破坏体系(BN2)的土壤细菌数量、脲酶、过氧化氢酶、蛋白酶活性都较维持平衡体系(BN0,CK)显著降低,土壤生物肥力已达到破坏程度。ANK处理产量最高,为38.32kg.plot-1。综合分析表明,在本试验条件下ANK处理土壤生物特性最优。

The effects of long-term fixed fertilization on soil biological fertility were studied under different field-vegetable production systems： maintainable and balanced system, fertility-damaged system, yield-reduction system, well-fertilized and medium-yield system and high-yield and stable system, Five typical production systems （treatments） were selected from the long-term fertilization experiment station at Shenyang Agricultural University. Soil biological characteristics and yield affected by fertilization on soil were analysed. Maximum level of the soil microbial activities were found at fruit stage and the results also indicated there were significant effects of season and growth stages of tomato on soil microbes and enzyme activities. The numbers of bacteria, fungi and actinomycetes and values of enzyme activities were significantly higher in high-yield and stable system （ANK）, with cellulase activity of 26.10 mg-10g^-1·72h^-1, urease activity of 29.06mg·100g^-1·24h^-1, and protease activity of 0.703mg·g^-1·24h^-1.The number of bacteria and activities of urease, catalase and protease in fertility-damaged system（BN2）were found significantly lower than those in maintainable and balanced system （BN0,CK）. The soil biological fertility of （BN2）had been damaged. The highest yield in ANK was 38.32kg·plot^-1. The ANK treatment is the best system with high and stable yield in the long-term fertilization trial.