Abstract Inorganic fertilizers have been reported to have effects on both microbial activities and soil microbial community structure. However, the published results are often contradictory. To overcome short-term fluctuations in microbial parameters it is necessary to study their changes over the long term. We investigated the impact of a 40-y inorganic fertilization of a grassland field on selected soil microbial enzymatic activities and on the composition of bacterial and fungal communities, assessed by terminal restriction fragment length polymorphism (T-RFLP). The following fertilizer treatments were compared: C (control, no fertilization), PK (phosphorus and potassium) fertilizer, 80N (lower nitrogen plus PK fertilizer) and 160 N (higher nitrogen plus PK fertilizer). The field trial also included a NF treatment where fertilization with high nitrogen doses was terminated after 20 y, and the subsequent 20 y were under a non-fertilization regime. Except for arylsulfatase, addition of PK was not sufficient intervention to influence enzyme activities. On the contrary, we observed a significant increase in cellobiosidase, phosphomonoesterase, and β-glucosidase activity in soils fertilized with N, although there was no difference in the enzyme activities between the 80N and 160N treatments. The activities of these enzymes in soils under NF treatment returned to the values of the control soils. Decreased activity of arylsulfatase was detected in treatments with fertilization compared to the control treatment. The shifts in the enzyme activities were accompanied by changes in the composition of whole bacterial and fungal communities, which was also affected by the long-term fertilization. Community composition in fertilized soils clearly differed from the control soils. Contrary to bacteria, 20 y following the cessation of fertilization in the NF treatment was not enough time for complete recovery of the fungal community to that observed in the control treatment. Our findings suggested that soil bacteria are more resilient to chemical fertilization disturbances than fungi.

中文翻译：

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矿物施肥下 40 年田间试验土壤微生物群落的变化和恢复

摘要 据报道，无机肥料对微生物活动和土壤微生物群落结构都有影响。然而，公布的结果往往是矛盾的。为了克服微生物参数的短期波动，有必要研究它们的长期变化。我们通过终端限制性片段长度多态性 (T-RFLP) 评估了草地 40 年无机施肥对选定土壤微生物酶活性以及细菌和真菌群落组成的影响。比较了以下肥料处理：C（对照，不施肥）、PK（磷和钾）肥料、80N（低氮加PK肥）和160N（高氮加PK肥）。田间试验还包括 NF 处理，其中高氮剂量施肥在 20 年后终止，随后的 20 年处于非施肥制度下。除芳基硫酸酯酶外，添加 PK 不足以影响酶活性。相反，我们观察到施氮土壤中纤维二糖苷酶、磷酸单酯酶和 β-葡萄糖苷酶活性显着增加，尽管 80N 和 160N 处理之间的酶活性没有差异。NF处理土壤中这些酶的活性恢复到对照土壤的值。与对照处理相比，在施肥处理中检测到芳基硫酸酯酶活性降低。酶活性的变化伴随着整个细菌和真菌群落组成的变化，这也受到长期施肥的影响。施肥土壤中的群落组成与对照土壤明显不同。与细菌相反，在 NF 处理中停止施肥后 20 年时间不足以使真菌群落完全恢复到对照处理中观察到的水平。我们的研究结果表明，土壤细菌比真菌更能抵御化学施肥干扰。在 NF 处理中停止施肥后 20 年时间不足以使真菌群落完全恢复到对照处理中观察到的情况。我们的研究结果表明，土壤细菌比真菌更能抵御化学施肥干扰。在 NF 处理中停止施肥后 20 年时间不足以使真菌群落完全恢复到对照处理中观察到的情况。我们的研究结果表明，土壤细菌比真菌更能抵御化学施肥干扰。