Forest thinning is a management measure intended to promote forest regeneration and improve soil microbial activity. However, a comprehensive evaluation of the effects of forest thinning on soil microbial biomass and enzyme activity is yet to be conducted. Therefore, this study analyzed 1059 data points from 69 studies at the global scale to investigate the effects of forest type, thinning intensity, recovery time, and mean annual precipitation and temperature on microbial biomass and enzyme activity. Thinning significantly increased the microbial biomass carbon (8.92 %), nitrogen (17.40 %), and phosphorus (29.98 %) levels and saccharase (9.21 %) and urease (10.08 %) activities. The response ratio of soil microbial biomass was higher in coniferous forests than that in broadleaf or mixed forests, and the response ratio of saccharase activity was higher in mixed forests than in coniferous or broadleaf forests. The response ratios of microbial biomass and phosphatase activity were higher in the late recovery time than those in the early and medium recovery times. Soil microbial biomass and enzyme activity first increased and then decreased with thinning intensity but decreased with mean annual precipitation and temperature. In conclusion, this study highlights that thinning significantly increases soil microbial biomass and enzyme activity, and a moderate thinning intensity (33.3–66.6 %) and long-term recovery (>10 years) are highly conducive to improving soil microbial activity. These results provide a basis for forest ecosystem management and the formulation of scientific and reasonable thinning parameters.

中文翻译：

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森林间伐对土壤微生物量和酶活性的影响

森林间伐是旨在促进森林更新、改善土壤微生物活性的管理措施。然而，森林间伐对土壤微生物量和酶活性的影响尚未进行综合评价。因此，本研究分析了全球范围内69项研究的1059个数据点，以探讨森林类型、间伐强度、恢复时间以及年平均降水量和温度对微生物生物量和酶活性的影响。间伐显着增加了微生物生物量碳（8.92%）、氮（17.40%）和磷（29.98%）水平以及蔗糖酶（9.21%）和脲酶（10.08%）活性。针叶林土壤微生物量的响应比阔叶林和混交林高，混交林糖酶活性的响应比针叶林和阔叶林高。微生物量和磷酸酶活性的响应率在恢复后期高于恢复早期和中期。土壤微生物量和酶活性随间伐强度先增后减，随年平均降水量和气温的变化而降低。总之，本研究强调，间伐显着增加了土壤微生物生物量和酶活性，中等间伐强度（33.3-66.6%）和长期恢复（>10年）非常有利于提高土壤微生物活性。这些结果为森林生态系统管理和制定科学合理的间伐参数提供了依据。