Abstract Wood harvesting is restricted to a system of permanent skid trails in order to minimize the soil disturbance and damage. Therefore, it is not the compaction of previously undisturbed forest soil, but the re-compaction of already existing skid trails that is of practical relevance when investigating machinery-induced wood harvest effects on soil properties. This study investigated the effects of machinery-induced re-compaction on soil physical, chemical, and microbiological properties of an old skid trail in a spruce forest by wheeling 8 times with a maximum total load of 32.2 Mg, using a genuine old skid trail as a control. Re-compaction significantly increased the bulk density and reduced the porosity, whereas the soil organic carbon (SOC) and total nitrogen (N) contents were not significantly affected. However, re-compaction reduced the SOC/total N ratio by 10%, suggesting considerable SOC mineralization after re-compaction. K2SO4 extractable C contents were increased by 94% at 0–3 cm and 67% at 7–10 cm depth after re-compaction. This led to 20% and 90% increased microbial biomass C/soil organic C (MBC/SOC) ratios at 0–3 cm and at 7–10 cm depth, respectively. In contrast, the ergosterol/MBC ratio was significantly decreased by 10% at 0–3 cm and by about 30% at 7–10 cm depth by re-compaction, apparently due to the promotion of bacteria and mobilization of soil organic matter.

中文翻译：

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通过重新压实旧森林滑道动员土壤有机质

摘要 木材采伐仅限于永久滑道系统，以尽量减少土壤干扰和破坏。因此，在调查机械引起的木材采伐对土壤特性的影响时，不是压实以前未受干扰的森林土壤，而是重新压实现有的滑道。本研究以最大总载荷 32.2 Mg 为单位，使用真正的老滑道作为轮子，研究了机械诱导的再压实对云杉林中老滑道的土壤物理、化学和微生物特性的影响。一个控制。重新压实显着增加了容重并降低了孔隙率，而土壤有机碳 (SOC) 和总氮 (N) 含量没有显着影响。然而，再压实使 SOC/总氮比降低了 10%，表明再压实后 SOC 矿化显着。重新压实后，K2SO4 可萃取 C 含量在 0-3 cm 处增加了 94%，在 7-10 cm 处增加了 67%。这导致 0-3 厘米和 7-10 厘米深度的微生物生物量碳/土壤有机碳 (MBC/SOC) 比率分别增加了 20% 和 90%。相比之下，通过重新压实，麦角甾醇 / MBC 比率在 0-3 cm 处显着降低 10%，在 7-10 cm 深度处降低约 30%，这显然是由于细菌的促进和土壤有机质的动员。这导致 0-3 厘米和 7-10 厘米深度的微生物生物量碳/土壤有机碳 (MBC/SOC) 比率分别增加了 20% 和 90%。相比之下，通过重新压实，麦角甾醇 / MBC 比率在 0-3 cm 处显着降低 10%，在 7-10 cm 深度处降低约 30%，这显然是由于细菌的促进和土壤有机质的动员。这导致 0-3 厘米和 7-10 厘米深度的微生物生物量碳/土壤有机碳 (MBC/SOC) 比率分别增加了 20% 和 90%。相比之下，通过重新压实，麦角甾醇 / MBC 比率在 0-3 cm 处显着降低 10%，在 7-10 cm 深度处降低约 30%，这显然是由于细菌的促进和土壤有机质的动员。