Tropical montane forests in the Andes are subjected to deforestation and subse-quent transformation into pastures. Abandoned pastures are frequently reforested by planting monoculture timber plantations, resulting in reduced aboveground diversity and changes in soil characteristics compared to primary forests. In this study, we evaluated differences in soil properties (litter layer thickness, pH, water content, and C-to-N ratio) between degraded primary montane forest and monoculture pine (Pinus patula) and alder (Alnus acuminata) plantations and their effects on density, diversity, and community structure of litter and soil-living mesofauna, with focus on oribatid mites (Acariformes). The study was performed in a montane region in the southern Ecuadorian Andes (2,000–2,600 m a.s.l.). C-to-N ratios in the litter and upper 5 cm soil layer were higher in pine plantations, while other soil characteristics were similar between vegetation types. Surprisingly, microbial biomass and density of soil mesofauna in the litter layer did not differ between vegetation types, while density and species richness of oribatid mites were higher in pine plantations. Community structure of oribatid mites differed between vegetation types with only a few species overlapping. The results indicate that quality and diversity of litter were not the major factors regulating the mesofauna community. Instead, soil animals benefited from increased habitat structure in thicker litter layers and potentially increased availability of root-derived resources. Overall, the results suggest that from a soil animal perspective, monoculture plantations are less detrimental than commonly as-sumed and enrichment of abandoned plantations with native tree species may help to restore tropical montane forests.

中文翻译：

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将安第斯山地森林转变为人工林：对土壤特性、微生物和微节肢动物的影响

安第斯山脉的热带山地森林遭到砍伐，随后转变为牧场。废弃的牧场经常通过种植单一的用材林来重新造林，与原始森林相比，导致地上多样性减少和土壤特性发生变化。在这项研究中，我们评估了退化的原始山地森林与单一栽培的松树 (Pinus patula) 和桤木 (Alnus acuminata) 人工林之间土壤特性（凋落物层厚度、pH、含水量和碳氮比）的差异及其影响的密度、多样性和群落结构的垃圾和土壤生活中型动物，重点是 oribatid 螨（Acariformes）。该研究是在厄瓜多尔安第斯山脉南部（海拔 2,000-2,600 米）的山地地区进行的。松林的凋落物和上部 5 厘米土壤层的碳氮比较高，而植被类型之间的其他土壤特征相似。令人惊讶的是，凋落物层中土壤中型动物群的微生物生物量和密度在植被类型之间没有差异，而松林中的螨类密度和物种丰富度更高。不同植被类型的螨类群落结构不同，只有少数物种重叠。结果表明，凋落物的质量和多样性不是调节中型动物群落的主要因素。相反，土壤动物受益于较厚的枯枝落叶层中栖息地结构的增加，以及根系资源的潜在可用性增加。总的来说，结果表明，从土壤动物的角度来看，