The conversion of natural forest to oil palm (Elaeis guineensis Jacq.) plantation is perceived as a threat to biodiversity conservation. The aims of this investigation were to assess variation in soil physico-chemical parameters and macroinvertebrate structures following the conversion of secondary forests to oil palm plantations, and to understand what to expect with the aging of the plantations. We hypothesised that soil properties would be improved with respect to biodiversity conservation with the aging of the oil palm plantations. Sampling was carried out in secondary forests, and in 13-, 20- and 39-year-old oil palm plantations at the La Mé Station, Côte d’Ivoire. Three sampling areas were established in each land-use type and age class, for a total of 12 sampling areas. Over a 50-m transect, litter-dwelling macroinvertebrates were sampled by using pitfall traps, and topsoil (0–10 cm) macroinvertebrates by using monoliths (50 cm by 50 cm by 10 cm), following the modified ‘Tropical soil biology and fertility’ method. Soil physical and chemical parameters were characterised. The results showed that the conversion of secondary forests to oil palm plantations was characterised by changes in soil macroinvertebrate density (–30%), taxonomic richness (–37%) and functional groups (–17%), as well as soil bulk density (+14%) and water content (+16%), after ~39 years of conversion. Soil organic carbon, total nitrogen and organic matter increased with the aging of plantations, and reached conditions similar to those of secondary forests. The human interference imposed on macroinvertebrate communities during site preparation and planting was not compensated by the reduction in the soil-degradation index over time. The results have implications for implementation of conservation agriculture and the related management practices.

天然林向油棕的转化雅克（Jacq。）人工林被视为对生物多样性保护的威胁。这项研究的目的是评估次生林转变为油棕人工林后土壤理化参数和大型无脊椎动物结构的变化，并了解随着人工林老化的结果。我们假设随着油棕种植园的老化，在保护生物多样性方面土壤性质将得到改善。在科特迪瓦LaMéStation的次生森林以及13、20和39年的油棕种植园中进行了采样。在每种土地利用类型和年龄类别中都建立了三个采样区域，总共12个采样区域。在一个50米长的样带上，使用陷阱陷阱对生活在垃圾产地的大型无脊椎动物进行采样，并采用改良的“热带土壤生物学和肥力”方法，使用整料（50 cm x 50 cm x 10 cm）和表土（0-10 cm）的大型无脊椎动物。对土壤理化参数进行了表征。结果表明，次生林向油棕人工林的转化具有以下特征：土壤大型无脊椎动物密度（–30％），分类学丰富度（–37％）和功能组（–17％）以及土壤容重（经过约39年的转换，水含量（+ 14％）和水分含量（+ 16％）。土壤的有机碳，总氮和有机质随着人工林的老化而增加，并达到与次生林相似的条件。随着时间的推移，土壤退化指数的下降并不能弥补在场地准备和种植期间对大型无脊椎动物群落造成的人为干扰。