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We tested the effect of main soil characteristics and tree species on earthworm community composition and abundance in reclaimed spoil heaps planted with five different tree species. Earthworm and soil macroarthropod abundance and biomass were highest in alder plantations, followed by oak plantations. The numbers of soil macrofauna were positively correlated with the total soil N content, which was highest in alder plantation. The correlation was strongest for endogeic earthworms (genus Aporrectodea and Octolasion). Soil moisture, measured in top 10 cm, affected only endogeic species. Other soil variables (pH, Ca) did not have a strong effect on earthworms. The earthworm community composition was similar in alder and oak, with most species occurring at both types of forest; however, in alder forest the epigeic species Dendrobaena octaedra was more common, whilst in oak forest the epigeic earthworms form genus Lumbricus were more abundant (L. rubellus and L. castaneus). The anecic species Aporrectodea longa was more abundant at alder sites, but L. terrestris was more abundant under oak. The alder forest was characteristic by a thick humus layer (10–15 cm), which at oak and larch sites was thinner (4–7 cm) and at pine and spruce stands was absent. Soil compaction was lower under the deciduous trees (alder, oak, larch), than under spruce and pine. We conclude that the alder plantations have most palatable litter and lowest C/N ratio and therefore support the highest numbers of soil macrofauna, which affects the humus layer thickness and soil compaction in the surface layers. [ABSTRACT FROM AUTHOR]

• Based on the results soil organic matter management has a more important effect on sandy soils. • Results showed there was no significant difference in the mean weight of the soil aggregates. • Results showed Luvisols had higher levels of soil organic matter and compaction. • Cambisols managed by long-term tenants were less compact than soils managed by short-term tenants. • The willingness of a farmer to invest in the soil is related to tenure security and the length of the contract. Identifying key drivers of land degradation is essential to mitigate or prevent land degradation, promote land recovery, and achieve improvement at national and international levels. The aim of this study was to test whether the level of land tenure security affects the degree of soil degradation. The level of land tenure security was tested on two contrasting soil types to determine whether the initial soil quality may mitigate the effect of poor management. The following soil degradation indices were selected: soil compaction, soil organic matter content (SOM), and soil aggregate stability, measured as mean weight diameter (MWD), and weight of each size fraction. The soils tested belonged to one of the two soil types: Cambisol (with a sandy loam texture) or Luvisol (with a silt loam texture). Luvisols had higher SOM, macro aggregates, and compaction levels compared with Cambisols. In addition, Luvisols were not related to tenure security. Based on the results, Cambisols were affected by tenure security, and owner-managed soils had the highest SOM content and the lowest soil compaction. In addition, the Cambisols managed by long-term tenants were less compacted than soils managed by short-term tenants, because SOM is a long-term indicator. Therefore, a management practice that has been implemented for less than 10 years will not have a significant impact on this indicator. Owner-operators are likely to retain the soil for a longer period of time than either of the two groups of tenant farmers. Thereby, they would be able to affect the long-term characteristics of the soil better than the tenants. There was no significant difference in the mean weight of the soil aggregates between differently managed soils. This study concluded that the willingness of a farmer to invest in the soil is affected by tenure security and the length of the contract, which may be reflected by the soil quality, especially in nutrient-poor soils. [ABSTRACT FROM AUTHOR]