Land use change (LUC) can alter the soil quality and lead to soil degradation or soil conservation depending on the management practices. In the Mediterranean region, the impact of LUC on soil quality has been well described on neutral or alkaline soils, which are the most common in the area. However, some areas in the west of the Iberian Peninsula are covered by Raña surfaces, a continental detritic formation associated with quartzitic ranges and characterized by very acid and weathered soil. Seven following land uses were selected for this study: cork oak climax vegetation (Cork Oak), pine afforestation (Pine), natural revegetated shrubland (Shrub) and grassland (Grassland) after land abandonment, tilled olive grove (Olive), tilled annual cropland for animal forage (Tillage) and the same annual cropland managed by no-tillage (No-Tillage). The two tree-based uses, Pine and Cork oak, accumulated the highest contents of carbon (C) and nitrogen (N) fractions. However, the further acidification and the C accumulation in labile forms of Pine could hinder the feasibility of Pine plantations to restore acid and degraded soils. Instead, the natural revegetation succession after land abandonment (first Grassland and then Shrub) were found as a suitable alternative able to increase the C content and restore the microbial activity in comparison with Tillage and Olive, the two land uses which showed the lowest C and N content and reduced microbial activity. Furthermore, the improved aggregate stability in Shrub, probably caused by root exudates of dominant plant species, could play a key role in soil restoration. Microbial biomass C and N, C decomposability and enzymatic activities were the most sensible microbial indicators to discriminate among the studied land uses. A clear pattern of lower microbial biomass and enzymatic activity was found with increasing human intervention and soil disturbance. In this respect, soil managed by no-tillage contained higher soil C and N contents when compared to Tillage and the microbial indicators were comparable with those obtained under Cork Oak. Our results demonstrate that soil tillage reduction is an essential step to mitigate soil degradation in Raña soils and highlighted the suitability of No-tillage as an alternative to traditional tillage, which can increase crop productivity while building soil organic matter content. In addition, the natural soil revegetation, including natural grasslands, shrublands and climax cork oak vegetation are more preferable for degraded soil improvement when compared to pine plantations.

土地利用变化（LUC）会改变土壤质量，并导致土壤退化或土壤保持，这取决于管理做法。在地中海地区，LUC对土壤质量的影响已在该地区最常见的中性或碱性土壤上得到了很好的描述。但是，伊比利亚半岛西部的某些地区被拉纳覆盖表面是大陆性的碎屑岩，与石英岩范围有关，其特征是酸性和风化的土壤。本研究选择了以下七个土地用途：软木橡树高潮植被（Cork Oak），松树造林（Pine），废弃土地后的天然植被（灌木）和草地（Grassland），耕种的橄榄树林（Olive），耕种的一年生农田用于动物饲草（耕作），并通过免耕管理相同的年度耕地（免耕）。松树和软木橡树这两种基于树的用途积累了最高的碳（C）和氮（N）含量。但是，进一步酸化和不稳定形式的松树中碳的积累可能会阻碍松树人工林恢复酸和退化土壤的可行性。代替，发现与弃耕和橄榄相比，弃耕后的自然植被恢复演替（先是草地，然后是灌木）是能够增加碳含量和恢复微生物活性的合适替代品，两种土地利用方式均显示出最低的碳和氮含量并降低了微生物活性。此外，可能由优势植物物种的根系分泌物引起的灌木丛中总体稳定性的改善可能在土壤修复中起关键作用。微生物生物量碳和氮，碳的可分解性和酶活性是区分所研究土地用途的最明智的微生物指标。随着人类干预和土壤干扰的增加，发现了较低的微生物生物量和酶活性的清晰模式。在这方面，与免耕相比，免耕管理的土壤含有较高的土壤碳和氮含量，微生物指标可与软木橡树获得的相当。我们的结果表明，减少土壤耕作是缓解Raña土壤中土壤退化的必不可少的步骤，并强调了免耕作为传统耕作的替代品的适用性，传统耕作可以提高作物生产力，同时提高土壤有机质含量。此外，与松树人工林相比，包括天然草地，灌木丛和高潮软木橡树植被在内的天然土壤植被更适合退化土壤改良。我们的结果表明，减少土壤耕作是缓解Raña土壤中土壤退化的必不可少的步骤，并强调了免耕作为传统耕作的替代品的适用性，传统耕作可以提高作物生产力，同时提高土壤有机质含量。此外，与松树人工林相比，包括天然草地，灌木丛和高潮软木橡树植被在内的天然土壤植被更适合退化土壤改良。我们的结果表明，减少土壤耕作是缓解Raña土壤中土壤退化的必不可少的步骤，并强调了免耕作为传统耕作的替代品的适用性，传统耕作可以提高作物生产力，同时提高土壤有机质含量。此外，与松树人工林相比，包括天然草地，灌木丛和高潮软木橡树植被在内的天然土壤植被更适合退化土壤改良。