Soil Productivity Degradation in a Long-Term Eroded Olive Orchard under Semiarid Mediterranean Conditions

Olive groves are one of the most important agro-systems in the Mediterranean basin, and<br> the Andalusia region produces the highest quantity of olive oil in Europe. The aim of this work<br> was to evaluate the long-term (15 years) influence of two management practices in olive orchards—<br> conventional tillage (CT) and no tillage with bare soil and herbicide application (NT + H)—on<br> soil physical properties, infiltration capacity, erosion rates, and soil productivity. In addition, the<br> short-term (2 years) influence of no tillage with cover crop management (NT-CC) on these parameters<br> was also assessed. In the study area, CT and NT + H management practices showed unsustainable<br> erosion values, 9.82 and 13.88 Mg ha􀀀1 year􀀀1, respectively, while NT-CC inclusion decreased the<br> erosion rates (2.06 Mg ha􀀀1 year􀀀1). The implementation of NT-CC not only reduced erosion rates<br> but also caused a change in the trend of soil productivity loss observed under CT and NT + H. In<br> this sense, NT-CC showed a positive influence on soil quality. However, tillage removal led to a<br> significant reduction in the infiltration capacity of soils under NT + H and NT-CC, which will be a<br> serious handicap for water storage in an environment with continuous processes of water deficit.橄榄园是地中海盆地最重要的农业生态系统之一，而安达卢西亚地区的橄榄油产量居欧洲首位。本研究旨在评估橄榄园两种管理措施——传统耕作（conventional tillage, CT）以及裸土喷施除草剂免耕（no tillage with bare soil and herbicide application, NT + H）——的长期（15年）效应，考察指标涵盖土壤物理性质、入渗能力、侵蚀速率与土壤生产力。此外，本研究还评估了覆盖作物免耕（no tillage with cover crop management, NT-CC）的短期（2年）效应对上述参数的影响。 在研究区域内，CT与NT + H两种管理措施的侵蚀速率均处于不可持续水平，分别为9.82与13.88 吨·公顷⁻¹·年⁻¹；而采用NT-CC后，侵蚀速率降至2.06 吨·公顷⁻¹·年⁻¹。 实施NT-CC不仅降低了侵蚀速率，还扭转了CT与NT + H管理模式下观测到的土壤生产力下降趋势。据此而言，NT-CC对土壤质量具有积极影响。然而，取消耕作导致NT + H与NT-CC处理下的土壤入渗能力显著下降，这在持续缺水的环境中会成为土壤储水的严重阻碍。