Soil physicochemical properties and soil fertility indicators of two cropping systems under semiarid climate conditions

Abstract

This study evaluated the effects of two long-term cropping systems barley (Hordeum vulgare) and alfalfa (Medicago sativa) on key soil physicochemical and fertility parameters under semi-arid Mediterranean conditions. Soil samples were collected in spring and autumn and analyzed for temperature, bulk density (BD), moisture content (SM), pH, electrical conductivity (EC), calcium carbonate (CaCO₃), soil organic carbon (SOC), and total phosphorus (TP). Soil fertility was further assessed through the carbon-to-phosphorus (C:P) ratio, SOC stock (SOCS), and total phosphorus stock (TPS). Results showed significant effects of crop type and season on several soil properties. Alfalfa, cultivated for over a decade, led to higher SOC, SOCS, and TPS compared to barley, likely due to its continuous cover and nitrogen-fixing capacity. Crop type significantly influenced soil temperature and BD (p < 0.001), while seasonal effects were most evident for SM, EC, and pH. Irrigation practices, identical across both sites, also contributed to soil moisture dynamics. The study highlights that perennial legume cover, such as alfalfa, can improve soil quality by enhancing organic carbon and nutrient stocks. These findings offer valuable insights for sustainable land management and conservation-oriented agriculture in dryland agroecosystems.