European Journal of Soil Science最新文献

The global decline in soil phosphorus (P) availability presents a significant threat to food security, necessitating a re-evaluation of phosphorus deficiency in soils and an urgent focus on activating legacy phosphorus reservoirs. Phosphorus deficiency is typically addressed through two main strategies: the Limiting Factor Principle, which emphasizes direct mineral P supplementation, and Systems Theory, which advocates for soil elemental stoichiometry driven by microorganisms. However, it remains unclear which strategy is more effective in improving P availability and long-term soil health, a gap that may impact soil management practices. To address this, we conducted an incubation experiment with soil subjected to 23 years of localized fertilization management. Our results showed that P amendment alone did not resolve phosphorus deficiency, while C amendment, either alone or in combination with P, effectively promoted P activation and enhanced microbial functionality. Microcalorimetric analyses indicated that exogenous organic carbon increased microbial biomass and stimulated metabolic activity and alkaline phosphatase activity, particularly in P-deficient soils, thereby enhancing organic P mineralization and mobilization. Additionally, shifts in soil microbial communities were observed, characterized by increased relative abundances of Comamonadaceae and Bacillus. Both taxa are known for their strong responsiveness to carbon availability, suggesting their potential role in coupled carbon-phosphorus phosphate cycling. These findings indicate that Systems Theory, improving the soil health of P-deficient soils through both soil functions and soil life, provides a complementary strategy to traditional fertilization for improving P-deficient soils.

Sub-surface soil compaction restricts root growth and water movement in intensively cultivated semi-arid croplands. Chiselling is commonly used to alleviate compaction, but its effects are often short-lived under variable rainfall conditions. We evaluated the time-variable effects of chiselling on soil hydro-mechanical properties (penetration resistance [PR], bulk density [BD], hydraulic function [steady-state infiltration, IR; field-saturated hydraulic conductivity, K_fs] and soil moisture dynamics), root traits (length, volume, surface area and diameter), yield and water use efficiency (WUE) in a soybean-wheat rotation on a sandy loam soil over 2 years. Four treatments were evaluated: residual chisel (RS; May 2011), repeated chisel (RC; May 2011 and May 2013), fresh chisel (FC; May 2013), and no chisel (NC). At early soybean 2013, the compact layer (15–30 cm) showed 20%–22% lesser PR in RS and RC than NC (p = 0.019); BD reductions mirrored this pattern. Despite greater PR, NC initially exhibited the highest IR (1.36 cm h⁻¹ vs. RS 0.79, RC 1.08, FC 0.90 cm h⁻¹) and K_fs (1.10–1.19 cm h⁻¹, 31%–82% above chiselled plots at 15–30 cm), consistent with a dual-porosity mechanism in which a few continuous biopores govern near-saturated flow while the surrounding matrix remains strong. Root responses concentrated at 15–30 cm. RS/RC increased root length, volume and surface area and moderately enlarged mean diameter relative to NC/FC (p < 0.05). Yield gains and improved WUE were observed in soybean in year 1 under RS (21% and 10%) and RC (32% and 17%) versus NC, whereas wheat yield did not differ; WUE was modest. Rainfall timing explained the short-lived FC gains. The first 14 days after chiselling (20 May 2013) were dry, followed by two storm clusters within days 15–60 totaling ~330 mm, including ≥ 50–100 mm single-day events. These high-load, antecedently wet events plausibly collapsed freshly created voids in FC, truncating hydraulic gains, while RS/RC retained some storage advantages. The findings highlight that the effectiveness of chiselling is strongly time- and rainfall-dependent, and their persistence depends on pore-network continuity. Results suggest site-specific, rainfall-informed tillage decisions to enhance soil structural resilience and sustainable productivity in semi-arid systems.