European Journal of Soil Science最新文献

Grassland degradation poses serious threats to global carbon sequestration capacity and the provision of ecosystem services. This study investigates how pristine and iron-modified biochar derived from apple wood (ABC) and rice straw (RBC) influence soil carbon dynamics and ryegrass (Lolium perenne L.) growth in degraded grassland soils. Four biochar treatments (ABC, RBC, Fe-ABC, and Fe-RBC) were tested in a field-scale experiment. Results showed that all biochar amendments increased soil organic carbon (SOC) content, particularly in the Fe-ABC treatment which showed 211% more SOC than the control. Iron-modified biochars (Fe-ABC and Fe-RBC) significantly enhanced plant root length, plant height, and underground dry biomass. However, unmodified ABC achieved the largest carbon pool management index (CPMI = 169.49 ± 16.70), a key indicator that evaluates both the size (storage) and the activity (lability) of the soil carbon pool. This result demonstrates an optimal balance between SOC stabilization and labile carbon maintenance. The Fe-ABC treatment reduced soil inorganic carbon (SIC) content by 23.5%, attributable to carbonate dissolution via acidification (pH decreased from 8.26 to 7.77) and potentially enhanced plant uptake of the dissolved inorganic carbon derivatives. Our findings underscore the importance of application-oriented biochar selection. For degraded grasslands, Fe-ABC was the superior option due to its enhanced capacity for stable SOC formation. Conversely, Fe-RBC demonstrated greater potential for rapid vegetation restoration and productivity enhancement. When a balanced approach to carbon storage and lability is required, ABC emerged as the most suitable amendment, effectively increasing carbon storage without inducing inertness.

The difference between “Pedology” and “Soil Science” is not simply a matter of terminology; it is fundamentally connected to how varied disciplines define their missions, address new emerging challenges, or interact within the scientific, socioeconomic, and cultural landscape at every level (regional, national, and international). This opinion paper aims to initiate a discussion on critically examining whether the continued parallel use of these two terms remains justified in the current scientific context. By considering both the historical context from which we come and future challenges, the article—while acknowledging the undeniable historical and conceptual value of “Pedology”—raises the issue of how its use can become limiting in an era marked by a growing drive toward interdisciplinary collaboration, multidisciplinarity, and ongoing technological innovation. The paper discusses, not claiming to possess the whole truth but simply aiming to open a broader debate, how the univocal adoption of “Soil Science” could serve as a unifying and accessible term, capable of (i) reflecting the current breadth and complexity of the discipline (from biochemical processes to landscape management, food security, and the crucial role of soils in combating climate change) and (ii) ensuring greater inclusiveness and communicative clarity for researchers, professionals, students, policymakers, and society as a whole. The article proposes a shift in language that aligns with current practices in major international journals, scientific societies, international calls, and educational settings at all levels. While honouring the undeniable pedological heritage of the past, such a shift would allow the soil science community to achieve greater recognition on the international stage. In this context, several recommendations are made to foster more balanced and future-oriented terminology for a discipline at the crossroads of tradition and transformation. Without any claim to finality, the paper aims to foster an open and transparent dialogue, encouraging a broad and meaningful cultural debate.

Widespread adoption of conservation practices is increasingly encouraged to improve soil organic carbon (SOC) storage and mitigate climate change. However, soil texture and mineralogy cause variable SOC responses under conservation tillage. The role of minerals and organic carbon composition in soil aggregation and SOC stabilization remains insufficiently understood. This study evaluated the long-term effects of conservation tillage (no-tillage with straw return, NTS) versus conventional tillage (plough tillage with straw removal, CT) on carbon storage across Phaeozems, Calcaric Cambisols, and Calcic Luvisols. Compared to CT, NTS increased the annual average C sequestration rate by 15.3%–76.7% and SOC storage by 10.2%–28.4% in different soil types. NTS also increased macroaggregate percentage and mean weight diameter (MWD), resulting in 17.8%–28.3% larger macroaggregate-associated SOC and total nitrogen (TN) contents. Notably, the aromatic-C/aliphatic-C ratio under NTS increased in bulk soil and macroaggregates, which were positively correlated with larger amorphous iron (Feo) content, Ca²⁺ concentration, and specific surface area in different treatments. Phaeozems exhibit the largest SOC storage, along with larger Feo and Ca²⁺ contents and aromatic-C/aliphatic-C ratio. However, NTS led to the greatest increases in MWD and SOC storage in Calcaric Cambisols, and the greatest enhancement of microbial biomass carbon in Calcic Luvisols. PLS-PM analysis indicated that although the aromatic-C/aliphatic ratio directly enhances aggregated stability, Feo and Ca²⁺ promoted MWD indirectly by facilitating greater aromatic-C and polysaccharide-C. Overall, conservation tillage promoted selective binding of Feo and Ca²⁺ to SOC functional groups, thus enhancing soil aggregation and SOC physico-chemical protection, with calcareous soils showing a stronger response.

Classical soil phosphorus (P) chemistry is based on the belief that fertiliser P precipitates as isolated iron, aluminium and calcium compounds, an opinion encouraged by fractionation schemes and textbook dogma. However, years of evidence indicate the paradigm to be incorrect. Evidence indicates that P rather gets adsorbed onto variable-charge surfaces with subsequent penetration into particles, causing hysteresis in low-P soils and reducing fertiliser effectiveness with time. As P accumulates in soils, hysteresis decreases and fertiliser efficacy stabilises. Likewise, long-held supposition concerning the most favourable soil pH for crop growth and the role of phosphate-solubilising bacteria is found to be misleading when the direct measurement of plant uptake is interrogated. Through the exposure of such misconceptions, we contend that there is a new paradigm of soil P chemistry that more satisfactorily explains experimental observations and informs sustainable fertiliser management.

Soil inorganic carbon (SIC) plays a critical role in the global carbon cycle, particularly in arid and semi-arid regions in which SIC reserves are substantial. However, the mechanisms governing SIC migration and transformation remain poorly understood. This study comprehensively reviews the influence of soil weathering, respiration, depth, precipitation, and acidity on SIC dynamics. We highlight the role of vegetation restoration in enhancing SIC storage and shifting the interactions of soil organic carbon (SOC) with SIC. The solubility changes of CO₂ and carbonates, mineral surface adsorption, and soil chemical reactions are regulated by various environmental factors, substantially affecting CO₂ flux. Yet the carbonate crystals left behind by evaporation during the downward migration of SIC in the soil solution can lead to soil stratification. Furthermore, vegetation restoration boosts carbon storage by adding organic matter through humus and potentially increasing SIC. Our findings reveal that SIC contributes significantly to carbon sequestration, with implications for mitigating climate change. This review provides a framework for better understanding SIC dynamics and its potential for enhancing soil carbon storage in arid ecosystems.

Accurately describing bi- or multi-modal soil hydraulic properties (SHPs) is essential for understanding soil water flow processes. Traditional bimodal models, based on capillary theory, often require numerous empirical parameters and fail to adequately represent macropore flow driven by gravity and film flow held by adsorption forces. In this study, we introduce a novel framework to describe bimodal SHPs by shifting from a reference unimodal model. We propose a new bimodal soil hydraulic model based on the widely used unimodal van Genuchten–Mualem (VGM) model and incorporate the additional effects of adsorption forces. The so-called VGM-Bi model introduces two additional parameters, which can be easily derived or constrained from the measured soil water retention curve (SWRC), enhancing its usability. We further propose a modified version, the VGM-Bi-Macro model, to account for macropore effects by using a hydraulic conductivity value at a slightly negative matric potential as a new matching point. Evaluation with 25 soil samples shows that the VGM-Bi model accurately captures bimodal SWRCs but struggles with bimodal hydraulic conductivity curves (HCCs) for a few samples. In contrast, the VGM-Bi-Macro model effectively captures both. Specifically, the VGM-Bi-Macro model achieves a slightly lower mean root-mean-square error (RMSE) of 0.200 in estimating HCCs and nearly half the RMSE (0.008 cm³ cm⁻³) in estimating SWRCs compared to the VGM-Bi model (0.229 and 0.014 cm³ cm⁻³) and an existing bimodal model (0.262 and 0.015 cm³ cm⁻³), underscoring the importance of gravity-driven macropore flow. These models offer a physically meaningful and efficient tool for simulating water flow in structured soils.

Despite being key indicators of soil fertility and quality, microbial enzyme activities are rarely assessed spatially due to the high number of samples required and labour-intensive assays. This study aimed to evaluate the potential of on-the-go visible–near infrared (vis–NIR) spectroscopy to predict and map the spatial distribution of β-1,4-glucosidase (BG), acid phosphatase (ACP), alkaline phosphatase (ALP), and arylsulphatase (ARS) activities. An on-the-go (tractor-pulled sensor platform) vis–NIR spectroscopy sensor, coupled with partial least squares regression (PLSR), was used to estimate microbial enzyme activities in two fields, namely, Cayenne and Mortier, Belgium. Spatial maps were developed for both measured and predicted enzyme activities and analyzed using Local Moran's I and Bivariate Moran's I spatial statistics. Results showed strong correlations between total organic carbon (TOC), pH, and enzyme activities for samples from these two sites. A notable negative correlation existed between soil pH and TOC. PLSR model prediction accuracy varied by enzyme, with the highest for ARS (R² = 0.70, ratio of performance to interquartile distance [RPIQ] = 2.79), followed by BG (R² = 0.69, RPIQ = 2.93), ACP (R² = 0.64, RPIQ = 2.95), and ALP (R² = 0.60, RPIQ = 1.81). Spatial analysis demonstrated a strong agreement between measured and predicted enzyme activity maps, except for ARS in the Mortier field. Bivariate Moran's Iindicated positive spatial correlations between observed and predicted enzyme activities. In the Cayenne field, the highest Bivariate Moran's I was 0.64 for ACP, while in the Mortier field, the highest value was 0.58 for ALP. Overall, PLSR models performed better in the Cayenne field; hence, spatial predictions of enzyme activities were generally reliable, except for ARS in the Mortier field. These findings demonstrate that on-the-go line vis–NIR spectroscopy can provide reliable, high-resolution maps of soil microbial activities, offering a practical tool for guiding precision fertilizer recommendations.

To address complex challenges and help advance a systems theory for soils requires soil scientists to be able to engage with knowledges outside the discipline of soil science. However, there is a lack of examples and guidance available to support different ways of producing new knowledge. Drawing on our experience as a transdisciplinary team, we present a roadmap comprising five key steps for undertaking transdisciplinary, soil-centred research. The five steps are: addressing complex challenges, building relationships, weaving knowledges and building connectivity, developing holistic understandings and moving beyond knowledge translation. The central tenet of the roadmap is connectivity, with soil health at the core of the interrelationships of people, soil and food. To illustrate the application of this roadmap, we share learnings from two case studies that focused on understanding connections between people and soil, through food production in an Aotearoa New Zealand context. These case studies weave together mātauraka Māori (Māori Indigenous knowledge) and soil science, guided by social science framings, providing examples of how to undertake Transdisciplinary Research (TDR) and guidance for others looking to extend the boundaries of our field by connecting and applying new approaches to knowledge creation, and in so doing advance the development of a soil systems approach.