European Journal of Soil Science最新文献

{"title":"Single Superphosphate-P Fractions Influence Bacterial Communities in Wheat Rhizosphere Soil Under Microcosm Conditions","authors":"M. Gutiérrez-Martín,&nbsp;R. Baigorri,&nbsp;S. Rubio-Gracia,&nbsp;R. García,&nbsp;S. San Francisco,&nbsp;M. Caballero,&nbsp;S. Atarés","doi":"10.1111/ejss.70096","DOIUrl":"https://doi.org/10.1111/ejss.70096","url":null,"abstract":"<div>\u0000 \u0000 <p>The water-insoluble phases of phosphate fertilisers have traditionally been considered an agronomic concern because of their phosphorus bioavailability. However, this chemical behaviour with respect to its solubility in soil could be an advantage from the point of view of environmental sustainability, since these phosphates are more stable in soil and less susceptible to blockage by adsorption. Hence, plants could have a long-term bioavailable form of phosphate for their nutrition, which may increase the agronomic performance of the crop. However, these phosphate-based chemical molecules need to be solubilised either by the action of organic compounds exuded by plants or by microorganisms with the capacity to solubilise phosphates. Through the application of phosphorus fractions of different solubilities from single superphosphate (SSP) in soils planted with wheat plants, here we studied plant growth and nutritional content as agronomic response, as well as the influence on the bacterial communities present in the rhizosphere and their potential functionality with 16S rRNA metabarcoding and predictive functional metagenomics (PICRUSt), respectively. Results indicate a direct effect on rhizosphere bacterial communities depending on the nature and solubility of the phosphorus fractions applied. The increase in the amount of bioavailable phosphorus in soil (+1.57 to 2.21 mg·kg⁻¹), together with the increase in bacterial genes related to phosphate solubilisation after the application of slightly soluble or non-soluble forms of phosphate, suggests that the presence of these forms of phosphate may stimulate the activity of phosphate-solubilising microorganisms. However, by comparing rhizosphere soil samples with bulk soil, we observed that plant roots may have a higher impact on edaphic bacterial biodiversity and functionality than the application of different forms of phosphates. Therefore, future studies are needed to elucidate direct actions of phosphate forms on rhizosphere microorganisms, indirect effects caused by plant root exudates and the combined effect of both.</p>\u0000 </div>","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"76 2","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143707276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Soil Organic Matter and Biochar Effects on Soil Water: Measurements, Pedotransfer Functions and APSIM Simulations","authors":"Deborah Aller,&nbsp;Sotirios Archontoulis,&nbsp;David Laird","doi":"10.1111/ejss.70083","DOIUrl":"https://doi.org/10.1111/ejss.70083","url":null,"abstract":"<p>The ability of soils to store and regulate water release to plants is critical for crop production; hence, the ability to estimate soil water parameters is critical. This study aimed to (1) determine biochar effects on the relationship between soil organic matter (SOM) and soil water/physical parameters including field capacity (FC), wilting point (WP), saturation (SAT), water holding capacity (WHC) and bulk density (BD); and (2) evaluate four pedotransfer functions (PTFs) and the APSIM-biochar model for their ability to estimate soil water/physical parameters. Forty-eight deep soil cores were collected from fields with and without biochar applications in Iowa, USA, sectioned into five increments (0–5, 5–15, 15–30, 30–50 and 50–90 cm, <i>n</i> = 226 replicated samples), and analysed for texture, SOM, FC, WP, SAT and BD. For every 1% increase in SOM, the 0–30 cm WHC increased by 5 mm (or 12%). The rate of increase was similar (<i>p</i> = 0.427) for soils with and without biochar, indicating that biochar and biogenic SOM have a similar influence on WHC. Across all data sets, the tested PTFs captured observed data variability, with the Saxton and Rawls PTF having the lowest relative root mean square error (RRMSE). The APSIM-biochar model dynamically simulated changes in soil water parameters and BD response to biochar application with an average RRMSE of 8.3% (uncalibrated) to 6.1% (calibrated). We concluded that the Saxton and Rawls PTF is effective for predicting WHC of soils with and without biochar amendments and that the accuracy of WHC predictions can be improved with location/biochar type-specific calibrations.</p>","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"76 2","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/ejss.70083","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143698852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficiency of Sequential Extraction Schemes in Partitioning Toxic Elements in Acid Sulfate Soils With a Thionic Horizon","authors":"Francis Henrique Tenório Firmino,&nbsp;João Carlos Ker,&nbsp;Maurício Paulo Ferreira Fontes,&nbsp;Jaime Wilson Vargas de Mello,&nbsp;Hidelblandi Farias de Melo,&nbsp;Luiz Felipe Mesquita","doi":"10.1111/ejss.70090","DOIUrl":"https://doi.org/10.1111/ejss.70090","url":null,"abstract":"<p>The use of sequential extraction methods is a common practice for analysing the availability of potentially toxic elements in soils and sediments. However, the simultaneous presence of oxidisable and reducible minerals in acid sulfate soils with a thionic horizon raises questions about the accuracy of these methods. This study focused on the comparative evaluation of two sequential extraction schemes—the modified BCR method (four steps) and the modified Tessier method (six steps) - in acid sulfate soils with a thionic horizon in the Delta of the Doce River region, Espírito Santo, Brazil. With particular attention to the presence of jarosite, a mineral associated with the sulfurization process, specific tests were conducted to better understand the performance of reducible extractors on its synthetic phase. The results highlight the complex dynamics of acid sulfate soils with a thionic horizon concerning the distribution of iron and potentially toxic elements. A significant divergence was observed between the two sequential extraction methods in identifying the main reservoir of potentially toxic elements. In the modified BCR method, metals were primarily associated with oxidizable iron fractions, including organic matter. In contrast, the modified Tessier method indicated metals in the reducible iron fractions, suggesting a different interpretation of the mobility and bioavailability of the elements. The comparative analysis revealed that the modified Tessier procedure is more effective in characterising acid sulfate soils with a thionic horizon for the following reasons: (1) it provides greater precision in evaluating the soil's exchangeable fraction; (2) it avoids underestimating the reducible fraction, capturing the dissolution of sulfide oxidation products; (3) it more accurately identifies elements associated with sulfide minerals; and (4) it offers a more precise quantification of the residual fraction. However, a limitation of the modified Tessier method is the omission of the influence of organic matter, an important component in the dynamics of elements in hydromorphic environments, emphasising the need for complementary approaches for a comprehensive understanding of the availability of potentially toxic elements (trace metal) in such soils.</p>","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"76 2","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/ejss.70090","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pedotransfer Functions Versus Model Structure: What Drives Variance in Agro-Hydrological Model Results?","authors":"Maria Eliza Turek,&nbsp;Johannes Wilhelmus Maria Pullens,&nbsp;Katharina Hildegard Elisabeth Meurer,&nbsp;Edberto Moura Lima,&nbsp;Bano Mehdi-Schulz,&nbsp;Annelie Holzkämper","doi":"10.1111/ejss.70088","DOIUrl":"https://doi.org/10.1111/ejss.70088","url":null,"abstract":"<p>Pedotransfer functions (PTFs) are widely used empirical relationships to estimate soil hydraulic parameters. PTFs are usually derived from point soil samples analysed in the field or laboratory; thus, they contain uncertainties at different levels (i.e., from sampling and measuring techniques, as well as empirical approaches chosen to quantify relationships). When PTFs are used to parametrize agro-hydrological models, both the choice of PTF and the choice of the model may influence the simulation results. Both sources of variance (PTF choice and model structural differences) were found to be relevant in previous studies, but how they relate to each other has rarely been investigated. In this study, we addressed this research gap by conducting a systematic analysis of the variance in selected agro-hydrological model outputs (i.e., seepage water, soil water content, actual evapotranspiration, transpiration, biomass production) based on an ensemble of 18 PTFs applied to four agro-hydrological models, namely: APEX, CANDY, DAISY and SWAP. The models were calibrated for aboveground biomass and phenology of silage maize and evaluated using data of actual evapotranspiration, seepage water and soil water content obtained from a lysimeter facility in Switzerland. ANOVA-based variance partitioning was applied to attribute variance in model outputs to two uncertainty sources (PTF choice, model choice). Overall, we found that agro-hydrological model structural differences had a larger influence on the variance in model outputs than PTF differences. Further analyses undertaken per model showed that the sensitivity of the simulated outputs to the choice of PTF differed between the models; our results showed that the models integrating the Richards equation (SWAP, DAISY) were more sensitive to the choice of PTF than those using a reservoir cascade approach (APEX, CANDY). Our results also showed that simulated outputs using the mean of a PTF ensemble performed better than when using a single PTF, irrespective of the model and output variable. We therefore recommend using PTF ensembles in agro-hydrological modelling studies. The benefit of using large PTF ensembles is, however, likely to be reduced in larger ensembles of agro-hydrological models, as structural model uncertainties will dominate over PTF uncertainties, according to the four-member model ensemble investigated here.</p>","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"76 2","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/ejss.70088","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mineralogical Changes in Acid Sulfate Soils With Thionic Horizons: Insights From the Delta Doce River, Brazil","authors":"Francis Henrique Tenório Firmino,&nbsp;João Carlos Ker,&nbsp;Maurício Paulo Ferreira Fontes,&nbsp;Luiz Felipe Mesquita","doi":"10.1111/ejss.70089","DOIUrl":"https://doi.org/10.1111/ejss.70089","url":null,"abstract":"<p>Acid sulfate soils (ASS) with sulfide minerals (i.e., contain sulfidic materials) are widely distributed in both coastal and inland regions, and if exposed to air, the oxidation of sulfide minerals results in the production of sulfuric acid with the formation of thionic horizons (pH &lt; 4) along with profound mineralogical changes. This study, conducted in the Delta of the Doce River, Espírito Santo, Brazil, investigated the mineralogical transformations of ASS with thionic horizons, focusing on the crystallinity of kaolinites under sulfurization conditions. Soil samples from six profiles with thionic horizons were analysed using X-ray diffraction (XRD), selective extractions and magnetic susceptibility measurements. Mineralogical analysis revealed the predominance of quartz, kaolinite, illite and gibbsite, along with secondary Fe(III) minerals such as jarosite, goethite and hematite, accompanied by a reduction in sulfide content, indicating the advanced stages of sulfide oxidation. In strongly sulfurized soils, an increase in kaolinite crystallinity was observed, suggesting that sulfurization intensifies the destruction of less crystalline phases in the soil. The formation of magnetic minerals was associated with burning processes, highlighting the role of anthropogenic interventions in the mineral transformation of these soils.</p>","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"76 2","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/ejss.70089","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632629","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Erosion Evolution in the Source Regions of the Yangtze and Yellow Rivers From a Climate-Ecology-Hydrology Zoning Perspective","authors":"Wenying Zeng,&nbsp;Qiqi Zhang,&nbsp;Zicheng Yu,&nbsp;Wenyi Sun","doi":"10.1111/ejss.70087","DOIUrl":"https://doi.org/10.1111/ejss.70087","url":null,"abstract":"<div>\u0000 \u0000 <p>Combining soil erosion with comprehensive zoning can reflect the spatial differentiation of soil erosion and reveal the driving forces behind changes in soil erosion. Here, the Köppen climate classification and K-means unsupervised clustering analysis were used to categorise the source regions of the Yangtze and Yellow Rivers (SRYYR) into eight integrated climate-ecology-hydrology zones, considering vegetation, climate, runoff, and sediment transport. The CSLE model was used to analyse soil erosion rate evolution patterns and the impacts of extreme rainfall events in each zone. The study found that the eastern source of the Yangtze River and the northern source of the Yellow River experienced severe erosion. Vegetation and biological practices in the Yellow River source region were significantly better than that of the Yangtze River. Rainfall erosivity increased from northwest to southeast. Extreme rainfall can lead to a 3.86-fold difference in rainfall erosivity, and the annual distribution of rainfall significantly affects soil erosion rates. There were significant spatial differences and trends in soil erosion rates across different regions, with the central part of SRYYR still undergoing significant degradation. Conservation measures resulted in a 26.15% decrease in the B factor (vegetation and biological practice factor) in Zones II, V, VI, and VII, but the current state of vegetation cover in Zone VIII remains a concern (increase 9.23%). The condition of grassland erosion in the SRYYR region improved year by year, while arable land experienced a worsening trend, and the soil erosion rates in forests fluctuated within a certain range. The formation of erosion channels and sediment transport not only changes the landscape but also has profound impacts on water quality and downstream ecosystems.</p>\u0000 </div>","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"76 2","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143602529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a Gas Chromatography–Mass Spectrometry Method for the Determination of Ergosterol in Forest Soils","authors":"Beatriz Albero,&nbsp;Ana García-Valcárcel,&nbsp;Cristina Aponte,&nbsp;Amara Santiesteban-Serrano,&nbsp;Rosa Ana Pérez","doi":"10.1111/ejss.70091","DOIUrl":"https://doi.org/10.1111/ejss.70091","url":null,"abstract":"<div>\u0000 \u0000 <p>Ergosterol is a sterol compound present in fungal cell membranes and is used as a biomarker to measure fungal biomass. Therefore, an accurate analytical method is essential to quantify the presence of ergosterol in any soil type, regardless of its physicochemical characteristics or environmental conditions. The main objective of our study was to optimise and validate an analytical method for the assessment of total ergosterol content in soil. Different parameters were evaluated during the optimisation of the method to extract ergosterol from agricultural and forest soils. The accuracy of the method was evaluated by the recovery of ergosterol from soil spiked at two levels, resulting in good recoveries for both types of soil. Gas chromatography–mass spectrometry was used to analyse soil extracts without requiring a derivatization step. This simplifies the procedure and avoids the use of toxic reagents. The analytical method was applied to determine ergosterol in forest soils taken at two depths (0–5 cm and 5–10 cm). Significant differences in the concentrations of ergosterol in the top and deeper layers of soil were observed. The quantity of ergosterol in the upper soil layer ranged from 3.0 to 29.9 mg/kg dry weight, whereas in the deeper layer of soil, it ranged from 0.5 to 4.8 mg/kg dry weight. The principal component analysis performed between ergosterol concentration and soil characteristics at both depths displayed a correlation between ergosterol and organic matter.</p>\u0000 </div>","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"76 2","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143595360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"FT-MIR Spectroscopic Analysis of the Organic Carbon Fractions in Australian Mineral Soils","authors":"Lewis Walden,&nbsp;Farid Sepanta,&nbsp;R. A. Viscarra Rossel","doi":"10.1111/ejss.70084","DOIUrl":"https://doi.org/10.1111/ejss.70084","url":null,"abstract":"<p>Soil organic carbon (C) is heterogeneous. It exists in various forms along a decomposition continuum, from labile fast-cycling compounds to more persistent forms that can reside in the soil for centuries to millennia. The soil organic C fractionation methods account for this complexity by separating soil organic C into distinct groups with similar turnover. Here, we aimed to (a) fractionate 401 mineral soils from three depths (0–10, 10–20, 20–30 cm) with small organic C concentrations (&lt; 2.5% mean C) and varying textures and mineralogy using a granulometric method to derive the particulate organic C in macroaggregates (POC_mac), the particulate organic C in microaggregates (POC_mic) and the mineral-associated organic carbon (MAOC), (b) test whether mid-infrared (MIR) spectra (4000–450 cm⁻¹) can discriminate the C fractions and characterise their distinct organic and mineral functional groups and (c) examine which mineral and organic functional groups concomitantly occur in the spectra of the C fractions to provide insights into their composition. A canonical variate analysis showed that the MIR spectra use information from mineral and organic absorptions to discriminate the organic C fractions. Closer investigation of specific regions of the MIR spectrum showed, as might be expected, that absorptions relating to quartz were more pronounced in the POC_mac and POC_mic fractions, and clay mineral absorptions were dominant in the MAOC fraction. The stretching vibrations of alkyl CH₂ bonds (2930, 2860 cm⁻¹) were the most prominent organic absorptions, particularly in the MAOC fraction, followed by absorptions from amide groups (1525, 1630 cm⁻¹). Our findings demonstrate that MIR spectroscopy can characterise the compositional differences between the organic C fractions and identify co-occurrences of organic functional groups, such as alkyl CH₂, with clay minerals. They suggest associations between organic molecules and clay minerals that contribute to soil organic C persistence. Future research and applications should combine fractionation with MIR spectroscopy to enhance the resolution of soil C analyses and the reliability of fractionations.</p>","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"76 2","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/ejss.70084","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143595146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How to Refocus Soil Research When Reacting to the Strategic Dialogue on the Future of EU Agriculture","authors":"Johan Bouma","doi":"10.1111/ejss.70085","DOIUrl":"https://doi.org/10.1111/ejss.70085","url":null,"abstract":"<div>\u0000 \u0000 <p>The recent strategic policy dialogue on the future of agriculture in the European Union focuses on sustainable development and presents a clear challenge to the research community, including soil science. Framing sustainability in the context of the UN Sustainable Development Goals (SDGs), a recent case study is reviewed in this Opinion paper showing that techniques are available to assess ecosystem services with indicators and thresholds in line with some key SDGs and the EU dialogue. Also, soil health, which partly defines SDG 15 and has a major impact on several other ecosystem services, can be characterised with traditional and innovative methods. However, research on soil-specific thresholds needs more attention in future research. The tendency in science to develop new technologies and insights is crucial to scientific progress but may inhibit the application of available technology that is urgently needed to meet the present sustainability challenge. Specific case studies on the role of soils contributing to ecosystem services in line with the production of healthy food, maintaining the quality of ground and surface water, climate mitigation and preservation of biodiversity are needed to better demonstrate crucial contributions of soil science in an interdisciplinary context. The case study showed that field research is still needed to check assumptions being made when applying certain methods or simulation models. Living Labs and Lighthouses are ideal vehicles to allow true interaction between farmers and researchers, while Lighthouses will allow stimulating exchanges among farmers. If farmers do not embrace innovative methodologies to achieve sustainable development, all reports and dialogues will remain fruitless.</p>\u0000 </div>","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"76 2","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143581634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Elevation and Mineralogy on the Amount and Turnover of Fractionated Organic Carbon in Paddy Soils in Nepal","authors":"Atsuhito Suzuki,&nbsp;Junta Yanai,&nbsp;Prakash Paneru,&nbsp;Shree Prasad Vista,&nbsp;Rota Wagai,&nbsp;Sota Tanaka,&nbsp;Hirotsugu Arai,&nbsp;Ichiro Tayasu,&nbsp;Atsushi Nakao","doi":"10.1111/ejss.70073","DOIUrl":"https://doi.org/10.1111/ejss.70073","url":null,"abstract":"<div>\u0000 \u0000 <p>The storage of soil organic matter (SOM) is essential for maintaining and improving soil fertility. To obtain basic information about the status of SOM in paddy fields in Nepal under various ecological settings, we investigated the amount and turnover rate of stored carbon (C) in fractionated SOM in the surface layer. Soil samples from the top 15 cm plough layer were collected from 21 sites along an elevation gradient ranging from 78 to 2002 m a.s.l. in the central region of the country, and in eight sites in the lowland area in the eastern region to investigate regional differences in SOM status. SOM was fractionated into four components: (1) light fraction (LF, &lt; 1.8 g cm⁻³), (2) heavy fraction (HF) consisting of physically stable aggregates, (3) oxidizable clay + silt fraction (OxF), and (4) nonoxidizable clay + silt fraction (NOxF) forming organo-mineral complexes with fine-textured minerals. The amounts of C in all fractions were determined, and the ∆¹⁴C values of selected samples were evaluated as indices of C turnover rate. The amount of stored C increased with elevation from 78 m (13.3 g kg⁻¹) to <i>ca.</i> 1700 m a.s.l. (28.0 g kg⁻¹). However, the total C content and C contents in LF, OxF, and NOxF exhibited decreasing trends from 1700 to <i>ca.</i> 2000 m a.s.l. (20.4 g kg⁻¹), probably because of decreased biomass production and decreased amorphous soil minerals at <i>ca</i>. 2000 m. The Δ¹⁴C values indicated that the C turnover rates in HF, OxF, and NOxF were faster at higher elevations (1221 m) than at lower elevations (78 m). These results suggest that mineralogy can have greater influence on C turnover than the climate difference in these mineral-associated C fractions through SOM stabilisation. In lowland, the amounts and turnover rates of stored C in the soil fractions were larger and slower in the central region than in the eastern region, respectively, reflecting differences in soil texture and mineralogy. Multiple regression analysis showed that the amount of C was negatively influenced by the mean annual temperature in all fractions and positively influenced by amorphous Al minerals (Alo–Alp) in OxF and NOxF. The coefficients for temperature further suggest that the relative vulnerability of C to temperature increase is in the order of LF&gt;HF&gt;OxF&gt;NOxF. These findings can serve as a basis for the maintenance and improvement of paddy soil fertility in Nepal for sustainable agricultural management.</p>\u0000 </div>","PeriodicalId":12043,"journal":{"name":"European Journal of Soil Science","volume":"76 2","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143530416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}