Soil最新文献

{"title":"Portable X-Ray Fluorescence as a Tool for Urban Soil Contamination Analysis: Accuracy, Precision, and Practicality","authors":"Eriell Jenkins, John Galbraith, Anna Paltseva","doi":"10.5194/egusphere-2024-3101","DOIUrl":"https://doi.org/10.5194/egusphere-2024-3101","url":null,"abstract":"<strong>Abstract.</strong> Urban agriculture has become an essential component of urban sustainability, but it often faces the challenge of soil contamination with heavy metal(loid)s like lead (Pb), arsenic (As), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), and zinc (Zn). Traditional laboratory methods for detecting these contaminants, such as atomic absorption spectroscopy (AAS) and inductively coupled plasma techniques (ICP-MS, ICP-OES, ICP-AES), are accurate but can be costly, time-consuming, and require extensive sample preparation. Portable X-ray fluorescence (PXRF) presents a promising alternative, offering rapid, in situ analysis with minimal sample preparation. The study reviews literature on PXRF analyzers to determine their accuracy and precision in analyzing heavy metal(loid)s in urban soils, with the goal of optimizing sampling, reducing laboratory costs and time, and identifying priority metal contamination hotspots. A literature review was conducted using Web of Science and Google Scholar, focusing on studies that validated PXRF measurements with alternate laboratory methods or certified reference materials (CRMs). This study reviews 67 publications to evaluate the accuracy and precision of PXRF in analyzing heavy metal(loid)s in urban soils. The review covers instrument types, calibration methods, testing conditions, and sample preparation techniques. Results show that, when properly calibrated, particularly with CRMs, PXRF achieves reliable accuracy. <em>Ex situ</em> measurements tend to be more precise due to controlled conditions, although <em>in situ</em> measurements offer practical advantages in urban settings. Portable XRF emerges as a viable method for assessing urban soil contamination, balancing accuracy and practicality. Future research should focus on optimizing sample preparation and calibration to further enhance PXRF reliability in urban environments. This review highlights PXRF’s potential to streamline soil testing, reduce costs, and identify contamination hotspots, contributing to safer urban agriculture and more precise soil survey and conservation efforts.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"57 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142678347","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 interactions along the elevation gradient of the James Ross Island (Antarctica)","authors":"Vítězslav Vlček, David Juřička, Martin Valtera, Helena Dvořáčková, Vojtěch Štulc, Michaela Bednaříková, Jana Šimečková, Peter Váczi, Miroslav Pohanka, Pavel Kapler, Miloš Barták, Vojtěch Enev","doi":"10.5194/soil-10-813-2024","DOIUrl":"https://doi.org/10.5194/soil-10-813-2024","url":null,"abstract":"Abstract. Around half of the Earth's soil organic carbon (SOC) is presently stored in the Northern Hemisphere permafrost region. In polar permafrost regions, low temperatures particularly inhibit both the production and biodegradation of organic matter. Under such conditions, abiotic factors such as mesoclimate, pedogenic substrate or altitude are thought to be more important for soil development than biological factors. In Antarctica, biological factors are generally underestimated in soil development due to the rare occurrence of higher plants and the short time since deglaciation. In this study, we aim to assess the relationship between SOC and other soil properties related to the pedogenic factors or properties. Nine plots were investigated along the altitudinal gradient from 10 to 320 m in the deglaciated area of James Ross Island (Ulu Peninsula) using a parallel tea-bag decomposition experiment. SOC contents showed a positive correlation with the content of easily extractable glomalin-related soil protein (EE-GRSP; Spearman r=0.733, P=0.031) and the soil buffering capacity (expressed as ΔpH; Spearman r=0.817, P=0.011). The soil-available P was negatively correlated with altitude (Spearman r=-0.711, P=0.032), and the exchangeable Mg was negatively correlated with the rock fragment content (Spearman r=-0.683, P=0.050). No correlation was found between the available mineral nutrients (P, K, Ca and Mg) and SOC or GRSP. This may be a consequence of the inhibition of biologically mediated nutrient cycling in the soil. Therefore, the main factor influencing nutrient availability in these soils does not seem to the biotic environment; rather, the main impact appears to stem from the abiotic environment influencing the mesoclimate (altitude) or the level of weathering (rock content). Incubation in tea bags for 45 d resulted in the consumption and translocation of more labile polyphenolic and water-extractable organic matter, along with changes in the C content (increase of up to +0.53 % or decrease of up to −1.31 % C) and a decrease in the C:N ratio (from 12.5 to 7.1–10.2), probably due to microbial respiration and an increase in the abundance of nitrogen-binding microorganisms. Our findings suggest that one of the main variables influencing the SOC/GRSP content is not the altitude or coarse-fraction content (for which a correlation with SOC/GRSP was not found); rather, we suspect effects from other factors that are difficult to quantify, such as the availability of liquid water.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"7 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142670793","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":"Investigating the complementarity of thermal and physical soil organic carbon fractions","authors":"Amicie A. Delahaie, Lauric Cécillon, Marija Stojanova, Samuel Abiven, Pierre Arbelet, Dominique Arrouays, François Baudin, Antonio Bispo, Line Boulonne, Claire Chenu, Jussi Heinonsalo, Claudy Jolivet, Kristiina Karhu, Manuel Martin, Lorenza Pacini, Christopher Poeplau, Céline Ratié, Pierre Roudier, Nicolas P. A. Saby, Florence Savignac, Pierre Barré","doi":"10.5194/soil-10-795-2024","DOIUrl":"https://doi.org/10.5194/soil-10-795-2024","url":null,"abstract":"Abstract. Partitioning soil organic carbon (SOC) in fractions with different biogeochemical stability is useful to better understand and predict SOC dynamics and provide information related to soil health. Multiple SOC partition schemes exist, but few of them can be implemented on large sample sets and therefore be considered relevant options for soil monitoring. The well-established particulate organic carbon (POC) vs. mineral-associated organic carbon (MAOC) physical fractionation scheme is one of them. Introduced more recently, Rock-Eval® thermal analysis coupled with the PARTYSOC machine learning model can also fractionate SOC into active (Ca) and stable SOC (Cs). A debate is emerging as to which of these methods should be recommended for soil monitoring. To investigate the complementarity or redundancy of these two fractionation schemes, we compared the quantity and environmental drivers of SOC fractions obtained on an unprecedented dataset from mainland France. About 2000 topsoil samples were recovered all over the country, presenting contrasting land cover and pedoclimatic characteristics, and analysed. We found that the environmental drivers of the fractions were clearly different, the more stable MAOC and Cs fractions being mainly driven by soil characteristics, whereas land cover and climate had a greater influence on more labile POC and Ca fractions. The stable and labile SOC fractions provided by the two methods strongly differed in quantity (MAOC/Cs=1.88 ± 0.46 and POC/Ca=0.36 ± 0.17; n=843) and drivers, suggesting that they correspond to fractions with different biogeochemical stability. We argue that, at this stage, both methods can be seen as complementary and potentially relevant for soil monitoring. As future developments, we recommend comparing how they relate to indicators of soil health such as nutrient availability or soil structural stability and how their measurements can improve the accuracy of SOC dynamics models.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"4 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142599213","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":"Overcoming barriers in long-term, continuous monitoring of soil CO2 flux: A low-cost sensor system","authors":"Thi Thuc Nguyen, Nadav Bekin, Ariel Altman, Martin Maier, Nurit Agam, Elad Levintal","doi":"10.5194/egusphere-2024-3156","DOIUrl":"https://doi.org/10.5194/egusphere-2024-3156","url":null,"abstract":"<strong>Abstract.</strong> Soil CO₂ flux (<em>F_s</em>) is a carbon cycling metric crucial for assessing ecosystem carbon budgets and global warming. However, global <em>F_s</em> datasets often suffer from low temporal-spatial resolution, as well as from spatial bias. <em>F_s</em> observations are severely deficient in tundra and dryland ecosystems due to financial and logistical constraints of current methods for <em>F_s</em> quantification. In this study, we introduce a novel, low-cost sensor system (LC-SS) for long-term, continuous monitoring of soil CO₂ concentration and flux. The LC-SS, built from affordable, open-source hardware and software, offers a cost-effective solution (~USD700), accessible to low-budget users, and opens the scope for research with a large number of sensor system replications. The LC-SS was tested over ~6 months in arid soil conditions, where fluxes are small, and accuracy is critical. CO₂ concentration and soil temperature were measured at 10-min intervals at depths of 5 and 10 cm. The LC-SS demonstrated high stability and minimal maintenance requirements during the tested period. Both diurnal and seasonal soil CO₂ concentration variabilities were observed, highlighting the system's capability of continuous, long-term, in-situ monitoring of soil CO₂ concentration. In addition, <em>F_s</em> was calculated using the measured CO₂ concentration via the gradient method and validated with <em>F_s</em> measured by the flux chamber method using the well-accepted LI-COR gas analyzer system. Gradient method <em>F_s</em>was in good agreement with flux chamber <em>F_s</em>, highlighting the potential for alternative or concurrent use of the LC-SS with current methods for <em>F_s</em> estimation. Leveraging the accuracy and cost-effectiveness of the LC-SS (below 10 % of automated gas analyzer system cost), strategic implementation of LC-SSs could be a promising means to effectively increase the number of measurements, spatially and temporally, ultimately aiding in bridging the gap between global <em>F_s</em> uncertainties and current measurement limitations.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"25 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142594754","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":"Exploring the link between cation exchange capacity and magnetic susceptibility","authors":"Gaston Matias Mendoza Veirana, Hana Grison, Jeroen Verhegge, Wim Cornelis, Philippe De Smedt","doi":"10.5194/egusphere-2024-3306","DOIUrl":"https://doi.org/10.5194/egusphere-2024-3306","url":null,"abstract":"<strong>Abstract.</strong> This study explores the relationship between soil magnetic susceptibility (𝜅) and cation exchange capacity (𝐶𝐸𝐶) across diverse European soils, aiming to enhance pedotransfer functions (PTFs) for soil 𝐶𝐸𝐶 using near-surface electromagnetic geophysics. We hypothesize that soil 𝜅, can improve the prediction of 𝐶𝐸𝐶 by reflecting the soil’s mineralogical composition, particularly in sandy soils. We collected data from 49 soil samples in vertical profiles across Belgium, the Netherlands, and Serbia, including 𝜅 in field conditions (𝜅^∗), low and high frequency 𝜅 in the laboratory, in-site electrical conductivity (𝜎), iron content, soil texture, humus content, bulk density, water content, water pH, and 𝐶𝐸𝐶. We used these properties as features to develop univariable and multivariable (in pairs) polynomial regressions to predict 𝐶𝐸𝐶 for sandy and clayey soils. Results indicate that 𝜅^∗ significantly improves 𝐶𝐸𝐶 predictions in sandy soils, independent of clay content, with a combined 𝜅^∗- 𝜎 model achieving the highest predictive performance (<em>R</em>² = 0.94). In contrast, laboratory-measured 𝜅 was less effective, likely due to sample disturbance. This study presents a novel 𝐶𝐸𝐶 PTF based on 𝜎 and 𝜅^∗, offering a rapid, cost-effective method for estimating 𝐶𝐸𝐶 in field conditions. While our findings underscore the value of integrating geophysical measurements into soil characterization, further research is needed to refine the 𝜅- 𝐶𝐸𝐶 relationship and develop a more widely applicable model.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"36 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142580520","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":"Moderate N fertilizer reduction with straw return modulates cropland functions and microbial traits in a meadow soil","authors":"Yan Duan, Minghui Cao, Wenling Zhong, Yuming Wang, Zheng Ni, Mengxia Zhang, Jiangye Li, Yumei Li, Xianghai Meng, Lifang Wu","doi":"10.5194/soil-10-779-2024","DOIUrl":"https://doi.org/10.5194/soil-10-779-2024","url":null,"abstract":"Abstract. Nitrogen (N) fertilization has received worldwide attention due to its benefits with regard to soil fertility and productivity, but excess N application also causes an array of ecosystem degenerations, such as greenhouse gas emissions. Generally, soil microorganisms are considered to be involved in upholding a variety of soil functions. However, the linkages between soil cropland properties and microbial traits under different N fertilizer application rates remain uncertain. To address this, a 4-year in situ field experiment was conducted in a meadow soil from the Northeast China Plain after straw return with the following treatments combined with regular phosphorus (P) and potassium (K) fertilization: (i) regular N fertilizer (N + PK), (ii) 25 % N fertilizer reduction (0.75N + PK), (iii) 50 % N fertilizer reduction (0.5N + PK), and (IV) no N fertilizer (PK). Cropland properties and microbial traits responded distinctly to the different N fertilizer rates. Treatment 0.75N + PK had overall positive effects on soil fertility, productivity, straw decomposition, and microbial abundance and functioning and alleviated greenhouse effects. Specifically, no significant difference was observed in soil organic carbon (SOC), total N, P content, straw C, N release amounts, microbial biomass C, N content, and cellulase and N-acetyl-D-glucosaminidase activities, which were all significantly higher than in 0.5N + PK and PK. Greenhouse gas emissions was reduced with the decreasing N input levels. Moreover, the highest straw biomass and yield were measured in 0.75N + PK, which were significantly higher than in 0.5N + PK and PK. Meanwhile, 0.75N + PK up-regulated aboveground biomass and soil C:N and thus increased the abundance of genes encoding cellulose-degrading enzymes, which may imply the potential ability of C and N turnover. In addition, most observed changes in cropland properties were strongly associated with microbial modules and keystone taxa. The Lasiosphaeriaceae within the module-1 community showed significant positive correlations with straw degradation rate and C and N release, while the Terrimonas within the module-3 community showed a significant positive correlation with production, which was conducive to soil multifunctionality. Therefore, our results suggest that straw return with 25 % chemical N fertilizer reduction is optimal for achieving soil functions. This study highlights the importance of abiotic and biotic factors in soil health and supports green agricultural development by optimizing N fertilizer rates in meadow soil after straw return.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"17 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142580554","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":"Advancing studies on global biocrust distribution","authors":"Siqing Wang, Li Ma, Liping Yang, Yali Ma, Yafeng Zhang, Changming Zhao, Ning Chen","doi":"10.5194/soil-10-763-2024","DOIUrl":"https://doi.org/10.5194/soil-10-763-2024","url":null,"abstract":"Abstract. Biological soil crusts (biocrusts hereafter) cover a substantial proportion of the dryland ecosystem and play crucial roles in ecological processes such as biogeochemical cycles, water distribution, and soil erosion. Consequently, studying the spatial distribution of biocrusts holds great significance for drylands, especially on a global scale, but it remains limited. This study aimed to simulate global-scale investigations of biocrust distribution by introducing three major approaches, namely spectral characterization indices, dynamic vegetation models, and geospatial models, while discussing their applicability. We then summarized the present understanding of the factors influencing biocrust distribution. Finally, to further advance this field, we proposed several potential research topics and directions, including the development of a standardized biocrust database, enhancement of non-vascular vegetation dynamic models, integration of multi-sensor monitoring, extensive use of machine learning, and a focus on regional research co-development. This work will significantly contribute to mapping the biocrust distribution and thereby advance our understanding of dryland ecosystem management and restoration.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"30 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142488346","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":"Pooled Error Variance and Covariance Estimation of Sparse In Situ Soil Moisture Sensor Measurements in Agricultural Fields in Flanders","authors":"Marit G. A. Hendrickx, Jan Vanderborght, Pieter Janssens, Sander Bombeke, Evi Matthyssen, Anne Waverijn, Jan Diels","doi":"10.5194/egusphere-2024-2943","DOIUrl":"https://doi.org/10.5194/egusphere-2024-2943","url":null,"abstract":"<strong>Abstract.</strong> Accurately quantifying errors in soil moisture measurements from in situ sensors at fixed locations is essential for reliable state and parameter estimation in probabilistic soil hydrological modeling. This quantification becomes particularly challenging when the number of sensors per field or measurement zone (MZ) is limited. When direct calculation of errors from sensor data in a certain MZ is not feasible, we propose to pool systematic and random errors of soil moisture measurements for a specific measurement setup to derive a pooled error covariance matrix that applies across different fields and soil types. In this study, a pooled error covariance matrix was derived from soil moisture sensor measurements and soil moisture sampling campaigns conducted over three growing seasons, covering 93 cropping cycles in agricultural fields with diverse soil textures in Belgium. The MZ soil moisture estimated from soil samples, which showed a small standard error (<span>0.0038 </span>m³ m^‑3) and which was not correlated between different sampling campaigns since soil samples were taken at different locations, represented the ‘true’ MZ soil moisture. First, we established a pooled linear recalibration of the TEROS 10 (Meter Group, Inc., USA) manufacturer's sensor calibration function. Then, for each individual sensor as well as for each MZ, we identified systematic deviations and temporally varying residual deviations between the calibrated sensor data and sampling data. The autocovariance of the individual or the MZ-averaged sensor measurement errors was represented by the variance of the systematic deviations across all sensors or MZs whereas the random error variance was calculated from the variance of the pooled residual deviations. The total error variance was equal to the sum of the autocovariance and random error variance. Due to spatial sensor correlation, the variance and autocovariance of MZ-average sensor measurement errors could not be derived from the individual sensor error variances and covariances. The pooled error covariance matrix of the MZ-averaged soil moisture measurements indicated a significant sensor error autocorrelation of 0.518, as the systematic error standard deviation (σ_α- = 0.0327 m³ m^‑3) was similar to the random error standard deviation (σ_ε- = 0.0316 m³ m^‑3). These results demonstrate that the common assumption of uncorrelated random errors to determine parameter and model prediction uncertainty is not valid when measurements from sparse in situ soil moisture sensors are used to parameterize soil hydraulic models. Further research is required to assess to what extent the error covariances found in this study can be transferred to other areas, and how they impact parameter estimation in soil hydrological modeling.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"22 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142486702","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":"Managing Soil Nitrogen Surplus: The Role of Winter Cover Crops in N2O Emissions and Carbon Sequestration","authors":"Victoria Nasser, René Dechow, Mirjam Helfrich, Ana Meijide, Pauline Sophie Rummel, Heinz-Josef Koch, Reiner Ruser, Lisa Essich, Klaus Dittert","doi":"10.5194/egusphere-2024-2849","DOIUrl":"https://doi.org/10.5194/egusphere-2024-2849","url":null,"abstract":"<strong>Abstract.</strong> Cover crops are acclaimed for enhancing the environmental sustainability of agricultural practices by aiding in carbon (C) sequestration and reducing losses of soil mineral nitrogen (SMN) after harvest. Yet, their influence on nitrous oxide (N₂O) emissions—a potent greenhouse gas—presents a complex challenge, with findings varying across different studies. This research aimed to elucidate the effects of various winter cover crops—winter rye (frost-tolerant), saia oat (frost-sensitive grass), and spring vetch (frost-sensitive legume)—against a control of bare fallow on SMN dynamics, N₂O emissions and C sequestration. While cover crops efficiently lowered SMN levels during their growth, they also increased N₂O emissions in comparison to bare fallow conditions. Notably, winter frost events triggered significant emissions from the frost-sensitive varieties. Moreover, the practices of residue incorporation and soil cultivation were associated with increased N₂O emissions across all cover crop treatments. Winter rye, distinguished by its high biomass production and nitrogen (N) uptake, was linked to the highest cumulative N₂O emissions, highlighting the impact of biomass management and cultivation techniques on N cycling and N₂O emissions. Cover crop treatment lead to a slight increase in direct N₂O emissions (4.5±3.0, 2.7±1.4, and 3.1±3.8 kg N₂O-N ha^-1 for rye, oat, and vetch, respectively) compared to the fallow (2.6±1.7 kg N₂O-N ha^-1) over the entire trial period (16 months). However, the potential of non-legume cover crops to reduce indirect N₂O emissions compared to fallow (0.3±0.4 and 0.2±0.1 kg N₂O-N ha^-1 a^-1 for rye and oat respectively) and their contribution to carbon sequestration (120–150 kg C ha^-1 a^-1 over a period of 50 years when growing cover crops every fourth year) might partially counterbalance these emissions. Thus, while cover crops offer environmental benefits, their net impact on N₂O emissions necessitates further exploration into optimized cover crop selection and management strategies tailored to specific site conditions to fully leverage their ecological advantages.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"73 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142444012","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":"The impact of agriculture on tropical mountain soils in the western Peruvian Andes: a pedo-geoarchaeological study of terrace agricultural systems in the Laramate region (14.5° S)","authors":"Fernando Leceta, Christoph Binder, Christian Mader, Bertil Mächtle, Erik Marsh, Laura Dietrich, Markus Reindel, Bernhard Eitel, Julia Meister","doi":"10.5194/soil-10-727-2024","DOIUrl":"https://doi.org/10.5194/soil-10-727-2024","url":null,"abstract":"Abstract. This integrated pedo-geoarchaeological study focuses on three abandoned pre-Hispanic terrace agricultural systems near Laramate in the southern Andes of Peru (14.5° S), aiming to unravel the pedological and land-use history of the region, which served as a significant agricultural hub during pre-Hispanic times. The key objectives of the investigation involved contextualizing the former agricultural management system within its geomorphological and palaeoecological framework and assessing the impact of agricultural practices on soil development and quality by comparing non-irrigated agricultural terrace soils with their undisturbed palaeo-pedological counterparts. The Laramate terrace complex, with its diverse terrace systems and varied geomorphological and geological settings, provided an ideal setting for the investigation. This comprehensive examination integrated a range of methodologies, including field surveys, digital mapping, and geomorphological analysis based on GIS and remote sensing applications, soil analysis (e.g. grain size, bulk chemistry, nutrient budget), plant microfossils (phytoliths and starch), and radiocarbon dating. In the Laramate region, the geomorphological setting of terrace agricultural systems promotes their optimal functioning. The terraces are often located in sun-sheltered areas with western exposure on middle and lower slopes or valley bottoms, which mitigate intense solar radiation, reduce evapotranspiration, increase soil moisture, and minimize erosion. The study identifies three soil groups in the Laramate region: Phaeozems, Andosols, and Anthrosols. Unique characteristics of Phaeozems challenge typical descriptions, influenced by factors such as climatic seasonality, vegetation, fauna, lithology, and aeolian inputs. The terrace soils in the Laramate region are classified as Terric Anthrosols, showing no significant degradation even after long-term use. Their balanced acidity and nutrient levels support Andean crop cultivation. Traditional non-mechanized tools, such as the chaquitaclla and rucana, likely minimized soil disruption. The terrace tillage horizons have high organic matter, indicating intentional organic manuring. Phytolith concentrations suggest intensive agricultural activity, particularly maize cultivation, with varying patterns suggesting changes in cultivation, fertilization, or mulching practices over time. Starch grain identification aligns with phytolith analyses, reinforcing maize's significance in the region. Although the use of animal-origin fertilizers requires further investigation, there is no evidence of nutrient maintenance through seasonal burning. Irrigation was minimal, and the abandonment of the pre-Hispanic cultivation system was unlikely due to soil exhaustion or terrace instability. Overall, the pre-Hispanic history of terrace agriculture in the Laramate region extends over four development phases, reflecting dynamic interactions between environmental, cultural, and a","PeriodicalId":48610,"journal":{"name":"Soil","volume":"1 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142431321","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}