Pub Date : 2025-05-13DOI: 10.5194/egusphere-2025-1966
Dave O'Leary, Patrick Tuohy, Owen Fenton, Mark G. Healy, Hilary Pierce, Asaf Shnel, Eve Daly
Abstract. Open drainage ditch (i.e. open drain) damming aims to raise the water table in agricultural grassland peat soils thereby reducing greenhouse gas (GHG) emissions. A current knowledge gap is how to examine the spatial and temporal effectiveness of such an action i.e., assessing the behaviour of the water table in the adjoining field. To address this gap, at a drained agricultural grassland site with shallow fen peat soils (ranging from 0 to 2 m depth), water level in an open drain was raised by installing a dam. Associated changes to the water table depth (WTD) were monitored using two nests of dip wells installed at two locations (Rewetted and Normal areas) in the adjoining field. Soil profile volumetric water content (VWC) data were obtained in these two areas in addition to the temperature, salinity, pH, and electrical conductivity signature of the water in the open drain. These data were integrated with geophysical (electromagnetic induction (EMI)) survey data conducted during summer and winter. Results from the dip wells (located > 20 m from dam) indicated that no measurable change in WTD occurred due to the dam installation, aligning with previous studies suggesting limited spatial influence in agricultural fen peat soils. VWC profiles, while consistent with peat physical properties, showed no deviation attributable to drain damming. The EMI results identified a distinct zone with electrical conductivity values similar to those of open drain water, suggesting localised water infiltration within ~20 m of the dammed drain during summer. This spatial impact was less evident during winter, likely due to increased precipitation and regional groundwater influence. This study demonstrates that EMI surveys, shown here in combination with other high-resolution data capture, can detect rewetting effects when combined with neural network clustering and Multi-Cluster Average Standard Deviation analysis, highlighting its value for rapid site assessment. Moreover, the results underscore the importance of survey timing, as summer measurements provided clearer evidence of drain damming impact than winter measurements.
{"title":"Assessing the impact of rewetting agricultural fen peat soil via open drain damming: an agrogeophysical approach","authors":"Dave O'Leary, Patrick Tuohy, Owen Fenton, Mark G. Healy, Hilary Pierce, Asaf Shnel, Eve Daly","doi":"10.5194/egusphere-2025-1966","DOIUrl":"https://doi.org/10.5194/egusphere-2025-1966","url":null,"abstract":"<strong>Abstract.</strong> Open drainage ditch (i.e. open drain) damming aims to raise the water table in agricultural grassland peat soils thereby reducing greenhouse gas (GHG) emissions. A current knowledge gap is how to examine the spatial and temporal effectiveness of such an action i.e., assessing the behaviour of the water table in the adjoining field. To address this gap, at a drained agricultural grassland site with shallow fen peat soils (ranging from 0 to 2 m depth), water level in an open drain was raised by installing a dam. Associated changes to the water table depth (WTD) were monitored using two nests of dip wells installed at two locations (Rewetted and Normal areas) in the adjoining field. Soil profile volumetric water content (VWC) data were obtained in these two areas in addition to the temperature, salinity, pH, and electrical conductivity signature of the water in the open drain. These data were integrated with geophysical (electromagnetic induction (EMI)) survey data conducted during summer and winter. Results from the dip wells (located > 20 m from dam) indicated that no measurable change in WTD occurred due to the dam installation, aligning with previous studies suggesting limited spatial influence in agricultural fen peat soils. VWC profiles, while consistent with peat physical properties, showed no deviation attributable to drain damming. The EMI results identified a distinct zone with electrical conductivity values similar to those of open drain water, suggesting localised water infiltration within ~20 m of the dammed drain during summer. This spatial impact was less evident during winter, likely due to increased precipitation and regional groundwater influence. This study demonstrates that EMI surveys, shown here in combination with other high-resolution data capture, can detect rewetting effects when combined with neural network clustering and Multi-Cluster Average Standard Deviation analysis, highlighting its value for rapid site assessment. Moreover, the results underscore the importance of survey timing, as summer measurements provided clearer evidence of drain damming impact than winter measurements.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"3 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143940389","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}
Pub Date : 2025-05-05DOI: 10.5194/soil-11-363-2025
Sajjad Raza, Hannah V. Cooper, Nicholas T. Girkin, Matthew S. Kent, Malcolm J. Bennett, Sacha J. Mooney, Tino Colombi
Abstract. Plant processes regulating the quantity and quality of soil organic carbon inputs such as photosynthesis, above- and below-ground plant growth, and root exudation are integral to our understanding of soil carbon dynamics. However, based on a bibliometric analysis including more than 55 000 scientific papers, we found that plant physiology has been severely underrepresented in global soil organic carbon research. Less than 10 % of peer-reviewed soil organic carbon research published in the last century addressed plant physiological processes relevant to soil carbon inputs. Similarly, plant physiology was overlooked by the overwhelming majority (>90 %) of the peer-reviewed literature investigating linkages between soil organic carbon, climate change, and land use and land management. These findings show that our understanding of both soil carbon dynamics and the carbon sequestration potential of terrestrial ecosystems is largely built on research that neglects the fundamental processes underlying organic carbon inputs. We maintain that the active engagement of plant scientists in soil carbon research is imperative for shedding light on this blind spot. Long-term interdisciplinary research will be essential for developing a comprehensive perspective of soil carbon dynamics and informing and designing effective policies that support soil carbon sequestration.
{"title":"Missing the input: the underrepresentation of plant physiology in global soil carbon research","authors":"Sajjad Raza, Hannah V. Cooper, Nicholas T. Girkin, Matthew S. Kent, Malcolm J. Bennett, Sacha J. Mooney, Tino Colombi","doi":"10.5194/soil-11-363-2025","DOIUrl":"https://doi.org/10.5194/soil-11-363-2025","url":null,"abstract":"Abstract. Plant processes regulating the quantity and quality of soil organic carbon inputs such as photosynthesis, above- and below-ground plant growth, and root exudation are integral to our understanding of soil carbon dynamics. However, based on a bibliometric analysis including more than 55 000 scientific papers, we found that plant physiology has been severely underrepresented in global soil organic carbon research. Less than 10 % of peer-reviewed soil organic carbon research published in the last century addressed plant physiological processes relevant to soil carbon inputs. Similarly, plant physiology was overlooked by the overwhelming majority (>90 %) of the peer-reviewed literature investigating linkages between soil organic carbon, climate change, and land use and land management. These findings show that our understanding of both soil carbon dynamics and the carbon sequestration potential of terrestrial ecosystems is largely built on research that neglects the fundamental processes underlying organic carbon inputs. We maintain that the active engagement of plant scientists in soil carbon research is imperative for shedding light on this blind spot. Long-term interdisciplinary research will be essential for developing a comprehensive perspective of soil carbon dynamics and informing and designing effective policies that support soil carbon sequestration.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"9 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143910662","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}
Pub Date : 2025-04-29DOI: 10.5194/egusphere-2025-1546
Dario Püntener, Tatjana Carina Speckert, Yves-Alain Brügger, Guido Lars Bruno Wiesenberg
Abstract. Soil organic matter (SOM) decomposition in alpine environments is influenced by multiple factors including temperature and substrate quality. As climate change will have an impact on both factors, it is essential to improve our knowledge, how, e.g., warming will modify carbon cycling in these environments to better prepare soil management for future conditions, even in alpine regions. This study investigates how warming and organic inputs affect SOM decomposition in alpine forest and pasture soils through a one-year laboratory incubation experiment. Soils were exposed to three temperatures (12.5 °C, 16.5 °C and 20.5 °C), with and without the addition of fresh grass litter. While higher temperatures accelerated decomposition, the availability of fresh organic matter played a more decisive role, especially in the lignin-rich forest soil. Without fresh litter, SOM decomposition was limited, suggesting that substrate availability in combination with temperature increase plays a greater role in microbial activity than temperature alone. The forest soil exhibited greater carbon loss than the pasture soil, most likely due to microbial communities that are adapted to lignin decomposition. These results suggest that rising temperatures combined with changes in vegetation and organic inputs could enhance SOM decomposition and potentially transform the alpine soils from carbon sinks to sources.
{"title":"Availability of labile carbon controls the temperature-dependent response of soil organic matter decomposition in alpine soils","authors":"Dario Püntener, Tatjana Carina Speckert, Yves-Alain Brügger, Guido Lars Bruno Wiesenberg","doi":"10.5194/egusphere-2025-1546","DOIUrl":"https://doi.org/10.5194/egusphere-2025-1546","url":null,"abstract":"<strong>Abstract.</strong> Soil organic matter (SOM) decomposition in alpine environments is influenced by multiple factors including temperature and substrate quality. As climate change will have an impact on both factors, it is essential to improve our knowledge, how, e.g., warming will modify carbon cycling in these environments to better prepare soil management for future conditions, even in alpine regions. This study investigates how warming and organic inputs affect SOM decomposition in alpine forest and pasture soils through a one-year laboratory incubation experiment. Soils were exposed to three temperatures (12.5 °C, 16.5 °C and 20.5 °C), with and without the addition of fresh grass litter. While higher temperatures accelerated decomposition, the availability of fresh organic matter played a more decisive role, especially in the lignin-rich forest soil. Without fresh litter, SOM decomposition was limited, suggesting that substrate availability in combination with temperature increase plays a greater role in microbial activity than temperature alone. The forest soil exhibited greater carbon loss than the pasture soil, most likely due to microbial communities that are adapted to lignin decomposition. These results suggest that rising temperatures combined with changes in vegetation and organic inputs could enhance SOM decomposition and potentially transform the alpine soils from carbon sinks to sources.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"221 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143884554","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}
Pub Date : 2025-04-29DOI: 10.5194/soil-11-339-2025
Margot Vanheukelom, Nina Haenen, Talal Almahayni, Lieve Sweeck, Nancy Weyns, May Van Hees, Erik Smolders
Abstract. The transfer of radiocaesium (137Cs) from soil to crops is the main long-term radiation risk after nuclear accidents. The prevailing concept is that 137Cs sorption in soil – and, hence, its bioavailability – is controlled by soil clay content (0–2 µm). This study tested this assumption using 24 soils collected worldwide. The radiocaesium interception potential (RIP), i.e., 137Cs adsorption, was measured for the bulk soils and for their clay and silt fractions. The RIP varied by a factor of 438 among soils and was unrelated to the clay content (p > 0.05). The RIP in the clay fractions was lowest for young volcanic soils with allophane and mica and for highly weathered tropical soils with kaolinite. In contrast, RIP values about 2 orders of magnitude higher were found in intermediate-weathered temperate soils dominated by illite. Soil RIP was, hence, related to soil illite content (R2= 0.50; p < 0.001). A significant fraction of soil RIP originated from clay minerals embedded in the silt fraction. The sum of RIP in clay and silt fractions overestimated the soil RIP by, on average, a factor of 2, indicating that the isolation of clay opens selective 137Cs sorption sites inaccessible in intact soils. Soil mineralogy, not just clay content, governs soil RIP. In terms of validity, existing 137Cs bioavailability models require recalibration for use on a global scale.
{"title":"The clay mineralogy rather than the clay content determines radiocaesium adsorption in soils on a global scale","authors":"Margot Vanheukelom, Nina Haenen, Talal Almahayni, Lieve Sweeck, Nancy Weyns, May Van Hees, Erik Smolders","doi":"10.5194/soil-11-339-2025","DOIUrl":"https://doi.org/10.5194/soil-11-339-2025","url":null,"abstract":"Abstract. The transfer of radiocaesium (137Cs) from soil to crops is the main long-term radiation risk after nuclear accidents. The prevailing concept is that 137Cs sorption in soil – and, hence, its bioavailability – is controlled by soil clay content (0–2 µm). This study tested this assumption using 24 soils collected worldwide. The radiocaesium interception potential (RIP), i.e., 137Cs adsorption, was measured for the bulk soils and for their clay and silt fractions. The RIP varied by a factor of 438 among soils and was unrelated to the clay content (p > 0.05). The RIP in the clay fractions was lowest for young volcanic soils with allophane and mica and for highly weathered tropical soils with kaolinite. In contrast, RIP values about 2 orders of magnitude higher were found in intermediate-weathered temperate soils dominated by illite. Soil RIP was, hence, related to soil illite content (R2= 0.50; p < 0.001). A significant fraction of soil RIP originated from clay minerals embedded in the silt fraction. The sum of RIP in clay and silt fractions overestimated the soil RIP by, on average, a factor of 2, indicating that the isolation of clay opens selective 137Cs sorption sites inaccessible in intact soils. Soil mineralogy, not just clay content, governs soil RIP. In terms of validity, existing 137Cs bioavailability models require recalibration for use on a global scale.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"272 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143884387","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}
Pub Date : 2025-04-28DOI: 10.5194/soil-11-323-2025
Huan Niu, Can Wang, Xia Luo, Peihan Li, Hang Qiu, Liyue Jiang, Subati Maimaitiaili, Minghui Wu, Fei Xu, Heng Xu
Abstract. The microbial fuel cell (MFC) is an efficient in situ approach to combat pollutants and generate electricity. This study constructed a soil MFC (SMFC) to reduce Cr(VI) in paddy soil and to investigate its influence on microbial community and microbial resistance characteristics. Ferroferric oxide (Fe3O4) nanoparticles, as the cathodic catalyst, effectively boosted power generation (0.97 V, 102.00 mW m−2), with the porous structure and reducibility also contributing to chromium (Cr) reduction and immobilization. After 30 d, 93.67 % of Cr(VI) was eliminated. The bioavailable Cr decreased by 97.44 %, while the residual form increased by 88.89 %. SMFC operations greatly changed soil enzymatic activity and microbial structure, with exoelectrogens like Desulfotomaculum (3.32 % in the anode) and Cr(VI)-reducing bacteria like Hydrogenophaga (2.07 % in the cathode) in more than 1000 folds of soil. In particular, SMFC operations significantly enhanced heavy-metal resistance gene (HRG) abundance. Among them, chrA, chrB, and chrR increased by 99.54 %–3314.34 % in SMFC anodes, probably attributable to the enrichment of potential tolerators like Acinetobacter, Limnohabitans, and Desulfotomaculum. These key taxa were positively correlated with HRGs but were negatively correlated with pH, electrical conductivity (EC), and Cr(VI), which could have driven Cr(VI) reduction. This study provided novel evidence for bio-electrochemical system applications in contaminated paddy soil, which could be a potential approach for environmental remediation and detoxification.
{"title":"Cr(VI) reduction, electricity production, and microbial resistance variation in paddy soil under microbial fuel cell operation","authors":"Huan Niu, Can Wang, Xia Luo, Peihan Li, Hang Qiu, Liyue Jiang, Subati Maimaitiaili, Minghui Wu, Fei Xu, Heng Xu","doi":"10.5194/soil-11-323-2025","DOIUrl":"https://doi.org/10.5194/soil-11-323-2025","url":null,"abstract":"Abstract. The microbial fuel cell (MFC) is an efficient in situ approach to combat pollutants and generate electricity. This study constructed a soil MFC (SMFC) to reduce Cr(VI) in paddy soil and to investigate its influence on microbial community and microbial resistance characteristics. Ferroferric oxide (Fe3O4) nanoparticles, as the cathodic catalyst, effectively boosted power generation (0.97 V, 102.00 mW m−2), with the porous structure and reducibility also contributing to chromium (Cr) reduction and immobilization. After 30 d, 93.67 % of Cr(VI) was eliminated. The bioavailable Cr decreased by 97.44 %, while the residual form increased by 88.89 %. SMFC operations greatly changed soil enzymatic activity and microbial structure, with exoelectrogens like Desulfotomaculum (3.32 % in the anode) and Cr(VI)-reducing bacteria like Hydrogenophaga (2.07 % in the cathode) in more than 1000 folds of soil. In particular, SMFC operations significantly enhanced heavy-metal resistance gene (HRG) abundance. Among them, chrA, chrB, and chrR increased by 99.54 %–3314.34 % in SMFC anodes, probably attributable to the enrichment of potential tolerators like Acinetobacter, Limnohabitans, and Desulfotomaculum. These key taxa were positively correlated with HRGs but were negatively correlated with pH, electrical conductivity (EC), and Cr(VI), which could have driven Cr(VI) reduction. This study provided novel evidence for bio-electrochemical system applications in contaminated paddy soil, which could be a potential approach for environmental remediation and detoxification.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"90 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143880788","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}
Pub Date : 2025-04-24DOI: 10.5194/egusphere-2025-1711
Alejandro Carrascosa, Gerardo Moreno, M. Francesca Cotrufo, Cristina Frade, Sara Rodrigo, Víctor Rolo
Abstract. Soil organic carbon (SOC) storage in semi-arid grasslands is threatened by both climate change and land degradation, impacting food production and climate regulation. Improved management has been proposed to increase SOC stocks and overcome these challenges. However, the benefits of improved management practices in semi-arid regions are in question. Little is known about the effects of management on the functional components of SOC, particulate (POC) and mineral-associated organic carbon (MAOC), which are expected to respond differently, and about the pathways that mediate these responses, such as changes in vegetation and soil microbial communities. This work analyses the effect of rotational grazing, legumes sowing and grazing exclusion on topsoil SOC, POC and MAOC stocks in Mediterranean wooded grasslands compared to continuous conventional grazing. Changes in plant diversity and morpho-chemical traits, soil fertility and microbial composition were also evaluated. A total of 188 plots were sampled in 9 farms across a wide environmental gradient. More resource-acquisitive, nitrogen-rich and less lignified plant community, higher soil microbial biomass with lower Gram+/Gram- ratio, and higher soil fertility were associated with higher SOC storage, with similar impacts on POC and MAOC. Rotational grazing increased MAOC and total SOC stocks by 11 % compared to continuous grazing. This effect was mediated by an increase in soil fertility in the rotationally grazed paddocks. On the other hand, grazing exclusion reduced POC stocks by 12 % compared to continuous grazing. This depletion was mainly due to a reduction in microbial biomass and an increase in the C/N ratio of vegetation in non-grazed paddocks. Both POC and MAOC stocks tended to be lower at the warmer sites. We conclude that rotational grazing can enhance long-term SOC storage in semi-arid grasslands, thereby increasing their resilience and climate mitigation capacity, whereas abandoning grazing could lead to SOC losses.
{"title":"Improved management increases soil mineral-protected organic carbon storage via plant-microbial-nutrient mediation in semi-arid grasslands","authors":"Alejandro Carrascosa, Gerardo Moreno, M. Francesca Cotrufo, Cristina Frade, Sara Rodrigo, Víctor Rolo","doi":"10.5194/egusphere-2025-1711","DOIUrl":"https://doi.org/10.5194/egusphere-2025-1711","url":null,"abstract":"<strong>Abstract.</strong> Soil organic carbon (SOC) storage in semi-arid grasslands is threatened by both climate change and land degradation, impacting food production and climate regulation. Improved management has been proposed to increase SOC stocks and overcome these challenges. However, the benefits of improved management practices in semi-arid regions are in question. Little is known about the effects of management on the functional components of SOC, particulate (POC) and mineral-associated organic carbon (MAOC), which are expected to respond differently, and about the pathways that mediate these responses, such as changes in vegetation and soil microbial communities. This work analyses the effect of rotational grazing, legumes sowing and grazing exclusion on topsoil SOC, POC and MAOC stocks in Mediterranean wooded grasslands compared to continuous conventional grazing. Changes in plant diversity and morpho-chemical traits, soil fertility and microbial composition were also evaluated. A total of 188 plots were sampled in 9 farms across a wide environmental gradient. More resource-acquisitive, nitrogen-rich and less lignified plant community, higher soil microbial biomass with lower Gram+/Gram- ratio, and higher soil fertility were associated with higher SOC storage, with similar impacts on POC and MAOC. Rotational grazing increased MAOC and total SOC stocks by 11 % compared to continuous grazing. This effect was mediated by an increase in soil fertility in the rotationally grazed paddocks. On the other hand, grazing exclusion reduced POC stocks by 12 % compared to continuous grazing. This depletion was mainly due to a reduction in microbial biomass and an increase in the C/N ratio of vegetation in non-grazed paddocks. Both POC and MAOC stocks tended to be lower at the warmer sites. We conclude that rotational grazing can enhance long-term SOC storage in semi-arid grasslands, thereby increasing their resilience and climate mitigation capacity, whereas abandoning grazing could lead to SOC losses.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"70 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143866397","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}
Pub Date : 2025-04-15DOI: 10.5194/egusphere-2025-1667
Arthur Vienne, Patrick Frings, Jet Rijnders, Tim Jesper Suhrhoff, Tom Reershemius, Reinaldy P. Poetra, Jens Hartmann, Harun Niron, Miguel Portillo Estrada, Laura Steinwidder, Lucilla Boito, Sara Vicca
Abstract. Enhanced Weathering using basalt rock dust is a scalable carbon dioxide removal (CDR) technique, but quantifying rock weathering and CDR rates poses a critical challenge. Here, we investigated inorganic CDR and weathering rates by treating mesocosms planted with corn with basalt (0, 10, 30, 50, 75, 100, 150 and 200 t ha⁻¹) and monitoring them for 101 days. Surprisingly, we observed no significant inorganic CDR, as leaching of dissolved inorganic carbon did not increase, and soil carbonate content even declined over time. To gain insights into the weathering processes, we analyzed the mass balance of base cations, which can be linked with anions (including HCO3-) through charge balance. This mass balance showed that most base cation charges were retained as (hydr)oxides in the reducible pool of the top soil, while increases in the exchangeable pool were about a factor 10 smaller. Soil base cation scavenging exceeded plant scavenging by approximately two orders of magnitude. From the base cations in all pools (soil, soil water and plants), we quantified log weathering rates of -11 mol TA m-2 basalt s-1 and a maximum CO2 removal potential of the weathered base cations (i.e., CDR potential) of 18 kg CO2 t⁻¹ basalt. For climate change mitigation, not only the amount of CDR potential is important, but also the timescale at which that CDR would be realized. Our data suggests that the lag time for realization of inorganic CDR may be larger than commonly assumed. In conclusion, we observed that inorganic CDR was not directly linked to rock weathering in the short-term. Still, the observed increases in secondary minerals and base cation exchange may provide valuable benefits for soil fertility and organic matter stabilization in the long-term.
摘要。利用玄武岩粉尘增强风化是一种可扩展的二氧化碳去除(CDR)技术,但对岩石风化和CDR速率进行量化是一个关键挑战。在这里,我们通过用玄武岩(0、10、30、50、75、100、150和200 t ha - 1)处理种植玉米的中胚囊,并对它们进行101天的监测,研究了无机CDR和风化率。令人惊讶的是,我们没有观察到明显的无机CDR,因为溶解无机碳的浸出没有增加,土壤碳酸盐含量甚至随着时间的推移而下降。为了深入了解风化过程,我们分析了碱阳离子的质量平衡,碱阳离子可以通过电荷平衡与阴离子(包括HCO3-)连接。这种质量平衡表明,大多数碱性阳离子在表层土壤的可还原池中以(氢氧)氧化物的形式保留,而在可交换池中增加的量约为1 / 10。土壤碱性阳离子的清除超过植物清除大约两个数量级。从所有池(土壤,土壤水和植物)的碱阳离子中,我们量化了-11 mol TA m-2玄武岩s-1的对数风化速率和18 kg CO2 t -1玄武岩的最大CO2去除电位(即CDR电位)。对于减缓气候变化而言,不仅CDR潜力的数量很重要,而且实现CDR的时间尺度也很重要。我们的数据表明,实现无机CDR的滞后时间可能比通常假设的要大。综上所述,我们观察到无机CDR在短期内与岩石风化没有直接联系。然而,观察到的次生矿物和碱阳离子交换的增加可能为土壤肥力和有机质稳定提供有价值的长期效益。
{"title":"Weathering without inorganic CDR revealed through cation tracing","authors":"Arthur Vienne, Patrick Frings, Jet Rijnders, Tim Jesper Suhrhoff, Tom Reershemius, Reinaldy P. Poetra, Jens Hartmann, Harun Niron, Miguel Portillo Estrada, Laura Steinwidder, Lucilla Boito, Sara Vicca","doi":"10.5194/egusphere-2025-1667","DOIUrl":"https://doi.org/10.5194/egusphere-2025-1667","url":null,"abstract":"<strong>Abstract.</strong> Enhanced Weathering using basalt rock dust is a scalable carbon dioxide removal (CDR) technique, but quantifying rock weathering and CDR rates poses a critical challenge. Here, we investigated inorganic CDR and weathering rates by treating mesocosms planted with corn with basalt (0, 10, 30, 50, 75, 100, 150 and 200 t ha⁻¹) and monitoring them for 101 days. Surprisingly, we observed no significant inorganic CDR, as leaching of dissolved inorganic carbon did not increase, and soil carbonate content even declined over time. To gain insights into the weathering processes, we analyzed the mass balance of base cations, which can be linked with anions (including HCO<sub>3</sub><sup>-</sup>) through charge balance. This mass balance showed that most base cation charges were retained as (hydr)oxides in the reducible pool of the top soil, while increases in the exchangeable pool were about a factor 10 smaller. Soil base cation scavenging exceeded plant scavenging by approximately two orders of magnitude. From the base cations in all pools (soil, soil water and plants), we quantified log weathering rates of -11 mol TA m<sup>-2</sup> basalt s<sup>-1 </sup>and a maximum CO<sub>2 </sub>removal potential of the weathered base cations (i.e., CDR potential) of 18 kg CO<sub>2</sub> t⁻¹ basalt. For climate change mitigation, not only the amount of CDR potential is important, but also the timescale at which that CDR would be realized. Our data suggests that the lag time for realization of inorganic CDR may be larger than commonly assumed. In conclusion, we observed that inorganic CDR was not directly linked to rock weathering in the short-term. Still, the observed increases in secondary minerals and base cation exchange may provide valuable benefits for soil fertility and organic matter stabilization in the long-term.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"234 1 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143832511","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}
Pub Date : 2025-04-14DOI: 10.5194/egusphere-2025-1166
Jayson Gabriel Pinza, Ona-Abeni Devos Stoffels, Robrecht Debbaut, Jan Staes, Jan Vanderborght, Patrick Willems, Sarah Garré
Abstract. Numerical models can quantify subsoil compaction’s hydrological impacts, useful to evaluate water management measures for climate change adaptations on compacted subsoils (e.g., augmenting groundwater recharge). Compaction also affects vegetation growth, which, however, is often parameterized using only limited field measurements or relations with other variables. Our study shows that uncertainties in vegetation parameters linked to transpiration (leaf area index [LAI]) and water uptake (root depth distribution) can significantly affect hydrological modeling outcomes. We used the HYDRUS-1D soil water flow model to simulate the soil water balance of experimental grass plots on Belgian Campine Region’s sandy soil. The compacted plot has the compact subsoil at 40–55 cm depths while the non-compacted plot underwent de-compaction. Using two year soil moisture sensor data at two depths, we calibrated and validated our models of these compacted and non-compacted plots under three different vegetation parameterizations, reflecting various canopy and root growth reactions to compaction. We then simulated the water balances under future climate scenarios. Our experiments reveal that the compacted plots exhibited lower LAI while the non-compacted plots had deeper roots. Considering these vegetations’ reactions in models, our simulations show that compaction will not always reduce deep percolation, compensated by the deep rooted non-compacted case model’s higher evapotranspiration. Therefore, this affected vegetation growth can also further influence the water balance. Hence, hydrological modeling studies on (de-)compaction should dynamically incorporate vegetation growth above- and belowground, of which field evidence is vital.
{"title":"Quantifying hydrological impacts of compacted sandy subsoils using soil water flow simulations: the importance of vegetation parameterization","authors":"Jayson Gabriel Pinza, Ona-Abeni Devos Stoffels, Robrecht Debbaut, Jan Staes, Jan Vanderborght, Patrick Willems, Sarah Garré","doi":"10.5194/egusphere-2025-1166","DOIUrl":"https://doi.org/10.5194/egusphere-2025-1166","url":null,"abstract":"<strong>Abstract.</strong> Numerical models can quantify subsoil compaction’s hydrological impacts, useful to evaluate water management measures for climate change adaptations on compacted subsoils (e.g., augmenting groundwater recharge). Compaction also affects vegetation growth, which, however, is often parameterized using only limited field measurements or relations with other variables. Our study shows that uncertainties in vegetation parameters linked to transpiration (leaf area index [LAI]) and water uptake (root depth distribution) can significantly affect hydrological modeling outcomes. We used the HYDRUS-1D soil water flow model to simulate the soil water balance of experimental grass plots on Belgian Campine Region’s sandy soil. The compacted plot has the compact subsoil at 40–55 cm depths while the non-compacted plot underwent de-compaction. Using two year soil moisture sensor data at two depths, we calibrated and validated our models of these compacted and non-compacted plots under three different vegetation parameterizations, reflecting various canopy and root growth reactions to compaction. We then simulated the water balances under future climate scenarios. Our experiments reveal that the compacted plots exhibited lower LAI while the non-compacted plots had deeper roots. Considering these vegetations’ reactions in models, our simulations show that compaction will not always reduce deep percolation, compensated by the deep rooted non-compacted case model’s higher evapotranspiration. Therefore, this affected vegetation growth can also further influence the water balance. Hence, hydrological modeling studies on (de-)compaction should dynamically incorporate vegetation growth above- and belowground, of which field evidence is vital.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"20 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143827665","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}
Pub Date : 2025-04-09DOI: 10.5194/soil-11-309-2025
Eunji Byun, Fereidoun Rezanezhad, Stephanie Slowinski, Christina Lam, Saraswati Bhusal, Stephanie Wright, William L. Quinton, Kara L. Webster, Philippe Van Cappellen
Abstract. Impacts of nutrient enrichment on soil carbon cycling have been extensively studied in temperate and tropical regions where intensive agriculture and land development has led to large increases in anthropogenic inputs of nitrogen (N) and phosphorous (P). However, how soil carbon sequestration and soil–atmosphere gas exchanges in cold regions respond to greater inputs of N and P remains poorly known despite recent observations showing significant increases in porewater N and P in burned subarctic peatlands and downstream waters. Wildfires and enhanced hydrological connectivity due to permafrost thaw therefore have the potential to change carbon turnover and gas emissions in the soils of northern peatlands. To start exploring the sensitivity of peatland soil biogeochemistry to variations in N and P availability, we measured the carbon dioxide (CO2) and methane (CH4) production rates during a month-long incubation experiment with soils from a bog and fen collected at the long-term Scotty Creek research station in the Northwest Territories, Canada. Sub-samples of the peatland soils were divided into containers to which artificial porewater solutions were added. These solutions were amended with either dissolved inorganic N, dissolved inorganic P, or dissolved N and P together. Unamended controls were run in parallel. The containers were cycled through pre-set temperature steps of 1, 5, 15, and 25 °C. Overall, the fen soil yielded higher CO2 and CH4 production rates than the bog soil. The amendment of N in the bog soil produced more CO2 compared to its control, while the amendment of P increased CO2 production in the fen soil. The amendment of N and P together reduced CO2 production but increased that of CH4 in both the fen and bog soil incubations. Porewater chemistry at the end of the 30 d experiment showed aqueous C, N, and P stoichiometric ratios that trended toward those of the soil microbial biomasses, hence implying that the initial microbial nutrient status played a crucial role in determining the responses to the different nutrient amendments. Our results demonstrate that porewater nutrient availability and soil carbon cycling interact in complex ways to change CO2 and CH4 production rates in peatland soils, with potentially far-reaching implications for the impacts of wildfires and permafrost thaw on peatland–atmosphere carbon exchanges.
{"title":"Effects of nitrogen and phosphorus amendments on CO2 and CH4 production in peat soils of Scotty Creek, Northwest Territories: potential considerations for wildfire and permafrost thaw impacts on peatland carbon exchanges","authors":"Eunji Byun, Fereidoun Rezanezhad, Stephanie Slowinski, Christina Lam, Saraswati Bhusal, Stephanie Wright, William L. Quinton, Kara L. Webster, Philippe Van Cappellen","doi":"10.5194/soil-11-309-2025","DOIUrl":"https://doi.org/10.5194/soil-11-309-2025","url":null,"abstract":"Abstract. Impacts of nutrient enrichment on soil carbon cycling have been extensively studied in temperate and tropical regions where intensive agriculture and land development has led to large increases in anthropogenic inputs of nitrogen (N) and phosphorous (P). However, how soil carbon sequestration and soil–atmosphere gas exchanges in cold regions respond to greater inputs of N and P remains poorly known despite recent observations showing significant increases in porewater N and P in burned subarctic peatlands and downstream waters. Wildfires and enhanced hydrological connectivity due to permafrost thaw therefore have the potential to change carbon turnover and gas emissions in the soils of northern peatlands. To start exploring the sensitivity of peatland soil biogeochemistry to variations in N and P availability, we measured the carbon dioxide (CO2) and methane (CH4) production rates during a month-long incubation experiment with soils from a bog and fen collected at the long-term Scotty Creek research station in the Northwest Territories, Canada. Sub-samples of the peatland soils were divided into containers to which artificial porewater solutions were added. These solutions were amended with either dissolved inorganic N, dissolved inorganic P, or dissolved N and P together. Unamended controls were run in parallel. The containers were cycled through pre-set temperature steps of 1, 5, 15, and 25 °C. Overall, the fen soil yielded higher CO2 and CH4 production rates than the bog soil. The amendment of N in the bog soil produced more CO2 compared to its control, while the amendment of P increased CO2 production in the fen soil. The amendment of N and P together reduced CO2 production but increased that of CH4 in both the fen and bog soil incubations. Porewater chemistry at the end of the 30 d experiment showed aqueous C, N, and P stoichiometric ratios that trended toward those of the soil microbial biomasses, hence implying that the initial microbial nutrient status played a crucial role in determining the responses to the different nutrient amendments. Our results demonstrate that porewater nutrient availability and soil carbon cycling interact in complex ways to change CO2 and CH4 production rates in peatland soils, with potentially far-reaching implications for the impacts of wildfires and permafrost thaw on peatland–atmosphere carbon exchanges.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"96 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143805730","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}
Pub Date : 2025-04-08DOI: 10.5194/soil-11-287-2025
Marliana Tri Widyastuti, José Padarian, Budiman Minasny, Mathew Webb, Muh Taufik, Darren Kidd
Abstract. Soil moisture, an essential parameter for hydroclimatic studies, exhibits considerable spatial and temporal variability, which complicates its mapping at high spatiotemporal resolutions. Although current remote sensing products offer global estimates of soil moisture at fine temporal resolutions, they do so at a coarse spatial resolution. Deep learning (DL) techniques have recently been employed to produce high-resolution maps of various soil properties; however, these methods require substantial training data. This study sought to map daily soil moisture across Tasmania, Australia, at an 80 m resolution using a limited set of training data. We assessed three modeling strategies: DL models calibrated using an Australian dataset (51 411 observation points), models calibrated using the Tasmanian dataset (9825 observation points), and a transfer learning technique that transferred information from the Australian models to Tasmania using region-specific data. We also evaluated two DL approaches, i.e., multilayer perceptron (MLP) and long short-term memory (LSTM). The models included the Soil Moisture Active Passive (SMAP) dataset, weather data, an elevation map, land cover, and multilevel soil property maps as inputs to generate soil moisture at the surface (0–30 cm) and subsurface (30–60 cm) layers. Results showed that (1) models calibrated from the Australian dataset performed worse than Tasmanian models regardless of the type of DL approaches; (2) Tasmanian models, calibrated solely using local data, resulted in shortcomings in predicting soil moisture; and (3) transfer learning exhibited remarkable performance improvements (error reductions of up to 45 % and a 50 % increase in correlation) and resolved the drawbacks of the two previous models. The LSTM models with transfer learning had the highest overall performance with an average mean absolute error (MAE) of 0.07 m3 m−3 and a correlation coefficient (r) of 0.77 across stations for the surface layer as well as MAE=0.07m3m-3 and r=0.69 for the subsurface layer. The fine-resolution soil moisture maps captured the detailed landscape variation as well as temporal variation according to four distinct seasons in Tasmania. The models were then applied to generate daily soil moisture maps of Tasmania, integrated into a near-real-time monitoring system to assist agricultural decision-making.
{"title":"Mapping near-real-time soil moisture dynamics over Tasmania with transfer learning","authors":"Marliana Tri Widyastuti, José Padarian, Budiman Minasny, Mathew Webb, Muh Taufik, Darren Kidd","doi":"10.5194/soil-11-287-2025","DOIUrl":"https://doi.org/10.5194/soil-11-287-2025","url":null,"abstract":"Abstract. Soil moisture, an essential parameter for hydroclimatic studies, exhibits considerable spatial and temporal variability, which complicates its mapping at high spatiotemporal resolutions. Although current remote sensing products offer global estimates of soil moisture at fine temporal resolutions, they do so at a coarse spatial resolution. Deep learning (DL) techniques have recently been employed to produce high-resolution maps of various soil properties; however, these methods require substantial training data. This study sought to map daily soil moisture across Tasmania, Australia, at an 80 m resolution using a limited set of training data. We assessed three modeling strategies: DL models calibrated using an Australian dataset (51 411 observation points), models calibrated using the Tasmanian dataset (9825 observation points), and a transfer learning technique that transferred information from the Australian models to Tasmania using region-specific data. We also evaluated two DL approaches, i.e., multilayer perceptron (MLP) and long short-term memory (LSTM). The models included the Soil Moisture Active Passive (SMAP) dataset, weather data, an elevation map, land cover, and multilevel soil property maps as inputs to generate soil moisture at the surface (0–30 cm) and subsurface (30–60 cm) layers. Results showed that (1) models calibrated from the Australian dataset performed worse than Tasmanian models regardless of the type of DL approaches; (2) Tasmanian models, calibrated solely using local data, resulted in shortcomings in predicting soil moisture; and (3) transfer learning exhibited remarkable performance improvements (error reductions of up to 45 % and a 50 % increase in correlation) and resolved the drawbacks of the two previous models. The LSTM models with transfer learning had the highest overall performance with an average mean absolute error (MAE) of 0.07 m3 m−3 and a correlation coefficient (r) of 0.77 across stations for the surface layer as well as MAE=0.07m3m-3 and r=0.69 for the subsurface layer. The fine-resolution soil moisture maps captured the detailed landscape variation as well as temporal variation according to four distinct seasons in Tasmania. The models were then applied to generate daily soil moisture maps of Tasmania, integrated into a near-real-time monitoring system to assist agricultural decision-making.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"43 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143805731","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}