Soil最新文献

{"title":"Modelling of post-monsoon drying in Nepal: implications for landslide hazard","authors":"Maximillian Van Wyk de Vries, Sihan Li, Katherine Arrell, Jeevan Baniya, Dipak Basnet, Gopi K. Basyal, Nyima Dorjee Bhotia, Alexander L. Densmore, Tek Bahadur Dong, Alexandre Dunant, Erin L. Harvey, Ganesh K. Jimee, Mark E. Kincey, Katie Oven, Sarmila Paudyal, Dammar Singh Pujara, Anuradha Puri, Ram Shrestha, Nick J. Rosser, Simon J. Dadson","doi":"10.5194/egusphere-2024-397","DOIUrl":"https://doi.org/10.5194/egusphere-2024-397","url":null,"abstract":"<strong>Abstract.</strong> Soil moisture is a key preconditioning factor influencing hillslope stability and the initiation of landslides. Direct measurements of soil moisture on a large scale are logistically complicated, expensive, and therefore sparse, resulting in large data gaps. In this study, we calibrate a numerical land surface model to improve our representation of post-monsoon soil drying in landslide-prone Nepal. We use a parameter perturbation experiment to identify optimal parameter sets at three field monitoring sites and evaluate the performance of those optimal parameter sets at each location. This process enables the calibration of key soil hydraulic parameters, in particular a higher hydraulic conductivity and a lower saturation moisture content relative to the default parameter setting. Runs with the calibrated model parameters provide a substantially more accurate (50 % or greater reduction in root mean squared error) soil moisture record than those with the default model parameters, even when calibrated from sites as much as 250 km apart. This process enables meaningful calculation of post-monsoon soil moisture decay at locations with no in situ monitoring, so as to inform a key component of landslide susceptibility mapping in Nepal and other regions where field measurements of soil moisture are limited.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"180 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140209872","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/egusphere-2024-637","DOIUrl":"https://doi.org/10.5194/egusphere-2024-637","url":null,"abstract":"&lt;strong&gt;Abstract.&lt;/strong&gt; This integrated pedo-geoarchaeological study focuses on three abandoned prehispanic terrace agricultural systems near Laramate in the southern Andes of Peru, aiming to unravel the pedological and land-use history of the region. The investigation involved contextualizing the former agricultural management system within its paleoecological framework and assessing the impact of agricultural practices on soil development and quality. The Laramate terrace complex, with its diverse terrace systems and varied geomorphological settings, provided an ideal setting for the investigation. Comparative analyses between non-irrigated agricultural terrace soils and undisturbed reference sequences were conducted, employing a range of methodologies, including surveys, soil analysis, GIS and remote sensing, palaeobotany, and radiocarbon dating. The study identifies three WRB Reference Soil Groups in the Laramate region: &lt;em&gt;Phaeozems&lt;/em&gt;, &lt;em&gt;Andosols&lt;/em&gt;, and &lt;em&gt;Anthrosols&lt;/em&gt;. Unique characteristics of &lt;em&gt;Phaeozems&lt;/em&gt; challenge typical descriptions, influenced by factors such as climatic seasonality, vegetation, fauna, lithology, and aeolian inputs. Despite long-term use, terrace soils (&lt;em&gt;Anthrosols&lt;/em&gt;) show no severe degradation, maintaining balanced acidity and nutrient availability for successful crop cultivation. Tillage horizons of all terrace soils exhibit elevated organic matter content, highlighting the sustainability of prehispanic agricultural practices through a consistent application of organic manure. Phytolith concentrations indicate extensive agricultural activities, particularly maize cultivation, with varying patterns suggesting changes in cultivation or fertilization practices over time. Starch grain identification aligns with phytolith analyses, reinforcing maize's significance in the region. Notably, the abandonment of the prehispanic cultivation system was not linked to soil exhaustion or terrace instability. The prehispanic history of terraced agriculture in the Laramate region extends over four development phases, reflecting dynamic interactions between environmental, cultural, and agricultural factors. The initial phase, from the Formative Paracas period to the Early Nasca period (800 BCE–200 CE), witnessed the establishment of agricultural terraces with simple terrace architecture, while the Middle Horizon (600–1000 CE) saw systematic areal expansion influenced by the Wari culture. Adaptations to drier conditions included terraced agriculture on volcanic soils. The Late Intermediate Period (1000–1450 CE) witnessed hydrological variability and further terrace expansion to lower altitudes and less agriculturally suitable locations. The final phase, marked by the onset of the Hispanic colonial period in 1532 CE, saw the gradual abandonment of terraced agricultural systems due to demographic shifts and reorganization of production systems. Despite this, the historical trajectory underscores the adaptabili","PeriodicalId":48610,"journal":{"name":"Soil","volume":"25 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140104628","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":"Model-based analysis of erosion-induced microplastic delivery from arable land to the stream network of a mesoscale catchment","authors":"Raphael Rehm, Peter Fiener","doi":"10.5194/soil-10-211-2024","DOIUrl":"https://doi.org/10.5194/soil-10-211-2024","url":null,"abstract":"Abstract. Soils are generally accepted as sinks for microplastics (MPs) but at the same time might be an MP source for inland waters. However, little is known regarding the potential MP delivery from soils to aquatic systems via surface runoff and erosion. This study provides, for the first time, an estimate of the extent of soil-erosion-induced MP delivery from an arable-dominated mesoscale catchment (390 km2) to its river network within a typical arable region of southern Germany. To do this, a soil erosion model was used and combined with the potential particular MP load of arable land from different sources (sewage sludge, compost, atmospheric deposition, and tyre wear) from 1950 onwards. The modelling resulted in an annual mean MP flux into the stream network of 6.33 kg MP a−1 in 2020, which was dominated by tyre wear (80 %). Overall, 0.11 %–0.17 % of the MPs applied to arable soils between 1950 and 2020 were transported into the stream network. In terms of mass, this small proportion was in the same range as the MP inputs from wastewater treatment plants within the test catchment. More MP (0.5 %–1 % of input between 1950 and 2020) was deposited in the grassland areas along the stream network, and this could be an additional source of MP during flood events. Most (5 % of the MP applied between 1950 and 2020) of the MP translocated by tillage and water erosion was buried under the plough layer. Thus, the main part of the MP added to arable land remained in the topsoil and is available for long-term soil erosion. This can be illustrated based on a “stop MP input in 2020” scenario, indicating that MP delivery to the stream network until 2100 would only be reduced by 14 %. Overall, arable land at risk of soil erosion represents a long-term MP sink but also a long-term MP source for inland waters.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"91 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140104698","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":"Vitezslav Vlcek, 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/egusphere-2024-607","DOIUrl":"https://doi.org/10.5194/egusphere-2024-607","url":null,"abstract":"<strong>Abstract.</strong> Around half of the Earth’s soil organic carbon (SOC) is presently stored in the Northern permafrost region. In polar permafrost regions, low temperatures particularly inhibit both the production and biodegradation of organic matter. In 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 at the deglaciated area of James Ross Island (Ulu Peninsula) with a parallel tea-bag soil proteins (EE-GRSP; Spearman r = 0.733, <em>P</em>=0.031) and the soil buffer capacity (expressed as a ΔpH; Spearman r = 0.817, <em>P</em>=0.011). The soil available P was negatively correlated with altitude (Spearman r = -0.711, <em>P</em>=0.032) and the exchangeable Mg was negatively correlated to the content of rock fragments (Spearman r = -0.683, <em>P</em>=0.050)No correlation was found between the available mineral nutrients (P, K, Ca, Mg) and SOC nor 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 decomposition experiment. SOC contents showed a positive correlation with the contents of easily extractable glomalin-related seems to be not the biotic, but rather the abiotic environment influencing the mesoclimate (altitude) or the level of weathering (rock content). Incubation in tea bags for 45 days resulted in the consumption and/or translocation of more labile polyphenolic and water-extractable organic matter, along with changes in 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 SOC/GRSP content is not altitude or coarse fraction content (whose correlation with SOC/GRSP were not found) but probably other factors that are difficult to quantify, such as the availability of liquid water.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"285 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140104842","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":"Impact of Cropping Systems on Macronutrient Distribution and Microbial Biomass in Drought Affected Soils","authors":"M. Naga Jayasudha, M. Kiranmai Reddy, Surendra Singh Bargali","doi":"10.5194/egusphere-2024-40","DOIUrl":"https://doi.org/10.5194/egusphere-2024-40","url":null,"abstract":"<strong>Abstract.</strong> The interplay between soil nutrients, water activity, and microbial biomass is pivotal for plant growth as well as for soil health. While surface microflora typically promotes mineralization and nutrient deposits, the impact of drought on soil microbial biomass and nutrient utilization remains underexplored. In this study, we assessed various land types—open lands (OL), annual crops with single species (ACS), perennial crops with multiple species (PCM), less water available lands (LWA), and soil near ponds (CP)—to elucidate the distribution of macronutrients and microbial biomass. Soil samples were collected from different land types, air-dried, and subjected to physical, chemical, and biological analyses. Standardized protocols, including gravimetric and titration analyses, were employed for physical and chemical assessments, while microbial biomass was evaluated using fumigation. Statistical analyses, including ANOVA and Pearson Coefficient, were employed to discern patterns across seasons, soil depths, and microbial biomass. Microbial biomass carbon (Cmic) ranged from 134.2±1.2 μg/g to 286.6±1.33 μg/g, while nitrogen (Nmic) and phosphorus (Pmic) varied from 11.3±1.3 μg/g to 69.5±0.98 μg/g and 07.6±1.5 μg/g to 77.5±0.6 μg/g, respectively, across all seasons. Carbon stock in the upper soil surface positively influenced nitrogen and phosphorus retention. Notably, PCM exhibited superior Cmic, Nmic, Pmic, and water-holding capacity compared to OL, LWA, and ACS. Our findings underscore the significance of multiple cropping systems, particularly PCM, in enhancing microbial biomass and nutrient levels in drought-affected regions. The observed improvements in soil moisture, nitrogen, phosphorous, and potassium levels suggest that diverse cropping systems can effectively enrich soil nutrients and biomass content in drought stress. In conclusion, our study highlights the potential of perennial crops with multiple species in mitigating the impact of drought on soil microbial biomass and macronutrient distribution. These findings contribute to a deeper understanding of sustainable agricultural practices in drought-prone regions and emphasize the importance of implementing diverse cropping systems to enhance soil health and resilience.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"2 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140104629","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":"Impacts of soil storage on microbial parameters","authors":"Nathalie Fromin","doi":"10.5194/egusphere-2024-411","DOIUrl":"https://doi.org/10.5194/egusphere-2024-411","url":null,"abstract":"<strong>Abstract.</strong> This review aims to determine the impact of soil storage on microbial parameters (abundance/biomass, activity and various diversity metrics). We analysed the literature dealing with the impact of storage practices (cold, freeze, dry, freeze-dry and ambient storage) on soil microbial parameters. A total of 73 articles were included in the analysis, representing 261 basic data (impact of a given storage practice on a microbial parameter). Globally, 74 % of these data showed significant impact of storage on the measured microbial parameters, as compared to those measured on fresh, non-stored soil samples. The storage practices showed various effects on the soil microbial parameters, with sometimes opposite effects across different soil types. For instance, various soil enzyme activities did not respond the same way to storage practices, even in a given soil type. There are currently too few studies to draw recommendations, but some studies suggest that the pedoclimatic context could be useful for choosing the best storage option, with soils that regularly undergo drought or freezing being less impacted by dry and freeze storage, respectively. I conclude that storage practices for soil samples, when unavoidable, should be carefully selected according to conditions that prevail in the native soil environment, to microbial parameters that are analysed (even though there is no consensus for a best practice), and with different storage practices for different microbial parameters if necessary.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"15 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140114792","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":"Diachronic assessment of soil organic C and N dynamics under long-term no-till cropping systems in the tropical upland of Cambodia","authors":"Vira Leng, Rémi Cardinael, Florent Tivet, Vang Seng, Phearum Mark, Pascal Lienhard, Titouan Filloux, Johan Six, Lyda Hok, Stéphane Boulakia, Clever Briedis, João Carlos de Moraes Sá, Laurent Thuriès","doi":"10.5194/egusphere-2024-541","DOIUrl":"https://doi.org/10.5194/egusphere-2024-541","url":null,"abstract":"&lt;strong&gt;Abstract.&lt;/strong&gt; No-till (NT) cropping systems have been proposed as a potential strategy to combat soil degradation and global warming by storing soil organic carbon (SOC) and nitrogen (N). Yet, there are ongoing debates about the real benefits of NT systems and factors influencing SOC and N accumulation. Assessing the dynamics of SOC and N on the long-term is needed to fill knowledge gaps and provide robust scientific evidence for potential additional SOC storage. We quantified the changes in SOC and N stocks and fractions down to 100 cm depth from three 13-year-old experiments in a tropical red Oxisol in Cambodia, comparing conventional tillage (CT) to NT monocropping and NT crop rotation systems using a diachronic and equivalent soil mass (ESM) approach. The three experiments comprised maize-, soybean-, and cassava-based cropping system trials, hereafter called MaiEx, SoyEx, and CasEx, respectively. Soil samples were collected in 2021, 10 years after the first sampling in 2011, at 7 depths: 0–5, 5–10, 10–20, 20–40, 40–60, 60–80, and 80–100 cm. Over the 10-year period (2011–2021), significant impacts on SOC stock and its vertical distribution differed among the NT systems and in the three experiments. In MaiEx and CasEx, the soils under all the NT systems significantly (P &gt; 0.05) accumulated SOC stock across the soil depths, with the accumulation ranging from 6.97 to 14.71 Mg C ha&lt;sup&gt;-1&lt;/sup&gt; in the whole profile (0–100 cm). In SoyEx, significant increase in SOC stock was limited to the top 0–20 cm under NT monocropping, whereas NT crop rotation systems had significantly accumulating SOC stock from 0 to 80 cm depths. When considering 0–100 cm as a single stratum, the annual SOC cumulative rate in NT systems ranged from 0.86–1.47, 0.65–1.00, and 0.70–1.07 Mg C ha&lt;sup&gt;-1&lt;/sup&gt; yr&lt;sup&gt;-1&lt;/sup&gt; in MaiEx, SoyEx, and CasEx, respectively. In the top 0–10 cm, NT systems significantly increased C concentration in particulate organic matter (POM) by 115 %, 118 %, in MaiEx and SoyEx, respectively, and by 37 % in CasEx although not significantly. Similarly, at 0–10 cm depth, NT systems significantly enhanced C concentration in the mineral-associated organic matter (MAOM) by 33 %, 21 %, in MaiEx and SoyEx, respectively. Significant increase of C in MAOM was also observed from 0 to 40 cm in CasEx. In contrast, total N stock in NT systems increased in the surface 0–5 cm depth but decreased below 10 cm and in the whole profile (0–100 cm), particularly under NT monocropping with an annual loss rate of -0.10 and -0.17 Mg N ha&lt;sup&gt;-1&lt;/sup&gt; yr&lt;sup&gt;-1&lt;/sup&gt; in SoyEx and CasEx, respectively. Although NT systems increased N concentration in POM in the top 0–10 cm of MaiEx and SoyEx, a decreasing trend was observed below 10 cm depth. The N concentration in POM under NT systems in CasEx also decreased with soil depth. From 2011 to 2021, N concentration in MAOM under NT systems remained stable in MaiEx and SoyEx in the top 0–5 cm, but significant decrease","PeriodicalId":48610,"journal":{"name":"Soil","volume":"86 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140069768","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":"Reference soil groups map of Ethiopia based on legacy data and machine learning-technique: EthioSoilGrids 1.0","authors":"Ashenafi Ali, Teklu Erkossa, Kiflu Gudeta, Wuletawu Abera, Ephrem Mesfin, Terefe Mekete, Mitiku Haile, Wondwosen Haile, Assefa Abegaz, Demeke Tafesse, Gebeyhu Belay, Mekonen Getahun, Sheleme Beyene, Mohamed Assen, Alemayehu Regassa, Yihenew G. Selassie, Solomon Tadesse, Dawit Abebe, Yitbarek Wolde, Nesru Hussien, Abebe Yirdaw, Addisu Mera, Tesema Admas, Feyera Wakoya, Awgachew Legesse, Nigat Tessema, Ayele Abebe, Simret Gebremariam, Yismaw Aregaw, Bizuayehu Abebaw, Damtew Bekele, Eylachew Zewdie, Steffen Schulz, Lulseged Tamene, Eyasu Elias","doi":"10.5194/soil-10-189-2024","DOIUrl":"https://doi.org/10.5194/soil-10-189-2024","url":null,"abstract":"Abstract. Up-to-date digital soil resource information and its comprehensive understanding are crucial to supporting crop production and sustainable agricultural development. Generating such information through conventional approaches consumes time and resources, and is difficult for developing countries. In Ethiopia, the soil resource map that was in use is qualitative, dated (since 1984), and small scaled (1 : 2 M), which limit its practical applicability. Yet, a large legacy soil profile dataset accumulated over time and the emerging machine-learning modeling approaches can help in generating a high-quality quantitative digital soil map that can provide better soil information. Thus, a group of researchers formed a Coalition of the Willing for soil and agronomy data-sharing and collated about 20 000 soil profile data and stored them in a central database. The data were cleaned and harmonized using the latest soil profile data template and 14 681 profile data were prepared for modeling. Random forest was used to develop a continuous quantitative digital map of 18 World Reference Base (WRB) soil groups at 250 m resolution by integrating environmental covariates representing major soil-forming factors. The map was validated by experts through a rigorous process involving senior soil specialists or pedologists checking the map based on purposely selected district-level geographic windows across Ethiopia. The map is expected to be of tremendous value for soil management and other land-based development planning, given its improved spatial resolution and quantitative digital representation.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"85 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140032171","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 effect of groundwater depth on topsoil organic matter mineralization during a simulated dry summer in North-West Europe","authors":"Astrid Françoys, Orly Mendoza, Junwei Hu, Pascal Boeckx, Wim Cornelis, Stefaan De Neve, Steven Sleutel","doi":"10.5194/egusphere-2024-559","DOIUrl":"https://doi.org/10.5194/egusphere-2024-559","url":null,"abstract":"<strong>Abstract.</strong> With climate change expected to intensify the occurrence and severity of droughts, the control of groundwater table (GWT) depth and capillary rise on topsoil moisture may render a critical driver of biological activity. Consequently, GWT depth could influence topsoil carbon mineralization. In this study, undisturbed 200 cm long soil columns of three different textures (loamy sand, sandy loam and silt loam) were subjected to two artificial GWT depths (–165 cm and –115 cm) in the laboratory. We examined (1) moisture supply by capillary rise along the soil profile and specifically into the top 20 cm soil, and (2) consequently the effect of GWT on decomposition of an added ¹³C-enriched substrate (ryegrass) over a period of ten weeks, with limited water applications representing a dry summer. A 50 cm difference in GWT depth (–165 cm vs. –115 cm) resulted in different topsoil moisture for the sandy loam (31 % vs. 38 % Water-filled pore space (WFPS)) and silt loam (33 % vs. 43 % WFPS) soils. In the loamy sand soil, GWT-induced moisture differences appeared only up to 85 cm above the GWT. The expected acceleration of mineralization of the added ryegrass under a shallower GWT was not confirmed. In contrast, C mineralization pulses after the wetting events were even higher for the drier –165 cm GWT soils. For the silt loam soil, where capillary rise supply had the largest contribution to topsoil moisture, a lower mineralization rate of the stable C_ryegrass pool was also found with shallower GWT. These findings suggest that a potential capillary rise effect of increased topsoil moisture on ryegrass mineralization might have been counteracted by other processes. We postulate that the Birch effect might have been magnified following the rewetting of drier topsoils under deeper GWT levels, ultimately enhancing mineralization compared to where the soil remains consistently wetter under shallower GWT levels. Based on our findings, including the process of texture-specific capillary supply from the GWT can be required to adequately simulate moisture in the topsoil during droughts as they occurred over the past summers in North-West Europe, depending on GWT and texture combination. However, the net effect on topsoil C mineralization is complex and correct simulation of C mineralization may require further integration of specific processes connected to fluctuating soil moisture state, such as the Birch effect.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"7 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140032114","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":"Mineral dust and pedogenesis in the alpine critical zone","authors":"Jeffrey S. Munroe, Abigail A. Santis, Elsa J. Soderstrom, Michael J. Tappa, Ann M. Bauer","doi":"10.5194/soil-10-167-2024","DOIUrl":"https://doi.org/10.5194/soil-10-167-2024","url":null,"abstract":"Abstract. The influence of mineral dust deposition on soil formation in the mountain critical zone was evaluated at six sites in southwestern North America. Passive samplers collected dust for 2 years, and representative soil and rock were gathered in the vicinity of each dust sampler. All materials (dust, soil, and rock) were analyzed to determine their mineralogy (with X-ray diffraction), geochemistry (with inductively coupled plasma mass spectrometry (ICP-MS)), and radiogenic isotope fingerprint (87Sr/86Sr and εNd). In addition, the grain size distribution of dust and soil samples was determined with laser scattering, and standard soil fertility analysis was conducted on the soil samples. Results reveal that minerals present in the dust but absent in the local bedrock are detectable in the soil. Similarly, the geochemistry and isotopic fingerprint of soil samples are more similar to dust than to local bedrock. End-member mixing models evaluating soil as a mixture of dust and rock suggest that the fine fractions of the sampled soils are dominated by dust deposition, with dust contents approaching 100 %. Dust content is somewhat higher in soils compared to bedrock types more resistant to weathering. These results emphasize the dominant control that mineral dust deposition can exert on pedogenesis in the mountain critical zone.","PeriodicalId":48610,"journal":{"name":"Soil","volume":"52 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139917401","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}