Journal of Soils and Sediments最新文献

{"title":"Desalination of dredged sediments for beneficial use: a case of study for raising agricultural peatlands","authors":"Maria Barciela-Rial, Wouter van der Star","doi":"10.1007/s11368-024-03875-x","DOIUrl":"https://doi.org/10.1007/s11368-024-03875-x","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>Sediments from marine areas contain salt, limiting beneficial use possibilities. This study investigates the impact of rinsing with fresh water on ion concentration and organic matter (OM) content in marine sediments, and how salinity hinders water release under induction.</p><h3 data-test=\"abstract-sub-heading\">Methods</h3><p>In a lab simulation, marine sediment was mixed with fresh water (1:6 volume ratio) for 5 min at 285 rpm using a HOBART planet N-50 Mixer. An adapted Thermogravimetric Analysis (TGA) procedure determined the OM content and the temperature at which all water was released.</p><h3 data-test=\"abstract-sub-heading\">Results</h3><p>Mixing sediment with fresh water reduced ion concentrations. Monovalent ions like sodium and chloride were released immediately, while higher valence ions like sulfate and phosphate were released gradually. Rinsing with fresh water also reduced OM content. A second mix with the salty supernatant water did not further reduce salinity or OM.</p><h3 data-test=\"abstract-sub-heading\">Conclusion</h3><p>Determining OM content in salty sediments requires continuous mass loss monitoring to identify the temperature at which all water is removed. For agricultural reuse, maintaining nutrient levels and OM while reducing salt content to prevent groundwater salinization is crucial. Supernatant water should be removed promptly after rinsing to halt nutrient removal. The results of this study contribute to beneficial reuse of dredged sediment.</p>","PeriodicalId":17139,"journal":{"name":"Journal of Soils and Sediments","volume":"55 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"“Once upon a time… a beach sand grain”: a bed-time story and scientific outreach activity for young children to increase sediment literacy","authors":"Cristina Ponte Lira, Fátima Valverde, Ana Matias","doi":"10.1007/s11368-024-03903-w","DOIUrl":"https://doi.org/10.1007/s11368-024-03903-w","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>Learning science in early years can cultivate children’s curiosity and enjoyment in exploring the world around them, laying the foundation for the progression of science learning and ultimately increasing science literacy. Here, we present an example of a tailored preschool scientific activity designed to enhance literacy about sediments and illustrate their importance to both humans and nature.</p><h3 data-test=\"abstract-sub-heading\">Methods</h3><p>The activity centres around a captivating story detailing the journey of a sand grain from the mountains to the sea. This storytelling experience is enriched with hands-on observation of various sand grains, informative cards on key topics, and culminates in a creative colouring activity.</p><h3 data-test=\"abstract-sub-heading\">Results</h3><p>To date, the activity has been repeated five times, engaging 110 children (from 2 to 10 years). It has yielded positive outcomes with both preschool and primary school students, as they were actively engaged in the story and delighted in handling and observing the magnified sand grains.</p><h3 data-test=\"abstract-sub-heading\">Conclusions</h3><p>The activity was successfully implemented for preschool and primary school students, fostering engagement with the story and the sand samples. However, while the immediate engagement was evident, the impact on sediment literacy remains to be measured. Future structured evaluations are needed to assess the long-term effectiveness of such initiatives in enhancing sediment literacy among young learners.</p>","PeriodicalId":17139,"journal":{"name":"Journal of Soils and Sediments","volume":"17 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microbial metabolism strengths carbon sequestration and crop yield in upland red soil after long-term ex situ incorporation of straw","authors":"Li Tang, Xiaobin Guo, Daoyou Huang, Xiaomeng Wei, Hao Sheng, Pei Luo, Ping Zhou, Wei Gao, Yan Li, Miaomiao Zhang, Wei Zheng, Jinshui Wu","doi":"10.1007/s11368-024-03894-8","DOIUrl":"https://doi.org/10.1007/s11368-024-03894-8","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>Incorporating rice straw into upland has been adopted as a strategy to increase crop productivity and decrease poisoning to rice from reducing substances accumulation as well as mitigate methane emission from paddy fields in South China. However, the mechanism underlying long-term <i>ex situ</i> incorporation of rice straw in upland on soil organic carbon (SOC) and crop yields through microbial metabolism remains unclear.</p><h3 data-test=\"abstract-sub-heading\">Materials and methods</h3><p>Hence, a field experiment was established to investigate the response mechanism of SOC and crop yields underlying microbe-mediated carbon dynamics with nutrient stoichiometry by <i>ex situ</i> incorporation of rice straw in upland.</p><h3 data-test=\"abstract-sub-heading\">Results and discussion</h3><p>The results showed that the treatment of cropping with chemical fertilizers plus rice straw (SCF) had the highest SOC accumulation rate (0.14 ± 0.03 g C kg⁻¹ yr⁻¹) during the 22-year experimental period. The mean yields of rapeseed and sweet potato were increased by 5.0% and 4.7% in the SCF treatment, correspondingly, compared with the treatment of cropping with chemical fertilizers (CF). Additionally, based on ecoenzymatic stoichiometry, soil microorganisms were found to be co-limited by carbon and phosphorus, which was aggravated by the decrease of soil available nutrients. The SCF treatment exhibited a higher soil microbiomass, resulting in an increased secretion of ecoenzymatic activities to mediate stoichiometric imbalance and mitigate nutrient competition between plant and microbial nutrient limitations. The findings revealed a significant association between stoichiometric imbalance and both SOC and crop yields, respectively.</p><h3 data-test=\"abstract-sub-heading\">Conclusions</h3><p>Therefore, our study indicated that long-term <i>ex situ</i> incorporation of rice straw in upland could be adopted as an effective agricultural management strategy to improve SOC and crop yields.</p>","PeriodicalId":17139,"journal":{"name":"Journal of Soils and Sediments","volume":"42 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259794","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrating soil phosphorus sorption capacity with agronomic indices to improve sustainable P use in agriculture","authors":"Sifan Yang, Blánaid White, Fiona Regan, Nigel Kent, Rebecca L. Hall, Karen Daly","doi":"10.1007/s11368-024-03900-z","DOIUrl":"https://doi.org/10.1007/s11368-024-03900-z","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>Phosphorus (P) sorption processes in soils can influence P plant-availability and influence ‘build-up’ and ‘draw-down’ P cycles. Current fertiliser recommendations do not take these processes into account. This study aimed to integrate soil P sorption behaviour and P agronomic-indices to strengthen P management recommendations.</p><h3 data-test=\"abstract-sub-heading\">Methods</h3><p>Mineral soil covering 35,716-km² of Ireland was characterised by P status (Morgan’s P and Mehlich-3 P), and Langmuir sorption parameters of P sorption maximum capacity (Smax, mg·kg⁻¹) and binding energy (k, L·mg⁻¹).</p><h3 data-test=\"abstract-sub-heading\">Results</h3><p>Segmented regression between Smax and M3-Al (<i>R</i>^<i>2</i> = 0.49) identified a significant change-point at Smax = 450.03 mg·kg⁻¹, at which soils can be placed into ‘low’ (SL_M3-Al) and ‘high’ (SH_M3-Al) P sorbing classes. Sorption parameters in SL_M3-Al did not change with soil P status; however, in high P sorbing soils, sorption parameters significantly correlated with P status. High sorbing soils that are P-deficient (Index 1 and 2) will ‘fix’ P and take longer to build-up plant available P to a value for agronomic production (Index 3). Low P sorbing soils at high P status (Index 4) will decline to Index 3 at faster rates than high P sorbing soils. These soils (SL_M3-Al) are at higher risk of soluble P losses to water because of lower binding energies.</p><h3 data-test=\"abstract-sub-heading\">Conclusions</h3><p>Efficient P fertiliser use can be more effective if soils are delineated into ‘low’ and ‘high’ sorbing soils coupled with soil P status. By integrating P sorption capacities with agronomic soil P indices, fertiliser advice and water quality measures can be targeted and more effective.</p>","PeriodicalId":17139,"journal":{"name":"Journal of Soils and Sediments","volume":"63 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Metal pollution in sediments along the Montenegrin coast, Adriatic Sea: a risk analysis","authors":"Ana Perošević-Bajčeta, Rajko Martinović, Danijela Joksimović, Aleksandra Huter, Neda Bošković","doi":"10.1007/s11368-024-03899-3","DOIUrl":"https://doi.org/10.1007/s11368-024-03899-3","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>The study aims to assess the ecological risks posed by metal contamination in Montenegrin marine sediments, focusing on both Boka Kotorska Bay and the coastal part of the open sea. By analyzing metal concentrations and identifying potential pollution hotspots and sources, the research seeks to contribute to a better understanding of the escalating threats to coastal regions and their ecological implications due to anthropogenic activities.</p><h3 data-test=\"abstract-sub-heading\">Methods</h3><p>Total concentrations of Fe, Mn, Cr, Ni, Zn, Cu, Pb, As, Hg, and Cd were determined in surface sediment samples collected from 10 sites along the Montenegrin coast, targeting areas influenced with different sources and levels of anthropogenic pollution. Statistical analysis was performed, and various pollution indices (contamination factor (<i>C</i>_<i>f</i>), geo-accumulation index (<i>Igeo</i>), potential ecological risk factor (<span>({E}_{r}^{i}))</span>, pollution load index (<i>PLI</i>), risk index (<i>RI</i>), mean ERM quotient (<i>MERMQ</i>), and toxic risk index (<i>TRI</i>)) were calculated to assess contamination status, severity of pollution, and potential ecological risks.</p><h3 data-test=\"abstract-sub-heading\">Results</h3><p>The results showed varying levels of metals, with elevated concentrations of Fe, Mn, Ni, and Cr at location S10 (Ada Bojana), and higher Cu, Pb, Hg, and Zn levels at S5 (Bijela). <i>C</i>_<i>f</i> and <i>Igeo</i> values indicated mainly moderate to considerable pollution, with Pb concentrations of particular concern. Ecological risks were posed by Hg and, in some cases, Cd, while Ni concentrations presented the highest toxic risk to marine organisms according to <i>TRI</i>_<i>i</i> values. Overall, pollution was present in the entire area, with mainly moderate ecological risk according to <i>RI</i> values, but considerable to very high toxic risks highlighted by <i>MERMQ</i> and <i>TRI</i> values at various locations.</p><h3 data-test=\"abstract-sub-heading\">Conclusion</h3><p>This study revealed overall pollution presence in surface sediments along the Montenegrin coast, predominantly associated with anthropogenic sources, thereby posing potential ecological risks, particularly in Boka Kotorska Bay and at S10 (Ada Bojana). The obtained results highlighted the need for continued monitoring and management strategies to mitigate environmental impacts.</p>","PeriodicalId":17139,"journal":{"name":"Journal of Soils and Sediments","volume":"10 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of rill morphology characteristics on particle size selectivity using indoor simulation experiments with two types of soil from the Loess Plateau","authors":"Liying Sun, Qingyuan Dai","doi":"10.1007/s11368-024-03895-7","DOIUrl":"https://doi.org/10.1007/s11368-024-03895-7","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>The relations between rill morphology indicators and particle size selectivity by rainfall events were investigated, providing a new perspective on the mechanism of rill morphology indicators impacting on rill erosion processes.</p><h3 data-test=\"abstract-sub-heading\">Materials and methods</h3><p>Indoor rainfall experiments were carried out with three-dimensional (3D) laser scanning technique for better monitoring the rill morphological indicators, using two types of soil collected from the north part and the south part of the Loess Plateau, respectively.</p><h3 data-test=\"abstract-sub-heading\">Results and discussions</h3><p>The higher degree of headward erosion is occurred on loamy clay (LC) soil from the south part of the Loess Plateau with the higher total length (6.65 m) due to the higher clay content. Higher degree of side erosion is demonstrated on sandy loam (SL) soil from the north part of the Loess Plateau with the higher mean rill width (0.09 ± 0.00 m) due to the higher sand content. The ratios of rill width to depth do not show significant differences on two types of soil with the average value greater than 1, indicating the relatively higher degree of side erosion than downward erosion on both soils. Silt fraction is selected with much higher efficiency than other fractions in two types of soil due to the dominant silt fractions in the primary soil. Rill width (<i>W</i>) is the most sensitive indicator to the particle size selectivity, as both the contents of clay, silt and fine particles and the enrichment ratio of silt show significantly (<i>P</i> &lt; 0.05) positive correlations with <i>W</i>. While, the enrichment ratio of sand fraction shows significantly (<i>P</i> &lt; 0.05) negative correlations with rill maximum depth and degree of contour line departure.</p><h3 data-test=\"abstract-sub-heading\">Conclusions</h3><p>The differences of rill morphology indicators on two types of soil slope mainly depend on soil texture and the development processes of rills.</p>","PeriodicalId":17139,"journal":{"name":"Journal of Soils and Sediments","volume":"39 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isotope signature and ecoenzymatic stoichiometry as key indicators of urban soil functionality","authors":"Francesca Vannucchi, Andrea Scartazza, Cristina Macci, Francesca Bretzel, Serena Doni, Irene Rosellini, Eliana Tassi, Roberto Pini, Grazia Masciandaro, Eleonora Peruzzi","doi":"10.1007/s11368-024-03892-w","DOIUrl":"https://doi.org/10.1007/s11368-024-03892-w","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>This study aimed to assess the feasibility of the ecoenzymatic stoichiometry and isotope signature approaches as indicators of urban soil functionality, related to carbon and nutrient cycles.</p><h3 data-test=\"abstract-sub-heading\">Methods</h3><p>In Pisa and Livorno (Italy), study sites with three degrees of urbanization (natural, peri-urban and central urban sites) were selected, where holm oak (<i>Quercus ilex</i> L.) was the most common evergreen species. The urban and peri-urban sites differed in terms of NO₂ emissions. At each site, topsoil and plant litter were sampled, pH, EC, TOC, and TN were measured in soil and δ¹³C and δ¹⁵N in soil and plant litter. The β-glucosidase, acid phosphatase and N-acetyl-β-D-glucosaminidase enzyme activities were also determined in soil and the ratios were calculated.</p><h3 data-test=\"abstract-sub-heading\">Results</h3><p>The δ¹⁵N in plant litter increased from peri-urban to urban sites, along with the NO₂ emissions, emerging as a sensitive indicator of atmospheric N deposition. The δ¹⁵N and δ¹³C increased in soil, indicating more rapid N cycles and organic matter degradation in peri-urban and urban areas than in natural areas. The ecoenzymatic stoichiometry revealed C and P microbial limitations for all the sites studied. However, the microbial needs of C and P increased and decreased, respectively, along the urbanization gradient. Isotope abundance and microbial nutrient limitations were found to correlate with soil properties. Specifically, soil δ¹⁵N was closely correlated with microbial C limitations.</p><h3 data-test=\"abstract-sub-heading\">Conclusion</h3><p>The isotope signature and enzymatic stoichiometry used as indicators revealed that the soil characteristics affected the soil carbon and nutrient cycles as well as microbial energy and nutrient needs.</p>","PeriodicalId":17139,"journal":{"name":"Journal of Soils and Sediments","volume":"25 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pollution of a Black Sea coastal city: potentially toxic elements in urban soils, road dust, and their PM10 fractions","authors":"Liliya Bezberdaya, Olga Chernitsova, Mikhail Lychagin, Elena Aseeva, Anna Tkachenko, Nikolay Kasimov","doi":"10.1007/s11368-024-03893-9","DOIUrl":"https://doi.org/10.1007/s11368-024-03893-9","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>The study aimed to assess the accumulation levels, spatial distribution, and sources of the potentially toxic elements (PTEs), such as Zn, As, Cd, Pb, Cr, Co, Ni, Cu, Sb, Mo, V, W, Sr, Mn, Bi, Sn, Fe, Cs, Be, and Ba, in urban soils, road dust and their PM₁₀ fractions in Yalta, a seaside resort town of the Crimean Peninsula.</p><h3 data-test=\"abstract-sub-heading\">Materials and methods</h3><p>The concentrations of the PTEs were measured in the urban topsoil (0–10 cm), road dust, and their fine particles, &lt; 10 μm in diameter (PM₁₀), using ICP-MS and ICP-AES methods. The soil and road dust samples were collected in 2018 in various functional zones of Yalta and on different types of roads. In total, 69 soil samples and 57 road-dust samples were taken. The PM₁₀ fraction was isolated by sedimentation method according to Stokes' law.</p><h3 data-test=\"abstract-sub-heading\">Results and discussion</h3><p>The urban soils and the road dust were contaminated by Pb, Sb, Zn, Sn, Cd, Cu, Bi, Mo, and Mn. The finer particles (PM₁₀) separated from the urban soils and the road dust showed higher accumulation of the PTEs than the bulk samples. The contribution of the PM₁₀ fraction to the total amount of the pollutants in the bulk soil and road-dust samples accounted for 50–80%. The strongest contamination of the urban soils was found in the residential areas, while the road dust was mostly contaminated on the major highways.</p><h3 data-test=\"abstract-sub-heading\">Conclusion</h3><p>According to the results of the principal component analysis, most of the pollutants can be attributed to anthropogenic sources − non-exhaust and exhaust vehicle emissions. The other important sources of the PTEs are soil parent materials and the resuspension of soil particles. The contents of PTEs in the bulk soil and road-dust samples correspond to low and medium pollution levels. The elevated levels of the PTEs in the PM₁₀ fraction pose the greatest environmental hazard.</p>","PeriodicalId":17139,"journal":{"name":"Journal of Soils and Sediments","volume":"147 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"MMs (metals and metalloids) based 238U, 226Ra, 232Th,40 K contamination and health risk assessments in different surface soils near an uranium mine of Southeast China","authors":"Yanhe Guan, Zhongkui Zhou, Yadan Guo, Renyu Zeng, Jingying Chen, Zhanxue Sun","doi":"10.1007/s11368-024-03880-0","DOIUrl":"https://doi.org/10.1007/s11368-024-03880-0","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>The radionuclides pollution base on MMs (metals and metalloids) near uranium mines has been drawing broad attention, but the extent of their impact on soil and human health is still unclear. Therefore, the aim of this study was to investigate the distribution and health risk assessments of ²³⁸U, ²²⁶Ra, ²³²Th and ⁴⁰ K base on MMs (Cr, Ni, Cu, Zn, As, Cd, and Pb) in different surface soils near an uranium mine.</p><h3 data-test=\"abstract-sub-heading\">Materials and methods</h3><p>Surface soil samples were extracted from 35 representative sites near the Lefu uranium mine. Radionuclides and MMs were measured using high-purity germanium (HPGe) N-type coaxial detector and inductively coupled plasma mass spectrometer, respectively. Pollution status was evaluated using D_R, Ra_eq, AEDE, H_ext, and ELCR for radionuclides and P_i, I_geo, RI and health risk index for MMs. Their correlation was analyzed through Pearson/Spearman correlation analysis.</p><h3 data-test=\"abstract-sub-heading\">Results and discussion</h3><p>The average activity concentration of ²³⁸U, ²²⁶Ra, ²³²Th, and ⁴⁰ K are 504, 1227, 118, and 769 Bq·kg⁻¹ respectively and the average concentration of Cr, Ni, Cu, Zn, As, Cd, and Pb are 200, 33.9, 41.3, 132, 18.4, 0.26, and 78.7 mg·kg⁻¹, respectively. Values of D_R, Ra_eq, AEDE, H_ext, and ELCR all exceed the world average to varying degrees and values of P_i, I_geo, RI and the health risk index are within the acceptable ranges. Correlation analyses showed that ²³⁸U, ²²⁶Ra, ²³²Th and Pb are strongly correlated (correlation coefficient &gt; 0.6) with each other.</p><h3 data-test=\"abstract-sub-heading\">Conclusions</h3><p>On the basis of the obtained values, it can be concluded that generally higher radionuclides and MMs were distributed near the Lefu uranium. There are potential health risks associated with the elevated radioactivity. The overall situation of MMs is controllable, however, particular attention is warranted for Cr and Cd, as they approach values-at-risk. The strong correlations between ²³⁸U, ²²⁶Ra, ²³²Th and Pb imply a uniform pollution level or a possible shared source.</p>","PeriodicalId":17139,"journal":{"name":"Journal of Soils and Sediments","volume":"205 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sediment nitrate dissimilatory reduction processes in the river-lake ecotone of Poyang Lake, China: Mechanisms and environmental implications","authors":"Yinghui Jiang, Zhenglei Xie, Mingjun Ding, Hua Zhang, Gaoxiang Huang, Yun Cao, Guoyu Yin","doi":"10.1007/s11368-024-03890-y","DOIUrl":"https://doi.org/10.1007/s11368-024-03890-y","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>The river-lake ecotone in lake ecosystems can strongly influence sediment nitrate dissimilatory reduction processes. However, the mechanisms underlying these processes in river-lake ecotone ecosystems are still poorly understood. This study aims to investigate the rates of sediment nitrate dissimilatory reduction processes in Poyang Lake and clarify the mechanisms and environmental implications of these processes.</p><h3 data-test=\"abstract-sub-heading\">Materials and methods</h3><p>Sediment samples from five river-lake ecotones and lake ecosystems were collected from Poyang Lake, China. Sediment nitrate reduction and N₂O production rates were measured using ¹⁵N isotope tracing experiments. The abundance of denitrifiers, anammox 16S rRNA bacteria, and <i>nrfA</i> genes was quantified using the polymerase chain reaction method. Correlation analysis, redundancy analysis, and stepwise linear regression were used to evaluate the mechanisms of sediment nitrate reduction processes.</p><h3 data-test=\"abstract-sub-heading\">Results and discussion</h3><p>Sediments in the river-lake ecotone showed significantly higher denitrification (DEN), N₂O production, dissimilatory nitrate reduction to ammonium (DNRA), and anammox rates compared to lake ecosystems. DEN was the dominant process contributing to nitrate reduction, accounting for 73.36% and 74.13% in the river-lake ecotone and lake ecosystem, respectively. DEN, N₂O, and DNRA rates were significantly positively correlated with TOC, sulfide, and Fe²⁺ contents, which control the abundance of denitrifying and <i>nrfA</i> genes, ultimately increasing these rates.</p><h3 data-test=\"abstract-sub-heading\">Conclusion</h3><p>The annual input of reactive N to the lake from the watershed is almost equivalent to the annual N removal. However, higher DNRA and N₂O production rates indicate that approximately 23.59% of the annual N input to the lake may be transformed to NH₄⁺ or N₂O. N retention and N₂O production in the river-lake ecotone significantly exceed those in the lake ecosystem, highlighting the ecotone as a hotspot for eutrophication risk and N₂O emissions.</p>","PeriodicalId":17139,"journal":{"name":"Journal of Soils and Sediments","volume":"34 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}