Article
Engineering, Multidisciplinary
Adil A. M. Elhassan, Mohammed Mnzool, Hichem Smaoui, Abir Jendoubi, Bushra M. E. Elnaim, Maged Faihan Alotaibi
Summary: The impact of clay mineralogy on engineering properties, such as strength and stiffness, of road materials is investigated in this study. It is found that kaolinite is more effective than montmorillonite in reducing clay plasticity, and samples with high kaolinite content exhibit higher strength indicators. Additionally, kaolinitic soil samples have a larger constrained modulus than other samples.
ALEXANDRIA ENGINEERING JOURNAL
(2023)
Article
Environmental Sciences
Mu Su, Feiyu Han, Mengxiao Wang, Jingxuan Ma, Xuewei Wang, Zhijun Wang, Shuijin Hu, Zhen Li
Summary: The study revealed that high CEC montmorillonite clay minerals can adsorb more bacterial cells, thus providing a certain level of protection for microorganisms against Pb2+ stress. However, the addition of Enterobacter sp. actually increased the residual Pb2+ concentration in the solution by 7.5%, indicating that the adsorption of typical soil bacterium on clay minerals has a certain impact on the adsorption of Pb.
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
(2021)
Article
Forestry
Tiangang Tang, Peilei Hu, Wei Zhang, Dan Xiao, Li Tang, Jun Xiao, Jie Zhao, Kelin Wang
Summary: The stability of soil organic matter (SOM) is crucial for understanding soil carbon (C) dynamics under global warming. However, the influence of factors such as bedrock geochemistry, climate, and soil properties on SOM stability remains poorly understood. In this study, conducted in subtropical karst forests in southwest China, it was found that bedrock geochemistry, particularly the presence of calcium-rich bedrock, significantly influenced SOM stability by promoting the accumulation of exchangeable calcium and calcium carbonate in soils. High temperature also improved SOM stability by increasing the content and proportion of mineral-associated organic C (MAOC) and soil pH.
Article
Soil Science
Bowen Zhang, Minghua Zhou, Bo Zhu, Qianying Xiao, Xunhua Zheng, Jinbo Zhang, Christoph Mueller, Klaus Butterbach-Bahl
Summary: Soil physiochemical and biological properties play crucial roles in regulating nitrogen (N) transformation in soil, but the specific contributions of different soil properties remain uncertain. This study quantified the gross transformation rate of N in seven Regosolic soils in a subtropical montane agricultural landscape and identified the influences of microbial functional genes and soil properties on N transformation. The results showed that clay minerals and soil type also played important roles in regulating the rates of N transformation processes in Regosolic soils. Overall, these findings highlight the significance of clay minerals as mediators of gross N transformations in soil.
SOIL BIOLOGY & BIOCHEMISTRY
(2022)
Article
Soil Science
Anthony J. Mirabito, Lisa G. Chambers
Summary: By testing and modifying a standard method for quantifying mineral-associated organic matter (MAOM) in terrestrial soils, it was found that in wetland soils, particulate organic matter (POM) rather than MAOM is the main mechanism protecting soil organic carbon from mineralization. The study also revealed that the C to N ratio in wetland soils differs from that in terrestrial soils, which warrants further investigation in future research.
Article
Geosciences, Multidisciplinary
P. Lehmann, B. Leshchinsky, S. Gupta, B. B. Mirus, S. Bickel, N. Lu, D. Or
Summary: Clay minerals play a dominant role in soil colloidal fraction and specific surface area, with different types of clay minerals significantly influencing soil hydrological and mechanical behavior. Utilization of global maps of clay minerals allows for spatially resolved estimation of soil properties, leading to improvements in modeling water availability and erosion predictions on a global scale.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Environmental Sciences
Lori VandenEnden, Mark A. Anthony, Serita D. Frey, Myrna J. Simpson
Summary: Forest soils, acting as a carbon sink, are greatly affected by global environmental changes such as increasing temperatures and nitrogen deposition. The molecular composition of soil organic matter is altered by warming and nitrogen addition, impacting the decomposition process. Results suggest that the effects of nitrogen addition and warming on soil organic matter are not simply additive but interact in complex ways.
Article
Agronomy
Azamat Suleymanov, Ruslan Suleymanov, Vyacheslav Polyakov, Ekaterina Dorogaya, Evgeny Abakumov
Summary: This study investigated the influence of long-term conventional tillage on the water-physical, chemical properties, and composition of chernozems. The results showed that tillage deteriorated the water-physical properties of the soil and affected the organic matter composition. The study also found that long-term plowing decreased aliphatic structures and increased aromatic structures in soils. To improve soil fertility and carbon sequestration potential, it is important to implement conservation tillage practices and prevent degradation processes.
Article
Soil Science
Juan Li, Jinzhi Ding, Shanshan Yang, Liqing Zhao, Jiayi Li, Huangyu Huo, Miaoyue Wang, Jiayu Tan, Yingfang Cao, Shuai Ren, Yongqin Liu, Tao Wang
Summary: Soil carbon fixation has the potential to offset carbon emissions and mitigate climate change. The turnover time of soil carbon varies significantly across different regions and land cover types, with microbes and soil mineral protection being the key drivers.
SOIL BIOLOGY & BIOCHEMISTRY
(2023)
Article
Environmental Sciences
Kai Fang, Leiyi Chen, Shuqi Qin, Qiwen Zhang, Xuning Liu, Pengdong Chen, Yuanhe Yang
Summary: This study investigated the stability of soil organic matter in the Tibetan alpine permafrost region and found that SOM stability increased from the southeastern to northwestern plateau, with stronger stability associated with higher mineral-organic associations and more arid conditions. The study highlights the importance of considering mineral variables in Earth system models to better predict soil carbon dynamics across permafrost regions.
GLOBAL BIOGEOCHEMICAL CYCLES
(2021)
Article
Environmental Sciences
Bin Niu, Qiuyu Chen, Hongzhe Jiao, Xiaoqin Yang, Ming Shao, Jian Wang, Guicai Si, Tianzhu Lei, Yibo Yang, Gengxin Zhang, Georg Guggenberger
Summary: Mineral-associated organic matter (MAOM) is the largest soil carbon pool, but the understanding of different organo-mineral fractions and their response to environmental variables is limited. In this study, sequential chemical extraction was used to separate MAOM fractions and alpine forest soils were selected to assess their response to climate change. Residual and weakly adsorbed organic matter were the primary fractions, and climate indirectly affected their preservation through weathering and environmental factors. The organo-mineral fractions were closely associated with metal cations and secondary minerals, forming complex networks. Water-soluble, weakly adsorbed, and Fe/Al oxyhydroxide-stabilized organic matter played central roles in the networks and were related to soil pH, moisture, and microbial composition. Additionally, climate and weathering factors greatly impacted Fe/Al-OM complexes, oxyhydroxide-stabilized organic matter, and residual organic matter. The complex network among organo-mineral fractions provides insights into MAOM preservation under climate change.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Biodiversity Conservation
Laura Castaneda-Gomez, Kate Lajtha, Richard Bowden, Fathima Nahidha Mohammed Jauhar, Juan Jia, Xiaojuan Feng, Myrna J. Simpson
Summary: Forest ecosystems as global soil carbon reservoirs are affected by climate change factors that change carbon inputs. This study integrated molecular composition data sets of soil organic matter and microbial communities to investigate the effects of detrital input and removal treatments on forest soil carbon dynamics. The results showed that long-term litter additions did not increase soil carbon content, while litter reductions negatively impacted soil carbon concentrations. This highlights the sensitivity of soil carbon biogeochemistry to changes in litter deposition.
GLOBAL CHANGE BIOLOGY
(2023)
Article
Chemistry, Physical
Jiaqi Chang, Xiaodong Fan, Zhenxue Jiang, Xingmeng Wang, Lei Chen, Jitong Li, Lin Zhu, Chengxiang Wan, Zhixiang Chen
Summary: This study investigated the effects of organic matter, clay minerals and organo-clay composites on the pore structure and pore complexity of shale reservoirs. The results showed that the type and maturity of macerals, illite, kaolinite, and organo-clay composites are the main factors influencing shale pore development. The study also found that different clay mineral types have different effects on shale pore structure and pore complexity.
APPLIED CLAY SCIENCE
(2022)
Article
Agronomy
Lais Carvalho Vicente, Emanuela Forestieri Gama-Rodrigues, Seldon Aleixo, Antonio Carlos Gama-Rodrigues
Summary: Cacao-based agroforestry systems have the potential to sequester a significant amount of soil carbon, and the chemical composition of soil organic matter plays a role in the conversion of land use systems. Understanding the chemistry of soil organic matter can help guide management strategies and promote low-carbon agriculture in Brazil.
AGROFORESTRY SYSTEMS
(2023)
Article
Soil Science
Thiago M. Inagaki, Angela R. Possinger, Steffen A. Schweizer, Carsten W. Mueller, Carmen Hoeschen, Michael J. Zachman, Lena F. Kourkoutis, Ingrid Kogel-Knabner, Johannes Lehmann
Summary: The spatial distribution of organic substrates and microscale soil heterogeneity significantly influence organic matter (OM) persistence as constraints on OM accessibility to microorganisms. However, it is unclear how changes in OM spatial heterogeneity driven by factors such as soil depth affect the relative importance of substrate spatial distribution on OM persistence.
SOIL BIOLOGY & BIOCHEMISTRY
(2023)
Article
Chemistry, Analytical
Rajshree Ghosh Biswas, Ronald Soong, Paris Ning, Daniel Lane, Monica Bastawrous, Amy Jenne, Daniel Schmidig, Peter de Castro, Stephan Graf, Till Kuehn, Rainer Kuemmerle, Wolfgang Bermel, Falko Busse, Jochem Struppe, Myrna J. Simpson, Andre J. Simpson
Summary: Comprehensive multiphase-nuclear magnetic resonance (CMP-NMR) is a non-invasive approach that allows for the observation of all phases in intact samples. This technique is important for studying both dead and living organisms and understanding biological processes. A novel C-13-optimized E-Free magic angle spinning CMP probe was developed and tested for its effectiveness in ex vivo and in vivo samples. The probe showed promising results for detecting all phases in samples of varying biomass.
ANALYTICAL CHEMISTRY
(2022)
Article
Biodiversity Conservation
Laura Castaneda-Gomez, Kate Lajtha, Richard Bowden, Fathima Nahidha Mohammed Jauhar, Juan Jia, Xiaojuan Feng, Myrna J. Simpson
Summary: Forest ecosystems as global soil carbon reservoirs are affected by climate change factors that change carbon inputs. This study integrated molecular composition data sets of soil organic matter and microbial communities to investigate the effects of detrital input and removal treatments on forest soil carbon dynamics. The results showed that long-term litter additions did not increase soil carbon content, while litter reductions negatively impacted soil carbon concentrations. This highlights the sensitivity of soil carbon biogeochemistry to changes in litter deposition.
GLOBAL CHANGE BIOLOGY
(2023)
Article
Chemistry, Physical
Huan Tong, Mehran Behazin, Myrna J. Simpson
Summary: Bentonite clay is suggested as a buffer layer for Canada's geologic repository for long-term storage of nuclear fuels. The presence of natural organic matter (NOM) in bentonite may contribute to container corrosion. Molecular-level techniques were used to analyze bentonite composition under different heat and radiation conditions, and it was found that heat and radiation had minimal effects on overall NOM chemistry. Further research is needed to investigate longer exposure durations and overall stability of NOM in a deep geologic repository setting.
APPLIED CLAY SCIENCE
(2023)
Article
Environmental Sciences
Katherine L. Steeves, Meera J. Bissram, Sonya Kleywegt, Douglas Stevens, Frank L. Dorman, Andre J. Simpson, Myrna J. Simpson, Lindsay S. Cahill, Karl J. Jobst
Summary: This study discovered the presence of fluorotelomer ethoxylates (FTEO) in indoor dust and industrial effluent, indicating their potential as widespread and persistent pollutants.
ENVIRONMENT INTERNATIONAL
(2023)
Article
Environmental Sciences
Lisa M. Labine, Erico Oliveira A. Pereira, Sonya Kleywegt, Karl J. Jobst, Andre J. Simpson, Myrna J. Simpson
Summary: The study investigates the metabolic perturbations of PFAS on Daphnia, highlighting that different PFAS chain lengths and polar functional groups can induce unique metabolic responses while also sharing a common underlying toxic mode of action.
ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY
(2023)
Article
Environmental Sciences
Myrna J. Simpson
Summary: Soil pollution has had a global impact on ecosystem health, leading to a reduction in critical services provided by soil ecosystems. Environmental metabolomics has provided valuable insights into the effects of pollutants on soil-dwelling organisms, particularly earthworms. Recent studies have also explored the complex relationships between plants-microbes and earthworms-microbes, and how these relationships are altered by pollutant exposure in soil. Overall, these studies highlight the negative ecological cascade and decline in soil organism health caused by pollution.
CURRENT OPINION IN ENVIRONMENTAL SCIENCE & HEALTH
(2023)
Article
Marine & Freshwater Biology
Erico A. Oliveira Pereira, Lisa M. Labine, Sonya Kleywegt, Karl J. Jobst, Andre J. Simpson, Myrna J. Simpson
Summary: Phthalic acid esters (PAEs), commonly used as additives in plastics, can leach into the environment and cause various harmful effects on aquatic organisms. This study examined the impact of four phthalate pollutants on Daphnia magna using targeted metabolomic approach. Results showed unique metabolic profiles for each phthalate pollutant and disruption of amino acid and energy metabolism pathways. These findings suggest a common toxic mechanism of action for phthalate pollutants and emphasize the importance of targeted metabolomic approaches in understanding sub-lethal exposure to pollutants.
AQUATIC TOXICOLOGY
(2023)
Article
Biochemistry & Molecular Biology
Kiera Ronda, Katelyn Downey, Amy Jenne, Monica Bastawrous, William W. Wolff, Katrina Steiner, Daniel H. Lysak, Peter M. Costa, Myrna J. Simpson, Karl J. Jobst, Andre J. Simpson
Summary: Environmental metabolomics sheds light on the impact of human activities on organism health at the molecular level. This paper focuses on the use of in vivo NMR as a powerful tool for monitoring real-time changes in the metabolome of organisms. It also investigates the applicability of proton-only experiments on non-enriched samples, specifically using Daphnia as a model organism.
Article
Chemistry, Multidisciplinary
Iuliana Stoica, Maryam Tabatabaei Anaraki, Thomas Muratore, Melissa Knorr, Serita D. Frey, Myrna J. Simpson
Summary: By analyzing soil samples from the Harvard Forest Soil Warming and Nitrogen Addition experiment, this study found that increasing global temperatures and atmospheric nitrogen deposition threaten carbon storage in forest soils. The study emphasizes the importance of observing environmental stressors using molecular-level approaches to understand how anthropogenic activity will alter forest soil systems.
ACS EARTH AND SPACE CHEMISTRY
(2023)
Article
Biochemistry & Molecular Biology
Jessica C. D'eon, Brian P. Lankadurai, Andre J. Simpson, Eric J. Reiner, David G. Poirier, Greg C. Vanlerberghe, Myrna J. Simpson
Summary: Environmental metabolomics is an effective method for studying pollutant impacts on target organisms. Both NMR and MS-based methods are used for amino acid profiling in environmental metabolomic studies. In this study, we compared the quantification of amino acids in different model organisms using both H-1 NMR and LC-MS/MS methods. The results showed that both NMR and LC-MS/MS measurements were reliable for amino acid profiling, demonstrating the compatibility of these two analytical platforms in environmental metabolomics.
Article
Environmental Sciences
Istvan Fekete, Ornella Francioso, Myrna J. Simpson, Paola Gioacchini, Daniela Montecchio, Imre Berki, Norbert Moricz, Katalin Juhos, Aron Beni, Zsolt Kotroczo
Summary: Climate models predict warming and drying of Hungarian forests, raising concerns about their carbon storage capacity. To assess future changes, precipitation gradient studies were conducted on oak forests in Central Europe, investigating the quality parameters of soil organic matter (SOM). The results showed lower soil organic carbon (SOC) in humid forests due to increased decomposition and leaching of Ca, but the decrease in easily degradable SOM compounds. In dry forests, the amount of recalcitrant SOM increased, but so did the easily degradable SOM. Overall, SOC may increase in drier forests, partially offsetting the decrease in biomass.
Article
Reproductive Biology
Katherine C. Dibbon, Grace Mercer, Alexandre S. Maekawa, Jenna Hanrahan, Katherine L. Steeves, Lauren C. M. Ringer, Andre J. Simpson, Myrna J. Simpson, Ahmet A. Baschat, John C. Kingdom, Christopher K. Macgowan, John G. Sled, Karl J. Jobst, Lindsay S. Cahill
Summary: Maternal exposure to microplastics and nanoplastics during mouse pregnancy has been found to result in fetal growth restriction and placental dysfunction, with the effects being more pronounced in the group exposed to nanoplastics. This suggests that nanoplastic exposure during human pregnancy has the potential to disrupt fetal brain development and lead to suboptimal neurodevelopmental outcomes.
BIOLOGY OF REPRODUCTION
(2023)
Article
Environmental Sciences
L. M. Labine, E. A. Oliveira Pereira, S. Kleywegt, K. J. Jobst, A. J. Simpson, M. J. Simpson
Summary: Anthropogenic activities contribute to pollution in freshwater bodies worldwide, with wastewater treatment and industrial effluents containing complex mixtures of organic and inorganic pollutants. The molecular-level perturbations to the metabolic profile of Daphnia magna exposed to these effluents were examined in this study. The results showed significant metabolic changes, indicating oxidative stress, disruptions to energy metabolism, and protein dysregulation, highlighting the importance of metabolomics in assessing the interactions of industrial effluents.
ENVIRONMENTAL RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Katelyn Downey, Wolfgang Bermel, Ronald Soong, Daniel H. Lysak, Kiera Ronda, Katrina Steiner, Peter M. Costa, William W. Wolff, Venita Decker, Falko Busse, Benjamin Goerling, Agnes Haber, Myrna J. Simpson, Andre J. Simpson
Summary: Understanding environmental change requires molecular-level tools. This study investigates innovative experiments to improve low-field nuclear magnetic resonance (NMR) analysis of environmental and biological samples. Spectral simplification, selective detection, and heteronuclear NMR experiments were tested, and a novel selectively detected HSQC experiment was introduced. The results demonstrate the potential of low-field NMR in biological and environmental research, and its adaptability to various research needs.
MAGNETIC RESONANCE IN CHEMISTRY
(2023)
Article
Endocrinology & Metabolism
Grace V. Mercer, Nikita E. Harvey, Katherine L. Steeves, Celine M. Schneider, John G. Sled, Christopher K. Macgowan, Ahmet A. Baschat, John C. Kingdom, Andre J. Simpson, Myrna J. Simpson, Karl J. Jobst, Lindsay S. Cahill
Summary: Exposure to polystyrene nanoplastics during pregnancy caused abnormal fetal brain metabolism in mice, including decreased concentrations of gamma-aminobutyric acid, creatine, and glucose. The change in relative concentration of asparagine was dependent on fetal sex.