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This study investigated the most influential composting parameters (temperature, pH, humidity, C/N ratio, and CO2 emissions) on final compost quality. Composting bags (turned daily) containing prunings, lignocellulose material, cattle manure, and household organic waste were monitored for eight weeks across three batches. All the temperature data registered daily were statistically analyzed with one-way ANOVA to verify the consistency between batches. This study employs a first-order kinetic model to quantify the decomposition of organic matter in composting, revealing the influence of temperature on the decomposition rate. Principal component analysis was conducted for these factors and their interactions with respect to the final compost quality. Finished compost showed a significantly high nitrogen, phosphorus, and potassium content compared with that in the feedstock of the initial compost mixture, while there was constant organic carbon content. In addition to the control of key parameters, a linear regression analysis allowed us to identify the factors that most influenced temperature. We identified two key models: one including pH, humidity, C/N ratio, and CO2 emissions, and another focusing only on CO2. This study emphasized the importance of monitoring and controlling the crucial parameters of the composting process in order to obtain quality compost suitable for application in soil use. Moreover, high temperatures possibly attained in the process of aerobic decomposition destroy the pathogens, making the end products safer for uses in agriculture. [ABSTRACT FROM AUTHOR]

The productivity of olive in the northwestern coastal zone of Egypt is significantly constrained by drought and low organic matter in the soil. This study addresses these challenges by exploring the synergistic effects of olive mill wastes (OMW) application and micro-catchment water harvesting techniques on soil properties, runoff, moisture storage, and rainwater harvesting efficiency. Field experiments were conducted over two winter seasons, employing different micro-catchment structures (semi-circular and triangular bunds) and OMW applications. The results revealed that the integration of semi-circular bunds with OMW application (T4) substantially increased rainwater harvesting efficiency by 67.7% and 46.4% in the first and second seasons, respectively. Additionally, T4 and T5 exhibited reduced runoff by 47.8% and 41.3% in the first season and 49.4% and 38.9% in the second season, respectively. T4 significantly enhanced soil organic matter, soil macronutrients (N, P, and K), and micronutrients (Fe, Mn, Zn, and Cu) compared to the control (T1). The study highlights the effectiveness of T4 in improving soil moisture, reducing soil erosion, and enhancing soil fertility. This integrated approach involving OMW application within a semi-circular bund as a water harvesting system proves to be a promising strategy for sustainable olive cultivation in arid conditions. [ABSTRACT FROM AUTHOR]

When studying the carbon cycle in the biosphere, special attention is paid in Russia to the transformation of organic matter in the surface layer of supergene zone. The group composition of the organic matter (OM) in peats of different genesis in the taiga zone of Western Siberia is studied. Our data show that it is important to take into account the botanical composition of peat that make up natural and reclaimed forest swamps, well as their spatial heterogeneity, which is a necessary component when estimating the carbon stocks in peat soils of forest ecosystems within the national monitoring system for carbon pools and greenhouse gas fluxes. The experiments on peat OM transformation demonstrate that its efficiency is determined by its botanical composition. According to the rate of OM decomposition, the oligotrophic peats form a sequence: sphagnum–hollow > complex > fuscum > scheuchzeria–sphagnum > cotton grass–sphagnum > scheuchzeria > cotton grass peats and eutrophic peats: hypnum > sedge > sedge–hypnum > menyanthes > woody > wood–sedge peats. According to two-year field experiments on the transformation rate and direction of the OM of peat-forming plants, the component and chemical compositions of their OM significantly changes but in an individual manner for each plant. The content of aromatic polyconjugated systems and carboxyl groups increases, while the amount of carbohydrate fragments decreases. A 60 years long forest amelioration influences the transformation of peat OM. The degree of grass and sedge peat species in the process of amelioration increases by 5% in the 75-cm layer; the content of bitumens decreases, whereas the contents of easily hydrolyzable substances, humic acids, and lignin, increases. The microbiomes and enzymes of the peats in forest swamps of Western Siberian taiga are characterized. Our results confirm the hypothesis by V.E. Rakovsky that the differences in the species composition of peat-forming plants manifest themselves in the chemical and biological characteristics of peat. [ABSTRACT FROM AUTHOR]

A comprehensive study of the Mundrothruthu (MT) core (70 cm) from the Asthamudi wetland in Kollam, Kerala, India reveals three climate phases during the Little Ice Age (LIA) through multi-proxy investigations. The period (1507–1518 CE) shows high agricultural activity indicated by abundant diatom diversity, significant terrestrial influx, and freshwater runoff. Elevated TOC% and δ13C TOC values suggest high temperature and a warm, humid climate, likely driven by high terrestrial influx and transport of organic matter from the nearby surroundings. This may have increased the organic matter influx to the estuary leading to high TOC% and more negative δ1³C values. The second phase (1519–1548 CE) is characterized by increased marine incursion due to enhanced tidal currents, evidenced by a rise in marine palynomorphs, mixed terrestrial and marine organic matter, less negative δ13C values, and increased mud content. This shift likely reflects changes in sea level or tidal dynamics. The final period (1548–1804 CE) is marked by further enhancement of marine taxa, lower TOC%, and δ13C TOC values, indicating reduced atmospheric CO 2 and a temperature decrease of about 1 °C. This period is associated with reduced solar insolation and a southward shift of the Inter Tropical Convergence Zone (ITCZ). The study highlights both synchronous and asynchronous climatic behavior on the southwest coast of India relative to global changes during the LIA. Initially warm and humid with high agricultural productivity, the region gradually shifted to marine-dominated conditions due to tidal dynamics and broader climatic shifts. These findings underscore the complex interplay between local and global climatic factors during the LIA. [ABSTRACT FROM AUTHOR]

The application of hollow fiber membranes is one of the excellent processes to treat oily wastewater and wetland water. Treating oily wastewater and wetland water is a significant challenge and reported expensive. These wastes generally come from due the expansion of massive industries and human activities these days. This review discusses the critical ways of membrane hollow fiber application in treating oily wastewater as well as wetland water. It is also reported in literature that there is mostly organic contaminant accommodated in oily wastewater and wetland water. Due to that, the application of hollow fiber is the best way as a removal organic contaminant in oily wastewater as well as wetland water. Apart from that, the conventional and advanced methods are also well explained within this review followed by detail treatments, application, and performance of this hollow fiber membrane application. To achieve the best completed outcome of pollutants removal, several applications relate to other processes before contacting to hollow fiber membranes. The integration between conventional and advanced membrane technology in oily wastewater and wetland treatment is also well explained. The important factors in the fabrication and application of hollow fiber membrane depend on membrane materials and filtration processes. It means that the selection between membrane materials and final processes to choose are depending on the urgency, source of pollutants, and intended use. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agriculture & Nature / Kahramanmaraş Sütçü İmam Üniversitesi Tarım & Doğa Dergisi is the property of Kahramanmaras Sutcu Imam Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Forest management practices influence soil fertility and nutrient availability through different mechanisms. Despite the importance of soil fertility and nutrient availability in forest ecosystems, there is limited research on the effects of management practices on soil properties in mixed-species forests. This study investigates the impact of different management types (community forest area (CFA), Forest area (FR), and Sacred Grove (SG)) on soil physicochemical properties, organic matter, and organic carbon storage in Benue State, Nigeria. Soil samples from three forest management types were collected and analyzed using established laboratory standard procedures. Descriptive statistics, analysis of variance, and correlation analysis revealed significant differences (p<0.05) in soil texture, pH, organic carbon, and total nitrogen across the management types. CFA and FR were predominantly sandy loam soils, while SG had higher clay loam content. Soil pH ranged from 4.82 - 6.07 with SG having the highest pH value (6.07). The forest reserve has the highest sand content (75.0%) and SG has the highest clay content (34.6%). The highest soil organic matter content (3.13%) was recorded under CFA, while organic carbon of 1.83% was recorded under FR. The highest values of Mg (0.97 Cmol/kg), N (0.28%), P (3.77 ppm), K (0.20 Cmol/kg) Na (0.18 Cmol/kg), and Ca (1.24 Cmol/kg) were at their peak under the Sacred grove management types. Thus, the various types of forest management significantly impact soil properties and organic carbon content in the study area. It is recommended that SG or CFA management should be adopted for forest resource conservation in the study area. [ABSTRACT FROM AUTHOR]

Food waste (FW) is a valuable resource for anaerobic digestion (AD) due to its biochemical composition. This study aimed to optimize AD using two widely used optimization methods: Response Surface Methodology with Box–Behnken Design (RSM-BBD) and Taguchi orthogonal array L9. Organic load, oxidation–reduction potential, pH, and hydraulic retention time were evaluated for biogas production and volatile solids removal (VSr). The Taguchi method assessed responses based on the signal-to-noise ratio, resulting in optimal conditions for AD. After numerical optimization, the predicted biogas production was 440 mL, and VSr was 19.5%. However, the experimental observations of biogas production were 850 mL, and VSr was 41%. The RSM-BBD method, calculated based on analysis of variance, resulted in optimal conditions for AD, and after numerical optimization, the predicted biogas production was 852 mL, and VSr was 43%. However, the experimental observations of biogas production were 906 mL, and VSr was 44. Despite these results, the study found that Taguchi's design provided approximate optimization response values and did not allow parameter interaction. In contrast, RSM-BBD provided precise optimal values and details on the impact of individual and combined parameters, making RSM-BBD the preferred choice for optimizing AD systems for better prediction accuracy and reproducibility. [ABSTRACT FROM AUTHOR]

Both biotic and abiotic stress factors play an important role in reducing the growth and productivity of many crops. In this study, the effects of arbuscular mycorrhizal (AM) fungi and biochar (Bc) were investigated against Verticillium dahliae (Vd) disease in pepper plants grown under salt stress. These effects were evaluated on enzyme activities, salt tolerance, disease severity, plant growth and physiological characteristics. In this study, pepper was treated with 2% biochar, Funneliformis mosseae (Fm), Vd and different concentrations of salt (0 mM, 50 mM, 100 mM, 150 mM). The interaction of Fm and 2% Bc significantly increased the morphological parameters of the plant and the plant tolerated salt and Vd under combined high stress conditions of biotic (Vd) and abiotic (salt) stresses. It was also shown that Fm had a different effect than Bc on the membrane injury index (MII; %) and had a significant effect on leaf relative water content (LRWC; %). In addition, Vd increased mycorrhizal reliance, with the higher spore density of AMF higher disease severity observed in treatments involving Fm and Fm + Bc. Furthermore, phenol and antioxidant values were altered in Vd treatments, while Fm decreased CAT enzyme activation. Therefore, this study supports that AMF + biochar used in sustainable agriculture increases plant resistance to the soil pathogen (V. dahliae) and the salt stresses. [ABSTRACT FROM AUTHOR]

Woody debris (WD) stabilizes riverbeds, creates habitats, supports biodiversity, and enhances water quality in ecosystems. This study investigates the impact of WD on sediment characteristics and particulate organic matter (POM) accumulation in the Roztoka stream, located within a forested catchment in the Polish Carpathians. The focus is on the influence of different WD types: coarse (CWD, length > 1 m and diameter > 10 cm), fine (FWD, length < 1 m and diameter < 10 cm), and mixed (MWD, a combination of CWD and FWD) on sediment differentiation and POM accumulation. Stand age, ranging from 20 to over 120 years (in 20-year intervals), was also analyzed as a factor affecting WD structure and POM deposition. Results indicate that MWD had the greatest effect on sediment differentiation, with mean grain size (Mz) ranging from -3.91 phi to -0.95 phi. Stand age significantly influenced POM accumulation, with the highest content (19.51%) observed in age classes III and VI. Older stands (> 120 years) had a diminished effect on both WD structure and POM accumulation. This study underscores the critical role of WD in sediment differentiation and provides insights for improving the ecological function of natural streams. Although the findings are region-specific, they have broader implications for similar temperate mountainous forests. [ABSTRACT FROM AUTHOR]

Organic carbon (OC) burial in the Antarctic marginal seas is essential for regulating global climate, particularly due to its association with ice shelf retreat. Here, we analyzed total OC (TOC), total nitrogen (TN), radiocarbon isotope, n-alkanes and relative indicators in surface and core sediments from the Ross Sea, West Antarctica. Our aim was to investigate spatial and historical changes in OC sources, and to explore the influencing factors and implications for ice shelf retreat since the last glacial maximum (LGM). Our results revealed distinct spatial patterns of OC sources as indicated by n-alkane indicators in surface sediments. In the Western Ross Sea, n-alkanes predominantly originated from phytoplankton and bacteria, as evidenced by their unimodal distribution, low carbon preference index (CPI) of short-chain n-alkanes (CPIL = 1.41 ± 0.30), and low terrestrial/aquatic ratio (TAR = 0.22 ± 0.14). In the Southwest Ross Sea, n-alkanes were derived from marine algae and terrestrial bryophytes, indicated by bimodal distribution, low ratio of low/high molecular-weight n-alkanes (L/H = 0.62 ± 0.21), low CPI of long-chain n-alkanes (CPIH = 1.18 ± 0.16), and high TAR (1.26 ± 0.66). In contrast, the Eastern Ross Sea exhibited n-alkanes that were a combination of phytoplankton and dust from Antarctic soils and/or leaf waxes from mid-latitude higher plant, as suggested by both unimodal and bimodal distributions, high L/H (1.60 ± 0.58) and CPIH (2.04 ± 0.28), and medium TAR (0.61 ± 0.30). Geologically, during the LGM (27.3 -- 21.0 ka before present (BP)), there was an increased supply of terrestrial OC (TOC/TN = 13.63 ± 1.29, bimodal distribution of n-alkanes with main carbon peaks at nC17/nC19 and nC27). From 21.0 to 8.2 ka BP, as glaciers retreated and temperatures rose, the proportion of marine n-alkanes significantly increased (TOC/TN = 9.09 ± 1.82, bimodal distribution of n-alkanes with main carbon peaks at nC18/nC19 and nC25). From 8.2 ka BP to the present, as the ice shelf continued to retreat to its current position, the marine contribution became dominant (TOC/TN = 8.18 ± 0.51, unimodal distribution of n-alkanes with main carbon peak at nC17/nC18/nC19, and low TAR (0.41 ± 0.32)). This research has significant implications for understanding the variations in Antarctic OC sources and their climatic impacts in the context of accelerated glacier melting. [ABSTRACT FROM AUTHOR]

Accurate assessment of the mechanical properties of organic matter, clay matrix, and bulk shale during maturation remains a challenge. Here, we aim to assess the mechanical properties of organic-rich shale during maturation using a combination of nanoindentation methods and various geochemical analyses, i.e., mineral composition, mass loss rate, chemical structure of organic matter, and Rock-Eval analyses. Results show that the evolution of mechanical properties of organic matter in shale during maturation can be divided into: the main oil-generation stage, and the condensate oil and gas generation stage. The stiffening of organic matter in the shale is mainly due to increased aromaticity and condensation of aromatic groups. The clay matrix experiences a slight decrease in hardness and Young's modulus at low maturity levels due to the generation of liquid hydrocarbons. However, overall, the clay matrix becomes stiffer as the shale matures due to shale dehydration, expulsion or cracking of liquid hydrocarbons, transformation of clay minerals, and hardening of organic matter. The Young's modulus and hardness of bulk shale generally increase with increasing maturity. This is closely related to the hardening of organic matter and clay matrix, as well as the development of the more compact and dense microstructure in the shale. [ABSTRACT FROM AUTHOR]

ABSTRACT The interaction between humic acid (HA) and engineered nanoparticles (NPs) is critical in environmental sciences, especially for understanding the behavior of NPs in natural waters. This study employs 1H 2D Multi‐Exponential Transverse Relaxation (METR) NMR spectroscopy to examine the molecular‐level interactions between Pahokee Peat humic acid (HA) and carboxyl‐functionalized iron oxide nanoparticles (NPCOs). First, 1H 2D METR NMR spectroscopy allowed not only the identification of HA in terms of its chemical composition but also the separation of molecules with the same chemical shift values but different rates of molecular tumbling. Then, using solutions with varying NPCO concentrations (0, 10, 40, and 100 μM), we observed significant changes in the T2 relaxation times of HA components, indicating interactions between HA and NPCO. Analysis showed the biggest effect on two chemical shift regions, corresponding to lipids and carbohydrates, revealing that smaller molecules within these regions exhibit the most significant changes in T2 values upon the addition of NPCO. This suggests that these molecules are the initial sites of interaction, with the entire HA system being affected at higher NPCO concentrations. These findings highlight the utility of METR NMR spectroscopy in studying complex environmental mixtures and provide insights into the behavior of HA and NPs, essential for understanding the fate of NPs in the environment. [ABSTRACT FROM AUTHOR]

In this study, in addition to P, which is a bionutrient element for phytoplankton algae, during the deposition of bituminous claystones in the Ilgın area, the behavior of elements such as Cu, Ni, Zn, Cd, Ba and Se dissolved in water with organic matter was examined. In addition to nutrients such as N and P, elements such as Cu, Ni, Zn, Cd, Ba and Se act as nutritional elements in the biological productivity of phyto and zooplankton algae in lake and marine environments. The abundance of organic matter (%TOC) in bituminous claystones is closely related to bionutrient elements such as Cu, Ni, Zn, Cd, Ba and Se, which are bound to the organic structure as organometallic ligands, as well as P, which is an algal productive and bionutrient element in the water. In the analyzed samples, %TOC exhibits a very weak or weak correlation relationship with Cu (r=0.122), Ni (r=0.002), Zn (r=0.081), Cd (r= -0.279) and Ba (r= -0.661) respectively, while displaying a moderately strong correlation with Se (r= 0.685). This indicates that Selenium specifically exhibits an organophilic element. Moreover, in the examined examples; Cu shows very weak correlations with Fe (r= 0.220) and S (r=0.216), Ni shows weak correlations with Fe (r= 0.029) and S (r=-0.065), Zn demonstrates weak correlations with Fe (r= -0.142) and S (r= -0.135); Cd displays moderate correlations with Fe (r= 0.379) and S (r= 0.262); and Ba exhibits very weak correlations with S (r= - 0.515). Conversely, Se shows a strong correlation with Fe (r = 0.696) and S (r = 0.732), indicating that only Se is precipitated in the form of sulfide and sulfate compounds. Furthermore, in the analyzed examples; Cu displays a very weak correlation with Mn (r = -0.524) and Zn (r = -0.163), while Ba shows a strong correlation with Mn (r = 0.750). This suggests that Ba might have precipitated in the form of Barium Permanganate [Ba(Mn2O8)]. [ABSTRACT FROM AUTHOR]

Aims: The application of cover crop residue is an important means in managing paddy soil. This study was to investigate the influences of minerals on the mineralization of organic matter and the community and necromass of microbes in paddy soils amended with cover crop residue. Methods: 13C-labelled cover crop residue (Astragalus sinicus L.) was prepared using a pulse labeling method. The mineralization of cover crop residue and native soil organic matter and the community and necromass of microbes in two flooded paddy soils amended with or without illite, goethite and ferrihydrite was investigated by incubation experiments. The released CO2/CH4 was analyzed by gas chromatography. Amino sugar was used as the biomarker of microbial residue carbon. Soil microbial communities were analyzed by high-throughput sequencing and quantitative polymerase chain reaction. Results: Illite, goethite and ferrihydrite significantly decreased the amounts of both CO2 and CH4 emissions from native soil organic carbon in both paddy soils. Moreover, the inhibition efficiency followed the same sequence of ferrihydrite > goethite > illite for both CO2 and CH4 emissions. However, ferrihydrite significantly stimulated the mineralization of cover crop residue in both paddy soils. The examined minerals, especially ferrihydrite, also tended to decrease bacterial and fungal abundance and diversity in both paddy soils. Moreover, the contents of both bacterial and fungal residue carbon were significantly decreased by the examined minerals in alkaline paddy soil. Conclusion: Examined minerals tended to decrease total mineralization of cover crop residue and native organic matter, the microbial abundance, diversity, and necromass in flooded paddy soils. [ABSTRACT FROM AUTHOR]

Aims: Tree logging in tropical tree plantations results in significant soil disturbances that negatively impact soil biodiversity and soil functioning. Here, we aimed to assess the effects of adding organic matter (OM) to soil after rubber tree logging on soil functioning over time. Methods: The experiment was conducted in two contrasting soil types in Ivory Coast. Four practices were replicated, including a control with no residues, the presence of legumes only, legumes and all tree parts excluding the trunk, and legumes and all the parts of the tree including the trunk. We monitored the response of soil nematode communities every six months for 24 months in each practice. Samples were collected from the topsoil layer (0–10 cm) in the interrow, and we also monitored soil carbon transformation by measuring in situ basal soil respiration, labile soil carbon and organic matter decay using the bait lamina method. Results: The results showed a sharp decrease in nematode abundance after tree logging, but OM restoration increased nematode abundance, the relative abundance of bacterivores, and resource availability to the soil food web. The resilience of the nematode communities depended on soil conditions and the amount and quality of logging residues. Total nematode abundance was positively and significantly related to soil functioning, measured through basal soil respiration, labile soil carbon, and organic matter decay rate. Conclusion: The results suggest that restoring logging residues can be an effective way to restore soil biodiversity and mitigate the negative impact of clear-cutting in tropical rubber plantations. [ABSTRACT FROM AUTHOR]

Cambrian shales in China and elsewhere contain abundant oil and gas resources. However, due to its deep burial and limited outcrop, there has been relatively little research conducted on it. The Cambrian shale of the Tadong low uplift in the Tarim Basin of western China, specifically the Xidashan–Xishanbulake Formation (Fm.) and overlying Moheershan Fm. provide a case study through the use of organic petrology, mineralogy, organic and elemental geochemistry, with the aim of analyzing and exploring the hydrocarbon generation potential (PG) and organic matter (OM) enrichment mechanisms within these shale formations. The results indicate that: (1) the Cambrian shale of the Tadong low uplift exhibits relatively dispersed OM that consists of vitrinite‐like macerals and solid bitumen. These formations have a higher content of quartz and are primarily composed of silica‐based lithology; (2) shale samples from the Xidashan–Xishanbulake and Moheershan formations demonstrate high total organic carbon (TOC) and low pyrolytic hydrocarbon content (S2) content. The OM is predominantly type I and type II kerogens, indicating a high level of maturation in the wet gas period. These shales have undergone extensive hydrocarbon generation, showing characteristics of relatively poor PG; (3) the sedimentary environments of the Xidashan–Xishanbulake and Moheershan formations in the Tadong low uplift are similar. They were deposited in warm and humid climatic conditions, in oxygen‐deficient environments, with stable terrigenous inputs, high paleoproductivity, high paleosalinity, weak water‐holding capacity, and no significant hydrothermal activity; and (4) the relationship between TOC and the paleoproductivity parameter (P/Ti) is most significant in the Lower Cambrian Xidashan–Xishanbulake Fm., whereas correlation with other indicators is not evident. This suggests a productivity‐driven OM enrichment model, where input of land‐derived material was relatively small during the Middle Cambrian, and the ancient water exhibited lower salinity. A comprehensive pattern was formed under the combined control of paleoproductivity and preservation conditions. This study provides valuable guidance for oil and gas exploration in the Tarim Basin. [ABSTRACT FROM AUTHOR]

Fourier transform ion cyclotron resonance mass spectrometry of dissolved organic matter (DOM) extracted from environmental samples provides molecular speciation that enables visualization of compositional trends in the fate and cycling of biogenic and anthropogenic organics. Often, chemical contamination is introduced during field sampling (i.e., remote locations, cannot use glass). Further, preconcentration of DOM by solid-phase extraction often results in chemical contamination. When chemical noise is a dominant fraction of the ion signal, mass spectral performance is degraded by reduction of the ion trap analyte accumulation capacity and enhanced ion cloud dephasing during ICR detection. We have developed gas-phase ion depletion of unwanted chemical contaminants during ion injection into the linear RF ion trap of the hybrid linear ion trap 21 T FT-ICR mass spectrometer that improves detection of analytes by removing unwanted chemical noise. We demonstrate improvements in signal-to-noise ratio, dynamic range, and the number of observed analytes in dissolved organic matter samples that results in a 40–100% increase in the number of identified analytes. In many cases, the number of peaks observed per nominal mass more than doubles over select m/z regions. This gas-phase "clean-up" can salvage precious samples challenged by sampling location, sample volume, or collection protocols that cannot be avoided and maximizes the compositional information obtained. Further, this approach is generalizable and extendable to any hybrid linear ion trap instrument platform (e.g., LTQ-Orbitrap or linear ion trap-TOF). We highlight the power of gas-phase depletion with electrospray ionization, but this method is also applicable to other ionization modes. [ABSTRACT FROM AUTHOR]

Microbial biomass (MB) is an important indicator of soil quality, being responsive to changes resulting from soil management and use. Although there are studies that evaluate changes in soil microbiological attributes in coffee growing systems, the effects of these systems on MB and its relationship with other soil attributes have rarely been investigated, especially in tropical climate conditions at altitude. Therefore, this study aimed to evaluate the effect of different coffee growing systems on biomass and microbial activity and how these responses relate to other soil and litter attributes. Our study was carried out in soils under three Coffea arabica cultivation systems (CCM—monoculture, CCB—consortium with banana, AFS—agroforestry system with Grevillea robusta) and under native forest (NF). Soil samples were collected at a depth of 0–10 cm and subjected to analysis to determine the microbial biomass carbon content (MB-C) by the fumigation-extraction method, accumulated respiration through released CO2, soil organic carbon (SOC) and labile carbon by wet oxidation. There was a 45% reduction in SOC in coffee growing systems and a 75% reduction in MB-C in CCM compared to NF. The AFS is closer to native forest conditions due to its positive influence on the SOC content and the efficiency of converting this carbon into microbial carbon. The presence of the forestry component is positive and should be encouraged to mitigate the impacts of coffee growing on the soil. [ABSTRACT FROM AUTHOR]

In Unare and Píritu Coastal Lagoons, a study was carried out to assess the effect of C, N, and P load contributions on the capability of the sediments to immobilize phosphates. To achieve the later, the geochemical data of the sediments were coupled to the P‐sorption index of Bache and Williams (IBW). In both lagoons, the sediments showed a pH > 7 because of calcareous sedimentation. The inorganic carbon values in the lagoons displayed a spatial distribution with higher concentrations toward the shores, that is defined by the carbonate lithology. On the contrary, the inner part of the lagoons was characterized by the presence of organic materials associated to the clay. The phosphorus content in the Unare Lagoon ranged from 290 to 625 mg kg−1, whereas in the Píritu Lagoon the values fluctuated between 213 and 1013 mg kg−1. The highest concentrations of phosphorus in both lagoons could be linked to sewage and runoff input from agricultural and livestock activities around the lagoon systems. The IBW displayed adsorption average values of 21.97 and 27.42 for Unare and Píritu Lagoon, respectively, corresponding to a rather low P sorption. In Unare Lagoon, the IBW showed positive correlations with C, N and Felabile but negative with P. However, in the Píritu Lagoon, despite the analogous lithology of the lagoons, a slightly positive non‐significative correlation between IBW and IC was only found. Although the sediments adsorb P with a rather low capacity, they can mitigate the eutrophication process in the studied lagoons. [ABSTRACT FROM AUTHOR]

Turbidity flows are known to be affected by the density difference between sediment plumes and the surrounding water. However, besides density, other factors could lead to changes in flow propagation. Such a factor is the presence of suspended organic matter. Recently, it was found that flocculation does occur within plumes upon release of a sediment/organic matter mixture in a lock exchange flume. In the present study, mineral sediment (illite clay) was released into the outflow compartment containing water and synthetic organic matter (polyacrylamide flocculant). Even though the density of water was barely affected by the presence of flocculant, flow head velocity was observed to be larger in the presence of flocculant than without. Samples taken at different positions in the flume indicated that flocs were created during the small current propagation time (about 30–60 s) and that their sizes were larger with higher flocculant dosage. The size of flocs depended on their positions in the flow: flocs sampled in the body part of the flow were larger than the ones sampled at the bottom. All these properties are discussed as a function of sediment–flocculant interactions. [ABSTRACT FROM AUTHOR]

The sustainability of the primary sector is closely linked to meeting the demand for seeds using agro-industrial waste and bioresidues. Sustainability is a multidimensional concept focused on achieving environmental health, social justice, and economic viability. To this end, an experiment was designed based on a combination of biotechnological strategies accessible to many individuals. The first strategy involves the use of compost and vermicompost as cultivation substrates; the second is the in vitro acclimatization of potato plants to these substrates; and the third is the incorporation of Trichoderma asperellum into these substrates to determine the synergistic effect of both. The compost used in this work came from sewage sludge from an agri-food company (Cp); a dining room and pruning waste from a university campus (Cu); and vermicomposted coffee pulp waste (Cv). Each sample was mixed with coconut fiber (Fc) in proportions of 100, 75, 50, and 25%. In the resulting mixtures, María Bonita variety vitroplants were planted and placed in a greenhouse. The biometric response in the three cases indicated a dependence on the type of compost and the proportion of the coconut fiber mixture. The inoculation of Trichoderma asperellum with sewage sludge compost increased stem thickness (42.58%) and mini-tuber weight (6.74%). In contrast, uninoculated treatments showed the best performance in terms of the number of mini-tubers. A 50:50 mixture of sewage sludge compost with coconut fiber and without inoculation of Trichoderma asperellum was the best treatment for the production of pre-basic seeds of the María Bonita potato variety. The use of composted agricultural waste and bioresidues is shown as a valid and low-cost alternative for the sector, even independently of the incorporation of additional inoculants. [ABSTRACT FROM AUTHOR]

Copyright of Oilfield Chemistry is the property of Sichuan University, Oilfield Chemistry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fine particulate matter (PM 2.5) has been implicated in various health concerns. However, a comprehensive understanding of the specific PM 2.5 components affecting depression remains limited. This study conducted a Cox proportional-hazards model to assess the effect of PM 2.5 components on the incidence of depression based on the China Health and Retirement Longitudinal Study (CHARLS). Participants with 10-item Center for Epidemiologic Studies Depression Scale (CESD-10) score of 10 or higher were classified as exhibiting depression. Our findings demonstrated a significant positive correlation between long-term exposure to black carbon (BC), sulfate (SO 4 2−), and organic matter (OM) components of PM 2.5 and the prevalence of depression. Per 1 Interquartile Range (IQR) increment in 3-year average concentrations of BC, OM, and SO 4 2− were associated with the hazard ratio (HR) of 1.54 (95 % confidence intervals (CI): 1.44, 1.64), 1.24 (95% CI : 1.16, 1.34) and 1.25 (95% CI : 1.16, 1.35). Notably, females, younger individuals, those with lower educational levels, urban residents, individuals who were single, widowed, or divorced, and those living in multi-story houses exhibited heightened vulnerability to the adverse effects of PM 2.5 components on depression. Firstly, pollutant data is confined to subjects' fixed addresses, overlooking travel and international residence history. Secondly, the analysis only incorporates five fine particulate components, leaving room for further investigation into the remaining fine particulate components in future studies. This study provides robust evidence supporting the detrimental impact of PM 2.5 components on depression. The identification of specific vulnerable populations contributes to a deeper understanding of the underlying mechanisms involved in the relationship between PM 2.5 components and depression. • This study explore the association between PM 2.5 components and depression. • Black carbon, sulfate, and organic matter have significant impacts on depression. • Females, who living in multi-story house were susceptible to the PM 2.5 components. [ABSTRACT FROM AUTHOR]

The emerging field of biorefinery presents an opportunity to extract valuable resources from plant biomass like hemp, while tissue culture techniques, such as micropropagation, can produce uniform and high-quality plant material for biorefinery purposes. This study evaluated the use of hormonal and organic diets in creating callus from leaf fragments in three medical hemp cultivars over 8 weeks for biorefinery applications. The most effective treatment was the modified MS diet supplemented with 0.5 mg/L 2,4-D plus 0.5 mg/L KN, which induced callus formation in all three cultivars with an average size of 2.1 cm. Adding 150 mg/L of coconut water to the MS formula also showed significant results, inducing up to 50% callus formation in all three cultivars with an average size of 1.3 cm. Three different photoperiods were tested, with the 16:8 photoperiod being the most effective. White light was the most effective color, followed by blue light. The highest yield of extract was obtained from the callus section of Carmagnola hemp in the MS formula without growth regulators, with a yield of 2.75%. Consequently, this study provides valuable insights into the use of hormonal and organic diets, photoperiod, and light color for callus formation from leaf fragments in medical hemp, which could have important implications for producing high-value compounds via biorefinery processes. [ABSTRACT FROM AUTHOR]

The monitoring of carbon emissions is increasingly becoming a sustainability issue worldwide. Despite being largely unnoticed, the toxic gas carbon monoxide (CO) is ubiquitous in mechanized tunnel driving, but the individual sources, release and enrichment mechanisms are often unknown. In this study, the generation of CO from organic matter containing sedimentary rocks was investigated during mechanized tunnel driving and by reacting claystone and sandstone with 10 mM NaCl solutions for 2 months at 70 °C and 140 °C. The mineralogical and geochemical evolution of the solids and fluids was assessed by CO measurements and the XRD, DTA, TOC, IC and ICP-OES methods. The CO concentration in the atmosphere reached up to 1920 ppm (100 ppm on average) during tunnel driving, which is more than three times higher than the legal daily average dose for tunnellers, thus requiring occupational safety operations. Mineral-specific dissolution processes and the rapid decomposition of labile organic matter upon thermal alteration contributed to the liberation of CO and also carbon dioxide (CO2) from the host rocks. In mechanized tunnel driving, frictional heat and 'cold' combustion with temperatures reaching 50–70 °C at the drill head is an important mechanism for increased CO and CO2 generation, especially during drilling in sedimentary rocks containing significant amounts of OM and when the ventilation of the tunnel atmosphere and air mixing are limited. Under such conditions, human health damage due to CO exposure (HHDCO) can be 30 times higher compared to tunnel outlets, where CO is emitted from traffic. [ABSTRACT FROM AUTHOR]

In order to acknowledge the enrichment mechanism of organic matter in the black shale of the Middle Ordovician Yanxi Formation in central and southern Hunan area, the shale samples of the Yanxi Formation in the Maduqiao, Jinweixiang, Hejiadong and Mianhuaping are selected to test abundance of organic matter, major, trace and rare earth elements. The results show that the average total organic carbon (TOC) of black shale in study area is 2.03%, indicating the high abundance of organic matter in the Yanxi Formation. The CIA values and w(Sr)/w(Cu) ratios show that the Yanxi Formation had a warm and humid climate. The concentrations of Zn, V, Ni and Cu imply a medium primary productivity in the Yanxi Formation, whereas they have weak correlations with TOC. The element concentrations of V, Cr, Ni, and Mo reveal that the black shales were deposited in anoxic-euxinic conditions. The accumulation of organic matter is jointly affected by paleoclimate, primary productivity, redox conditions, sea level change and terrigenous debris. The organic matter enrichment model of the Yanxi Formation shales is a 'deepwater retention basin' controlleded by anoxic conditions. [ABSTRACT FROM AUTHOR]

The porosity and pore structure of mud shales are crucial for shale oil and gas storage and transportation. Although the change of organic matter state in thermal evolution has a significant effect on pore formation, the mechanism and main controlling factors still need to be deeply explored. In this paper, we selected the shale of the Yanchang Formation in the southeastern Ordos Basin as an object, and used low-pressure N2/CO2 adsorption, He density method, high-pressure mercury compression, and field FE-SEM to deeply investigate the relationship between thermal evolution and pore development in organic matter-rich shale. The experimental results show that FE-SEM observation reveals that the organic matter pores of the shale in the Long 7 section of the Extension Formation show four developmental states, in which the organic matter in the undeveloped pores is mainly of higher plant origin, solid asphalt and laminated organic matter. The organic matter with highly developed pores is nanofibrous, similar to extracellular polymers. Comparison of thermal simulation experiments shows that the high-pressure semi-closed system has stronger hydrocarbon drainage strength than the closed glass tube system. In the oil generation stage, the pore volume of both systems decreased, mainly due to oil filling; while the oil cracking stage was the main pore development period, especially in the high-pressure semi-closed system; Simulation experiments with different organic matter types and contents showed that the mud shale with better organic matter type and TOC content was more prone to hydrocarbon drainage and pore growth. Compared with type II/II mud shale, type I and II are more likely to form macropores, and compaction has an inhibitory effect on the formation of macropores. This study reveals the close relationship between the pore development of mud shale and its thermal evolution of organic matter, which provides an important reference for shale oil and gas exploration. [ABSTRACT FROM AUTHOR]

This article reviews a multiple signature lipid biomarkers and the origin of the standard methods, the different modified extraction techniques for extracting lipid biomarkers. Biomarkers are substances or collections of substances that can be used to identify particular species, groups of organisms, or environmental processes. Thus, lipid biomarkers may provide a powerful tool for reconstructing paleoenvironmental records, both as indicators of primary sedimentary source material and of alteration related to different geochemical and biochemical processes. Lipids are crucial components of organic matter (OM) and, in comparison to other OM constituents, are more resistant to post-depositional bacterial breakdown in marine sediments. Sea sediments are primarily composed of long-chain ketones, hydrocarbon, sterols and fatty acids synthesized by microalgae and bacteria, making microalgal organic matter easily identifiable. The ultimate source of marine sediment is telluric organic matter. The methods developed in connection with biomarkers are quantifiable, repeatable, and they offer important knowledge about every element in the aquatic environment. The predominant lipid biomarker is fatty acids is differentiated by change in its functional groups, of microorganisms be distinguished from the group attached to it. [ABSTRACT FROM AUTHOR]

Anthropogenic land cover change is directly responsible for the deforestation and degradation of tropical forests. In this context, assessing soil organic carbon (SOC) stocks is key to understanding the impact of anthropogenic activities on SOC so that we can implement management practices that effectively reduce emissions or promote carbon sequestration. Our objective was to assess the effect of land-use change on the dynamics and distribution of SOC in three systems (agriculture, pasture and agroforestry) after 40 years of deforestation in a tropical dry forest in the central–eastern region of Honduras. For this purpose, the bulk density, percentage of coarse fragments (>2 mm) and soil organic carbon content were determined at three depths (0.00–0.10 m, 0.10–0.20 m and 0.20–0.30 m). The results showed an increase in bulk density for all new uses, although soil compaction had not yet occurred. In terms of total soil organic carbon (TOC) stocks, deforestation caused a decrease from 17% to 48% in agricultural and agroforestry soils, respectively; on the other hand, grasslands did not show significant differences compared to tropical dry forest, suggesting that they have a high potential as carbon sinks in deforested tropical areas. However, this did not imply a better state of the system, as the greatest increases in bulk density were found in pastures. [ABSTRACT FROM AUTHOR]

Planting nitrogen-fixing plants in post-mining sites and similar degraded areas is a common approach to speed up soil development and buildup of the nitrogen pool in soil organic matter. The aim of this study was to explore if slower growth of alder seedlings in initial post-mining sites results from adverse soil conditions or lack of microbial symbionts. To address this question, we sampled young soil (age 15 years) and more developed soil (age 70 years) from heaps after coal mining near Sokolov (Czech Republic). Soil samples were sterilized and not inoculated or inoculated with arbuscular mycorrhizal fungi (AMF) or AMF + Frankia, followed by planting with alder (Alnus glutinosa) seedlings germinated and precultured under sterile conditions. The effect of soil age on alder growth appeared to be non-significant. The only significant growth effect was seen with Frankia inoculation, implicating this inoculum as a key factor in later succession in post-mining soils. When the soil was fully inoculated, alder biomass was higher in developed soil supplied with iron (Fe) and phosphorus (P), indicating that iron and phosphorus availability may affect alder growth. In young soil, alder growth was highest with a combination of iron, phosphorus, and sulfur (S), and a positive effect of sulfur in young soil may correspond with a reduced, alkaline soil pH and increased phosphorus and iron availability. [ABSTRACT FROM AUTHOR]

Agricultural residues are generated during the production and processing of agricultural crops. Under modern date palm plantation practices, field operations generate huge quantities of residues, which are discarded with little valorization. The date palm agro-industry produces significant amounts of waste. The accumulation of these residues can cause ecological damage to the oasis ecosystems. There is a lack of comprehensive data on long-term research studies that aim to assess the impact of date palm waste management practices. Composting and/or pyrolysis of date palm residues showed benefits for improving soil physical and chemical properties, particularly in sandy soils. This claim holds particular significance for arid and semi-arid regions, which are characterized by low fertility and are susceptible to soil degradation, accentuated by ongoing climate change. This review summarizes the existing literature concerning the valorization of date palm residues with regards to compost and pyrolysis processes, as well as the impact of their application on soil quality. Further research is required to assess the effects of using date palm residues for better soil amendment management. Research should focus on composting and biochar technologies for date palm residues and their application in arid and semi-arid regions to combat soil erosion and degradation. Increasing the beneficial uses of date palm residues could lead to sustainable and economic growth in dry areas. [ABSTRACT FROM AUTHOR]

Extensional tectonics along NE-trending faults, coupled with diapirism, created paleo-highs and subsiding basins, providing the structural framework for subsequent mineralization processes. The preservation of organic matter within the Fahdene and Bahloul Cretaceous formations during the Anoxic Oceanic Events (AOE-1 and AOQ-2) facilitated the extraction of metals from seawater. The association of metals with organic matter, Fe-Mg oxides, and pyrite is revealed by principal component analysis (PCA). The subsequent maturation of organic matter generated hydrocarbons, with thermal cracking leading to the incorporation of organo-metallic ligands into mobile hydrocarbons. Oilfield brines form as a byproduct of this catagenesis. The metal-rich hydrocarbons and basinal brines invaded SO4−2-rich fluids from Triassic evaporites, resulting in the precipitation of sulfates (barite and celestite) and the bacteriogenic (BSR) and/or thermal (TSR) reduction of sulfate to reduced sulfur, which combined with metals to form sulfide ores. This study examines the role of hydrocarbons in the genesis of ore deposits within the diapiric zone, drawing upon a synthesis of literature and geological data. It highlights the interplay between basinal evolution, the organic matter-rich Cretaceous formations (Fahdene and Bahloul), diapiric paleo-highs, and the Alpine orogeny, which are identified as crucial factors in ore genesis in the diapiric zone. [ABSTRACT FROM AUTHOR]

The near-coast environments where oysters occur are among the most impacted by humans globally, especially during the Late-Holocene. Yet, in West Africa, there is no documented historical record of change in these environments. We provide insight into the changing geochemical conditions of two oyster environments through high-resolution analysis of total organic carbon (C), total nitrogen (N), carbon and nitrogen isotope ratios (δ13C, δ15N), and trace elements, in two cores retrieved from the Densu estuary and the Anyanui (Keta) Creek in Ghana. Drastic shifts in sedimentation rate occurred in the Keta and Densu cores around 1996 CE and 960 CE respectively. At these times, comparatively, low levels of C and N were found in the Densu core. Increasing C and N levels and decreasing δ13C upcore aligned with the observed shift in sedimentation rate in the Keta core. The C/N ratios in the Keta core suggest allochthonous organic matter (OM) dominance in the creek. The Densu core showed periodic changes in C/N ratios from very high values (>20) between 1918 BCE and 1321 BCE, to values between 20 and 11 between 1321 BCE and 1977 CE and below 10 from the late 1970s CE to the present day, suggesting a varying degree of transformation in the catchment basin. Extremely high Sulfur (S) and moderate to significant Iron (Fe) increases suggest reducing conditions in the Keta sediments. Moderate Calcium (Ca), Zinc (Zn), and Strontium (Sr) concentrations in the upper part of the Densu core suggest a stronger influence of marine processes in the Densu in recent times. The findings reflect the impacts of catchment basin modification on the health of the two coastal environments, likely to impact the growth, productivity, and sustainability of the fishery of the West African mangrove Oyster. [ABSTRACT FROM AUTHOR]

Organic matter is the material basis of life, which is widely present in people's products and lives. The rapid and accurate detection of organic matter can be applied to the identification of fake and inferior products, the traceability of the origin of agricultural products, and the early warning of explosives in antiterrorism. By combining laser‐induced breakdown spectroscopy (LIBS) with argon, the spectral characteristics of five common organic compounds (nitroglycerin, metronidazole, polyformaldehyde, polypropylene, and phenolic resin), the plasma lifetime, the parameters of plasma thermodynamic state, and the distribution of three existing forms of the element C in two gas environments were compared, the influence of argon on organic LIBS results and the reasons for its enhancement were analyzed. The results indicate that argon makes the atomization of carbon chain structures in organic matter more complete, and reduce the interference of the element N in air on the organic LIBS results to a certain extent. The intensity differences of different organic substances are more obvious. support vector machine optimized by principal component analysis and particle swam optimization algorithm was used to classify five kinds of organic matter. The prediction accuracy of classification in air is 94.4%, and it improves to 100% in argon. This result provides a powerful method for high‐precision, real‐time in‐situ, and rapid identification of organic substances, which has important scientific significance for the study of organic substances LIBS. [ABSTRACT FROM AUTHOR]

Introduction: Overgrazing can have detrimental effects on the physical properties of soil in rangelands. Among the remedial methods for degraded soils, increasing rangeland fertility and striving to improve soil structure stability, reducing livestock trampling through grazing restrictions, are highlighted. Therefore, exclosure is one of the simplest remedial techniques, which involves preventing livestock access to all or part of a rangeland for one or more consecutive years. Thus, research on the effects of exclosure on the physical and chemical properties of soil in various regions helps determine the importance of this practice in different ecosystems. Based on existing studies, converting grazed lands into exclosures appears to be a suitable option for rehabilitating degraded soils. Establishing exclosures in degraded lands is an effective method for revitalizing degraded soils. This research examines how exclosures affect the physicochemical properties of degraded soils in the Sufikam rangelands in the northern part of Golestan Province. Material and Methods: In this study, soil samples were collected from 60 points in both degraded exclosure rangelands and natural rangelands. Subsequently, soil characteristics including organic matter, soil aggregate stability, electrical conductivity, acidity, SAR, ESP, and the percentage of clay, sand, and silt were measured. After determining and calculating the mentioned parameters, the normality of the data was assessed using the Shapiro-Wilk test. To compare the exclosures and natural rangeland, t-test and Wilcoxon were employed in the R environment. Results and Discussion: The results indicate differences in electrical conductivity, acidity, organic matter, particle stability, SAR, and ESP concentrations between the two study areas. The clay content in the exclosures area (25.19) was higher than in the natural (22.79), and the sand content in the natural rangeland (32.62) was significantly higher than in the exclosures (29.43). The clay content in the exclosure area has increased compared to the natural area, while the sand content in the natural area was significantly higher than in the exclosure area. The Pearson correlation between soil parameters in the exclosure area showed that the correlation between organic matter and soil aggregate stability (0.71), as well as between pH, EC, SAR, and ESP (0.84, 0.92) was positive. There was a negative correlation between organic matter and soil aggregate stability with pH (-0.93, -0.68), EC, SAR, and ESP (-0.25,-0.31). Conclusion: The use of exclosures can contribute to the stability of soil particles and improve land performance. Soil stability is a crucial feature in maintaining desirable agricultural practices and achieving sustainable land performance. This study demonstrates that the use of exclosures as a suitable and effective management practice can enhance rangeland health and improve the physicochemical properties of the soil. Therefore, it is essential to consider exclosure treatment as a key component in the design and implementation of natural resource management plans. The results of this study indicate that the implementation of grazing exclosure in rangelands leads to positive changes in soil properties and contributes to the increase in vegetation cover and the rehabilitation of the rangeland ecosystem. Therefore, grazing exclosure is presented as an effective management method for rehabilitating degraded soils. Implementing grazing exclosure programs alongside other corrective measures, such as planting suitable rangeland species, can increase soil stability and fertility and contribute to the natural vegetation restoration. Consequently, in rangeland management planning, the use of grazing exclosure as a suitable and cost-effective approach should be considered. [ABSTRACT FROM AUTHOR]

Copyright of Acta Scientiarum Naturalium Universitatis Pekinensis is the property of Editorial Office of Acta Scientiarum Naturalium Universitatis Pekinensis and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Most of the aquatic vegetation produces organic substances via the C3 photosynthetic pathway (mosses, isoetids—Lobelia dortmanna L., Luronium natans (L.) Raf., and vascular plants) or Crassulacean acid metabolism (CAM, e.g., Littorella uniflora (L.) Asch. and Isoëtes lacustris L.) or by their ability to use HCO3− via carbon concentration mechanisms (CCMs—some elodeids and charophytes). Differentiating these predominant photosynthetic pathways in aquatic vegetation based on their organic matter (OM) carbon stable isotopes (δ13CORG) is a complex task, in contrast to terrestrial plants. This study investigates the OM deposition, characterized by δ13CORG values in 10 macrophyte species with different photosynthetic pathways (C3, CAM, and CCM) collected from 14 softwater Lobelia lakes in northern Poland. The higher δ13CORG values distinguish the CCM group, indicating their use of 13C-enriched HCO3¯ in photosynthesis. CAM species show slightly higher δ13CORG values than C3, particularly in lower pH lakes. Principal component analysis of isotopic and environmental data did not yield clear distinctions by the groups, but still, they significantly differ in light of analyzed parameters and isotopic signals (PRMANOVA = 5.08, p < 0.01; K-W H = 27.01, p < 0.001). The first two PCA dimensions showed that the water pH and Ca2+ concentration positively influenced δ13C values. The influence of light conditions on δ13CORG values revealed by third PCA components seems to also be important. In summary, northern Polish Lobelia lakes serve as a key differentiation point between vegetation employing CCMs and those relying on C3/CAM photosynthesis without HCO3− utilization, providing insights into transitions in plant communities within these ecosystems. [ABSTRACT FROM AUTHOR]

Identification of potential lands on the basis of their environmental benefits and constraints can greatly contribute to the stability of canola production in different parts of the world including Sistan-Baluchestan province, Iran. Accordingly, using GIS, the scores of environmental factors affecting canola production including temperature, rainfall, slope, altitude, organic matter, soil salinity, pH and soil nutrients (N, P, K, Fe and Zn) were integrated along with the weights of analytical hierarchical process (AHP) for the production of canola suitability maps. The zoning maps of climate, topography, and soil as well as the canola suitability maps and the current production maps of canola were prepared. According to the AHP results canola cultivation was affected the most by climate (rainfall and water sources) compared with topography and soil. ArcGIS results indicated southern lands of Zahedan had the highest organic matter, and excluding Hirmand, other parts of the area had appropriate salinity for canola production. The most appropriate areas in terms of acidity for canola production are Hirmand and the central part of Zahedan. In arable soil, the nitrogen level was not maximum in the region, and Nimrooz and Zabol had the highest phosphorus. Potassium was average in the research area, and Zabol, Zahak, Nimrooz and Hamoon had the highest Fe. The output maps obtained from the combination of various ecological factors indicated that the moderate and non-suitable classes of land for canola cultivation are located in the northern parts of Zahak, Hamon, Nimzoz and the total lands of Hirmand and Zabol. [ABSTRACT FROM AUTHOR]

Historical sheep farming in the Patagonian drylands has led to reduced grass cover, soil erosion, and shrub encroachment, compromising ecosystem function. Effective restoration requires managing shrub cover, bare soil, and patch connectivity through various strategies. This study evaluates rehabilitation interventions in a grass-steppe ecosystem, comparing grazed and ungrazed areas. Over three years, we tested the following: (a) mechanical shrub cutting with biomass redistribution, and (b) enhancing patch connectivity with Pinus spp. branch piles, alongside controls, in eighteen 5 m × 5 m plots invaded by Mulinum spinosum. Half of the plots were fenced to exclude grazing, resulting in six treatment combinations. We monitored soil properties, vegetation cover, and species composition. The treatments explained twice as much of the variation in community composition as the annual climatic variations (0.26 vs. 0.13). Livestock exclusion increased perennial grass cover more than the grazed plots did (2.14 vs. 1.42 times the initial measure). All treatments reduced the amount of bare soil except the grazed controls. Shrub cutting, especially with grazing, increased the lasting litter coverage by 5–10% and decreased the bare soil equivalently. Organic matter increased except in the non-intervened interpatches (0.95 times). The enclosures with cut shrubs trapped erodible particles, showing a 5% increase. Our study highlights that grazing destabilizes communities, while enclosures stabilize them, with interventions improving soil fertility and mitigating erosion. [ABSTRACT FROM AUTHOR]

This study aims to investigate the effects of manure and vermicompost in terms of soil elasticity modulus changes in loam soil. The uniaxial compression test measures the compressive strength of a soil cylinder without any lateral load. The modulus of elasticity was determined by plotting the strain-stress diagrams and calculating the slope of these diagrams. The increase in moisture and organic matter content significantly improved soil flexibility and decreased its elasticity modulus. It was found that adding animal manure had a greater effect on the flexibility of the soil as compared to vermicompost, while the elasticity modulus of the samples containing animal manure was lower. The interaction effect of moisture and the organic matter content indicated that the increase in humidity was more effective in the soil containing vermicompost as compared to the soil containing manure, such that when the manure rate was around 19%, the moisture increase had no significant impact on the elasticity modulus. It was found that adding organic matter was more effective at the low moisture level of 15.5% than at higher moistures where the effect of adding organic matter did not affect the soil elasticity modulus decrement as strongly. [ABSTRACT FROM AUTHOR]

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study characterises the effects of naturally varying organic content on the compression and shear behaviour of a marine silty-clay from the Netherlands. Index properties and mechanical properties are determined through laboratory tests, including oedometer and multistage loading-unloading triaxial stress paths. The results indicate a significant impact of the organic content on the compression response, with both the loading and reloading indexes increasing as the loss on ignition increases from 3% to 7%. Additionally, the study suggests a directional response of the compression behaviour, with the loading index increasing with the stress ratio. The influence of the organic content on shear strength appears to be less significant. No brittle response is observed during shearing, and a similar ultimate stress ratio is attained by all samples. However, a unique critical state line can only be identified for samples with similar organic content, as its intercept and slope are found to increase with increasing organic content. The experimental results from stress paths at constant stress ratio reveal an anisotropic pre-failure plastic deformation mode, which depends on the previous stress history and loading direction. This suggests that the stress–dilatancy relationship cannot be formulated as a unique function of the stress ratio. The high-quality experimental data presented in the study enlarge the database on soft organic soils in view of the development of advanced constitutive models. [ABSTRACT FROM AUTHOR]

Abstract The significance of suspended sediment in the context of nutrient cycling and distribution in reservoirs is rarely reported in the scientific literature. What’s more, suspended sediment (SS) have so far not been taken into account as a potential factor amplifying the degrading effects of nutrients on the functioning of reservoirs. In the experiment described here, the variability of SS concentrations and the content of total nitrogen (TN), total phosphorus (TP), total organic carbon (TOC) and organic matter (OM) were investigated to determine the potential and determinants of SS in the process of migration of these substances at the water-sediment interface in retention reservoirs. The results showed that SS significantly manipulate the distribution of values of total phosphorus and total organic carbon contained in bottom sediment. It was confirmed that the circulation and distribution of selected nutrients in reservoirs is closely related to suspended sediment. Thus, it was proven that SS significantly affect the quality of deposited sediment. Finally, it was concluded that suspended sediment in the water of reservoirs forms a kind of micro-ecosystem, in which it plays a hitherto undiscovered role of a catenary (hub) consolidating a number of phenomena and processes occurring between individual components in the water-bottom sediment system.

Abstract Accurate assessment of the mechanical properties of organic matter, clay matrix, and bulk shale during maturation remains a challenge. Here, we aim to assess the mechanical properties of organic-rich shale during maturation using a combination of nanoindentation methods and various geochemical analyses, i.e., mineral composition, mass loss rate, chemical structure of organic matter, and Rock-Eval analyses. Results show that the evolution of mechanical properties of organic matter in shale during maturation can be divided into: the main oil-generation stage, and the condensate oil and gas generation stage. The stiffening of organic matter in the shale is mainly due to increased aromaticity and condensation of aromatic groups. The clay matrix experiences a slight decrease in hardness and Young’s modulus at low maturity levels due to the generation of liquid hydrocarbons. However, overall, the clay matrix becomes stiffer as the shale matures due to shale dehydration, expulsion or cracking of liquid hydrocarbons, transformation of clay minerals, and hardening of organic matter. The Young’s modulus and hardness of bulk shale generally increase with increasing maturity. This is closely related to the hardening of organic matter and clay matrix, as well as the development of the more compact and dense microstructure in the shale.

Isotopic studies are currently among the most prioritized methods for addressing critical challenges in petroleum geology, particularly in determining the nature and sources of organic matter. This paper briefly presents the results of utilizing isotopic markers in addressing issues related to: stratigraphic correlation, geochemical characterization of organic matter, and fluid dynamic reconstruction. The isotopic effects (δ18О, δ13С) observed in the study of Meso-Cenozoic sections in Crimea and the Western Pre-Caucasus have enabled the identification of global events, facilitating detailed stratigraphic correlation. Analysis of the isotopic-geochemical characteristics (δ13С) of fluids from sedimentary formations of varying ages allowed for the determination of formation conditions, the genesis of organic matter, and its geochemical classification for a group of fields at Kamennaya Vershina (Western Siberia). By integrating geochemical vertical zonality, evidence of hydrocarbon mixing from different origins, and the detection of localized thermal anomalies based on isotopic parameters, a comprehensive fluid dynamic model was developed, incorporating previously acquired geological and geophysical data.

Recent research has revealed the patterns of spatial and temporal variability of crop yields for the Polissia and the Forest-Steppe regions of Ukraine. In addition, the approaches to differentiating agroeconomic and agroecological components in the variability of the productive potential of the territories were developed. Approaches have been developed to quantify the spatial and temporal variability of soil erosion for individual areas of the region. The issue of assessing the impact of erosion processes on crop yields at the regional level remains unresolved. The diversity of landscapes and soil cover in Polissia and the Forest-Steppe of Ukraine was assessed in this article. The research covered 10 administrative regions of the north and northwest of Ukraine, which are located mainly within mixed forests (Polissia) and the eastern European forest steppe (Forest-Steppe). Part of the territory is tangential to the Carpathian mountain forests and the Pontic steppe. Within the study area, 30 WRB soils were identified. The largest area is occupied by Phaeozems Albic (21.7% of the total area of the region). These soils are located mainly in the southern and central parts of the region. In the north of the region, Phaeozems Albic form an almost continuous cover, and to the north, the areas of these soils become island-like. Phaeozems Luvic cover 12.1% of the region's territory. The Phaeozems group also includes Phaeozems Gleyic (0.93%), Phaeozems Haplic (0.13%), and Phaeozems Sodic (1.78%). Albeluvisols Umbric (17.1%) occupy a significant part of the region's territory. These soils occupy the north of the region and extend south along the Dnipro River floodplain. Spatially close to these soils are Albeluvisols Gleyic (12.8%). In the western part of the region, in Prykarpattia, there are Albeluvisols Stagnic (0.82%). The organic carbon content in the soils of the administrative districts of the region in the 0-5 cm layer was 5.2±3.3% and ranged 0.5% to 23.9%. In the layers of 5–15 and 15–30 cm, this figure decreased to 1.9 ± 1.1% and 1.9 ± 1.0%, respectively. In the 30–60 cm layer, the organic carbon content was 1.4 ± 0.8% and ranged 0.1% to 6.1%. The lowest organic carbon content was observed in the north central part of the region, and the highest content was observed in the north-east and north-west of the region. In the south of the region, there was found a strip of soils with moderate organic carbon content. The lowest content of organic carbon is characteristic of Albeluvisols and Podzols, which are located in the north of the region. In turn, the highest content of organic carbon is characteristic of organogenic Histosols, which, together with Albeluvisols and Podzols, form the basis of the soil cover structure of the territories in the northeast and northwest of the region. It should be noted that the agronomic role of these soils is insignificant, and their organic carbon content cannot be considered as a traditional indicator of fertility. Nevertheless, organic carbon is a reliable indicator of the anti-erosion properties of both natural and agricultural soils. The organic carbon content of Chernozems is quite high, which is a factor in the high fertility of these soils and their importance in agricultural production. The organic carbon content of Fluvisols and Gleysols is naturally high. The importance of these hydromorphic soils is due to their high productive potential, which ensures their use in agriculture. It is also worth noting their high seed protection potential. Phaeozems cover a large area of the region and contain a high level of organic carbon. These soils form the basis of agricultural production and forestry in the region. The silt content in the region's soils measured 45.6 ± 8.5%, ranging 19.1% to 57.6%. The north of the region is represented by soils with the lowest silt content (19–41%). In the center, in the west of the region, there is a zone with the highest silt content (53–58%). In other parts of the region, there are transitional levels of silt content in the soil. The clay content in the soils was 30.7 ± 13.8% and ranged 7.4% to 36.0%. The zone with the lowest clay content in soils has been formed in the north. The highest clay content in soils is typical for the southern part in the center of the region. The sand content in soils is highest in the northern part of the region, and the lowest in the southwestern and southern parts of the region.

Historical sheep farming in the Patagonian drylands has led to reduced grass cover, soil erosion, and shrub encroachment, compromising ecosystem function. Effective restoration requires managing shrub cover, bare soil, and patch connectivity through various strategies. This study evaluates rehabilitation interventions in a grass-steppe ecosystem, comparing grazed and ungrazed areas. Over three years, we tested the following: (a) mechanical shrub cutting with biomass redistribution, and (b) enhancing patch connectivity with Pinus spp. branch piles, alongside controls, in eighteen 5 m × 5 m plots invaded by Mulinum spinosum. Half of the plots were fenced to exclude grazing, resulting in six treatment combinations. We monitored soil properties, vegetation cover, and species composition. The treatments explained twice as much of the variation in community composition as the annual climatic variations (0.26 vs. 0.13). Livestock exclusion increased perennial grass cover more than the grazed plots did (2.14 vs. 1.42 times the initial measure). All treatments reduced the amount of bare soil except the grazed controls. Shrub cutting, especially with grazing, increased the lasting litter coverage by 5–10% and decreased the bare soil equivalently. Organic matter increased except in the non-intervened interpatches (0.95 times). The enclosures with cut shrubs trapped erodible particles, showing a 5% increase. Our study highlights that grazing destabilizes communities, while enclosures stabilize them, with interventions improving soil fertility and mitigating erosion.

Abstract Our study helps to unravel the complexity of the Lomagundi–Jatuli event, the largest and longest positive carbon isotope excursion ever recorded on the Earth’s surface, by providing a unique view of Paleoproterozoic graphitic rocks from the Borborema province of Northeastern Brazil. Through detailed mineralogical, textural, chemical and isotopic analyses, we bring a new perspective that provide support to elevated primary productivity and large-scale organic carbon burial during the Lomagundi–Jatuli event. Graphite crystals with distinctive textural features occur in association with silicate and oxidised manganese ores, manganese quartzites, garnetites, and gneisses. The graphites were crystallised at temperatures up to 634 °C, consistent with amphibolite facies metamorphism, according to Raman thermometry. An average total carbon content of 2.1 wt%, with δ13C values ranging from − 15.0 to − 21.5‰, is indicated by whole-rock geochemistry and carbon isotopic composition, respectively. Based on these results, our study proposes that these graphitic rocks may represent remnants of organic matter, possibly derived from bacterial biomass associated with manganese-rich sediments, preserved under reducing environmental conditions in a redox-stratified marine setting. Biological mediation on the origin of silicates is suggested by the close relationship between reduced manganese silicates and graphite. These constraints indicate that Paleoproterozoic graphite-rich rocks represent an important but overlooked reservoir of organic carbon that was partially degassed during the metamorphism of organic-rich sequences. Overall, this research provides new insights for the enigmatic emergence of the Lomagundi–Jatuli event, highlighting the intricate interplay among organic carbon, manganese-rich rocks and Earth's evolutionary processes during this period.