Secondary organic aerosols (SOAs) formed via the photooxidation of toluene and other aromatics are major components of fine particles. A synchrotron radiation vacuum ultraviolet photoionization aerosol mass spectrometer (VUV-PIAMS) was used to conduct online detection of the components of SOA generated by toluene chamber simulation in this study. Mass spectra of SOA particles were measured at a photon energy of 10.5 eV. The photoionization efficiency (PIE) curve of each ion peak within the 7.5-11.5 eV range was obtained, and then the qualitative analysis based on ionization potential (IP) was utilized to determine the composition of SOA. Experimental results demonstrated that mass spectra of toluene SOA primarily contained peaks at m/z = 64, 72, 94, 106, 108, and 122, with IPs of 8.92±0.03, 9.63±0.03, 8.53±0.03, 9.45±0.03, 8.28±0.03, 8.93±0.03, and 9.26±0.03 eV, respectively. Combined with theoretical calculations and offline measurements of ultraviolet-visible absorption spectroscopy and electrospray ionization mass spectrometry, it was determined that furan, methylglyoxal, phenol, benzaldehyde, 2-methylphenol, 4-methylphenol, and benzoic acid were the major components of toluene SOA. Based on the areas of the mass peaks, methylphenol, benzaldehyde, benzoic acid, methylglyoxal, phenol, furan, and unidentified components accounted for 21.4%, 17.1%, 15.7%, 14.3%, 12.9%, 11.4% and 7.2% of the measured components, respectively. The obtained results provide new information for studying the photooxidation mechanism of toluene. VUV-PIAMS overcomes cumbersome sample preparation procedures, potential secondary contamination, and other shortcomings of offline measurements, making it a useful tool for measuring the compositions of SOA and revealing their formation processes.
Environmental conditions significantly affect greenhouse gas (GHG) emissions from rice paddies. Using an open-path monitoring system, this study investigated methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O) emissions from intermittently irrigated coastal rice fields in northern Zhejiang, China. The results revealed synchronized trends in air, soil, and rice canopy temperatures, all peaking at the late tillering stage. Gross primary production (GPP) and net ecosystem production (NEP) showed similar dynamics, with cumulative values of 850.51 and 294.36 g C/m2, respectively. Both GPP and NEP showed linear positive correlations with photosynthetically active radiation (PAR) and a quadratic relationship with vapor pressure deficit (VPD). CH4 emissions peaked at tillering, with daily fluxes of 0.02-1.19 g/m2/d and a total of 27.05 g/m2. Positive linear correlations were observed between CH4 emissions and temperature as well as VPD, explaining 15.12-17.37% and 10.14% of CH4 variation, respectively. The average N2O flux was 2.5281 μg·m-2·h-1, with higher cumulative fluxes during the jointing and booting stages. These results clarify GHG emission characteristics in northern Zhejiang’s rice fields and support the development of mitigation strategies.
The microbial succession in activated sludge for the treatment of oily wastewater from ships was investigated by high-throughput sequencing of the 16s rRNA gene, and the microbial metabolic pathways of sulphur were determined. Proteobacteria was the dominant phylum, with a relative abundance of 57.2%-88.0%, and Thiobios and Thiobacillus played an important role in the associated sulphur metabolism. Diversity and species differentiation analyses showed that sample A4 after 1 year of domestication had the lowest species diversity. The species with large differences were Thiobios, SM1A02, Thiobacillus, and Flavobacterium. Sulphite oxidation to sulphate occurs through the sulphite oxidase (SO) pathway. Sulphur-oxidising bacteria such as Thiobios and Thiobacillus convert sulphite into sulphate through the SO pathway using sulphite-oxidising enzymes. In addition, the sulphite dehydrogenase and reverse heterogeneous sulphate reduction pathways were predicted. These pathways may jointly participate in and regulate the sulphur cycle during the treatment process of oily wastewater from ships. This paper systematically reveals the succession patterns of functional microorganisms in the biological treatment of oily wastewater from ships and the key sulphur metabolic pathways, providing a microbiological basis for optimising the biological treatment process of oily wastewater from ships and enhancing the efficiency of sulphur metabolism.
Anthropogenic geomorphology focuses on the study of man-made landforms and the processes that contributed to their creation. It also examines the processes that impact these relief forms in the landscape after the activities that formed them have ceased. The original natural structure of the landscape was significantly shaped by human activities. The Central Spiš region has suffered significant damage due to mining and industrial activities. Following the decline of mining, the abandoned mining and industrial sites in this area were left to the natural processes of recovery. However, natural forces have not been enough for this, and so the region has remained without a chance to attract investors and achieve ecological stability. Localities and objects related to mining and industrial activity today represent environmental burdens in the original natural landscape. They need to be eliminated as soon as possible for the greening of the landscape and the health of its inhabitants. The main research problem is the unknown state of abandoned anthropogenic landforms, their unknown composition, and the lack of information for landscape management with the aim of restoration. The aim is to obtain detailed information about the opening and dimensions of the largest anthropogenic landforms in the region, their heavy metal content, and the potential danger they may pose. In conclusion, we present the possibilities of environmental protection. The studied anthropogenic landforms have proven to be significantly different and require a differentiated approach to solving the issue of restoration of a man-made landscape.
Rapid urbanization has profoundly altered environmental conditions, presenting new challenges to forensic entomology by influencing key insect evidence used to estimate the postmortem interval (PMI). This study examined the impact of building height on necrophagous insect activity, diversity, and succession in Kafrelsheikh, Egypt. Guinea pig carcasses were placed at three height levels ‒ ground level (L1, 0 m), intermediate (L2, 20 m), and high-rise (L3, 50 m) ‒ and monitored for decomposition and insect colonization. Decomposition rates remained consistent across all heights, whereas insect density and diversity significantly declined with increasing elevation (e.g., mean insect abundance dropped from 84.59±6.12 at L1 to 15.85±3.14 at L3, and the Shannon diversity index from 2.7±0.08 to 2.2±0.12), likely due to stronger air currents, greater temperature variability, and limited accessibility at higher levels. Early colonizers, including Musca domestica and Sarcophaga argyrostoma, showed delayed arrival of one to several days or were completely absent at elevated sites, accompanied by notable shifts in species composition and succession timing. Statistical analyses (one-way ANOVA: F(2,15) = 68.21, p<0.001, η² = 0.76; Kaplan–Meier log-rank test) confirmed significant elevation-dependent differences in insect activity. These findings highlight the need for height-adjusted PMI estimation models in urban forensic investigations, particularly in high-rise environments.
Long-term differentiation in ecological resilience within ecologically livable villages remains insufficiently understood under rapid urbanization and persistent land-use change. Using a regionalscale sample of 1,090 ecologically livable villages in the Yangtze River Delta, this study constructed an ecological resilience index (ERI) and its three dimensions ‒ resistance, adaptability, and recovery ‒ and identified spatial patterns and temporal trends in 2003, 2008, 2013, 2018, and 2023. The 1,090-village sample was used as the main regional-scale sample to identify long-term ERI patterns and regional background explanatory variables, whereas the 107-village corridor sample was introduced as a supplementary mechanism sample to examine local spatial configuration factors under a relatively similar Yangtze corridor context. We then applied XGBoost-SHAP to characterize variable importance, SHAP contribution directions, and nonlinear response ranges in the regional-scale and corridor-level analyses. ERI remained broadly stable from 2003 to 2023, but spatial differentiation persisted. Runoff, cropland proportion, and precipitation were the dominant explanatory variables associated with ERI in 2023. In the corridor sample, road density, POI density, and road length showed higher explanatory power than other local mechanism variables. These findings show that persistent differentiation was jointly associated with long-term regional patterns, regional background conditions, and local environmental and spatial configuration factors, and they provide an empirical basis for environmental assessment, spatial configuration optimization, and differentiated management in ecologically livable villages.
Accurate knowledge of the distribution patterns and environmental determinants of threatened plants is essential for effective conservation prioritization. We conducted a regional assessment of nationally protected gymnosperms in Guangxi, southern China, a karst-dominated region spanning tropical– subtropical climatic transitions. Based on 213 georeferenced records for 35 taxa (6 families, 15 genera), we examined species richness, elevational patterns, and climatic associations at a regional scale across Guangxi (using a 50 km × 50 km spatial grid). Of these taxa, 15 are listed as national Class I protected species and 22 are categorized as Critically Endangered (CR), Endangered (EN), or Vulnerable (VU) according to the IUCN Red List, with most showing declining global population trends. Two Guangxi endemics and 11 karst-obligate species indicate high conservation irreplaceability. Species richness was concentrated in the central-northern Guilin–Liuzhou karst corridor and southwestern border regions, with a maximum of 13 taxa per 50-km grid cell. Occurrences were strongly biased toward low elevations, with 50.2% of records below 200 m. Principal component analysis identified temperature, particularly winter minimum temperature and seasonality, as the dominant environmental gradient (46.88% of explained variance), followed by precipitation-related factors (26.58%). These patterns, together with severe habitat fragmentation and anthropogenic pressures in lowland karst landscapes, underscore the urgent need for spatially targeted, climate-informed conservation actions in this globally important biodiversity region.
To elucidate the fluorescence characteristics of sediment dissolved organic matter (DOM), the structural and functional features of bacterial communities, and their coupling relationships under different vegetation coverage levels, sediment samples from distinct water depth zones of Baiyu Lake in Harbin, China, were analyzed using three–dimensional fluorescence spectroscopy and high–throughput sequencing. The results showed that sediment DOM had mixed allochthonous and autochthonous sources. Zones with helophytes and emergent plants exhibited a higher degree of DOM humification, higher humic–like fluorescence intensity, and elevated bacterial diversity, relative abundance of taxa, and OTU numbers associated with C, N, and S cycling. The Mantel test revealed significant correlations between allochthonous humic–like substances and bacterial community diversity, composition, and functions, whereas protein–like substances showed no such correlations. The variance partitioning analysis indicated that humic–like and protein–like substances explained 56.90% and 6.95% of the variance in the bacterial community, respectively. Collectively, vegetation variations driven by water depth modulate the complex interactions between sediment DOM and bacterial communities in lake wetlands.
Waste disposal sites significantly contribute to the degradation of primary environmental elements. In the Republic of Serbia, these waste disposal sites have been generated due to improper management of materials that are recyclable to varying degrees. Municipal waste disposal has led to issues such as contamination of surface and groundwater flows and a decline in the quality of agricultural crops. Current environmental management systems lack high levels of efficiency; preventive protection measures are not fully implemented, and corrective actions are frequently hindered by a lack of financial resources. Problem resolution is often limited to the application of “carpet-like” grass covers over degraded landscapes. The aim of this paper is to propose a model for overcoming these ecological issues. The proposal is based on a phased implementation, transitioning from simpler to more complex methods. Challenges associated with the direct application of modern reclamation methods include a shortage of professional personnel, financial constraints, and a lack of institutional readiness among the management of mining and energy complexes. The proposed environmental management system model for municipal solid waste landfills is based on Balanced Scorecard (BSC) and Critical Path Method (CPM) guidelines. By offering clear, efficient, innovative, and progressive strategic perspectives, this model establishes a robust foundation for multi-criteria decision-making and a multidisciplinary approach.
Fluoride enrichment in mine water is an emerging environmental concern in carbonate-hosted mining regions, yet its controlling mechanisms remain insufficiently constrained. This study investigates fluoride enrichment in 106 mine water samples from the Huaibei Coalfield, eastern China, using integrated hydrochemical analysis, mineral saturation indices, and positive matrix factorization (PMF). High-fluoride mine water is characterized by the coexistence of elevated Ca2+ and F‒, deviating from the conventional Ca-F antagonistic model typical of low-Ca groundwater. Saturation index results show that most samples remain undersaturated with respect to fluorite, and fluorite saturation is reached only after substantial fluoride accumulation, indicating that fluorite precipitation does not effectively limit fluoride levels. Weakly alkaline, bicarbonate-buffered conditions combined with prolonged waterrock interaction and evaporative concentration create favorable environments for fluoride persistence. PMF results reveal that fluorine-bearing mineral dissolution is the dominant contributor to fluoride enrichment (31.80%), followed by reverse cation exchange (28.75%), evaporative concentration (20.24%), and competitive adsorption (19.22%). These findings demonstrate that fluoride accumulation in Ca-rich mine water is driven by multiple coupled hydrochemical processes rather than a single mechanism, and they provide a quantitative framework for assessing fluoride contamination in similar mining environments.
Secondary organic aerosol (SOA) contributes greatly to atmospheric environmental pollution, and SOA tracers provide direct insights into the chemical composition, source identification, and formation pathways of SOA. Observations of SOA tracers were performed in Tai’an, a relatively clean city located in the North China Plain. Seventeen SOA tracers in PM2.5, which originated from isoprene (SOAI), monoterpene (SOAM), β-caryophyllene (SOAC), and aromatic hydrocarbon (SOAA), were measured and investigated. Characteristics of SOA tracers in different seasons and during different pollution days were revealed. The concentrations of these four kinds of tracers in summer were 28.5±7.49 ng m-3, 41.4±11.2 ng m-3, 1.94±0.72 ng m-3, and 1.26±0.51 ng m-3, respectively, indicating strong oxidation processes under high biogenic emissions. In winter, SOAI and SOAM decreased significantly by more than 65%, but the SOAA concentration increased by a factor of 2.65. These opposing trends collectively resulted in the same secondary organic carbon concentration (0.60 μg m-3) in summer and winter. Compared with non-pollution days, SOA was found to be fresher during O3 pollution days in summer and haze days in winter, but the underlying mechanisms were different. Through the combined analysis of malic acid, levoglucosan, and SO42‒, the importance of biomass burning and secondary inorganic formation to SOA was revealed. This study provides insights into SOA characteristics in a mountain city under relatively clean conditions.
This study evaluated the potential of Total Reflection X-ray Fluorescence (TXRF) as a geochemical traceability method for wood from Manilkara huberi (Ducke) A. Chev., a species of high commercial and ecological value widely exploited in the Legal Amazon. Wood samples were collected in eight locations in the states of Amazonas, Par & aacute;, Rond & ocirc;nia, and Roraima, representing different edaphic, geological, and climatic conditions in the context of Amazonian edaphic and geological variability. The multielemental analysis revealed significant variations in trace element and macronutrient concentrations (Fe, Mn, K, Ca, Sr, Rb), reflecting the specific geochemical signatures of each region. Multivariate analyses (PCA and NMDS) showed distinct groupings among the populations, confirming the discriminatory capacity of TXRF in the differentiation of geographical origins. Significant correlations between elements such as K & times; Rb and Cr & times; Fe demonstrated consistent patterns of coaccumulation and antagonism associated with local geochemistry. The results prove the efficiency of TXRF as a non-destructive, sensitive, and low-cost technique for origin authentication and forensic investigation of Amazonian wood, strengthening sustainable management policies and combating illegal exploitation. The proposed methodology is a scientific advance in forest traceability and biodiversity conservation, contributing to the transparency and legality of timber production chains in the Amazon.
Mariculture of white leg shrimp, Litopenaeus vannamei, provides a crucial protein source for humans. Aquaculture of this species also generates significant nitrogen (N) pollution, which can trigger harmful algal blooms in coastal environments. Although mariculture typically has low profitability, it is essential to establish ecologically and economically sound ways to minimize the release of N into the environment. Oyster polyculture within L. vannamei ponds presents a promising approach for reducing the release of N because oysters have a strong capacity to filter N from the environment while producing a marketable commodity. This study investigated spatiotemporal variations in dissolved N forms (NH4+, NO2-, NO3-, and total N) in shrimp pond water with and without oyster co-cultivation. The results demonstrated that the oyster-integrated pond exhibited significantly lower N pollutant concentrations when compared with the control pond. Specifically, NH4+, NO2-, NO3-, and total nitrogen content decreased by 39.8%, 52.6%, 27.3%, and 51.4%, respectively. Notably, these reductions lowered N concentrations below local regulatory thresholds for the discharge of mariculture wastewater. These findings highlight the potential for the use of oyster polyculture as an effective and dual-purpose method that can be used to mitigate N pollution while maintaining shrimp production yields for L. vannamei mariculture.
Argentina anserina（A. anserina, a perennial herb endemic to the Qinghai-Tibet Plateau, develops unique root structures commonly referred to as “ginseng fruit.” These roots possess significant nutritional and medicinal properties. This study utilizes ethnobotanical methodologies to document the traditional knowledge associated with A. anserina among Tibetan communities in the Qinghai-Tibet Plateau region, supplemented by food science analyses to ascertain its fundamental nutritional composition. The principal findings indicate that A. anserina plays a multifaceted role in traditional Tibetan livelihoods. Quantitative analyses reveal that its edible (RFC0.92) and medicinal (RFC0.78) applications significantly exceed other uses in terms of relative citation frequency, establishing these as the predominant utilization patterns. Traditional harvesting methods yield A. anserina specimens characterized by high dietary fiber content, low sodium levels, abundant amino acids, and a diverse array of mineral elements. These findings highlight the substantial potential for the development and utilization of A. anserina. Strategic artificial cultivation could enhance production, potentially increasing residents’ income and promoting rural revitalization in remote areas. This investigation provides a theoretical foundation for the subsequent processing and utilization of edible A. anserina.
The efficiency of different inorganic phosphorus (P) sources in an alkaline calcareous soil is significantly reduced due to elevated pH levels, which lead to phosphorus immobilization and the formation of insoluble phosphorus compounds with calcium (Ca). In this study, a greenhouse experiment was conducted to determine the efficiency of various P fertilizers using different rates of biochar. Using a completely randomized design (CRD), three levels of biochar were used: 0%, 1%, and 2% (w/w of 17 kg of soil), followed by three types of inorganic P fertilizers, i.e., single superphosphate (SSP), double superphosphate (DAP), and rock phosphate (RP). The application of biochar significantly increased phosphorus use efficiency (PUE). The PUE of SSP and DAP fertilizers was greatly increased by the 2% biochar application in the soil, i.e., 22.43% and 21.41%, respectively, as compared to the control (12.06%). Moreover, soil pH declined from 7.84 to 7.58 by the 2% biochar application in the soil, and a reasonable increase in soil chemical characteristics was reported, providing an optimum range for nutrient availability. Overall, soil available P, plant P contents, plant P uptake, and PUE were significantly affected by both biochar and inorganic P sources, which indicates that these findings can be valuable for understanding and optimizing agricultural practices, soil management, and plant growth in relevant ecosystems.
The aim of this study is to objectively evaluate the adsorption performance of biochar. The performances of various biochars in adsorbing pollutants were thoroughly evaluated and compared using a combination of Analytical Hierarchy Process (AHP) and Grey Relational Analysis (GRA). The importance rankings of adsorption amount, adsorption time, and specific surface area in adsorption performance were determined through AHP, and the weights of each index were calculated to ensure consistency. Utilizing GRA, the degree of correlation between specific surface area, adsorption time, and adsorption performance was assessed, with adsorption amount as the reference value, which further validated the AHP results. The results show that adsorption capacity holds the highest weight at 64.83%, followed by adsorption time at 22.97%, and specific surface area at 12.20%, based on the AHP analysis. The GRA further confirms a stronger correlation between adsorption time and adsorption capacity, highlighting the greater influence of adsorption time on adsorption performance compared to specific surface area. These findings offer crucial guidance for applying biochar in environmental management, enhancing pollutant removal processes, optimizing material choices, and supporting environmental protection and sustainable development initiatives.
The discharge of antibiotic residues into aquatic environments promotes antimicrobial resistance (AMR). Conventional wastewater treatment is ineffective at removing these persistent micropollutants, necessitating the use of advanced strategies. This review critically assesses the efficacy of advanced oxidation processes (AOPs), adsorption, membrane separation, and advanced biological treatments for antibiotic removal from pharmaceutical wastewater. While techniques like photocatalysis and ozonation achieve high degradation rates (>90%) in controlled settings, significant challenges, including energy consumption, catalyst management, toxic byproduct formation, and economic feasibility, hinder their scalability. Findings indicate that successful demonstrations remain confined mainly to synthetic wastewater in laboratory studies. This review identifies a gap between lab research and real-world use. We conclude that overcoming this barrier requires a dedicated focus on developing hybrid treatment systems. This review therefore recommends prioritizing the development of scalable, cost-effective solutions validated with complex, real-world wastewater to mitigate the environmental and public health risks posed by antibiotic pollution.
Microplastics (MPs) are emerging contaminants with uncertain effects on plants, particularly ornamentals. We tested how polyethylene (PE), polylactic acid (PLA), and a constant-total-dose 1:1 (w/w) mixture of PE and PLA (MIX; 25 mu m) at 0.1% (w/v), 0.5% (w/v), and 1.0% (w/v) influence seed germination and early growth of white clover (Trifolium repens) in Petri-dish assays. Although these exposure levels exceed typical background levels in bulk soils, they were used to represent worst-case/high-exposure scenarios to elucidate potential mechanisms and effect thresholds in a 7-day assay. Endpoints included germination potential and final germination rate, root traits (radicle elongation inhibition rate and root-to-shoot ratio), seedling biomass (fresh/dry mass), and water content. Responses generally followed a dose-dependent hormetic pattern, with low-dose PE increasing final germination rate, while higher exposures impaired root development and altered biomass allocation. Notably, the high-dose MIX treatment reduced the root-to-shoot ratio by similar to 37% relative to the control, suggesting disrupted allocation and/or disproportionate root impairment under intense MP stress. Water relations were polymer-specific: PE reduced seedling water content across all tested levels, consistent with physical blockage and/or impaired root water transport, whereas PLA and MIX caused significant declines mainly at higher concentrations. Overall, polymer identity and concentration jointly regulated early establishment, supporting the "low-dose stimulation, high-dose inhibition" framework and underscoring the need to consider both biodegradable and conventional MPs in ecological risk assessment.
Gum arabic (Acacia senegal) is a multipurpose tree widely distributed throughout the Sudano- Sahelian region of sub-Saharan Africa, extending from Sudan to Senegal. It is best known for being the main source of high-quality commercial gum arabic, a bark exudate used in a variety of food, pharmaceutical, and industrial products. Gum arabic trees are conventionally propagated through seeds. However, in addition to the difficulty in obtaining selected seeds every year, poor germination, and the death of young seedlings in the natural habitat, this method results in high genetic diversity within the species’ populations. In vitro micropropagation may be the best substitute to avoid the drawbacks of traditional propagation. Micropropagation promotes large-scale commercial plantations and sustainable agriculture to satisfy the growing global demand for gum arabic. Additionally, it can be used for conservation, genetic enhancement, and production of disease-free planting materials. However, despite its potential, gum arabic tree micropropagation methods face several difficulties, including a poor multiplication rate, low rooting, and a high mortality rate during acclimatization. In this review, we first provide an overview of gum arabic trees and their conventional means of propagation, and then describe all published research and the most up-to-date information on the progress made in the field of gum arabic tree micropropagation from 1973 to 2025. The challenges and future perspectives of this study are also outlined.
Achieving low-carbon innovation under the “dual-carbon” goal has become a pressing issue. Based on the innovation ecosystem theory, this study uses a sample of 30 provinces in the Chinese mainland and employs fuzzy set qualitative comparative analysis (fsQCA) to examine the complex causal mechanism of seven factors affecting low-carbon innovation, namely, market innovation subjects, R&D innovation subjects, human resources, financial resources, information resources, market orientation, and government support. The results show that no single factor qualifies as a necessary condition for high provincial low-carbon innovation. Five configurations generate high provincial lowcarbon innovation, and three configurations generate non-high provincial low-carbon innovation. There is an asymmetric causality relationship between the configurations that generate high and non-high provincial low-carbon innovation. This study provides a new perspective for the research on low-carbon innovation and insights for achieving provincial low-carbon innovation.
