Watershed

In this study, the optimization strategy and underlying mechanisms of chemical deep phosphorus removal using polyferric sulfate (PFS) were systematically investigated through a combination of engineering validation and mechanistic analysis, revealing the FePO4 precipitation-dominated phosphorus removal mechanism and the influence of coexisting impurities and clarifying the key liganding role of Fe3+ by FTIR/XPS. The engineering applicability of secondary PFS dosing and PFS–polyacrylamide (PAM) codosing was validated in a full-scale wastewater treatment plant with a treatment capacity of 4 × 104 t·d–1, where a substantial enhancement in orthophosphate (Ortho-P) removal efficiency was achieved (increased by 30.6% and 28.1%, respectively). In addition, the threshold effects of PFS on the microbial activity in the AAO system were clarified under practical operating conditions. Collectively, this study offers both theoretical insights and engineering-level evidence to support the fine regulation of chemical phosphorus removal in wastewater treatment plants (WWTPs), and it exhibits substantial practical value for enhancing phosphorus removal efficiency and operational stability.

Continental chemical weathering plays a crucial role in the regional and global carbon budgets. However, relevant research on tropical volcanic islands is still limited, particularly the influences of human activities on surficial chemical weathering, which remain scarce. This study analyzed the water geochemistry and dissolved inorganic carbon isotope (δ13CDIC) of the Changhua River draining Hainan Island, aiming to quantitatively elucidate the seasonal CO2 budgets at the catchment scale. We found that the major ions in the river were from atmospheric precipitation (6.79%), anthropogenic input (11.68%), carbonate weathering (41.96%), and silicate weathering (39.56%). The silicate weathering rate and the carbonate weathering rate were calculated as 16.91 t km–2 yr–1 and 30.68 t km–2 yr–1, respectively, resulting in CO2 consumption of 307.82 × 103 mol km–2 yr–1 and 400.95 × 103 mol km–2 yr–1. Considering sulfuric acid- and nitric acid-driven weathering reactions, the catchment became a net source of CO2 on a geological time scale. Furthermore, the drivers of chemical weathering and associated CO2 budget were deciphered. The significant positive correlations among chemical weathering fluxes, acids, and land uses quantitatively emphasized that the chemical weathering of CO2 budgets was largely disturbed by anthropogenic activities. This study showed that integrating river water geochemistry and geographical parameters could achieve a deep understanding of catchment weathering CO2 budgets and potential driving mechanisms.

AI-generated art has its roots in the 1960s, driven by pioneering artists experimenting with algorithmic and rule-based systems. In contrast, over the past decade, new AI art generators, fuelled by increased computing power, are often associated with extractive data practices spearheaded and monopolised by big tech companies. Both historical and contemporary approaches involve learning patterns from existing data to generate new content; however, early work was primarily artist-led and exploratory in nature, whereas today’s generative AI is largely shaped by big tech for-profit interests. This shift has provoked both excitement and scepticism in the creative industries, while raising concerns around authorship, privacy, forgery, discrimination, and the ethical implications of unjust machine learning techniques which erode creators’ rights, under the guise of technological progress and the democratisation of artistic creativity. This paper examines how values, beliefs, and emotions shape UK arts practitioners’ engagement with narrow AI and artistic automation. Through thematic analysis of interviews and focus groups with artists, curators, and organisers, three major narrative themes emerge: (1) a critical perspective on tech-driven artistic automation, (2) calls for improved human-machine collaboration, and (3) tensions arising from personal values, beliefs, and emotional responses. These findings highlight that arts-led AI practitioners offer a necessary counterbalance to the widespread adoption of tech-centric automation in art, advocating for more ethical, collaborative, and value-driven approaches as automation becomes increasingly pervasive in the creative sector.

Identification of disinfection byproducts (DBPs) precursors remains a longstanding challenge due to the complexity of contaminated source water. Tire wear particles (TWPs) can be an overlooked source of DBPs precursors. To figure out the specific amine additives in tire rubber serving as potential nitrosamine precursors during chlorination, six frequently measured tire-derived amine additives, including N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine (6PPD), N-isopropyl-N′-phenyl-p-phenylenediamine (IPPD), N-cyclohexyl-N′-phenyl-p-phenylenediamine (CPPD), N,N′-dicyclohexylurea (DCU), diphenylamine (DPhA), and N,N′-dicyclohexylamine (DCHA), were selected to simulate their degradation processes, and their DBPs formation potentials were evaluated under various water matrices. IPPD was found to have a high molar yield of N-nitrosodimethylamine (NDMA, up to 8%), while 6PPD exhibited a lower molar yield (∼0.1%) with the molar ratio of chlorine-to-ammonium nitrogen (Cl2:N = 2) and disinfectant-to-precursor (D/P = 10). Suspect and target screening approaches were further applied to identify the transformation products of IPPD, and the formation pathway of NDMA via IPPD was proposed. Furthermore, we assessed NDMA formation from IPPD in simulated TWP leachates through chlorination experiments in the presence of ammonia, which revealed that IPPD contributed up to 24% of the total NDMA formed. This study offers new insights into the previously overlooked source of nitrosamines from tire-derived amine additives.

Compost-derived humic acids (HAs) and fulvic acids (FAs) play an essential role in enhancing soil microbial diversity and activity by facilitating metabolic processes through electron transfer. Herein, the effect of bioleaching dewatered sludge (BDS) in comparison with filter press dewatered sludge (FDS) on the electron transfer capacity (ETC) of humic substances during composting was investigated as a novel attempt. A variety of characterization methods including UV-Vis, FTIR, 3D-EEM, and electrochemical measurements, were used to explore the change in humic substances during composting. The results indicated that bioleaching treatment significantly influenced the organic matter composition and hindered the accumulation of redox-active functional groups during composting. Notably, the ETC of HA increased by 24.07% in the FDS group but declined by 40.62% in the BDS group. This divergence stemmed from the organic matter loss during bioleaching, leading to reduced quinone-like and tryptophan-like substances associated with electron transfer in HA during composting. Furthermore, BDS showed lower pH, water content, and organic matter, but higher concentrations of ammonium nitrogen (NH4+-N) and ammonia nitrogen NH3−-N, all of which potentially influenced humification efficiency. These findings not only clarify the electron-transfer dynamics of humic fractions but also highlight the importance of optimizing sludge pretreatment for improved composting performance and resource recovery.

Photovoltaic (PV) technology is the core pathway foraddressingglobal climate change and advancing energy system decarbonization,yet the rapid expansion of PV manufacturing capacity has triggereda surge in life-cycle greenhouse gas emissions, sparking mountingconcerns. We integrated multisource heterogeneous data from China’sPV industry (2005–2024) to develop a life-cycle accountingframework, which quantifies industrial carbon emissions and theirevolutionary patterns across production stages and multiscale spatiotemporaldimensions. We also deconstructed the emission impacts of scale, technology,and structural factors, and predicted future trends. Over two decades,China’s PV industry-wide carbon emissions soared from 0.24to 205 million tonnes, while product-level emission intensity plummetedfrom 1,300 to 380 kg CO2eq/kWp. The contribution of technologicalprogress to emission reduction rose from about 3% of the observedincrease in emissions in 2005–2007 to nearly 100% in 2020–2024.Spatially, raw material and monocrystalline cell production have shiftedinland for cost advantages, while module assembly remains concentratedin coastal hubs like the Yangtze River Delta. Capacity utilization,grid decarbonization, and technical learning will dictate future emissions.Against surging global PV demand, coordinated capacity planning, acceleratedtech progress, optimized spatial distribution, and established incentivepolicies are pivotal to steering China’s PV manufacturing ontoa sustainable low-carbon path.

This study presents a multidisciplinary reconstruction of a paleolake’s Holocene evolution in Iran’s Central Plateau, synthesizing sedimentological, geochronological, archeological, and historical evidence. Our findings confirm the existence of a large paleolake (~16–14 ka) in the northern plateau, with episodic desiccation and recharge. Lake levels declined by 250 m between 11.5 and 8.2 ka, stabilizing at ~850 m elevation. The 8.2 ka climatic cooling event triggered regional aridification, prompting human migration to warmer lowlands. We propose that the Masileh Basin, hydrologically active until the Sassanid era, represents the residual footprint of the mythologized Lake Saveh. By correlating Late Pleistocene–Holocene hydrological dynamics with settlement patterns, this work establishes a direct linkage between climatic forcing, tectonic controls, and anthropogenic responses. The integration of geological archives with archeological and historiographical data resolves long-standing ambiguities surrounding the lake’s existence while demonstrating how environmental transitions became encoded in cultural memory.

Glacial isostatic adjustment (GIA) profoundly influences postglacial tectonics, sea-level change, and geothermal systems; however, its role during the deglaciation of the Neoproterozoic Snowball Earth remains poorly constrained. Sheet-crack is one of the diagnostic structures in Marinoan (635 Ma) cap carbonates that overlie glacial tillites. Available geochemical evidence indicates that sheet-crack cements precipitated immediately following crack formation, potentially preserving GIA-driven fluid signatures. This study presents fluid inclusion microthermometric data from sheet-crack quartz and barite cements along shelf-to-slope transects on the Yangtze Block, South China. Fluid inclusion homogenization temperatures (Th) reveal the occurrence of a ubiquitous low-temperature hydrothermal event, with most Th values clustering at ∼145 °C–190 °C and ∼120 °C–180 °C in platform facies and slope facies, respectively. Fluid salinities in platform facies exhibit unimodal distributions and low to moderate (∼2–8 wt % NaCl eq.), while those in slope facies show broadly continuous distributions, with most values concentrated at intermediate-to-high salinities (∼6–15 wt % NaCl eq.) and a subordinate low-salinity tail. These patterns are consistent with varying contributions from recirculated, geothermally heated seawater and basinal brines. We propose a refined model in which GIA-related geothermal anomalies promoted a widespread low-temperature hydrothermal circulation event, responsible for sheet-crack cementation shortly after the Marinoan deglaciation, South China.