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Besides, sulfate input increased MeHg levels (89-240%) in soils with low ambient sulfate levels (380 mg kg-1). These could be explained by the diverse responses of Hg mobility and microbial Hg methylators to sulfate input at different ambient sulfate levels. Our study opens the "black box" of Hg methylation under sulfur input, which would help reduce uncertainties in predicting MeHg risk in soils.Density (ρ) is one of the most important physical properties of aerosol particles. Owing to the complex nature of aerosols and the challenges of measuring them, effective density (ρe) is generally used as an alternative measure. Various methods have been developed to quantify the ρe of aerosols, which provide powerful technical support and understanding of their physical properties. Here, we present a comprehensive review of the characterisation techniques of ρe currently used in the literature. Overall, six categories of measurement are identified, and the typical configuration, measurement principles, errors and field applications of each are demonstrated. Their respective advantages and disadvantages are also discussed to improve their application. Finally, we outline future directions for further technical improvement in, and instrumental development for, ρe measurement.This study presents a comprehensive review of the Land subsidence (LS) cases, as a worldwide environmental, geological, and global geohazard concern. Here, 290 case studies around the world mostly conducted in large metropolitan cities (e.g. Bangkok, Beijing, California, Houston, Mexico City, Shanghai, Jakarta, and Tokyo) in 41 countries were collected. The spatial distribution of LS characteristics (e.g. intensity, magnitude, and affected area), impacts, and influential factors are scrutinized. Worldwide attempts to remedy the crisis of LS were also investigated in this review. It is shown that the coastal plains and river deltaic regions are of high-frequent subsided areas around the world (~47% of 290 study areas). The spaceborne monitoring of LS is the more prevalent technique (~ 38% of total cases) compared to the ground-investigation (e.g. geological surveying, leveling, GPS, and modeling). Human-induced LS cases are 76.92% of all the LS cases around the world and groundwater extraction contributes 59.75% of these cases. Strong direct correlations with the exponential trend are observed between the average LS rate (LSavg) with groundwater withdrawal (R2 = 0.950) and groundwater level decline (R2 = 0.888). To understand the influential factors on LS occurrences, the relationship of LS rate with climate factors, hydrogeological characteristics of the aquifer, human-induced factors are investigated. Finally, we provide future research guidelines and implications that need to be expanded in order to better monitor and reduce the impact of the LS phenomenon. The outcomes of this study can be used to derive a framework helpful for interpreting the observed LS phenomena and for forecasting future situations to mitigate or control this geohazard.Habitat fragmentaion into small patches is regarded as a vital cause of biodiversity loss. Fragmentationof habitat-forming species is especially harmful, as patchiness of such species often controls ecosystem stability and resilience by density and patch size-dependent self-reinforcing feedbacks. PDD00017273 supplier Although fragmentation are expected to weaken or even break such feedbacks, it remains unclear how the resulting patchiness of habitat-forming species affect ecosystem resilience to environmental stresses. Here, using Spartian alterniflora, the habitat-forming species in saltmarshes as a model, we investigate how patch size, plant density, and shell aggregation interactively control the persistence of a degrading salt marsh that suffered from erosion induced by hydrodynamics. Our results demonstrate that large patches can trap more shells along the patch edge than the smaller ones, therefore significantly facilitating plant re-growth within the patch. Shell removal experiments further reveal that large patches trapping more shells along patch edges reinforce their own persistence by decreasing erosion and thus facilitating plant recovery. By contrast, small patches with lesser plants cannot persist as they trap less shells along patch edges but are able to accumulate more shells at interior locations where they hinder plant re-growth, indicating a critical threshold of patch size ~20 m2 below which ecosystem collapses. The current study highlights the importance to identify critical threshold of stress-resistant patch sizes in transition-prone ecosystems as early-warning to alert undesired ecosystem collapse and restoration practice.The abuse of psychoactive substances has been increasing dramatically over the last few years, which is becoming a concern for human health and social stability. How to accurately estimate psychoactive substances' total consumption in certain areas is the key to manage such substances. In order to control psychoactive substances, 8 psychoactive substances' consumption within 12 wastewater treatment plants (WWTPs) service areas in a certain city of Guangxi, China was investigated in 2019. Firstly, a solid-phase extraction-liquid chromatography-tandem mass spectrometry method was used to determine the influent concentrations. Morphine (MOR), 3, 4-methylenedioxymethamphetamine (MDMA), methamphetamine (METH), ketamine (KET), and norketamine (NK) were detected, with the concentrations ranging from less than method detection limit (NK, MDMA) to 170.91 (METH) ng/L. Then, the back-estimation of consumption was conducted according to the objective and near real-time wastewater-based epidemiology (WBE). The results demonstrate that KET, MOR, and METH are the most abused psychoactive substances, with the mean consumption of 682.42, 167.81, and 44.56 mg/day/1000 inh, respectively. The psychoactive substance residues of WWTPs influent were analyzed to estimate such substances' consumption in specific areas, so as to provide support for risk prevention and control.Microplastics (MPs) pollution becomes an emergent threat to the ecosystem, and its joint effect with organic contaminants will cause more severe consequences. Recently, MPs has been observed in human feces, suggesting that we are exposed to an uncertain danger. In this study, the joint effect of polyethylene microplastics particles (PEMPs) and Tetrabromobisphenol A (TBBPA) on human gut was explored through the simulation experiment in vitro with human cell Caco-2 and gut microbiota. The toxicity of TBBPA and PEMPs on Caco-2 human cells was considered by physiological and biochemical indexes such as cell proliferation, cell cycle, reactive oxygen species, lactate dehydrogenase release, and mitochondrial membrane potential. Besides, microbial community diversity, community structure, and function changes of gut microbiota were investigated using Illumina 16S rRNA gene MiSeq sequencing to reveal the influence of TBBPA and PEMPs on human gut microbiota. The results indicated that both PEMPs and TBBPA would deteriorate the status of Caco-2 cells, and TBBPA played a major role in it; meanwhile, PEMPs affected Caco-2 cells at high concentrations.