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[Display omitted] • Illustrating the impacts of LULC changes on the landscape spatiotemporal patterns. • Evaluated the ecological security of the Ebinur Lake Wetland Reserve. • Ebinur Lake levels have been shrinking, and salinization is increasing annually. • Proposed ecological protection policies for the government. There is an increasing contradiction between humanity's growing demand for natural resources and relatively limited supplements. Thus, ecological security has received widespread attention, making it a research hotspot in the global environment and an important topic in construction of ecological civilization. Ebinur Lake Wetland is a typical arid wetland area considered as a fragile and sensitive ecosystem. Quantitative monitoring of the ecological security and landscape patterns of the Ebinur Lake wetland ecosystem is of great significance for environmental protection. To clarify the relationship between ecological landscape indices and land use/cover, this study used Landsat TM/OLI data from 1990, 1998, 2011 and 2021, aimed to analyze the correlated spatio-temporal changes of Ebinur Lake Wetland Reserve, China over past 32 years, in addition to quantitatively evaluating changes in ecological security. The results showed that (1) During 1990–1998, forest and paddy areas increased, while the transformation between paddy fields and wetlands was frequent, and from 1998 to 2011, land use/land cover (LULC) changes gradually stabilized, vegetation recovery was halted, and the water area obviously decreased. Since 2012, Ebinur Lake area decreased by −3.88 % per year, while 44.8 km2 of the subsoils became extremely severe salinized. (2) The variability of ecological landscape in spatial structure and time dynamics is enhanced, landscape scalability declined, resulting in the intensification of fragmentation. CONTAG (Contagion index) decreased annually with the decline in Gobi area; whereas landscape diversity of wetlands increased with growing light and heavy saline-alkali areas. (3) Overall ecological security gradually increased from 0.56 to 0.65, and the unsafe areas first decreased, before increasing slightly. The total saline-alkaline land area continued to increase, indicating that desertification cannot be curbed. Ecological security had the highest sensitivity to landscape separation, and the value range and its safety levels of ecological security (ES) were accurately delimited based on uncertainty calculation and frequency statistics. The results can provide reasonable and practical suggestions for the government and local communities on how to strengthen the ecological environment construction of Ebinur Lake Wetland Reserve. The government should several water-saving measures, in addition to an inter-basin water transfer project can be implemented to help diminish the consequences of insufficient water resources, and planting salt-absorbing vegetation to slow the salinization process. [ABSTRACT FROM AUTHOR]

Ustiloxins, a group of bioactive metabolites produced by the pathogen of rice false smut (RFS), have emerged as ubiquitous contaminants in RFS-occurred paddy fields and could accumulate in rice. Nevertheless, the prevalence of ustiloxins in rice and exposure risks of humans are limited. In this study, concentrations of ustiloxin A (UA) and ustiloxins B (UB), which are two predominant ustiloxins, were measured in 240 rice samples from China and 72 rice samples from 12 other counties. The detection rates (DRs) of UA and UB were 82.1% and 49.3%, respectively, and their concentrations in rice ranged from below detection limit (LOD: 0.22 μg/kg) to 85.96 μg/kg dw. Furthermore, for the first time, we reported the occurrence of UA (DR = 22.8%) in urine collected from residues of Enshi city, China. Urinary UA were significantly correlated with the activities of alanine aminotransferase in male, and this male-biased hepatotoxicity was further confirmed in mice exposure experiment. This study for the first time reported the widespread geographical distribution of ustiloxins in rice, as well as emphasized the occurrence of internal exposure and potential health risk in humans. [Display omitted] • Ustiloxin contamination in polished rice was ubiquitous globally. • Occurrence of UA in human urine was observed with detection ratio of 22.8%. • Urinary UA level was significantly correlated with ALT activity in male. • Male-biased hepatotoxicity of UA was confirmed in mice. [ABSTRACT FROM AUTHOR]

Marine sediments serve as a sink for contaminants of anthropogenic origin. Here, 25 major and trace elements were determined in surface and core sediments from an urban lagoon (Yundang Lagoon), China. The median concentrations of Pb, Cd, Cu, and Zn in both surface and core sediments exceeded global and crustal averages. Principal component analysis for the elements and ecological impact of the heavy metals indicated spatial heterogeneity in core sediments from different lagoon areas; however, no such pattern was observed in surface sediments. Geodetector analysis indicated spatial locations of lakes, pH, N%, C%, and S% as the major factors influencing the heterogeneity of potential ecological risk index, a cumulative measure of the ecological impact of heavy metal. The interaction detector indicated nonlinear and bivariate enhancement between different physicochemical parameters. Besides, a depth profile of the elements in different samples was also elucidated. [Display omitted] • Anthropogenic activities cause the metal pollution in Yundang Lagoon. • Major and trace elements were higher at surface sediments compare to the core sediments. • PCA indicated spatial heterogeneity in the distribution of metalloids. • Risk assessment indices indicated moderate to extreme contamination by heavy metals. • Geodetector analysis indicated association of potential environmental risks of metals with sediment variables. [ABSTRACT FROM AUTHOR]

Root rot is a major disease of strawberry (Fragaria × ananassa cv. Duchesne) worldwide affecting production and leading to huge economic losses. In 2018 and 2019, strawberry plants displaying root rot symptoms accompanied by plant wilting were observed on commercial farms in Beijing, China. A fungus with the general morphological characters of Neopestalotiopsis was consistently isolated from necrotic lesions in symptomatic roots. Eight representative isolates were selected for further studies. Based on morphological characters and phylogenetic analyses of the combined internal transcribed spacer (ITS) region, partial sequences of the β-tubulin gene (tub2) and the transcription elongation factor 1-α (tef1), all isolates were identified as Neopestalotiopsis rosae. Pathogenicity test showed that N. rosae can produce wilt and root rot symptoms on strawberry plants. Therefore, N. rosae was recognized as the causal agent of root rot of strawberry. This is the first report that discusses the role of N. rosae in causing root rot disease on strawberries in China. 1. Root rot symptoms accompany with plant wilt were observed on strawberry in Beijing, China. 2. Neopestalotiopsis rosae was identified based on morphological characteristics and multilocus phylogenetic analyses. 3. The isolates fulfilled Koch's postulate. 4. This is the first report of N. rosae causing root rot of strawberry in China. [ABSTRACT FROM AUTHOR]

Recently, we found that Ustiloxin A (UA, a mycotoxin) was widely detected in paddy environment and rice samples from several countries, and was also detected in human urine samples from China. However, the current knowledge about the health risks of UA are limited. In this research, the cytotoxicity of UA in mice renal tubular epithelial cells (mRTECs) was evaluated, and the results indicated that UA arrested cell cycle in G2/M phase via altering cellular morphology and microtubule, and inhibited the proliferation and division of mRTECs. Furthermore, UA could inhibit mitochondrial respiration via binding to the CoQ-binding site in dihydro-orotate dehydrogenase (DHODH) protein, and resulted in mitochondrial damage. These adverse effects of UA on mitochondria might be responsible for the cytotoxicity observed in vitro. In vivo , UA at concentrations that were comparable to the realistic concentrations of human exposure induced renal insufficiency in mice, and this might be associated with the renal mitochondrial damage in mice. However, exposure to UA at those realistic concentrations did not promote the progression from renal insufficiency to renal fibrosis and chronic kidney disease was not observed in mice. [Display omitted] • UA inhibits proliferation of renal tubular epithelial cells. • UA induces renal injury in mice. • UA disrupts structure and respiratory function of mitochondria. • UA binds to the CoQ-binding site in dihydro-orotate dehydrogenase protein. [ABSTRACT FROM AUTHOR]

This paper studies examines how a firm's position in the global value chain affects its pollutant emissions. This paper integrates China's firm-level trade data into China's multi-regional input-output tables to provide an index to measure a firm's position in global value chains. Based on a firm-level pollution dataset (2000–2014) in China, this paper conducts an empirical analysis and find that the most-downstream firms on the global value chain have lower pollutant emission intensity. Our results also suggest that the production factor structure effect, the knowledge absorption effect and the abatement investment effect together contribute to the emission intensity gap between the most-upstream firms and the most-downstream firms. These novel results are significant in guiding firms towards reducing their emissions and promoting a green global value chain, with the ultimate goal of achieving multinational environmental protection. [Display omitted] • The most-downstream firms have lower pollutant emission intensity. • A supply chain disruption shock is used as an instrumental variable. • Factor structure, knowledge absorption and abatement investment are channels. • Effects on firms with diverse ownership and trade patterns are heterogeneous. [ABSTRACT FROM AUTHOR]

Freezing rain usually occurs when snow falls into an above-freezing layer aloft where it melts before reaching the sub-freezing surface as supercooled water. Although the occurrence of freezing rain is uncommon, it can produce extremely costly impacts. To date, field chemical observations of supercooled drops that form freezing rain are lacking. In this study, we collected 101 precipitation (freezing rain/rain/snow) samples on Mt. Heng in southern China for 7 years in the winters between 2015 and 2021. The winter precipitation collected at Mt. Heng was mostly acidic with pH values lower than 5. Acidity, contributed from NO 3 − and SO 4 2−, was neutralized by NH 4 + and Ca2+, indicating the additional contribution from organic acids. The major ions were NH 4 +, Ca2+, SO 4 2− and NO 3 −, with concentrations of 135.7, 86.3, 72.5 and 61.8 μeq L−1, respectively. In general, the total ionic concentrations of freezing rain were, in comparison with mountain-based observations elsewhere, lower than those in cloud water but higher than those in rain. The higher concentrations of major ions in freezing rain would depress the freezing point of supercooled water drops and act to reduce the likelihood of freezing with effects increasing with concentration. This process would be countered by the presence of ice nuclei that is acting to freeze supercooled drops. These opposing processes complicate the understanding of the onset of freezing and consequently the occurrence of freezing rain. This study highlighted that additional model simulations and laboratory experiments are needed to validate the relationship between air pollution and freezing rain. [Display omitted] • First chemical study on freezing rain for 7 years at Mt. Heng in southern China. • Ionic contents of freezing rain were lower than cloud water but higher than rain. • The minimum temperature of freezing rain decreased as ionic concentrations increase. [ABSTRACT FROM AUTHOR]