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We used the Integrated Biological Responses version 2 (IBRv2) method to evaluate the biological effects of heavy metals in the sediments in Laizhou Bay, China on the benthic goby Acanthogobius ommaturus. In December 2018, gobies and sediments were collected from 15 stations. We measured the activities of defense enzymes and the contents of malondialdehyde (MDA) and metallothionein (MT) in the goby liver as well as the levels of heavy metals in the sediments and goby muscle tissue. Most of the heavy metal concentrations in sediment at each station were below the Class I criteria set by Chinese Standards for Marine Sediment Quality, and the Håkanson ecological risk index suggested low risk for the heavy metals. We found that A. ommaturus could effectively accumulate mercury, cadmium, arsenic, and zinc and that the contents of MT and MDA and the activities of glutathione peroxidase and glutathione reductase were suitable biomarkers of heavy metal pollution in this species. The IBRv2 method integrated these four biomarkers and discriminated stations according to heavy metal pollution. Higher IBRv2 values suggested more adverse effects in gobies, corroborating more serious heavy metal contamination. The stations with high IBRv2 values and high contents of heavy metals were mainly distributed in the west and northeast parts of the bay. These results show that the IBRv2 approach is a feasible strategy for assessing heavy metal pollution through biological response and biological status and that it can be implemented for environmental monitoring in Laizhou Bay. [ABSTRACT FROM AUTHOR]

The river-blocking effects of debris flows have become common in numerous catchments in response to climate and environmental changes, and these effects have caused multiple, overlapping, and interconnected chain reactions that have led to huge losses in alpine regions. Considering this issue, this article developed a quantitative method for the regional river-blocking hazard assessment of debris flows by analyzing the in-depth relations among river-blocking hazard formation processes, factors and evolution mechanisms. Taking the debris flows in the Parlung Zangbo Basin in China as a case study, a multidimensional analysis was performed to analyze the characteristics of the hazard sequence and its relationship with climate change, including changes in temperature and precipitation. Accordingly, a new step toward a more comprehensive hazard assessment is proposed by establishing both a model and a system for regional river-blocking hazard assessment to analyze the debris flow evolution processes and environmental dynamics. Specifically, the sources of loose material were quantitatively estimated by establishing mathematical models based on the geometrical characteristics of diverse moraines, and the debris flow runoff was scientifically determined by focusing on the analysis of moraine sources, the brittleness index of the sediment mass and the geomorphological connectivity. Next, through coupling with the hydrodynamic conditions of debris flows and river flows, methods were established to determine the blocking degree of debris flow hazards at the regional scale. Validated by a field study and a remote-sensing interpretation of actual debris flows, a debris-flow-induced river-blocking hazard map was obtained, and the assessment results were in accordance with the actual disaster situation. The analysis shows that the distribution of zones with high to very high levels of river blocking is closely correlated with the topographic characteristics and actual disaster sequences of debris flows. These findings suggest that the assessment results provide scientific support for engineering planning and hazard prevention in climate-sensitive areas; thus, the presented method may serve as pertinent guidance for regional river-blocking hazard assessments of debris flows in the Parlung Zangbo Basin and beyond. Unlabelled Image • River blocking by debris flow becomes sensitive to climate and environmental change. • Debris flow runoff was determined by dynamic source and morphological connectivity. • Relations in hazard-forming process were quantified by physical models and factors. • A new step is proposed to assess regional debris flow-induced river blocking hazard. [ABSTRACT FROM AUTHOR]

Snowfall is critical in the mountainous cryosphere cycle and is vulnerable to climate change. Due to data-scarcity and strong surface heterogeneity, its information is not sufficiently revealed across the Third Pole (TP) under warming. Accordingly, this study investigated the spatiotemporal variability of snowfall and its entropy information across the TP from 1980 to 2020 based on a new high-accuracy snowfall dataset (TPHiS), which was estimated from a long-term high-resolution precipitation dataset for the TP (TPHiPr) and High Asia Refined analysis version 2 reanalysis data (HARv2) using a threshold temperature method. The results indicated that the correlation coefficient, mean bias, and root-mean-square error of the daily TPHiS were 0.77, 0.03 mm/daily, and 0.18 mm/daily, respectively, compared against in-situ observation, illustrating that this dataset performs better than other snowfall datasets. The annual mean snowfall measured 259.38 mm across the TP and experienced a slight negative trend (−0.77 mm/decade, p > 0.05). A significantly positive trend in annual snowfall was observed in the intersection of the West Kunlun, Karakoram, and Western Inner Tibet, with elevations over 5500 m. In contrast, a significantly negative trend prevailed in the Pamir, Hengduan Shan, and West and Central Himalaya intersections, especially at elevations varied from 3000 to 4500 m. Compared with other seasons, a significantly negative trend in snowfall was observed in summer (−1.94 mm/decade, p < 0.05). Change in snowfall frequency entropy was more significant than that in snowfall amount entropy. A significantly positive trend in light snowfall frequency dominated the augmentation in snowfall frequency, causing a negative trend in snowfall frequency entropy, while a substantial reduction in snowfall frequency associated with the decline in light snowfall frequency induced a positive trend in snowfall frequency entropy. The outcomes provide a finer snowfall dataset for regional cryospheric research and might inform sustainable water resource management in alpines. • A new daily snowfall dataset (TPHiS) covering the TP was estimated from the TPHiPr precipitation and HARv2 reanalysis dataset using a threshold temperature method. • The daily TPHiS (CC = 0.77, MB = 0.03 mm/daily, and RMSE = 0.18 mm/daily) performed better than other snowfall datasets. • The annual mean snowfall measured 259.38 mm across the TP, and summer snowfall exhibited a significantly negative trend (-1.94 mm/decade, p < 0.05). [ABSTRACT FROM AUTHOR]

Snowfall is a critical component of the hydrological cycle and water resources supply in mountainous areas. The snowfall regime varies according to time and space, and its uncertainties exist under climate change conditions. It is a necessary process to monitor the moisture characteristics of snowfall so as to investigate the information on snowfall, but a separate study on the snow moisture characteristics did not sufficiently describe over the Tianshan Mountains (TS). This study investigated the spatiotemporal variability of snowfall in the TS during the cold season from 1982 to 2018 based on the Weather Research and Forecasting (WRF) model simulations and analyzed moisture characteristics of snowfall using the regional moisture budget analysis. The results demonstrated that the snowfall amounted to 84.53 mm in the TS during the cold season and experienced a slight increase (P > 0.05). A significant increase in snowfall was noticed in the Eastern TS and the high-altitude regions. Western Eurasia and the Arabian Sea were primary moisture sources of snowfall, and the abundant moisture was transported by the mid-latitude westerly and the southwesterly to the interior. The anomalous cyclone over Europe transported more moisture flux to Central Asia. Meanwhile, the anomalous cyclone of Mongolia and the anticyclone in southwestern Central Asia caused a declining moisture divergence in the TS and an increase of the net moisture budget, which resulted in a snowfall and snow mass augmentation. The obtained study outcomes might improve understanding of snowfall information and provide a scientific reference for water resource management under a warming climate. • Snowfall amounted to 84.53 mm in the Tianshan Mountains during the cold season and experienced a slight increase. • Western Eurasia and the Arabian Sea were primary moisture sources of snowfall, and the abundant moisture was transported by the mid-latitude westerly and the southwesterly to the interior. • A declining moisture divergence in the Tianshan and an increase of the net moisture budget resulted in a snowfall and snow mass augmentation. [ABSTRACT FROM AUTHOR]

• The composition structure of the disaster economic resilience theory has been further developed and quantitatively verified. • The correction effect of the resilience on the economic fluctuations (secondary shock) that occurred during the recovery process has been quantitatively evaluated. • The sustainable improvement of the economic system's performance by the resilience at the end of the post-disaster recovery process has been quantitatively evaluated. • Results can provide a multi-dimensional optimization plan for improving the efficiency of post-disaster recovery and reconstruction management. Quantitative measuring disaster resilience especially dynamic economic resilience (DER) belongs to a frontier research in the past decades, which can effectively improve post-disaster economic recovery effects, reducing post-disaster loss. However, DER focuses more on the overall shape changes of recovery path, two features that commonly appear in the dynamic change process of recovery curve are also worth evaluating separately: the "secondary shock" caused by adverse factors during the recovery process and sustainable improvement of economic output at the end of recovery. Therefore, we adopt a dynamic input–output model that integrates capital damage and affected people and apply it to an extreme flood in 2016, Wuhan City, China, building the relationship between 7 recovery actions (rescue funds) and changes of two features, analyzing the impact of resilience on the dynamic recovery path features through 6 characteristic variables constructed in this paper. Results show that (1) economic resilience increases from no to actual action, the dropping rate caused by "secondary shock" decreases 30.4%, and Wuhan's economic output has achieved an improvement in sustainability of 0.088% compared to the pre-disaster level, which contributes permanently to reducing vulnerability to future disasters. (2) only 21.81% (compared to the actual scenario) of the rescue funds is needed to support 30% reduction action plus 0.02% sustainable improvement. But to support the 50% recovery action, 78.92% of the rescue funds is needed. This paper aims to provide a new perspective for the refined dynamic assessment of resilience and to prove the role of resilience in promoting short-term post-disaster recovery and long-term sustainable development. [ABSTRACT FROM AUTHOR]