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The estuary is a critical transitional zone between freshwater and marine ecosystems, which plays a pivotal role in the preservation of biodiversity and the provision of ecosystem services. The ecological integrity of estuaries is vital in the sustainable ecosystem management and conservation. This study conducted a bibliometric analysis of estuarine ecological integrity assessment, focusing on the methodologies and the selection of relevant indicators. The methodology primarily included physical-chemical, biological, and socio-economic indicators. The evaluation's significance was systematically analyzed through various indicators in several case studies. Finally, the paper identifies ongoing challenges in assessing estuarine ecological integrity and offers several suggestions to address them. [ABSTRACT FROM AUTHOR]

Objectives: As an important part of cultural heritage, immovable cultural relics are facing increasing risks of rainstorm and flood disaster. In order to improve the capabilities of prevention on rainstorm and flood disaster for immovable cultural relics, we proposed a risk assessment method based on the theory of natural disaster risk assessment considering the seasonal variation of rainstorm and flood disaster, and took 24 national ancient sites in 18 counties in Fujian Province as an example. Methods: The regional L-moments method was used to acquire the rainfall values of various return periods in different season, and analyze the characteristics of seasonal rainstorm and flood risk. We estimated the risk from three aspects: Hazard factors, disaster formative environment and hazard bearing body of cultural heritages. The coefficient of variation method, entropy weight method and Delphi method were adopted to calculate the weight of those three aspects. Results: The results show that the seasonal difference of risk assessment results is obvious, which indicates that the assessment method is feasible. The risk of rainstorm and flood was the highest in the second quarter, followed by the first and the third quarters, and the spatial distribution of risk in different seasons was significantly different. In the first and the second quarters, the risk of rainstorm and flood was high in coastal and northern counties, and low in central counties. The risks in the third and the fourth quarters were high in the coastal areas and low in the inland areas. Conclusions: The proposed model for immovable cultural relics can well reflect the seasonal difference of rainstorm and flood risk, and is suitable for regions with large seasonal difference of rainstorm and flood disaster. The results of seasonal differences can provide scientific reference for disaster prevention and mitigation planning for immovable cultural relics. [ABSTRACT FROM AUTHOR]

Copyright of Pearl River is the property of Pearl River Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The bay ecosystem plays an important role in maintaining energy flow, material circulation, community stability and ecosystem balance. In the present study, the comprehensive evaluation model for marine ecosystem of Laizhou Bay was established by using index system method, in which, five indicators were selected including water environment, sedimentary environment, marine community, primary productivity and ecological disaster indexes. The relative importance and weight of the evaluation indexes were determined combined using analytic hierarchy process and experts consultation method. By analyzing the survey data obtained, this assessment system was applied to assess and compare the health level of Laizhou Bay in recent ten years. Results showed that the condition of Laizhou Bay was always being sub-health, the main indicators that had given adverse impact on the health level of Laizhou Bay included inorganic nitrogen, phosphate, petroleum hydrocarbon, plankton species and benthic biomass. The results of evaluation model were more sensitive to Laizhou Bay, which could identify the adverse effects of extreme events such as oil spills and typhoons, therefore, the use of interval index and environmental admissible value could avoid disadvantage concealment, information omissions and the overestimation of limit value-based assessment method effectively.

Based on a review of previous studies on urban resilience, this research paper focuses on the issue of waterlogging. It integrates resilience concepts to propose a process decomposition of urban resilience, utilizing the pressure-state-response conceptual model. A quantitative assessment model for waterlogging resilience under rainstorm conditions was developed, and three types of resilience to waterlogging disasters in Haikou were explored through a combination of game theory and cloud models. The study provides an in-depth understanding of Haikou's flood resistance capacity. It reveals that Haikou's resilience was at a moderate level during the study period, but there has been a slight decline over time. The resilience index of 2020 is approximately 2.35 % lower than in 2015. The state resilience declined sharply. Areas with high urban resilience are typically concentrated in the central area, while those with low resilience are generally located in undeveloped areas. From the perspective of indicator changes, the two indicators of per capita GDP and average rainfall exhibited the most significant downward trends. To systematically enhance Haikou's flood resistance capabilities, the paper proposes three strategies: pressure, state, and response. The research results offer detailed decision-making guidance for the construction of urban flood-resistant systems and provide scientific support for the quantification of flood resistance capacity. In recent years, urban natural disasters occur frequently, and waterlogging disaster has become one of the biggest threats faced by coastal urban area. To deal with the increasingly severe urban waterlogging disaster, improving the urban resistance is a new way to achieve future urban development. Combining the theory of waterlogging disaster and resilience based on the PSR model, the whole process evaluation framework and method of urban waterlogging disaster resilience are proposed. To obtain more reliable evaluation results, a quantitative evaluation model of urban resilience was established by using game theory and cloud model. The distribution map of urban waterlogging resilience in 2015 and 2020 was obtained by ArcGIS to identify the evolution characteristics of urban waterlogging resilience and improve the ability to effectively cope with waterlogging disasters. [Display omitted] • The PSR model is used to analyze the whole process of urban resilience. • An evaluation model of urban resilience under rainstorms is established. • Using multi-source data reflects the spatial pattern of urban resilience more accurately. • A quantitative evaluation of regional waterlogging resilience based on the normal cloud model is adopted. [ABSTRACT FROM AUTHOR]

Due to the effect of climate changes and human activities, groundwater over-exploitation and aquifer depletion have become global issues of concern. Artificial recharge of groundwater through a river has been paid more attention among a variety of artificial intervention measures. It is found that not all rivers or river reaches are suitable for artificial recharge of groundwater owing to the limitations of recharge potential by infiltration and storage capacity of the vadose zone. At present, there is still a lack of widely accepted suitability assessment methods. In this study, the Yongding River in the Beijing Plain section and the underlying aquifer are taken as the study area and the case study is carried out. Moreover, the measured data are used to verify the results. The suitability assessment model (LMBGITSC model) constructed by the index system method includes eight indexes: land use types of riverbed, sediment types of riverbed, channel width, channel topographic slope, medium types of the vadose zone, thickness of the vadose zone, specific yield of the vadose zone and horizontal permeability of the vadose zone. The results show that the suitability of groundwater recharge in the Yongding River changes from good degree to medium degree along the river flow direction (except the reaches carried out anti-seepage engineering), presenting a "step-type" evolution law. The proposed method is of good applicability and can also provide reference for similar regions.

Compound floods and derived landslide disasters are frequent in estuaries under the influence of high-intensity localized heavy rainfalls and tidal level top support.This paper proposes a comprehensive method for risk assessment and spatial migration patterns of compound flood and derived landslide disasters.Meanwhile,taking Guangzhou as the study area,it constructs the index system for risk assessment of compound floods and derived landslide disasters in the city.Additionally,the weighted comprehensive evaluation method is adopted to assess the risk of multi-source compound disasters,and the spatial risk distribution pattern of the above-mentioned three types of disasters and the migration law of the disaster risk are explored based on the standard deviation ellipse method.The results are as follows:① 52.81% areas of Guangzhou are medium-high risk and high-risk ones,and the risk of composite floods and derived landslide disasters as a whole presents the characteristics of high risk in the northeast and low risk in the southwest,among which the risk of Conghua District and Zengcheng District is higher.Thus,disaster prevention and mitigation measures should be taken to reduce the disaster risks in the above areas.② The center of gravity of the risk of heavy rainfall flooding-composite flooding-composite flooding and derived landslide hazards first moves to the southwest and then to the northeast,and the disaster risk shows a southwest-northeast distribution pattern,with the first enhanced and then gradually weakened aggregation effect of disaster risks.The results can provide a scientific basis for the risk decision-making of compound disasters and disaster prevention planning.

Immovable cultural relics，an important part of the cultural heritage，occupy a large area and are relatively difficult to protect. They have relatively high risk of damage when exposing to flood disasters. In order to improve the capabilities of prevention on food disaster for immovable cultural relics，this study proposed a risk assessment method based on the theory of natural disaster risk assessment，and took 422 National Ancient Sites（including three types：ancient sites，ancient buildings，cave temples and stone carvings）in Shanxi province as an example. We built the evaluation method about flood disaster risk for immovable cultural relics from three aspects：hazard factors，disaster formative environment and hazard bearing body of cultural heritages. The results showed that the topography of Shanxi Province presented a trend of high in the south and low in the north. In terms of spatial distribution， the risk of flooding in the south was relatively high；furthermore，there were also significant differences in time distribution. The flood risk from July to September was higher than other months，and reached the highest in July. The results of differences in the temporal and spatial distribution of flood disaster risk could provide scientific reference for disaster prevention and mitigation planning for immovable cultural relics. [ABSTRACT FROM AUTHOR]

Impacts of human activity on the sustainable development of marine fisheries have been greatly concerned, and the carrying capacity with theoretic and practical meanings has become a focused area over the past two decades. More importantly, there are few studies on the fishery resources and environment compound system. In this study, based on the investigation data in Dachen Islands during 2019–2021, we proposed the evaluation method of fishery resources and ecological environment carrying capacity (FRCC & MEECC) and analyzed the coupling coordination degree between the fishery resources and environment. The results showed that (1) the MEECC of Dachen Islands was in the critical overload state and fluctuated significantly among seasons and the winter voyage of 2021 was the worst. (2) The nekton index of Dachen Islands was basically stable, the fish eggs and juvenile index dropped markedly, and the FRCC was also critically overloaded. (3) The fishery resources and marine environment were moderately balanced. Further, the development was relatively synchronized in autumn of 2019 and 2020, while the fishery resources in spring of 2021 lagged behind the marine environment.

Copyright of Hydrogeology & Engineering Geology / Shuiwendizhi Gongchengdizhi is the property of Hydrogeology & Engineering Geology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Water environment carrying capacity (WECC) is an important index to investigate the carrying capacity of water environment to human life and production. In this study, the index system method and system dynamics method were combined to calculate the water environment carrying capacity. Zhaosutai river Tieling city control unit was chosen for deteriorated water environment and the water environment carrying capacity was evaluated and early warned. The water environment carrying capacity of Zhaosutai river Tieling city control unit is calculated from 2012 to 2035, with the maximum value of 0.7817 in 2018 and the minimum value of 0.3300 in 2013. From 2020 to 2035, it is predicted that the water environment carrying capacity of Zhaosutai river Tieling city control unit will be changed from light warning to moderate warning. Through the multi-scenario simulation of four scenarios, it can be found that it is more beneficial to improve the water environment carrying capacity to limit the social and economic development while reducing the emission of pollutants. It provides an effective scientific reference for the government to coordinate environmental protection and economic development.

The construction environment of immersed tunnel is complex, the construction organization and implementation are difficult, and the operation safety risk is high. In this paper, we introduced the establishment and application of the special risk assessment system for immersed tunnel engineering, the establishment of the safety risk assessment system in the construction stage can enhance the safety risk awareness, standardize the risk management process, and guide the scheme and plan preparation, effectively reduce the construction risk and strictly prevent the occurrence of serious accidents through qualitative and quantitative construction safety risk assessment. The practice shows that the application of risk assessment system of immersed tunnel engineering is feasible, and it can be popularized and applied in similar projects. [ABSTRACT FROM AUTHOR]

Natural disasters pose a huge risk to property insurance of the highway structures. In order to improve the risk management, reduce the losses and increase the insurance benefits, a risk assessment method for highway structures in natural disaster is proposed, in which three factors are considered including disaster-causing factors, disaster-bearing carriers and disaster-pregnant environment. The disaster-causing factors include typhoon, severe tropical storm, heavy rain, flood and other natural disasters involved in the highway property insurance. The disaster-bearing carriers are the highway slope, bridge, tunnel and pavement. The disaster-pregnant environment refers to the environmental factors affecting the probability and severity of structural accident, such as topography, landforms, hydrology and artificial structures around the highway structures. Based on the satisfaction criterion, a risk assessment matrix for the main highway structures is established, in which the risk grade is determined by combining the probability and the severity of the structural accident in disasters. The probability of the accident is assessed by a weighted analytic hierarchy process, where two levels of indicators are adopted. The first-level indicators are just the disaster-causing factors, disaster-bearing carriers and disaster-pregnant environment. The second-level indicators are the factors that affect the first-level indicators, such as the warning level of typhoon and rainstorm and the status of slope drainage system. The weights of the indicators are determined by using the expert evaluation approach after investigating more than fifty experts in the field of highway structures. The severity of the accident is graded according to the possible economic losses, that is, the insurance compensation, which is calculated from the value of the highway structure. By applying the above method, a network software platform for the risk assessment of highway structures in natural disaster was developed. In two years of operation of the platform, the risks of the highway structures under natural disasters are predicted effectively, the efficiency of the countermeasures for the risks is improved, and the profit of the highway insurance is elevated. [ABSTRACT FROM AUTHOR]

This paper developed a GIS-based spatial multi-index model for large basin-scale flood risk assessment. In terms of the risk definition proposed by the IPCC, the flood risk in the Yangtze River Basin (YRB) was classified into indexes of hazard, vulnerability, and exposure. The model systematically accounts for various flood risk indicators related to the economic, social and ecological environment of the YRB. Using the robust data space analysis and processing capabilities of ArcGIS, these flood risk indicators were superimposed and analyzed to generate an integrated flood risk spatial distribution map for the YRB. The modeling results were verified reasonably well using observation data from the YRB floods in 1998, 2008, and 2016. We found that 24.90% of the study area was at very high and high risk in 1998, and the risk in these areas decreased to 15.95% and 17.61% in 2008 and 2016, respectively. We believe that the GIS-based spatial multi-index model can be applied to other areas where basin-scale flood risk assessment is desired and contribute to further scientific research on flood forecasting and mitigation. • Develop a conceptual model for the large-scale flood risk assessment. • Integrating an index system method and a GIS-based approach. • Considering comprehensive economic, social and ecological impacts on the flood risks. • Model verification was conducted using observed floods in the Yangtze River Basin. [ABSTRACT FROM AUTHOR]