As an essential part of the hydrological cycle, precipitation is usually associated with floods and droughts and is increasingly being paid attention to in the context of global warming. Analyzing ...the change trends and correlation of temperature and extreme precipitation indicators can effectively identify natural disasters. This study aimed to detect the correlation and change trends of temperature and extreme precipitation indicators in Inner Mongolia from 1960 to 2019. Panel vector autoregression (PVAR) models based on Stata software were used to detect the correlation between temperature and extreme precipitation indicators at 35 climatological stations throughout Inner Mongolia. The temperature and extreme precipitation indicator trends were analyzed using the Mann–Kendall test and Sen’s slope method. The spatial distribution characteristics of the annual precipitation and rainfall intensity were more significant in the southeast and more minor in the northwest, while an increase in the annual wet days was noticeable to the northeast. The Granger cause tests of the temperature and the extreme precipitation indicators showed a correlation between each indicator and temperature at the significance level of 1%. The temperature positively correlated with only the rainfall intensity while negatively correlating with the remaining indicators. There is no doubt that trend analysis showed significant increasing trends in rainfall intensity at all stations, which means increased risk in extreme precipitation events. By contrast, the annual precipitation and annual wet days showed significant decreasing trends, which means that the precipitation is concentrated, and it is easier to form extreme precipitation events. The study can provide a basis for decision-making in water resources and drought/flood risk management in Inner Mongolia, China.
Doubly-fed induction generator (DFIG) of wind generation system is generally located at the end of the distribution power-grid. Under the weak power grid, the grid connection of wind turbines is ...unstable, and the current quality is poor. Based on DFIG output impedance model, a stability analysis method combined with adaptive control method is proposed in this paper. The DFIG impedance model with power outer-loop is derived based on the virtual synchronous control of DFIG by using adaptive robust control method. Using generalized Nyquist criterion, the impacts of different power grid conditions and control parameters on the system stable operation under virtual synchronous control are analyzed and verified. The proposed control method in this paper is verified by experiments. The proposed control method improves the quality of grid-connected current.
Heavy metals are highly toxic elements which are persistent in the natural environment, resulting in magnification throughout the food chain, adversely affecting both human and environmental health. ...Consequently, heavy metal pollution has received widespread research attention. This review assesses the current progress in heavy metal pollution monitoring, management and mitigations, which show a lack of systematic criteria for risk evaluation. Risk assessment and multivariate analysis methods are also discussed. Assessment of risk evaluation and multivariate statistical analysis are the basic step for the treatment technologies choosing. The technique used is always site-specific, and it often combines different strategies. Only by comprehensively considering the contaminated time, the concentration and nature of the contaminant, the soil/water and site characteristics, the contaminant's availability, and the existence of specific regulations can appropriate restoration and treatment plans be formulated. Combinations of GIS and modeling appear to be most effective for analysis of heavy metal pollution risk. In recent years, many physico, chemical and bio technologies have been used to remove heavy metal pollution from water and soil, each having inherent advantages and limitations. So far, no single method is universally effective for the removal of all heavy metals. Combining different technologies can lead to greater efficiency and may provide a reasonable method to conduct inter-governmental, cross-border heavy-metal prevention and monitoring, for the control of anthropogenic pollution sources. Efficient and commercially viable scaled-up heavy metal treatment technologies will yield large benefits to human and environmental health, as well as economic output. This review provides an overview of the currently available methods, to inform researchers and other stakeholders in the prevention of heavy metal pollution of water and soil.
•- We assesses progress in heavy metal pollution monitoring, management, and mitigation.•– Combining GIS, remote sensing, and modeling appear most effective for risk analysis.•– Combining treatment technologies is more efficient than using individual methods.•- Scaled-up treatment will benefit human and environmental health and economic output.•– Understanding treatment methods will help stakeholders prevent heavy metal pollution.
Due to global warming, there evolves a global consensus and urgent need on carbon emission mitigations, especially in developing countries. We investigated the spatiotemporal characteristics of ...carbon emissions induced by land use change in Shaanxi at the city level, from 2000 to 2020, by combining direct and indirect emission calculation methods with correction coefficients. In addition, we evaluated the impact of 10 different factors through the geodetector model and their spatial heterogeneity with the geographic weighted regression (GWR) model. Our results showed that the carbon emissions and carbon intensity of Shaanxi had increased overall in the study period but with a decreased growth rate during each 5-year period: 2000–2005, 2005–2010, 2010–2015, and 2015–2020. In terms of carbon emissions, the conversion of croplands into built-up land contributed the most. The spatial distribution of carbon emissions in Shaanxi was ranked as follows: Central Shaanxi > Northern Shaanxi > Southern Shaanxi. Local spatial agglomeration was reflected in the cold spots around Xi’an, and hot spots around Yulin. With respect to the principal driving factors, the gross domestic product (GDP) was the dominant factor affecting most of the carbon emissions induced by land cover and land use change in Shaanxi, and socioeconomic factors generally had a greater influence than natural factors. Socioeconomic variables also showed evident spatial heterogeneity in carbon emissions. The results of this study may aid in the formulation of land use policy that is based on reducing carbon emissions in developing areas of China, as well as contribute to transitioning into a “low-carbon” economy.
Frequent urban flooding has caused great economic losses and casualties worldwide. Sponge cities have attracted attention as an important means of flood control and disaster reduction. This paper ...systematically and comprehensively analyzes the development of sponge campuses in China and other countries and compares classic examples of sponge campus construction. We identify the following issues in sponge campus construction: lack of appropriate numerical simulation model, low public engagement and support of sponge campuses, and a lack of standardized guidance for sponge campus construction. Based on the in-depth analysis of successful examples of sponge campus construction in developed countries, and combined with consideration of China's economic development, geographical location, and urbanization level, we suggest the future development direction of sponge campus: the development of local sponge campus models; popularization of sponge theory; improvement to public participation and experience; improve the financial system of sponge campus; and standardization of guidance for sponge campus construction and maintenance. This paper expounds on the necessity of sponge campus construction and further improves the theoretical system of sponge campuses. These results can provide theoretical support and reference for the construction or transformation of sponge campuses in colleges and universities and then promote further development of sponge campuses.
Display omitted
•This paper analyzes the development of sponge campuses in different countries.•This paper summarizes the problems existing in the development of sponge campus.•This paper proposes the development direction of sponge campus in the future.
Studies focusing on flood hazard assessment (FHA) reviews are still rare and usually approach mapping, uncertainty, spatial scale, and economic loss. Nevertheless, most of these studies only provide ...a snapshot of the current development of FHA, showing a partial view, and focusing on a limited number of selected approaches and methods. This study aims to analyze the historical development and emerging fields of FHA-related research and applies a bibliometric analysis method based on the
Bibliometrix
tool and the Web of Science (WoS) database. We refined the 4135 articles retrieved, established a dataset containing 723 articles, and downloaded the information of all articles, including journal, author, country, keywords, and abstracts. The dataset is entered bibliometric analysis model to study the development of FHA-related research from 2000 to 2020 (data as of 15 February 2021). The results show that the number of articles on FHA-related research has continued to increase and developed rapidly. The top five countries in the number of studies are China, Italy, the United States, Spain, and the United Kingdom. Compared to developed countries, the FHA-related research in developing countries lags significantly behind although it is developing rapidly. Future research is likely to focus on global change, coastal floods, compound disaster, and psycho-social aspects of flooding. Moreover, research using remote sensing and machine learning is becoming increasingly sophisticated. The purpose of this research is to provide direction for future FHA-related research and provide reference and scientific guidance for FHA-related researchers.
•The design of LID scheme combined with the control objective and waterlogging area.•SWMM was used to calculate the runoff control and pollutant control benefits.•LID based on SPC was implemented in ...a university in the old city area of Xi 'an.•LID facilities provide respectable environmental, economic and social benefits.•The case can inform the optimal selection of LID practices on campus scale.
Rapid and intense urbanization has brought a wide range of serious issues like flooding and water pollution, which have become a great concern in a lot of cities. In response to these problems, Sponge City (SPC) has emerged as a potential solution. This study utilized the Stormwater Management Model (SWMM) to simulate urban runoff and determine an optimal combination of Low Impact Development (LID) strategies for reconstructing the study area. Upon analyzing the existing rainwater drainage system and revealed that it could only meet the design return period of 2-years, and identified the vulnerable flood-prone area and the maximum overflow node. After comprehensive consideration of various factors, the sponge reconstruction scenario selected four LID facilities combination: Porous pavement, Rain garden, Sunken green belt, and Green roof. Results indicated that when P = 1-yr, 5-yr, 10-yr and 20-yr, the total runoff in the LID scenario decreased by 43.91 %, 43.93 %, 45.95 % and 47.11 %, respectively. LID facilities substantially mitigate stormwater runoff and peak flows during moderate to light rainfall events. These LID facilities prove effective in reducing pollutant concentrations (reduction rate is all over 42 %), with notable reductions in Chemical Oxygen Demand (COD) and Suspended Solids (SS). This paper offers valuable insights that can serve as a reference for the construction or renovation of SPC, shedding light on effective strategies and considerations for managing stormwater and mitigating the impact of urbanization.
Urban development and climate change have strengthened the possibility of floods and droughts in cities. In this study, we evaluated the influences of these disasters and related social damage in ...nine major basins during the past 50 years. Unusually, the following conclusions were drawn from the analysis of relevant indicators before and after urbanization: (1) agricultural loss area (flood), grain loss, and direct economic loss showed an upward trend, while other indicators showed the opposite. (2) Floods most often occur in the Yangtze River Basin (58, 26.2%), followed by the Liaohe River Basin (49, 22.2%), which is closely related to the topography and economic progress of the area. (3) The modified Mann–Kendall (MK) analysis results are consistent with the indicators trend. Finally, the regularity of the climate change and urbanization process is revealed by the migration of the standard deviation ellipse and the mean center of the four indicators. China needs to integrate urban water/drought policy development with sustainable urbanization policy development to cope with the changing natural and social environment and to minimize urban ecological risks.
Hereditary deafness is a common neurosensory disorder, and 148 non‐syndromic deafness genes have been identified to date. Gene therapy has been used to treat a variety of genetic diseases, but no ...gene therapy drug for hereditary deafness has been approved for clinical use. At present, several clinical trials of gene therapy for hereditary deafness are underway. However, few normative documents have been issued to guide the standardization of gene therapy for hearing loss, and this document is the first global gene therapy guideline for hereditary hearing loss. The guidelines were jointly developed and drafted by experienced audiologists, virologists and biologists who are vigorously involved in inner ear gene therapy research in the Hearing, Speech and Communication Subsociety of Biophysical Society of China, Audiology Development Foundation Of China and Audiology Subsociety of Jiangsu Medical Association. These guidelines cover preclinical research and clinical practice of gene therapy for hereditary deafness, including indications, key points of pre‐clinical research, patient selection criteria, pre‐clinical preparation, drug efficacy, drug safety evaluation criteria, ethical review, etc. We hope that the guidelines will promote the standardization of clinical practice related to gene therapy for hereditary deafness in China and around the world.