Impact of COVID-19 lockdown on water quality in China during 2020 and 2022: two case surges.

The COVID-19 severely affected the world in 2020. Taking the two outbreaks in China in 2020 and 2022 as examples, the spatiotemporal changes in surface water quality levels and CODMn and NH3-N concentrations were analyzed, and the relationships between the variations in the two pollutants and environmental and social factors were evaluated. The results showed that during the two lockdowns, due to the total water consumption (including industrial, agricultural, and domestic water) decreased, the proportion of good water quality increased by 6.22% and 4.58%, and the proportion of polluted water decreased by 6.00% and 3.98%, the quality of water environment has been improved significantly. However, the proportion of excellent water quality decreased by 6.19% after entering the unlocking period. Before the second lockdown period, the average CODMn concentration exhibited a "falling, rising, and falling" trend, while the average NH3-N concentration changed in the opposite direction. The correlation analysis revealed that the increasing trend of pollutant concentrations was positively correlated with longitude and latitude, and weakly correlated with DEM and precipitation. A slight decrease trend in NH3-N concentration was negatively correlated with the population density variation and positively correlated with the temperature variation. The relationship between the change in the number of confirmed cases in provincial regions and the change in pollutant concentrations was uncertain, with positive and negative correlations. This study demonstrates the impact of lockdowns on water quality and the possibility of improving water quality through artificial regulation, which can provide a reference basis for water environmental management.

Spatial-Temporal Evolution Patterns and Influencing Factors of Hotels in Yellow River Basin from 2012 to 2022

Governmental attention towards the high-quality development of the Yellow River basin has brought new development opportunities for the hotel industry. This study aims to reveal the spatial-temporal evolution patterns and influencing factors of hotels in the Yellow River Basin from 2012 to 2022, based on economic, social, and physical geographic data of 190,000 hotels in the Yellow River flowing. With the help of a GIS technology system, the spatial-temporal evolution patterns of all hotels, star hotels, and ordinary hotels were explored, respectively. Then, the significant influencing factors of these patterns were revealed by using geographic detector and Person correlation analysis. The following conclusions were drawn: (1) the overall scale of the hotel industry in the Yellow River Basin expanded year by year, achieving rapid growth from 2016, and fluctuating around 2020 due to the impact of the novel coronavirus epidemic;the overall spatial distribution had significant regional differences, showing the structural characteristics of "southeast more, northwest less”;(2) there was a great difference in the degree of spatial autocorrelation agglomeration among prefecture-level cities, and the degree of agglomeration of both the hotel industry as a whole and general hotels decreased year by year, showing a random distribution in 2022;star hotels were always distributed randomly. Additionally, a strong synergistic correlation was shown between the number of ordinary hotels and the number of star hotels in local space;(3) overall, the development of the hotel industry was significantly affected by seven factors: structural force, macro force, ecological force, internal power, consumption power, intermediary power, and external power. There were differences in the forces acting on different types of hotels, which gives a pattern recognition in-depth.

Monitoring of the Surfactants in Surface Waters in Slovakia and the Possible Impact of COVID-19 Pandemic on Their Presence

In order to keep the home and occupational environment clean and non-infectious, the consumption of cleaners and disinfectants, including cosmetics, is increasing. Excessive use of these products results in their accumulation in the aquatic environment. Conventional wastewater treatment plants are unable to effectively remove the emergent pollutants, including personal care products. This article is focused on the monitoring of the presence of personal care products in surface waters in two river basins in the Slovak Republic, in terms of the surfactant content. Ecotoxicological evaluation of the selected samples from the monitored river basins was performed by an acute toxicity test using the test organism Daphnia magna. The monitoring results indicate the presence of personal care products in the aquatic environment which poses an ecological and environmental risk. Monitoring in the Hron and Nitra river basins confirmed contamination with the surfactants, to which the measures related to the COVID-19 pandemic contributed. The content of the surfactants in personal care products is significant, and their impact on the aquatic environment is not sufficiently monitored.

INTRODUCTION FROM THE EDITORIAL TEAM

The American South has the highest rate of COVID-19 mortality relating to "unhealthy lifestyle behaviors" that persist in this region, especially among the areas where historically marginalized populations are concentrated (e.g., https://www.cdc.gov/physicalactivity/physical -activity-and-COVID-19.html,<https://www.cdc.gov/physicalactivity/data/inactivity -prevalence-maps/index.html>). Schmitz and McCreary evaluate the influence of the U.S. Army Corps of Engineers in the Apalachicola-Chattahoochee-Flint (ACF) river basin regarding the Florida v. Georgia Supreme Court case. [...]the authors note that the Florida v. Georgia case provides insight for others, particularly geographers, studying the ACF river basin or other transboundary river basins from either analytical or political perspectives.

Measuring Pollution Control and Environmental Sustainable Development in China Based on Parallel DEA Method

The purpose of this study is to explore the impact of pollution control on industrial production efficiency in 31 provinces and cities in the Yellow River and Non-Yellow River basins in China from 2013 to 2017, using the methods of the directional distance function (hereinafter referred to as DDF) and the technology gap ratio (hereinafter referred to as TGR) in parallel, while taking the industrial production sector (labor force, total capital formation, energy consumption and industrial water consumption) and the pollution control sector (wastewater treatment funds and waste gas treatment funds) as input variables. Undesirable outputs (total wastewater discharge, lead, SO2 and smoke and dust in wastewater) and an ideal output variable (industrial output value) are taken as output variables. It is found that the total efficiency of DDF in the Non-Yellow River Basin is 0.9793, which is slightly better than 0.9688 in the Yellow River Basin. Among the 17 provinces and cities with a total efficiency of 1, only Shandong and Sichuan are located in the Yellow River Basin. The TGR values of 31 provinces, cities and administrative regions are less than 1, and the average TGR value of the Yellow River Basin is 0.3825, which is lower than the average TGR value of the Non-Yellow River Basin of 0.5234. We can start by improving the allocation of manpower and capital, implementing the use of pollution prevention and control funds, improving the technical level of industrial production, improving pollutant emission, and increasing output value to improve overall efficiency performance. This study uses the parallel method, taking the industrial production department and the pollution control department as inputs, to objectively evaluate the changes in industrial production efficiency and technology gap in the Yellow River and Non-Yellow River basins, which is conducive to mastering the situation of pollution control and industrial production efficiency, and provides the reference for SDG-6- and SDG-9-related policy making.

GIS and Remote Sensing-Based Approach for Monitoring and Assessment of Plastic Leakage and Pollution Reduction in the Lower Mekong River Basin

Determination of plastic leakage sources and pathways is essential in plastic pollution mitigation. Finding ways to stem land-sourced plastic waste leakage requires understanding its sources. Spatial analysis conducted in a geographic information system (GIS) environment and remote sensing investigation uncovered insights into the distribution of plastic leakage in the lower Mekong River basin (LMRB). The main objectives of this approach were: (i) to map plastic leakage density using multi-source geospatial data;and (ii) to identify plastic leakage source hotspots and their accumulation pathways by incorporating hydrological information. Mapping results have shown that plastic leakage density was highly concentrated in urban areas with a high intensity of human activities. In contrast, the major pathways for plastic leakage source hotspots were the high morphometric areas directly influenced by facilities, infrastructure, and population. The overall efforts in this study demonstrate the effectiveness of the proposed novel method used for predicting plastic leakage density and its sources from land-based activities. It is also accomplished using multi-geospatial data with GIS-based analysis to produce a graphical model for plastic leakage waste density in each region that non-technical personnel can easily visualize. The proposed method can be applied to other areas beyond the LMRB to improve the baseline information on plastic waste leakage into the river.

Stakeholders’ Perspective on Groundwater Management in Four Water-Stressed Mediterranean Areas: Priorities and Challenges

Recent studies highlight the fragility of the Mediterranean basin against climate stresses and the difficulties of managing the sustainable development of groundwater resources. In this work, the main issues related to groundwater management have been identified from the stakeholder’s perspective in the following four representative water-stressed Mediterranean areas: the coastal aquifer of Comacchio (Italy), the Alto Guadalentín aquifer (Spain), the alluvial aquifer of the Gediz River basin (Turkey), and the Azraq aquifer (Azraq Wetland Reserve, Jordan). This has been achieved by designing a methodology to involve and engage a representative set of stakeholders, including a questionnaire to learn their point of view concerning the current management of aquifer systems and their experience with the already available tools for groundwater resource management, such as monitoring networks and numerical models. The outcome of the survey has allowed us to identify both particular and common challenges among the four study sites and among the various groups of stakeholders. This information provides valuable insights to improve the transfer of scientific knowledge from the research centers to the authorities managing the groundwater resources and it will help to plan more effective research activities on aquifer management. The proposed methodology could be applied in other aquifers facing similar problems.

Flood Risk and Exposure: The Case of the Tajuña Valley (Madrid, Spain)

This paper aims to update the exposure to flood risk in a catchment area of the Community of Madrid (Spain) linked to primary sector activities, albeit affected by the urban expansion of the capital. This research starts with the updating of the flood inventory, encompassing episodes documented between 1629 and 2020. The inadequate occupation of the territory means that floods continue to cause significant damage nowadays. It is worth highlighting the two recent floods (2019) that occurred just 15 days apart and caused serious damage to several towns in the basin. The areas at risk of flooding are obtained from the National Floodplain Mapping System, and the maximum and minimum floodable volume in the sector of the Tajuña River basin with the highest exposure to flooding has been calculated. The Sentinel 2 image in false colour (RGB bands 11-2-3, 11-8-3 and 12-11-8) and its transformation to colour properties (Intensity, Hue and Saturation) has made it possible to determine the extension of the riparian vegetation and the irrigated crops located in the alluvial plain. The SPOT 6 image with higher spatial resolution has allowed us to update the mapping of buildings located in areas at risk of flooding. Finally, based on cadastral data, a detailed cartography of built-up areas in areas at risk of flooding is provided. They affect buildings built mainly between the 1960s and 1990s, although the most recent buildings are built on agricultural land in the alluvial plain, even though current regulations prevent the occupation of these lands.

Long-Term Study of Antibiotic Presence in Ebro River Basin (Spain): Identification of the Emission Sources

Water monitoring is key to determining the presence of potentially hazardous substances related to urban activities and intensive farming. This research aimed to perform a long-term (four years) quantitative monitoring of selected antibiotics (azithromycin, enrofloxacin, trimethoprim and sulfadiazine) both in rivers and wastewaters belonging to the Ebro River basin (North of Spain). The target antibiotics were chosen on the basis of a preliminary multispecies screening. The analysis of the antibiotics was carried out by LC-MS/MS on wastewater-treatment plant (WWTP) effluent, effluents of a slaughterhouse and hospital, rivers downstream and upstream of these WWTPs, and rivers close to extensive farming areas. The ANOVA test was performed to study the significant differences between the points exposed to concrete emission sources and antibiotic concentration. The monitoring, carried out from 2018 to 2020, has been essential to illustrating the presence of the most abundant antibiotics that were detected in the Ebro River basin. Enrofloxacin has appeared in river waters in significant concentrations, especially near intensive farming, meanwhile azithromycin has been frequently detected in wastewaters.