Catchment Area Research Articles

A Decision Method for the Catchment Area of Subway Station Under the Difference of Connection Modes

A Decision Method for the Catchment Area of Subway Station Under the Difference of Connection Modes

Associations between recorded loneliness and adverse mental health outcomes among patients receiving mental healthcare in South London: a retrospective cohort study.

Loneliness disproportionately affects people with mental disorders, but associations with mental health outcomes in groups affected remain less well understood. A cohort of patients receiving mental healthcare on 30th June 2012 was assembled from a large mental health records database covering a south London catchment area. Recorded loneliness within the preceding 2 years was extracted using natural language processing and outcomes were measured between 30th June 2012 until 30th December 2019, except for survival which applied a censoring point of 6th December 2020 according to data available at the time of extraction. The following mental healthcare outcomes: (i) time to first crisis episode; (ii) time to first emergency presentation; (iii) all-cause mortality; (iv) days active to service per year; and (v) face-to-face contacts per year. Loneliness was recorded in 4,483 (16.7%) patients in the study population and fully adjusted models showed associations with subsequent crisis episode (HR 1.17, 95% CI 1.07-1.29), emergency presentation (HR 1.30, 1.21-1.40), days active per year (IRR 1.04, 1.03-1.05), and face-to-face contacts per year (IRR 1.28, 1.27-1.30). Recorded loneliness in patients with substance misuse problems was particularly strongly associated with adverse outcomes, including risk of emergency presentation (HR 1.68, 1.29-2.18) and mortality (HR 1.29, 1.01-1.65). Patients receiving mental healthcare who are recorded as lonely have a higher risk of several adverse outcomes which may require a need for higher service input.

Detecting heterogeneity of spatial accessibility to sports facilities for adolescents at fine scale: A case study in Changsha, China

Abstract It is crucial for social sustainability that adolescents have access to social sports services fairly. However, there are few research studies on requirements for sports facilities and spatial accessibility of adolescents at a fine scale. Further, identifying the heterogeneity of the relationship between spatial accessibility and other factors and their scales simultaneously would be conducive to reveal the variations of spatial accessibility effectively under the potential scale effect. This research aims to explore the heterogeneity of spatial accessibility to sports facilities at a fine scale in Changsha, China. The Gaussian-based two-step floating catchment area model is first employed to evaluate spatial accessibility. Then, multiscale geographically weighted regression (MGWR) is applied to examine the relationship between spatial accessibility and its associated factors. The mean accessibility in Yuelu District (0.158) is the highest as well, and the standard deviation (0.236) is also the highest one. Both the accessibility (0.019) and its standard derivation (0.029) in Furong District are the lowest. The results show that there is a lack of balance of spatial accessibility for the clusters with different accessibility levels distributed in the study area. Some socio-economic factors, such as housing price and nighttime light intensity, have significant impacts on spatial accessibility for adolescents with spatial and scale heterogeneity by using MGWR. Based on heterogeneous distribution and association, suggestions for promoting spatial accessibility to sports facilities for adolescents are proposed.

Flood frequency analysis using mean daily flows vs. instantaneous peak flows

Abstract. In many cases, flood frequency analysis (FFA) needs to be carried out on mean daily flows (MDF) instead of instantaneous peak flows (IPF), which can lead to underestimation of design flows. Typically, correction methods are applied to the MDF data to account for such underestimation. In this study, we first analyse the error distribution of MDF-derived flood quantiles over 648 catchments in Germany. The results show that using MDF instead of IPF data can lead to underestimation of the mean annual peak flow (MHQ) by up to 80 % and mainly depends on the catchment area but appears to be influenced by gauge elevation as well. This relationship is shown to differ for summer vs. winter floods. To correct such underestimation, different linear models based on predictors derived from MDF hydrograph and catchment characteristics are investigated. Apart from the catchment area, a key predictor in these models is the event-based ratio of flood peak to flood volume (p/V ratio) obtained by the MDF data. The p/V models applied to either MDF-derived events or statistics seem to outperform other reference correction methods. Moreover, they require a minimum data input, are easily applied, and are valid for the entire study area. The best results are achieved when the L moments of the MDF maximum annual series are corrected with the proposed model, which reduces the flood quantile errors by up to 60 %. The approach behaves particularly well in smaller catchments (<500 km2), where reference methods fall short. However, the limit of the proposed approach is reached for catchment sizes under 100 km2, where the hydrograph information from the daily series is no longer capable of approximating instantaneous flood dynamics and gauge elevations below 100 m, where the difference between MDF and IPF floods is very small.

Measuring Spatial Access of Vulnerable Population to HIV Testing Facilities in the Baton Rouge Metropolitan Statistical Area, Louisiana.

Ensuring adequate and equitable access to affordable HIV testing is a crucial step toward ending the HIV epidemic (EHE). Using the high-burden Baton Rouge Metropolitan Statistical Area (MSA) as an example, we measure spatial access to HIV testing facilities for vulnerable populations and assess whether their access would improve if eliminating a considerable barrier-costs. Locations and status (free, low-cost, and full cost) of HIV testing facilities are searched on the Internet and confirmed through a field survey. Vulnerable populations include the uninsured and people living with HIV (PLWH), disaggregated from county-level HIV prevalence data. Spatial access is computed by a normalized urban-rural two-step floating catchment area (NUR2SFCA) method. Our survey confirms that only 11% and 37% of the 103 Internet-searched HIV testing facilities are indeed free and low-cost. Making more facilities cheaper or free increases the average access of PLWH, the uninsured, and the entire population but their geographic patterns vary. Free testing facilities, clustered in Baton Rouge city, are highly accessible to 82.6%, 69.4%, and 70.2% of three population groups living in East and West Baton Rouge Parish. In comparison, making all low-cost facilities free increases access in most outlying parishes but at the cost of reducing access in East Baton Rouge Parish, leaving west Livingston, north Iberville, and east Pointe Coupee Parish with the poorest access. Making all full-cost facilities cheaper or free exhibits a similar pattern. The study has important policy implications for where and how to improve access to HIV testing for vulnerable populations.

Temporal and geographical variations in diagnostic imaging in Norway

BackgroundUnwarranted temporal and geographical variations are acknowledged as a profound problem for equal access and justice in the provision of health services. Even more, they challenge the quality, safety, and efficiency of such services. This is highly relevant for imaging services.ObjectiveTo analyse the temporal and geographical variation in the number of diagnostic images in Norway from 2013 to 2021.MethodsData on outpatient imaging provided by the Norwegian Health Economics Administration (HELFO) and inpatient data afforded by fourteen hospital trusts and hospitals in Norway. Data include the total number of imaging examinations according to the Norwegian Classification of Radiological Procedures (NCRP). Analyses were performed with descriptive statistics.ResultsMore than 37 million examinations were performed in Norway during 2013–2021 giving an average of 4.2 million examinations per year. In 2021 there was performed and average of 0.8 examinations per person and 2.2 examinations per person for the age group > 80. There was a 9% increase in the total number of examinations from 2013 to 2015 and a small and stable decrease of 0.5% per year from 2015 to 2021 (with the exception of 2020 due to the pandemic). On average 71% of all examinations were outpatient examinations and 32% were conducted at private imaging centres. There were substantial variations between the health regions, with Region South-East having 53.1% more examinations per inhabitant than Region West. The geographical variation was even more outspoken when comparing catchment areas, where Oslo University Hospital Trust had twice as many examinations per inhabitant than Finnmark Hospital Trust.ConclusionAs the population in Norway is homogeneous it is difficult to attribute the variations to socio-economic or demographic factors. Unwarranted and supply-sensitive variations are challenging for healthcare systems where equal access and justice traditionally are core values.

ПУТИ ВОВЛЕЧЕНИЯ НЕВОСТРЕБОВАННЫХ СЕЛЬСКОХОЗЯЙСТВЕННЫХ ЗЕМЕЛЬ ВЛАДИМИРСКОЙ ОБЛАСТИ В ЭКОНОМИЧЕСКИЙ ОБОРОТ

The article, using the example of the territories of the Troitsky and Novomoskovsky administrative districts (hereinafter referred to as TiNAO) of Moscow, shows the possibility of a geoecological assessment of changes in the morphometric parameters of small reservoirs. Before joining the administrative structure of the Moscow territories in 2012, the studies on the ecology of these territories was minimal. Of particular importance for monitoring the geo-ecological situation in “New Moscow», – what the conjoined territories are also called, is the fact that its area is 1,480 km2, which is 57.8% of the entire territory of Moscow.
 The subject of the study were 1402 small reservoirs registered in the territory of the TiNAO. To carry out their environmental assessment, a cluster analysis method was used, which is a universal mathematical tool for scientific research. A negative change (decrease) in the average depth of the reservoir was taken as the main parameter of the study. Based on the results of the objects’ morphometry analysis carried out at an interval of two years, data on dynamic changes in the physical parameters of reservoirs were obtained and processed. It was established that shallowing problems exist in 4.51% of the total area of reservoirs in the TiNAO. Mapping stagnant small reservoirs made it possible to visually assess the scale of the problem and identify potentially problematic areas of the TiNAO from a geoecological point of view. Using the cluster analysis, zoning of problematic water bodies was carried out. Such identification (clustering) of water bodies’ grouping made it possible to see deviations at the level of groups of small river basins, which provided a large-scale understanding of the ecological situation at the level of catchment areas of larger water bodies.

Research on the Classification of Rail Transit Stations and Passenger Flow Patterns—A Case from Xi’an, China

Transit-oriented development (TOD) has been promoted and implemented worldwide through the efficient integration of rail transit stations and land use. However, the interactions between stations and the surrounding catchment areas (CAs) are characterized by different features of the built environment and regional development. Therefore, it is necessary to develop a quantitative classification method for rail transit stations based on the built environment within a CA and to identify the passenger flow characteristics of different types of stations to develop targeted planning and design policies. In this study, Line 1 and Line 2 within the third ring road of Xi’an City were taken as the objects, and a station classification system was constructed by taking station traffic levels and different building functions within the CA as the classification factors. Secondly, indicators of the built environment, such as six different types of functions, were calculated through refined vector modeling, and 30 typical stations were typologically analyzed. Furthermore, 10 typical types—totaling 11 stations—were selected for passenger flow monitoring, and the passenger flow characteristics of the different types of stations were summarized in terms of the dimensions of stations and exits. Finally, the correlations between the indicators of the built environment and passenger traffic for different functions were quantified. This study provides a basis for the future optimization of stations and the built environment, as well as station design and management.

Exploring gestational age, and birth weight assessment in Thatta district, Sindh, Pakistan: Healthcare providers' knowledge, practices, perceived barriers, and the potential of a mobile app for identifying preterm and low birth weight.

Reliable methods for identifying prematurity and low birth weight (LBW) are crucial to ending preventable deaths in newborns. This study explored healthcare providers' (HCPs) knowledge, practice, perceived barriers in assessing gestational age and birth weight and their referral methods for preterm and LBW infants. The study additionally assessed the potential of using a mobile app for the identification and referral decision of preterm and LBW. This qualitative descriptive study was conducted in Thatta District, Sindh, Pakistan. Participants, including doctors, nurses, lady health visitors, and midwives, were purposefully selected from a district headquarter hospital, and private providers in the catchment area of Global Network's Maternal and Newborn Health Registry (MNHR). Interviews were conducted using an interview guide after obtaining written informed consent. Audio recordings of the interviews were transcribed and analyzed using NVIVO® software with an inductive approach. The HCPs had extensive knowledge about antenatal and postnatal methods for assessing gestational age. They expressed a preference for antenatal ultrasound due to the perceived accuracy, though accept practical barriers including workload, machine malfunctions, and cost. Postnatal assessment using the Ballard score was only undertaken sparingly due to insufficient training and subjectivity. All HCPs preferred electronic weighing scales for birth weight Barriers encountered included weighing scale calibration and battery issues. There was variation in the definition of prematurity and LBW, leading to delays in referral. Limited resources, inadequate education, and negative parent past experiences were barriers to referral. Foot length measurements were not currently being used. While mobile apps are felt to have potential, unreliable electricity supply and internet connectivity are barriers. The HCPs in this study were knowledgeable in terms of potential tools, but acknowledged the logistical and parental barriers to implementation.

Geographical Attributes, Distribution, and Determinants of Pelvic Organ Prolapse in Midwestern Nepal

The study investigated the geographical attributes, distribution, and determinants of pelvic organ prolapse (POP) in Nepal to comprehend the underlying factors contributing to its high prevalence in the region. Conducted in the Panchapuri municipality of midwestern Nepal, this cross-sectional study surveyed 103 married women aged 20–49 years using a semi-structured questionnaire. Participants were randomly selected from four health facility catchment areas in equal proportions. Descriptive statistics presented the data while binary logistic regression models assessed factors associated with POP. Participant allocations were mapped using ArcGIS, with shapefiles obtained from official sources. The study revealed a POP prevalence of 37.9%, with housewives exhibiting a significant association compared to businesswomen (AOR: 5.291; 95% CI: 1.046, 26.775). Constipation during pregnancy was significantly associated with POP (AOR: 9.104; 95% CI: 2.210, 37.501), while multipara women with a parity of four or more were 7.8 times more likely to have POP. Interestingly, geographical attributes like altitude, slope, and climate showed no association with POP. The findings underscore the significant association of POP with factors such as housewives, pregnancy-related constipation, and multiparity. Addressing these determinants through targeted research is vital in alleviating the burden of POP. This study emphasizes the urgent need for interventions, policies, and healthcare support, particularly focusing on maternal health and occupational well-being among rural housewives in Nepal.

Design Strategies to Improve Metro Transit Station Walking Environments: Five Stations in Chongqing, China

While transit-oriented development (TOD) has been widely adopted in urban design alongside the expansion of urban metro transit, the creation of pedestrian-friendly environments has often been overlooked during implementation. This has resulted in a lower walking advantage around metro transit stations. To address this issue and encourage walking and public transport use in metro transit station areas, this study undertook a quantitative comparative analysis of the pedestrian environment in five Chongqing metro transit station areas. The analysis focused on three key dimensions: “comprehensive evaluation”, “basic scale”, and “structural quality”. The comprehensive evaluation considered factors such as the pedestrian catchment area ratio, POI kernel density distribution, and crowd agglomeration. The basic scale dimension comprised floor area ratio, building density, pedestrian road density, and the quantity of station entrances and exits. Finally, structural quality factors included land use type mixing degree, POI function mixing degree, intersection connectivity, median street length, pedestrian route directness, and green view index. Based on these analyses, this study proposes a series of pedestrian environment design strategies including land use and transportation. The strategies for land use advocate for “developing compact and diverse land use”, “strengthening attraction of station center”, “positioning large projects on the edge”, “restricting private transportation capabilities”. The strategies for transportation consist of “increasing pedestrian road density”, “traffic calming organization”, “subdivision of road types”, and “three-dimensional pedestrian traffic system”. These strategies aim to create a more humanized and environmentally friendly pedestrian environment, proactively rise to the challenge of climate change, thereby cultivating sustainable urban development.

Explaining variation in stream fish productivity with biotic and abiotic variables across wadeable rivers in eastern North America

Abstract Biomass production is a key ecosystem process that provides insight into ecological processes such as growth, reproduction, mortality, and energy distribution. Previous studies have considered various fish response measures such as species richness, abundance, and/or biomass as response variables for river ecosystems or the productivity of particular species. However, few studies have investigated how total fish productivity of riverine systems is affected by environmental variables. Here, we identified important abiotic and biotic predictors of fish productivity in wadeable, temperate riverine systems. We investigated the relationships between total stream fish productivity and multiple abiotic and biotic variables in wadeable stream reaches across Ontario, Canada. Variance partitioning was used to evaluate the relative importance of the biotic, landscape, climatic, and geologic variables on total stream fish productivity. A modified bootstrap approach was used for the model‐selection process and to parameterise an empirical fish productivity model. We found that biotic predictors explained more variation in productivity relative to the abiotic variables. The best empirical model included day‐of‐year, growing degree days, latitude, salmonid presence/absence, species richness, and upstream catchment area. Our findings indicate that a combination of both biotic and abiotic variables can provide valuable insight into how ecological processes, such as fish productivity, differ across ecosystems. Species richness and differences in assemblage characteristics may be key determinants of the overall fish productivity in stream systems. Our model can estimate productivity from salmonid presence/absence data and total species richness, instead of fish abundance data, which require larger sampling efforts.

Abstract LB139: Disparities in oral precancerous lesion surveillance in the United States upper Midwest

Abstract Objective: To determine whether geographic representation and race of patients in a regional oral cancer surveillance program (University of Minnesota Cancer Active Surveillance Population (UMN CASP)) mirror characteristics in the corresponding National Cancer Institute (NCI) designated comprehensive cancer center catchment. Introduction: Oral cancer poses a significant public health concern that may be mitigated through lesion surveillance. Representation of patients for clinical trials throughout an NCI cancer center catchment area is a crucial goal to promote improved health outcomes. This study investigates the demographic landscape of patients with preneoplastic oral lesions seen at the CASP. Methods: Through the UMN Clinical and Translational Sciences Institute, we queried 30 International Classification of Disease (ICD) 9 and 10 codes corresponding to 120 unique mucosal oral precancerous lesion descriptors of CASP patients. Automated extraction of electronic medical record (EMR) data for 4,496 patients treated by the senior author between 2011 and 2023 identified 1,375 patients with preneoplastic lesions. The proportion of patients residing in three-digit zip code regions of Minnesota were compared to 2021 American Community Survey state population data. Additionally, race data were compared between CASP patients and the UMN Masonic Cancer Center (MCC) patient catchment data. Results: CASP patients were over-represented relative to state population distributions within the Minneapolis-St. Paul metropolitan area and surrounding suburbs (region 554 p<0.0001 and region 551 p<0.0001). Under-representation of CASP patients was observed in all western and southern border regions (regions 559 p<0.0001, 560 p<0.0001, 561 p<0.0001, 562 p=0.0037, 565 p<0.0001, and 567 p=0.0006) as well as portions of central (563 p<0.0001), northern (566 p=0.0015), and north-eastern (558 p<0.0001) Minnesota. Proportional representation was observed in several regions of central (553 and 564), eastern (550), and north-eastern (557 and 556) Minnesota. Comparisons of CASP race data revealed a higher proportion of black patients (CASP 8.59% [95% CI 7.17-10.27%] vs. MCC 7.16% [95% CI 7.14-7.17%]) and a lower proportion of Asian/Pacific Islander patients (CASP 3.74% [95% CI 2.82-4.94%] vs. MCC 5.32% [95% CI 5.30-5.34%]) relative to MCC catchment patients. White, American Indian/Alaskan Native, and mixed-race groups were proportionally represented in both data sets. Conclusions: These data show that system wide EMR searches can be implemented to identify patients in an NCI cancer center catchment area with precancerous or other at-risk conditions for cancer. Importantly, Native patients were proportionally represented in the screening program while several rural locations were under-represented. This information can instruct the expenditure of additional resources for under-represented groups and permit streamlined enrollment of patients for cancer prevention clinical trials. Citation Format: Alexander J. Dwyer, Lindsey Mortensen, Beverly R. Wuertz, Frank G. Ondrey. Disparities in oral precancerous lesion surveillance in the United States upper Midwest [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB139.

Modeling Geospatial Distribution of Peat Layer Thickness Using Machine Learning and Aerial Laser Scanning Data

Organic horizons including peat deposits are important terrestrial carbon pools, and various chemical, biological, and water exchange processes take place within them. Accurate information on the spatial distribution of organic soils and their properties is important for decision-making and land management. In this study, we present a machine learning approach for mapping the distribution of organic soils and determining the thickness of the peat layer using more than 24,000 peat layer thickness measurements obtained from field data, airborne laser scanning (ALS) data and various indices obtained from therein, as well as other cartographic materials. Our objectives encompassed two primary aims. Firstly, we endeavored to develop updated cartographic materials depicting the spatial distribution of peat layers. Secondly, we aimed to predict the depth of peat layers, thereby enhancing our understanding of soil organic carbon content. Continentality, a wet area map, latitude, a depth to water map with catchment area of 10 ha, and a digital elevation model were the most important covariates for the machine learning model. As a result, we obtained a map with three peat layer thickness classes, an overall classification accuracy of 0.88, and a kappa value of 0.74. This research contributes to a better understanding of organic soil dynamics and facilitates improved assessments of soil organic carbon stocks.

EPR24-120: A Data-Driven Approach to Increase Lung Cancer Screening Rate in the Catchment Area of an NCI-Designated Cancer Center via Community Outreach and Engagement.

EPR24-120: A Data-Driven Approach to Increase Lung Cancer Screening Rate in the Catchment Area of an NCI-Designated Cancer Center via Community Outreach and Engagement.

Delineation of Groundwater Potential Zones for Sustainable Development and Planning using AHP and GIS Techniques in the Coal Mining Province of Mahan River Catchment Area

The present research aims to address the drinking water crisis in the Mahan River catchment area resulting from the disruption of groundwater availability due to extensive coal mining. The study uses GIS-based Multi-Criteria Decision Analysis (MCDA) to map the groundwater potential of the area by analysing several factors that affect groundwater availability, including rainfall, water depth, geomorphology, geology, soil, land-cover/land-use, and topographic characteristics derived from DEM. The groundwater potential map created using the MCDA technique classified the area into low, moderate, and high groundwater potential zones. The map was validated and verified using water table depth and electrical conductivity values available in the region, indicating that it can be used to identify groundwater recharging sites. The study’s results show that about 30% of the area has high groundwater potential, and more than 45% of the area has moderate groundwater potential. The information derived from the study can be used for sustainable management and proper planning of groundwater resources in the Mahan River catchment area. Overall, the study presents a useful approach to address the groundwater depletion problem resulting from coal mining activities in the Mahan River catchment area.

Optimal site selection strategies for urban parks green spaces under the joint perspective of spatial equity and social equity

Urban park green spaces (UPGS) are a crucial element of social public resources closely related to the health and well-being of urban residents, and issues of equity have always been a focal point of concern. This study takes the downtown area of Nanchang as an example and uses more accurate point of interest (POI) and area of interest (AOI) data as analysis sources. The improved Gaussian two-step floating catchment area (G2SFCA) and spatial autocorrelation models are then used to assess the spatial and social equity in the study area, and the results of the two assessments were coupled to determine the optimization objective using the community as the smallest unit. Finally, the assessment results are combined with the k-means algorithm and particle swarm algorithm (PSO) to propose practical optimization strategies with the objectives of minimum walking distance and maximum fairness. The results indicate (1) There are significant differences in UPGS accessibility among residents with different walking distances, with the more densely populated Old Town and Honggu Tan areas having lower average accessibility and being the main areas of hidden blindness, while the fringe areas in the northern and south-western parts of the city are the main areas of visible blindness. (2) Overall, the UPGS accessibility in Nanchang City exhibits a spatial pattern of decreasing from the east, south, and west to the center. Nanchang City is in transition towards improving spatial and social equity while achieving basic regional equity. (3) There is a spatial positive correlation between socioeconomic level and UPGS accessibility, reflecting certain social inequity. (4) Based on the above research results, the UPGS layout optimization scheme was proposed, 29 new UPGS locations and regions were identified, and the overall accessibility was improved by 2.76. The research methodology and framework can be used as a tool to identify the underserved areas of UPGS and optimize the spatial and social equity of UPGS, which is in line with the current trend of urban development in the world and provides a scientific basis for urban infrastructure planning and spatial resource allocation.

Service use and glycaemic control of young people with type 1 diabetes transitioning from paediatric to adult care: a 5-year study.

Regular contact with specialist care has been linked to better diabetes outcomes for young people with type 1 diabetes (YPwT1D), but evidence is limited to population-based service usage and outcomes. This observational 5-year study sought to capture YPwT1D living in the study catchment area (covering metropolitan, regional and rural Australia) as they transitioned to adult-based diabetes healthcare services and to describe their glycaemic control and complication rates, service usage and associated factors. Records between 2010 and 2014 in a public healthcare specialist diabetes database were extracted, care processes and outcomes were described, and associations were sought between episodes of care (EOC) and potentially predictive variables. Annual cohort numbers increased yearly, but without significant differences in demographic characteristics. Each year around 40% had no reported planned specialist care, and the average number of planned EOC decreased significantly year on year. Overall, mean HbA1c levels also reduced significantly, but with higher values recorded for those living in non-metropolitan than metropolitan areas (achieving significance in 3 out of 5 years). Diabetes complication assessments were only reported in 37-46%, indicating one in five with retinopathy and hypertension affecting one in three to five young people. Findings highlight the importance of investment to address the specific needs of adolescents and young adults and demonstrate the need for better support during these vulnerable early years, particularly for non-metropolitan residents. This will entail changes to funding mechanisms, the health workforce and infrastructure, and new models of care to provide equity of access and quality of specialist care.

A hydrogeomorphic dataset for characterizing catchment hydrological behavior across the Tibetan Plateau

Abstract. Hydrologic and geomorphic processes are intricately linked within the Earth system, jointly characterizing terrestrial hydrological behaviors and biogeochemical cycles across diverse temporal and spatial scales. The Tibetan Plateau provides an ideal setting for investigating the interactions between hydrological and geomorphic processes in a largely pristine natural environment. Nonetheless, the interactions remain largely unknown due to challenging physical conditions and data limitations. This study presents the inaugural version of a hydrogeomorphic dataset encompassing 18 440 catchments across the region. The dataset comprises 18 hydrogeomorphic metrics along with, in particular, the width-function-based instantaneous unit hydrograph (WFIUH) of each catchment. We find that the peak flow of WFIUH is positively related to slope and curvature but negatively related to catchment area, perimeter, length and circularity. The relationships of time to peak with the hydrogeomorphic metrics are similar to those of peak flow but in an oppositive direction. Catchment concentration time shows a positive relationship with catchment size but a strong negative correlation with catchment slope. The validity of the derived WFIUH has been confirmed by its successful integration into an hourly hydrological model for simulating flash-flood events. Uncertainties in the WFIUH can be attributed to the resolution of the digital elevation model (DEM) and the methods employed for calculating flow velocity. The dataset is publicly available via the Zenodo portal: https://doi.org/10.5281/zenodo.8280786 (Guo and Zheng, 2023). It can contribute to advancing our understanding of catchment hydrological behaviors and can provide simple and fast-routing unit hydrograph calculation for ungauged catchments in the Tibetan Plateau and hence improve water resources management and disaster mitigation in the region and its downstream areas.

Impact of anthropogenic changes and rainfall variability on river discharge in tropical Central Africa

Abstract The objective of this study is to investigate the effects of rainfall variability and anthropogenic changes on river discharge in the Benoue and the Logone river basins over the last 7 decades (1950–2018). To achieve this goal, hydrometeorological data from these basins were analyzed using the Pettitt and Mann–Kendall tests. Our results show that negative rupture was observed in the hydrometeorological time series of these basins at the annual time step in 1970–1971. The deficits associated with this rupture are estimated at −7% for rainfall and −28% for river flows. The wet season shows similar developments. However, from the 1990s onward, there has been a significant increase in the mean annual flows of the Benoue River, which coincides with that of the rainfall during the same decade. This increase over the recent decades could also be expected in response to an increase in impervious surface area in the catchment area, which could compensate for the deficit generated by the post-1990s rainfall deficit through an increase in runoff. Since the filling of the Lagdo Dam in 1983, an increase in all ranges of minimum flow, as well as an increase in the variability of extreme flows, has been detected.