Area Southwest Research Articles

Population status of the Hamadryas baboon in and around Simien Mountains National Park (SMNP), Ethiopia

ABSTRACT This baseline study was conducted in and around Simien Mountains National Park (SMNP), Ethiopia, with the objective of investigating the population status of the Hamadryas baboon. While Hamadryas baboon populations have been extensively studied in Africa, no such study has been carried out in this extreme southwest area of their range. Within the SMNP, the Hamadryas baboon is primarily found in the southwestern, northern and eastern parts of the park. The total population was estimated using the total count method at three counting sites. Within those three sites ~495 individual Hamadryas baboons were found. The population comprised ~190 adults, 150 sub-adults, 133 juveniles, and 22 infants of indeterminate age. The study was completed in both the dry and the wet season and showed no significant change in the population or population dynamics seasonally, suggesting that the members of this resident population are the primary occupants of these locations. The age and gender diversity results indicated that there were approximately 72 adult males and 117 adult females, together with 63 sub-adult males and 87 sub-adult females, 54 male and 80 female juveniles, and 22 infants during the wet season. The Hamadryas baboon’s overall sex ratio was 1:1.65 males to females for adults, 1:1.36 for sub-adults and 1:1.46 for juveniles. This study can serve as a benchmark for tracking the population status over time and rank their conservation status in this extreme southwestern range for this species.

Visioning future transport systems with an integrated robust and generative framework

Visioning has been widely adopted in transport planning as a method to support explorations of possible future transport systems over a long time horizon. There are vast variations in how visioning is applied but given a clear association between visions and the long-time perspective, it is unclear how these processes handle uncertainty surrounding the resulting visions and their implementation. This study reflects on previous visioning processes by systematically reviewing the scientific publications on participatory visioning in passenger transport. The review identifies possible improvements contributing to a systematic approach that produces concrete visions and actions to deal with uncertainties surrounding the vision and its implementation. We address these improvements by proposing a robust and generative visioning framework, which combines the generative approach in Appreciative Inquiry (Ai) and methods to handle uncertainty in the Dynamic Adaptive Planning (DAP). The framework is illustrated in a case study of the Southwest area of the Dutch city of the Hague that involved over 50 participants in a survey and two workshops. The process produced a vision for the mobility system of the area, a set of measures to realize it (i.e. pathways), and concrete actions to ensure that the pathways are robust against different futures that can affect the implementation. The approach can help planners, policymakers, and researchers in designing a visioning process that helps participants to better appreciate the temporal dimension of the visioning process and improves their awareness regarding the need to safeguard policy interventions against possible impacts of (un)certain future events.

Prevalence of Missed Opportunities for Immunization and Associated Factors in Urban and Rural Areas of Southwest, Nigeria

Purpose: The study determined and compared the prevalence of missed opportunities for immunization among children aged 12-23months in urban and rural areas of southwest, Nigeria. The study identified and compared the associated factors (cultural, religious, ethnic, political and economic).
 Methodology: This cross -sectional study was carried out among mothers of children aged 12-23 months, community and opinion leaders in urban and rural areas of southwest, Nigeria. The data was collected using semi structured questionnaire, focus group discussion and in-depth interview guides.
 Findings: The prevalence for missed opportunities for immunization was 9.6% with 11.8% in urban as compared with 7.5% in rural areas. The dose specific prevalence of missed opportunities for immunization in rural areas was highest for BCG, HBV0 and OPV0 but lowest for BCG and OPV0 in urban areas. The reasons given in both areas were non-availability of vaccines, long wait time, unscheduled visits, child brought to facility ill but not vaccinated, and distance from the facilities. After controlling for confounders, child factors (age of the child, place of delivery), socio-economic characteristics (mothers and fathers educational and occupational status) were significantly associated with missed opportunities for immunization. Most of the participants of the qualitative survey believed immunization is important as it prevents children from diseases. There were divergent views in both areas on traditions, cultures, and customs as associated factors for missed opportunities for immunization. Government is involved in immunization as reported by participants in both areas.
 Conclusion: The study concluded that missed opportunities for immunization is prevalent in both areas and reasons were non-availability of vaccine, unscheduled visits, long wait time and distance from facilities. Parent socioeconomic characteristics, child’s age, place of delivery and mothers receiving immunization messages were the factors associated with missed opportunities for immunization.
 Recommendation: There is a need for improvement of quality of interventions and advocacy to the government for continual support for immunization to reduce missed opportunities for immunization.

Spatiotemporal dynamics and potential restoration of mangroves in Circum-Xinying-Bay region, Hainan Province, China

Mangrove forests play an important role in absorbing carbon, filtering pollution, and protecting coastal residents from storms. However, mangrove forests are most susceptible to human interference and suffer more than one-third of losses globally. Therefore, quantifying their spatial-temporal changes and identifying their potential distributions are necessary for protection, restoration, and management. We first mapped and analysed the spatial-temporal changes in mangrove forests from 1993 to 2021 in the Xinying-Bay region (XYB), Hainan Province, China. Then, we predicted suitable habitats for mangrove forests by using the maximum entropy (MaxEnt) model based on mangrove distribution data for 2021 and related environmental data for the Circum-Xinying-Bay region (CXYB). The results show remarkable changes in mangrove forests in the XYB from 1993 to 2021, with the loss rate reaching 56 ha/y from 1998 to 2002. The MaxEnt model performs well, with the curve (AUC) extending beyond 0.9. Water quality and topography determined the distribution of mangrove forests, with the total contribution exceeding 65%. The six most important influential factors were salinity, DEM, precipitation in the driest quarter, pH, isothermality, and winter sea surface temperature. The area of mangroves highly suitable in the CXYB is approximately 3880 hm2 and is mainly located in the town of Xinzhou, the northeast area of the town of Mutang and the southwest area of the town of E'man. This suggests that areas prioritized for protection should include the northern and western areas of Xinzhou, northeastern areas of Mutang, and northern and western areas of E'man. These findings provide further understanding of mangrove distribution and can guide mangrove restoration and management.

Distribution of 222Rn and CO2 across faults and its origin in Wayang Windu geothermal area, West Java - Indonesia

As a geogenic gas, 222Rn (radon) has been widely utilized to infer permeability zones in some geological settings such as fault zones, volcanic and geothermal areas. In this study, soil 222Rn was measured in Wayang Windu geothermal area to infer the relation between fault and permeability. In addition, measurement of soil CO2 and its δ13C composition were also performed to infer transport mechanism and the origin of soil CO2. The high and anomaly soil 222Rn, i.e., above 8,500 Bq/m3, were found in the south - southwest area and related to Pejaten Fault, Banjarsari Fault and Cibitung Fault. In contrast, low soil 222Rn was found in the northern area, where several highly productive geothermal wells are located. The high and anomaly soil CO2 concentrations were also found in a relatively similar area with high 222Rn, but not closely related to the fault structures. Furthermore, the δ13C composition showed that the origin of soil CO2 in the area was magmatic, biogenic and atmospheric. Based on the 222Rn/CO2 values and its δ13C compositions, the mechanism of 222Rn transport was interpreted as independent from CO2 as carrier gas.

Changes in Notified Incidence of Pulmonary Tuberculosis in China, 2005–2020

ObjectiveTo evaluate the trend of notified incidence of pulmonary tuberculosis (PTB) in China at different periods by population and region and to explore the effect of TB prevention and control in recent years. MethodsUsing pooled data on TB cases reported by the TB Information Management Reporting System (TBIMS) from 2005 to 2020, we calculated the annual percentage change (APC) using the Joinpoint regression model. ResultsFrom 2005 to 2020, a total of 16.2 million cases of PTB were reported in China, with an average notified incidence of 75.5 per 100,000 population. The age standardization rate (ASR) continued to decline from 116.9 (/100,000) in 2005 to 47.6 (/100,000) in 2020, with an average annual decrease of 5.6% [APC = –5.6, 95% confidence interval (CI): –7.0 to –4.2]. The smallest decline occurred in 2011–2018 (APC = –3.4, 95% CI: –4.6 to –2.3) and the largest decrease in 2018–2020 (APC = –9.2, 95% CI: –16.4 to –1.3). From 2005 to 2020, the ASR in males (159.8 per 100,000 in 2005, 72.0 per 100,000 in 2020) was higher than that in females (62.2 per 100,000 in 2005, 32.3 per 100,000 in 2020), with an average annual decline of 6.0% for male and 4.9% for female. The average notified incidence was the highest among older adults (65 years and over) (182.3/100,000), with an average annual decline of 6.4%; children (0–14 years) were the lowest (4.8/100,000), with an average annual decline of 7.3%, but a significant increase of 3.3% between 2014 and 2020 (APC = 3.3, 95% CI: 1.4 to 5.2); middle-aged (35–64 years) decreased by 5.8%; and youth (15–34 years) decreased by an average annual rate of 4.2%. The average ASR in rural areas (81.3/100,000) is higher than that in urban areas (76.1/100,000). The average annual decline in rural areas was 4.5% and 6.3% in urban areas. South China had the highest average ASR (103.2/100,000), with an average annual decline of 5.9%, while North China had the lowest (56.5/100,000), with an average annual decline of 5.9%. The average ASR in the southwest was 95.3 (/100,000), with the smallest annual decline (APC = –4.5, 95% CI: –5.5 to –3.5); the average ASR in the Northwest China was 100.1 (/100,000), with the largest annual decline (APC = –6.4, 95% CI: –10.0 to –2.7); Central, Northeastern, and Eastern China declined by an average of 5.2%, 6.2%, and 6.1% per year, respectively. ConclusionsFrom 2005 to 2020, the notified incidence of PTB in China continued to decline, falling by 55%. For high-risk groups such as males, older adults, high-burden areas in South, Southwest, and Northwest China, and rural regions, proactive screening should be strengthened to provide timely and effective anti-TB treatment and patient management services for confirmed cases. There is also a necessity to be vigilant about the upward trend of children in recent years, the specific reasons for which need to be further studied.

Formation Evaluation of Bahariya Groundwater Aquifer Using Nuclear Logs at the Southwest area of Bani Sweif, Upper Egypt, (A Case Study)

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Using MaxEnt Model to Predict the Potential Distribution of Three Potentially Invasive Scarab Beetles in China.

A hot topic in recent years is the prediction of the potential distribution of possible invasive insects. China is facing a great challenge due to invasive insects. Scarab beetles are a highly diverse group, and many of them are well-known invasive insects. Here, in order to prevent the invasion of scarab beetles in China, we screened the invasive insects globally and obtained a preliminary database of quarantine or invasive scarab beetles. From the obtained database, we selected the top five species (Popillia japonica, Heteronychus arator, Oryctes monoceros, Oryctes boas and Amphimallon majale) to discuss and analyzed the potential distribution of three species that have not invaded China by using the MaxEnt model. The prediction results show that every continent has potential distribution areas for these species. Specifically within China, Popillia japonica and Amphimallon majale were mainly concentrated in east central regions and Heteronychus arator and Oryctes boas were mainly distributed in the southwest areas, while Oryctes monoceros has no suitable area. Notably, Yunnan, Hunan, Jiangxi and Zhejiang province had a high risk of invasion. In general, local agriculture, forestry and customs departments in China should pay more attention to monitoring for the prevention of infestation by invasive insects.

Predicting the Temperature Field of Hot Dry Rocks by the Seismic Inversion Method

Hot dry rocks, as clean and abundant sources of new energy, are crucial in the restructuring of energy. Predicting the temperature field of hot dry rocks is of great significance for trapping the target areas of hot dry rocks. How to use limited logging data to predict the temperature field within a work area is a difficulty faced in hot dry rock exploration. We propose a method to predict the hot dry rock temperature field (using seismic inversion results). The relationship between porosity and transverse wave velocity was established with petrophysical modeling. The difference in porosity calculated from the density and transverse wave velocity was incorporated in the seismic inversion results to find the thermal expansion and predict the temperature field. We applied the method to predict the temperature of hot dry rocks in the Gonghe Basin. The results showed that the temperature in the northeast work area was higher than in the southwest area at the same depth, and a depth of 150 °C of the hot dry rock reservoir was shallower. The thermal storage cover was analyzed from the geological stratigraphic data of the Gonghe Basin. The thermal storage cover in the northeastern part was thicker than in the southwestern part and had better thermal insulation, which is consistent with the prediction of the temperature field.

Current and paleoclimate models for an Atlantic Forest kissing bug indicate broader distribution outside biome delimitations

IntroductionRhodnius domesticus is a kissing bug with known occurrence around the Atlantic coast of South America and is considered to be the only endemic species of the Atlantic Forest for the Rhodniini tribe. In this study, we aimed to indicate the species trends in possible distribution in the current and paleoclimate scenarios from the last glacial maximum (LGM).MethodsWe revised R. domesticus distribution information and created ecological niche models (ENMs) between the current time and Pleistocene end scenarios for the study regions. Models were built and validated using Maxent, KUENM, and ENMeval packages in R and ArcMap. We considered the models' uncertainty when calculating the average model variance and using mobility-oriented parity (MOP) analyses to indicate extrapolation risk areas in transfer scenarios.ResultsWe found 44 different geographical species records, and our current time models indicate suitable areas in coastal regions of the Atlantic and surrounding locations in higher and lower latitudes. Paleoclimate models indicate general suitability in coastal regions and change in suitability in the interior region through time.DiscussionOur revision and ENMs indicate two main points: Despite the fact that R. domesticus records are spatial and time concentrated in some coastal regions of the Atlantic Forest, species could have a broader distribution area, including regions outside the biome delimitations in northeast and southwest areas of South America. Paleodistribution models indicate species broader distribution in Atlantic Forest-related areas in LGM and northern interior regions of South America from late Pleistocene to the current times. In glaciation scenarios, continental shelf distribution was relevant and species' different connectivity routes with other biomes may be developed after LGM.

Temporal and Spatial Distribution, Utilization Status, and Carbon Emission Reduction Potential of Straw Resources in China

Temporal and Spatial Distribution, Utilization Status, and Carbon Emission Reduction Potential of Straw Resources in China

Landslide Susceptibility mapping using random forest and extreme gradient boosting: A case study of Fengjie, Chongqing

Landslide susceptibility analysis can provide theoretical support for landslide risk management. However, some susceptibility analyses are not sufficiently interpretable. Moreover, the accuracy of many research methods needs to be improved. Therefore, this study can supplement these deficiencies. This study aims to research the evaluation effects of random forest (RF) and extreme gradient boosting (XGBoost) classifier models on landslide susceptibility, and to compare their applicability in Fengjie County, Chongqing, a typical landslide‐prone area in southwest of China. Firstly, 1624 landslides information from 1980 to 2020 were obtained through field investigation, and a geospatial database of 16 conditional factors had been constructed. Secondly, non‐landslide points were selected to form a complete data set and RF and XGBoost models were established. Finally, the area under the ROC curve (AUC) value, accuracy, and F‐score were used to compare the two models. The results show that even though both classifiers have a highly accurate evaluation of landslide susceptibility, the RF model performs better. In comparison, the RF model has a higher AUC value of 0.866, and its accuracy and F‐score are approximately 2% higher than XGBoost. The land use, elevation, and lithology of Fengjie County contribute to the occurrence of landslides. This is due to human engineering activities (such as land reclamation, and housing construction) resulting in low slope stability and landslides in widely distributed sandstone, siltstone, and mudstone layers owing to their low permeability and planes of weakness.

Understanding the Distribution Laws of In Situ Stress in Mines Based on Global Positioning System Data and Numerical Simulation Analysis

To ensure safe exploitation of the Muduchaideng Mine, we use a numerical simulation to invert the in situ stress field based on observation data from GPS stations, investigate differences in movement velocities at different locations, and analyze the lefthanded movement in the area around the wellfield. The relationship between the difference in motion velocity and the in situ stress field was explained through theoretical analysis. The law of in situ stress distribution was studied using data collected from the surrounding mines, and a regression equation as well as the relationship between the magnitudes of the three-way stresses was obtained. The inversion results were consistent with the measured data, indicating that inversion of the in situ stress field was accurate under the conditions found in the intact Ordos block. Additionally, the influence of tectonic stress on the key layer was larger than that on the bedrock of the coal seam roof, and the energy accumulated in the key layer was higher. The stress concentration coefficient of the key layer was similar to the variation law of the coal seam thickness. Therefore, the southwest area of the wellfield with a thicker coal seam is the key area for impact ground pressure prevention and control.

Geographic Information Systems (GIS) to Assess Dental Caries, Overweight and Obesity in Schoolchildren in the City of Alfenas, Brazil.

Childhood-related obesity and overweight are increasing concerns for the health and well-being of children. Dental caries (decay) is the most prevalent oral disease during childhood, and several studies have suggested that nutritional status and dental caries are associated in children. Therefore, this study aimed to determine the geographic distribution of childhood overweight/obesity and dental caries in a medium-sized Brazilian city. This cross-sectional study was conducted with 269 children of both genders enrolled in four public schools in the city of Alfenas. The children were clinically examined to assess cavitated dental caries and nutritional status (overweight and obesity). In addition, the GIS was used for the geospatial clustering analyses. A heat map was created by the Kemel method to estimate the concentration of the outcomes. The cavitated dental caries and overweight/obesity were also pointed out by dots on the map. However, of the 269 children, 118 were boys (43.87%) and 151 were girls (56.13%). One hundred fifty-seven children (58.4%) were classified as having "non-cavitated caries," while 112 (41.6%) were classified as having "cavitied caries." In the nutritional status assessment, 204 children (75.84%) were classified as "eutrophic," while 65 children (24.16%) were classified as "overweight/obesity," A geographical correlation of dental caries with overweight/obesity may exist in the northeast and southwest areas. In conclusion, a geographical concordance between the dental caries and the occurrence of overweight/obesity among the schoolchildren from Alfenas may exist in some areas. Future studies are necessary.

Elucidating pollution characteristics, temporal variation and source origins of carbonaceous species in Xinxiang, a heavily polluted city in North China

In order to understand temporal variations, sources origins of carbonaceous components in Xinxiang, an industry city in North China, high time resolution of OC and EC were observed from March 2021 to February 2022. The results illustrated annual average OC and EC concentrations were 5.76 ± 3.65 and 0.83 ± 0.56 μg m−3, respectively. Obvious seasonal and monthly fluctuations of carbonaceous components were observed with high values in cold seasons and low levels in warm seasons. Meanwhile, diurnal variation patterns of carbonaceous species illustrated temporal evolution of boundary layer height (BLH) and variation in emission intensity strongly affected carbonaceous component levels. In addition, obvious correlations between OC and EC (p < 0.001) were found with higher correlation coefficient in autumn, demonstrating they were be likely to originate from similar sources or POC contributed more to OC. The minimum R squared (MRS) method was adopted to calculate second organic carbon (SOC) concentration, represented 52%, 53%, 33%, and 52% of OC in spring, summer, autumn, and winter, respectively. Moreover, two different formation pathways (photochemical oxidation and heterogeneous reactions) of SOC were found in diverse seasons. Furthermore, nonparametric wind regression (NWR) method and potential source contribution function (PSCF) showed the sources from southeast, southwest, and northwest areas were considered as important contributors of carbonaceous species in Xinxiang. This work elucidates the significance of strict control precursors of carbonaceous components and the pressing requirements for coordinated inter−regional prevention and control of air pollution for further improving air quality.

Analyzing Spatial Trends of Precipitation Using Gridded Data in the Fez-Meknes Region, Morocco

The aim of this paper was to present a precipitation trend analysis using gridded data at annual, seasonal and monthly time scales over the Fez-Meknes region (northern Morocco) for the period 1961–2019. Our results showed a general decreasing trend at an annual scale, especially over the mountain and the wetter parts of the region, which was statistically significant in 72% of the grid points, ranging down to −30 mm per decade. A general upward trend during autumn, but still non-significant in 95% of the grid points, was detected, while during winter, significant negative trends were observed in the southwest (−10 to −20 mm per decade) and northeast areas (more than −20 mm per decade) of the region. Spring rainfall significantly decreased in 86% of the grid points, with values of this trend ranging between 0 and −5 mm per decade in the upper Moulouya and −5 to −10 mm per decade over the rest of the region (except the northwest). At a monthly time scale, significant negative trends were recorded during December, February, March and April, primarily over the northeast Middle Atlas and the northwest tip of the region, while a significant upward trend was observed during the month of August, especially in the Middle Atlas. These results could help decision makers understand rainfall variability within the region and work out proper plans while taking into account the effects of climate change.

BADI: A NOVEL BURNED AREA DETECTION INDEX FOR SENTINEL-2 IMAGERY USING GOOGLE EARTH ENGINE PLATFORM

Abstract. Forest fires are natural events that occur in numerous ecosystems worldwide and cause significant damage to human, ecological and socio-economic factors. It is also crucial to obtain useful information on the distribution and density of burned areas on large scale. An efficient way to map large regions is through remote sensing (RS). Nevertheless, the complex scenario and similar spectral signature of features in multispectral bands can lead to many false positives, making it difficult to extract the burned areas accurately. Multispectral data from Sentinel-2 satellite images allow the development of novel burned area indices, as more spectral data is recorded in the Red-Edge region. This research aims to develop a new burned area detection index (BADI) at 20 m spatial resolution in the google earth engine platform to detect the wildfire-affected areas in southwest of Iran using Sentinel-2 satellite imagery. The BADI spectral index has been specially designed to take benefit of the Sentinel-2 spectral bands and use a spectral combination of bands that are reasonable for post-fire burned regions detection. The final results indicated that the proposed index by applying a post-processing stage works well in the case of the study area to identify the burned areas. At the same time, it can satisfactorily suppress the complicated and irrelevant changes in the scene. Furthermore, the BADI index is rapid and can provide the burned areas map in near real-time. According to the Copernicus Emergency Management Service (EMS) reference data, maps of the burned areas were produced with a kappa coefficient of 0.92 and an overall accuracy of 92.15%, which demonstrated a good result in comparison to similar spectral indices.

Identification of Potential Landslide Hazards Using Time-Series InSAR in Xiji County, Ningxia

Potential landslide identification and monitoring are essential to prevent geological disasters. However, in mountainous areas where the surface gradient changes significantly, the leveling effect is not completely removed, affecting the deformation results. In this paper, the SBAS-InSAR and PS-InSAR time-series processing methods were combined to interfere with the SAR image data of the ascending orbit in the southern mountainous area of Ningxia and its surrounding regions. Based on the obtained surface deformation monitoring results and optical images, landslide hazard identification was successfully carried out within the coverage area of 3130 km2 in Xiji County. The results show that the whole study area presented a relatively stable state, most of the deformation rates were concentrated in the range of 0 mm/a to −10 mm/a, and the deformation in the southwest area was larger. A total of 11 large potential landslides (which were already registered potential danger points of geological disasters) were identified in the study area, including three historical collapses. The landslide identification results were highly consistent with the field survey results after verification. The timing analysis of the typical landslide point of the Jiaowan landslide was further carried out, which showed that the Jiaowan landslide produced new deformation during the monitoring time, but it was still in a basically stable state. It can do a good job in disaster prevention and reduction while strengthening monitoring. The results of this study have a guiding effect on landslide prevention and mitigation in the mountainous areas of southern Ningxia.

Pollution Characteristics and Health Risk Assessment of Heavy Metals in PM2.5 of Different Air Masses During Heating Season in Tianjin

In order to explore the pollution characteristics and health risks of heavy metals in PM2.5 in Tianjin, heavy metal samples (Pb, Cd, Cr, As, Zn, Mn, Co, Ni, Cu, and V) in PM2.5 were analyzed from November 2020 to March 2021 using the Xact-625 heavy metal online analyzer. The spatial and temporal distribution characteristics were analyzed using the HYSPLIT model, and the health risks of heavy metals were analyzed using the US EPA risk assessment model. The results indicated that the average total concentration of the 10 heavy metal elements was (261.56±241.74) ng·m-3, among which the concentrations of Cr ［converted Cr(Ⅵ)］ and As were higher than the annual average limit of the National Ambient Air Quality Standard (GB 3095-2012). According to the back trajectory results, the medium-distance transmissions from northwest areas (NO.1), the long-distance transmissions from northwest areas (NO.2), the transmissions from southwest areas (NO.3), and the transmissions from northeast areas (NO.4) were the major sources in Tianjin City. The heavy metals of different air masses presented different pollution characteristics and health risks; the concentration of PM2.5, the total concentration of the 10 heavy metal elements, and the total carcinogenic risk of the five heavy metal elements of the NO.3 air mass were the highest, whereas the total non-carcinogenic risk of the 10 heavy metal elements of the NO.2 air mass was higher than that of the other two air mass. The health risk assessment showed that Mn posed non-carcinogenic risks to children, and Cr and As presented carcinogenic risk. Meanwhile, Cd of the NO.3 air masses also presented carcinogenic risk.

Distribution Characteristics and Pollution Risk of Heavy Metals in River Sediment of Suzhou Water Network Area, China

The average contents of the heavy metals Cd, Cu, Cr, As, Ni, Pb, and Zn in the sediment of sampling points in the Suzhou water network area were 1.4, 127.4, 83.2, 18.2, 51.7, 145.1, and 350.7 mg·kg-1, respectively, which were 13.7, 5.7, 1.1, 1.7, 1.9, 5.5, and 5.6 times the background values, respectively. The proportions of points exceeding the risk screening values of the GB 15618-2018 standard were 100.0%, 97.3%, 38.4%, 83.6%, 97.3%, 90.4%, and 100.0%, respectively. The pollution degree of single heavy metal elements was evaluated using the improved ground accumulation index method. The pollution degree of the seven heavy metal elements in the sediment of the Suzhou water network area was in the order of Cd>Cu>Pb>Zn>As>Cr>Ni. Among them, Cd showed extremely strong pollution, Cu and Pb showed intense to extremely strong pollution, Zn showed strong pollution, As showed moderate to intense pollution, and Cr and Ni showed moderate pollution. Cd, Pb, Cu, and Zn in the sediment samples of the ancient city area, northwest area, southwest area, and east area were the heavy metal elements with high pollution contributions. The potential ecological risk degree of heavy metals was ranked as northwest>southwest>ancient city area>east. Correlation analysis and principal component analysis showed that Cd, Cu, Cr, As, Ni, Pb, and Zn may have come from anthropogenic factors such as tail gas emissions, the use of chemical fertilizers and pesticides, and the pollutant emissions of the electronic manufacturing industry.