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Mine survey is an important part of the ecological restoration design of an abandoned open-pit mine because it gives precise survey data for mine management. Unmanned aerial vehicle (UAV) photogrammetry technology is applied to mine 3D modeling and earthwork calculation to tackle the problems of high cost, low efficiency, and high labor intensity in traditional manual field mine surveys. Using the abandoned quarries in Baitu, Suzhou City, as the study area, 82 ground control points were set up, and massive elevation data of the ground was obtained using a Dajiang spirit 4 RTK UAV for aerial photography and extracted from a 3D model created with Context Capture software, while a digital orthophoto image of the study area was created. The earthwork volume is calculated using the square grid method. UAV photogrammetry has a considerably higher efficiency than typical manual field measurement results, and it meets the precision criteria of mine geological environment assessment. According to the findings, UAV photogrammetry technology has a promising future in mine geological environment monitoring and ecological environment repair.

Coal-bearing fractured aquifer is regarded as one of the most dynamic mine water inrush sources, and after pumping and treating, it can be used as a water supply for coal mine production, coal preparation plant, rural irrigation, and even reserved drinking water source. Hence, this study focuses on the hydrochemical characteristics, ion source, and water quality evaluation with respect to drinking and irrigation of the coal-bearing fractured aquifer in Dingji coal mine, Huainan coalfield, China. Descriptive statistics and hydrochemical classification diagrams including the Piper diagram and Chadha rectangular diagram were carried out to depict the hydrochemical characteristics and facies. The water quality of the aquifer was assessed for irrigation and drinking purposes using the WHO threshold value, water quality index (WQI), SAR, % Na and RSC. Hydrochemical formation mechanism and solute origin of major ions were explained by Gibbs diagram, bivariate diagrams, and multivariate statistical analysis. The results show that the dominant hydrochemical facies are the Cl-Na type and the HCO3-Na type. The sequence of ions is Na+ > Ca2+ > Mg2+ for cations, and HCO3‑ > Cl- > SO42- > CO32- for anions. The main solute sources are controlled by various factors including the dissolution of halite, sulfate, and carbonate rocks, the weathering of silicate, and cation exchange. Water quality assessment based on WQI suggests that none of the samples fall under the excellent category, even 32.5% is not suitable for direct drinking. Meanwhile, the samples of the aquifer are generally unsuitable for irrigation. Before utilization for irrigation and even drinking, appropriate water treatment should be applied to guarantee its security during usage.

Jiagou district, located in Northern Anhui Province, China, has been taken as an agriculture demonstration base for several decades, but limited hydrochemical work has been conducted on the water resources. The objective of this research was to understand the controlling processes of hydrochemical evolution and the water quality for drinking and irrigation. Twenty-seven samples of surface water and groundwater have been collected and analysed for major ions. Although the values physicochemical parameters are subjected of spatial fluctuation in different water resources, calcium and bicarbonate is still the dominant ion in the cations and anions, respectively. The values of all the parameters are within the WHO maximum permissible limit for inhabitant drinking. The predominant water type is Ca-Mg-HCO3 and Ca-HCO3. The hydrochemical methods (Gibbs diagram, Mg/Na and HCO3/Na versus Ca/Na diagram and ion ratios) suggest that rock-water interactions furnish the dominant major ion sources of the samples. Carbonate dissolution, silicate weathering and ion exchange have the predominant contribution to the origin of chemical solutes, as well as a slight function of halite dissolution. The USSL and Wilcox diagram reveal that all the samples have low salinity and low sodium water. It is of good quality suitable for irrigation, and it can be used for irrigation of most crops on most soils with less negative impacts.

The shallow groundwater around abandoned quarries is important resource for local industry and agriculture. In this study, 27 representative groundwater samples were collected from Fuli abandoned quarries area. The hydorchemical data were analyzed to reveal its geochemical mechanisms and groundwater quality. The groundwater is weakly alkaline in nature. The content of cations follow the trend: Ca2+ >Mg2+ >Na+ >K+, and anions follow the order: HCO3->SO42- >Cl->F-. The Ca2+ and HCO; are two leading ions, 96.30% of Ca2+and 100% of HCO3- have exceed desirable limit recommended by WHO. The groundwater is controlled by Ca-HCO3 and Ca.Mg-HCO3 type as main facies, Ca-HCO3.SO4 as secondary facies. The chemical composition is mainly controlled by dissolution of carbonate minerals, among which calcite is the leading mineral. Recharging analysis based on stable isotope concluded that atmospheric precipitation is the main recharge source of groundwater and influence of evaporation is relatively weak. The Standard US Salinity Laboratory classification shows that all the samples distributed in category C2-S1. Combined with the SAR, %Na, RSC, PI and Wilcox diagram, the groundwater is suitable for irrigation purpose. The outcomes provide a better understanding of hydrochemical mechanism of groundwater around abandoned quarries, and it will promote integrated management of groundwater. [ABSTRACT FROM AUTHOR]

The heavy metals of soil around Qianling abandoned cola mine, Northern Anhui province, China has exceeded local background values, posing a serious threat to human health. The enrichment factor (EF), Pollution load index (PLI) and human health risk model (USEPA) were applied to determine the pollution characteristics and risk of heavy metals in soil in this study. A total of 32 samples were collected from topsoil (0-10cm). Compared with the Anhui province background values, Zn and As are the most prominent polluted, followed by Pb. The Qianling abandoned coal mine are at high contaminated and severely contaminated degree, accounting for enrichment of Zn and As. For Non-carcinogenic risk, the heavy metals would not cause risk on adults, but risk of children cannot be ignored, and oral ingestion are the primary way. For carcinogenic risk, the heavy metals would cause risk on both adults and children. Moreover, oral ingestion is the main expose pathway for adults, and inhalation via nose and mouth and dermal contact are the insignificant pathway for children. The outcome of this study provide a better understanding and guidance for pollution control and human health. [ABSTRACT FROM AUTHOR]

Heavy metals in soils have severe effects on human health and ecosystem. The accurate pollution assessment and quantitative source analysis are significance for the prevention on soil. In this study, a total of 40 topsoil (0-15cm) samples were collected from 4 different functional areas in the study city and the content of 7 heavy metals were determined. This study use Kriging method to analysis spatial distribution. The Nemrow comprehensive pollution, Pollution load and Potential ecological hazard indexes were applied to assess the level of pollution and ecological risk, and positive matrix factorization(PMF) are conducted to source apportionment. The Pb, Cd and As are the most widely contaminated elements. The study area were suffered from moderate-severe pollution and moderate ecological risk, showing the decreasing order: industrial areas > business areas > residential areas > administrative areas. Four sources were apportioned, which were industrial activities (40.20%), atmospheric dustfall (23.23%), transportation (19.16%) and motor vehicle emission (17.39%). The outcomes of this research can serve as a basis for heavy metal treatment for government and will help in securing in city environment. [ABSTRACT FROM AUTHOR]

The UAV tilt photogrammetry is a method that can be used to obtain large-area and high-precision 3D point cloud data after remote sensing and 3D laser scanning, which has the advantages of low labor intensity, high efficiency and little impact on the environment. It is widely used in various fields, and is in the trial stage in reservoir measurement. In this research, Guniubei reservoir was taken as the study area. The RTK (real-time dynamic difference technology) was used to obtain the coordinates of ground control points. The aerial photogrammetry were carried out by Dajiang spirit 4 UAV (unmanned aerial vehicle), with 35 photo control points and 42 check points, and then 3D model of reservoir was established. Evaluated by mean square error, MS and MH of root control points were 0.051m and 0.065m respectively, and the MH of the detail points was 0.098m, which all met the accuracy requirements. For the tidal-flat area, the safety of UAV photogrammetry was much higher than that of manual field measurement. The outcomes of this research provide basis for comprehensive efficient topographic survey and reservoir capacity of hydraulic engineering. [ABSTRACT FROM AUTHOR]

In order to investigate the pollution characteristics, potential ecological risks and health risks of heavy metals in the soil of the north vegetable base in Suzhou, Anhui, surface soil samples were collected from three vegetable growing areas in the urban (Northern) area, the contents of seven heavy metal elements (Cu, Zn, Co, Ni, Cr, Mn and Pb) in the samples were analyzed, the accumulation and potential risk of heavy metals in soil were evaluated by using soil heavy metal pollution index, potential ecological risk assessment and health risk assessment. The results show that there are middle and light Zn enrichment and heavy Pb enrichment in this area according to the evaluation method of Pollution Index. According to the result of potential ecological risk assessment, the light ecological risk is the main risk in the study area. According to the health risk assessment, there is a non-carcinogenic risk from skin inhalation and a carcinogenic risk from hand, mouth and skin contact in adults and children, areas A and C of the site are major areas for reducing pollution and protecting human health risks. [ABSTRACT FROM AUTHOR]