Mining-affected Areas Research Articles

WITHDRAWN: Characterization of soil response in mining with grouting into overburden bed-separation based on similar material simulation

Revealing the response laws of soils under various mining conditions is of significance for the scientific protection of farmland in mining areas. To avoid the interference from the spatial heterogeneity of natural soil on the research results, similar simulation experiments were employed. Two models for soil responses under mining with and without grouting into overburden bed-separation were designed, and monitoring was conducted for soil quality factors (moisture content, silt and clay content, and bulk density) and surface deformation factors (subsidence, inclined, and horizontal deformation). The results indicate that it can significantly control surface subsidence in mining with grouting into overburden bed-separation, the maximum subsidence value was reduced by 66.67%, the average subsidence value of each measuring point in the main section was reduced by 78.92%, and the subsidence area was reduced by 34.68%. The coefficient of variation of soil quality factors in the mining-affected area was obviously higher than that in the control area and the initial value before mining. Compared with mining without grouting, the variation coefficient of soil quality factor under mining with grouting was reduced by 2.71-6.79%. Soil quality factors and surface deformation factors show a significant quadratic function relationship, among which horizontal deformation has the greatest influence on soil quality factors, followed by subsidence and inclination. Therefore, it can effectively control surface subsidence and protect cultivated land when mining with grouting into overburden bed-separation.

Application of sensing techniques for quantifying CO2 flux and dynamics in environments affected by the fundão dam collapse, mariana, Brazil

The District of Mariana in Minas Gerais, Brazil, witnessed one of the largest natural disasters in history. It involved the deposition of thousands of cubic meters of mining waste on soils near tributaries of the Doce River, resulting in degraded areas and a new environmental landscape. Numerous studies have focused on changes in soil microbiota and physical-chemical attributes. However, studies quantifying and analyzing carbon flux (FCO2) dynamics in the field using proximal sensors under varying temperatures, humidity conditions, and vegetation cover are scarce and nearly nonexistent. These studies could aid in monitoring the recovery of degraded areas and in understanding FCO2 dynamics in such environments. The aim of this study was to quantify and assess FCO2 dynamics using combined sensing techniques in diverse mining-affected areas, comparing different stages of recovery and their vegetation impact, and linking the results to pedoenvironmental factors. To achieve this, four areas were carefully selected and evaluated: affected pasture (AP), pasture (P) (non-affected), mix (MIX), and native trees (NT). In each area, readings were taken using an Infrared gas analyzer (IRGA) sensor, and temperature and soil moisture were measured. Additionally, soil samples were collected for chemical, physical, and biological characterization. Normalized Difference Vegetation Index (NDVI) assessments were conducted using satellites to evaluate vegetation cover. Non-parametric tests (Kruskal Wallis and Principal Component Analyses - PCA) were employed to evaluate differences between the areas and to assess the correlation among the environmental variables. The P area had the highest FCO2 and total organic carbon (TOC), differing significantly from the other site areas. Conversely, AP had the lowest FCO2 and was distinct from other sites. The MIX and NT areas had intermediate FCO2 and TOC values, which were statistically similar to each other. PCA identified distinct patterns in FCO2, soil temperature, and moisture. FCO2 was positively correlated with soil temperature and negatively correlated with moisture. There was a relationship between the biological variables microbial quotient (qMic), metabolic quotient (qCO2), COT, and FCO2. qMic reached the highest values in the MIX area, decreasing linearly from NT to P. Conversely, AP had the lowest qMic. qCO2 had the highest value in AP and NT. The proximal IRGA sensor effectively quantified FCO2 and differentiated mining tailing-affected areas. This assessment incorporated soil temperature, moisture sensors, vegetation index, and soil attribute data. The FCO2 levels were higher in P areas and lower in AP areas. Elevated FCO2 levels were correlated with a high soil temperature and low humidity. In AP, qMic was low, and qCO2 was high, indicating lower FCO2 levels. Conversely, P exhibited a higher FCO2. Higher NDVI values were correlated with elevated FCO2 in areas with specific vegetation cover during environmental recovery, while lower NDVI areas had lower FCO2 levels.

Mercury Dynamics and Bioaccumulation Risk Assessment in Three Gold Mining-Impacted Amazon River Basins.

Mercury contamination from gold mining in the Amazon poses significant environmental and health threats to the biome and its local populations. The recent expansion of non-industrial mining areas has severely impacted territories occupied by traditional communities. To address the lack of sampling data in the region and better understand mercury dynamics, this study used the probabilistic model SERAFM to estimate the mercury distribution and bioaccumulation in fish. The analysis covered 8,259 sub-basins across three major Amazonian basins: the Branco, Tapajós and Xingu rivers. The findings revealed increasing downstream mercury levels, with notable accumulations in the main watercourses influenced by methylation processes and mining releases. The projected concentrations showed that an average of 27.47% of the sub-basins might not comply with Brazilian regulations, rising to 52.38% in the Branco and Tapajós river basins separately. The risk assessment of fish consumption based on the projections highlighted high mercury exposure levels among traditional communities, particularly indigenous populations, with an average of 49.79% facing an extremely high risk in the Branco and Tapajós river basins. This study demonstrated SERAFM's capacity to fill information gaps in the Amazon while underscoring the need for enhanced data collection, culturally sensitive interventions and regulatory updates to mitigate mercury contamination in gold mining-affected areas.

Winter Wheat Aboveground-Biomass Estimation and Its Dynamic Variation during Coal Mining—Assessing by Unmanned Aerial Vehicle-Based Remote Sensing

Underground coal mining in coal-grain overlapped areas leads to land subsidence and deformation above the goaf, damaging cultivated land. Understanding the influencing process of coal mining on cultivated land and crops is important for carrying out timely land reclamation and stabilizing crop yield. Research has been carried out by using crop growth parameters to evaluate the damaging degree of cultivated land when the mining subsidence is stable, but few studies focus on the influence of land damage on crop growth when the subsidence is unstable during coal mining. Therefore, this study tracked the three growth stages of winter wheat by using UAV multispectral imagery to explore the dynamic influence of underground mining on winter wheat aboveground biomass (AGB). Firstly, a winter-wheat-AGB estimation model (R2 = 0.89, RMSE = 2.18 t/ha) was developed by using vegetation indexes (VIs), textures, and terrain data extracted from UAV imagery. Secondly, based on the winter-wheat-AGB estimation model, the winter wheat AGB was successfully estimated and mapped at different growth stages. The AGB of winter wheat in the coal mining-affected area was approximately 5.59 t/ha at the reviving stage, 8.2 t/ha at the jointing stage, and 15.6 t/ha at the flowering stage. Finally, combined with the progress of coal mining, the dynamic changing process of crops during underground mining can be inferred by analyzing the spatiotemporal variation in winter wheat AGB. Results showed that, in the dip direction, winter wheat AGB at the flowering stage was the highest at the compression zone, followed by the inner stretch zone, outer stretch zone, and neutral zone. The distance from the waterlogged area and the existence of cracks were found to be the important moderating variables affecting the crop growth status in the mining subsidence area. In the strike direction, there were significant differences in the wheat AGB-affected area as the mining proceeded. Even areas where AGB had previously significantly increased gradually transitioned to significant decreases with the end of mining. The research explores the dynamic changes in winter wheat AGB and land damage status during coal mining. It provides a rapid and non-destructive land-damage-monitoring method to protect cultivated land in mining areas.

Photochemical transformation and immobilization of thallium in the presence of iron and arsenic: Mechanistic insights from the coupled formation of arsenate complexes

Despite the occurrence of thallium (Tl) in the acidic mining-affected areas being highly positively correlated with iron (Fe) and arsenic (As), the effects of the two accompanying elements on Tl redox transformation and immobilization remain largely unknown. Here, we investigated the photochemical redox kinetics and immobilization efficiency of Tl for a wide range of As/Fe and As/Tl ratios under acidic conditions. We provided the first experimental confirmation of the complexation of Tl(III) with As(V) by the spectrophotometric method and revealed the role of Tl(III)-As(V) complexes in decreasing the photoreduction rate of Tl(III) under sunlight. Additionally, the negative impact of colloidal Fe(III)-As(V) and Fe(III)-As(III) complexes formation on decreasing photoactive Fe(III) speciation and thus the apparent quantum yield of •OH was highlighted, which consequently hindered the oxidative conversion of Tl(I) to Tl(III). We rationalize the kinetics results by developing the model which quantitatively describes the photochemistry of Tl. Furthermore, we demonstrated the colloid-facilitated immobilization of Tl(III) through the formation of Tl(III)-As(V) clusters and surface adsorption onto the complexes. This study broadens the mechanistic understanding of redox transformation and immobilization potential of Tl and aids in assessing Tl speciation as well as its coupled transformation with Fe and As species in the sunlit water environment.

Source and risk assessment of heavy metals in mining-affected areas in Jiangxi Province, China, based on Monte Carlo simulation.

In recent years, heavy metal contamination of soils has become a major concern in China due to the potential risks involved. To assess environmental pollution and human health risks in a typical heavy metal polluted site in Jiangxi Province, a thorough evaluation of the distribution, pollution levels, and sources of heavy metals in soils of the Yangmeijiang River watershed was conducted in this study. Positive matrix factorization and Monte Carlo simulation were used to evaluate the ecological and human health risks of heavy metals. The research findings indicate that heavy metal pollution was the most severe at the depth of 20-40cm in soils, with local heavy metal pollution resulting from mining and sewage irrigation. The high-risk area accounted for 91.11% of the total area. However, the pollution level decreased with time due to sampling effects, rainfall, and control measures. Leaf-vegetables and rice were primarily polluted by Cd and Pb. The main four sources of heavy metals in soils were traffic emission, metal smelting, agricultural activities and natural sources, mining extraction, and electroplating industries. Heavy metals with the highest ecological risk and health risk are Cd and As, respectively. The non-carcinogenic and carcinogenic risks of children were 7.0 and 1.7 times higher than those of adults, respectively. Therefore, children are more likely to be influenced by heavy metals compared to adults. The results obtained by the risk assessments may contribute to the identification of specific sources of heavy metals (e.g., traffic emissions, metal smelting, mining excavation, and electroplating industries). Additionally, the environmental impacts and biotoxicity associated with various heavy metals (e.g., Cd and As) can also be reflected. These outcomes may serve as a scientific basis for the pollution monitoring and remediation in the mining-affected areas.

On the Susceptibility of Reinforced Concrete Beam and Rigid-Frame Bridges Subjected to Spatially Varying Mining-Induced Seismic Excitation.

This paper aims to identify the optimal reinforced concrete bridge construction for regions at risk of mining-induced seismic shocks. This study compares the performances of two common bridge types made of the same structural tissue, i.e., a reinforced concrete beam bridge and rigid-frame bridge under real mining-induced tremors using uniform and spatially varying ground motion models. This study investigates the dynamic responses of the bridges depending on wave velocity and assesses their susceptibility to mining-triggered tremors based on the contribution of quasi-static and dynamic effects in the global dynamic responses of the bridges. This study revealed significant changes in dynamic response under spatially varying ground excitation for both bridge types. It was observed that rigid-frame bridges show higher susceptibility to quasi-static effects due to their stiffness, whereas beam bridges are more susceptible to dynamic stresses. This study recommends that in regions with mining tremors, the choice between bridge types should consider the possibility of limiting individual components of stress. A solution may involve the reduction in quasi-static components through structural reinforcement or decreasing dynamic components by using vibration absorbers. It was found that beam bridges are more cost-effective and practical in mining-affected areas, especially when founded on weak grounds.

Energy Accumulation Characteristics and Induced Rockburst Mechanism of Roadway Surrounding Rock under Multiple Mining Disturbances: A Case Study

The source of energy release when rockburst occurs must be determined to understand the mechanisms underlying disaster formation and achieve accurate prevention and control. Although previous research has systematically investigated the energy source underlying rockburst from different perspectives, issues such as an unclear understanding of the energy accumulation state and inaccurate positioning of the energy release source remain to be resolved. In this study, the “1·17” major roof accident in the Danshuigou Mine was used as the background to evaluate and analyze the stress environment and energy accumulation characteristics of roadway surrounding rock under multiple mining disturbances, and the results showed that a super energy package occurs in the surrounding rock of the mining roadway. Subsequently, the evolution process of energy in this region and the mechanism of induced rockburst were elaborated. The results showed that the degree of stress concentration in the surrounding rock of the roadway will increase several times as the number of mining disturbances increases. Under the influence of multiple mining disturbances, the maximum principal stress peak of the surrounding rock of the roadway can reach 5–10 times the maximum principal stress value outside the mining-affected area. A large amount of elastic energy was accumulated in the rock surrounding the roadway, and super-high-density energy packages were formed locally. The maximum energy density value reached 50–185 times the value observed in areas outside the mining-affected zone. Thus, rockburst may be induced when the large amount of energy accumulated in the super energy package is suddenly and violently released; moreover, the degree of energy accumulation in the super energy package is likely closely related to the magnitude of rockburst. These results have important theoretical significance and application value for clarifying the mechanism of rockburst and improving the effectiveness of rockburst prediction and prevention.

Pollution impact on metal and biomarker responses in intestinal cytosol of freshwater fish.

In the present study, essential and nonessential metal content and biomarker responses were investigated in the intestine of fish collected from the areas polluted by mining. Our objective was to determine metal and biomarker levels in tissue responsible for dietary intake, which is rarely studied in water pollution research. The study was conducted in the Bregalnica River, reference location, and in the Zletovska and Kriva Rivers (the Republic of North Macedonia), which are directly influenced by the active mines Zletovo and Toranica, respectively. Biological responses were analyzed in Vardar chub (Squalius vardarensis; Karaman, 1928), using for the first time intestinal cytosol as a potentially toxic cell fraction, since metal sensitivity is mostly associated with cytosol. Cytosolic metal levels were higher in fish under the influence of mining (Tl, Li, Cs, Mo, Sr, Cd, Rb, and Cu in the Zletovska River and Cr, Pb, and Se in the Kriva River compared to the Bregalnica River in both seasons). The same trend was evident for total proteins, biomarkers of general stress, and metallothioneins, biomarkers of metal exposure, indicating cellular disturbances in the intestine, the primary site of dietary metal uptake. The association of cytosolic Cu and Cd at all locations pointed to similar pathways and homeostasis of these metallothionein-binding metals. Comparison with other indicator tissues showed that metal concentrations were higher in the intestine of fish from mining-affected areas than in the liver and gills. In general, these results indicated the importance of dietary metal pathways, and cytosolic metal fraction in assessing pollution impacts in freshwater ecosystems.

EVALUASI TINGKAT KEBERHASILAN REVEGETASI TERHADAP PERTUMBUHAN DAN KESEHATAN TANAMAN PADA LAHAN BEKAS TAMBANG BATUBARA PT. AMANAH ANUGERAH ADI MULIA DI SITE RIAM ADUNGAN KABUPATEN TANAH LAUT

Mining results in infertile soil, acidic pH and lack of nutrients. Reclamation activities are one way to restore the benefits of land to be better and more productive in solving this problem. Assessment of reclamation success has been carried out on 8 (eight) IUPs, one of which is PT. Amanah Anugerah Adi Mulia (PT. A3M) in Tanah Laut Regency, South Kalimantan Province. Status PT. A3M has entered the post-mining stage and has rehabilitated mining-affected areas through reclamation and revegetation on the inpit dump land which is divided into three areas, namely the AR-05 area of 3.26 ha of the 2011 Planting Year, the AR-07 area of 3.61 ha of the 2014 Planting Year and the AR-07 area of 3.27 ha of the 2017 Planting Year. Therefore, the purpose of this study is to analyze the status of revegetation success related to the growth and health of revegetated plants in PT. Amanah Anugerah Adi Mulia and identified the factors causing the non-success of revegetation related to the characteristics of post-mining revegetation land. The results of the revegetation analysis regarding the percentage of plant growth and health: the percentage of growth was 96% (2011), 100% (2014) and 100% (2017), with a success value of > 90% (successful category) and a percentage of plant health of 91.14% (2011), 99.2% (2014) and 89% (2017), with a plant health value of > 89% categorized as healthy (normal height, fresh leaves and not yellow).

Assessment towards mine closure within IPPKH (Permit of Using Forest Area): Study case of a coal mining Licence at Taba Penanjung, Central Bengkulu, Indonesia

Mine closure is an inevitable event within the mining business; however, post-mining land use is always intended for further beneficial use for further development, mostly to reach a landscape that sustain and give further benefit after the mining operation has finished. One of the mining licence schemes is the permit of using forest area (IPPKH). One of the mining companies at Central Bengkulu has experienced phasing out production towards mine closure. The query is how the mining-affected area can be reclaimed and rehabilitated to become a healthy forest ecosystem. This study aimed to assess the closure criteria based on mine closure regulations. Data were collected from stages of operation according to assessment of mine closure, particularly from rehabilitation sites. The results indicate that rehabilitation sites showed significant re-vegetation of mining-affected areas (dumping area and in-pit backfilling area) and progression to become forested areas, as depicted by structural development of re-forested sites. The overall score is within the suitable range of “good post-mine closure” but require examination and supervision if after mining, the areas are expected to have economic value.

Assessment of Cd Pollution in Paddy Soil-Rice System in Silver Mining-Affected Areas: Pollution Status, Transformation and Health Risk Assessment.

Mining activities are one of the main contamination sources of Cd in soil. However, the information about the influence of silver mining on Cd pollution in soil in mining-affected areas is limited. In the present study, sixteen paired soil and rice grain samples were collected from the farmland along the Luxi River nearby a silver mine in Yingtan City, Jiangxi Province, China. The total, bioavailable, and fraction of Cd in soil and Cd content in rice grain were determined by inductively coupled plasma mass spectrometry. The transformation of Cd in the soil–rice system and potential health risk via consumption of these rice grains were also estimated. The results showed that Cd concentration in these paddy soils ranged from 0.21 to 0.48 mg/kg, with the mean Cd concentration (0.36 mg/kg) exceeded the national limitation of China (0.3 mg/kg, GB 15618-2018). Fortunately, all these contaminated paddy soils were just slightly polluted, with the highest single-factor pollution index value of 1.59. The DTPA- and CaCl2-extractable Cd in these paddy soils ranged from 0.16 to 0.22 mg/kg and 0.06 to 0.11 mg/kg, respectively, and the acid-soluble Cd occupied 40.40% to 52.04% of the total Cd, which was the highest among different fractions. The concentration of Cd in rice grain ranged from 0.03 to 0.39 mg/kg, and the mean Cd concentration in rice grain (0.16 mg/kg) was within the national limitation of China (0.2 mg/kg, GB 2762-2017). The bioaccumulation factor of Cd in rice grain ranged from 0.09 to 1.18, and its correlation with various indicators was nonsignificant (p < 0.05). Health risk assessment indicated that the noncarcinogenic risk for local rice consumers was within the acceptable range, but the carcinogenic risk (CR) was ranging from 1.24 × 10−2 to 1.09 × 10−3 and higher than the acceptable range (1.0 × 10−4), indicating that the local rice consumers suffered serious risk for carcinogenic diseases. The results of the present study can provide reference for safety production of rice in silver mining-affected areas.

Phytoremediation of Heavy-Metals-Contaminated Soils: A Short-Term Trial Involving Two Willow Species from Gloucester WillowBank in the UK

Phytoremediation, as a bioremediation process in which plants are used to remove contaminants from an environment, has proved to be a practical and low-cost strategy for recovering mining-affected areas. This study aims to assess the potential for use in phytoremediation of two willow species, Salix viminalis and Salix dasyclados, by testing their potential for cleaning-up a range of soils with differing heavy metal concentrations: Pb (111, 141, 192 and 249 mg /kg), Zn (778.6, 1482, 2734 and 4411 mg/kg) and Cd (3.00, 5.03, 9.14 and 16.07 mg/kg). The extracted metals were preferentially translocated to the leaves with considerably higher concentrations and relative BAFs in the case of S. viminalis. The highest recorded Zn concentration of over 0.5% was found in the leaves of S. viminalis growing in soil 4. However, under the conditions of the experiments, S. dasyclados showed greater potential for use in phytoremediation, especially if coupled with use of biomass for energy production. An assessment of the suitability of willow species in this role, with regard to wider aspects involved, such as use of resultant biomass and/or waste management, revealed good potential. Willows are fast growing, grow vigorously from coppiced stumps and have extensive root systems. Therefore, their use in bioenergy production through pyrolysis or combustion, coupled with flue gas screening, is strongly advised.

Spatial distribution, geochemical behaviors and risk assessment of antimony in rivers around the antimony mine of Xikuangshan, Hunan Province, China.

Pollutants derived from antimony (Sb) mining can easily cause pollution of surrounding water bodies. However, qualitative source analysis of river pollution is mostly conducted, and quantitative source analysis is still lacking. A total of 21 water samples were collected to analyze the pollution status of the heavy metal element Sb, explore the Xikuangshan (XKS) area river heavy metals pollution mechanism, undertake quantitative analysis of the sources of pollution, and carry out irrigation water suitability assessment and potential ecological risk assessment. The results showed that, compared with the mining non-affected area, the maximum excess multiple of Sb in surface water and rivers in Hunan XKS area is 411.31. When the river fluid flows through the mining-affected area, the heavy metal element Sb content increases rapidly, and then decreases due to dilution process. Positive matrix factorization (PMF) source analysis showed that the main source of Sb pollution in the rivers is the impact of mining and smelting (83.60%), followed by the role of waste rock leaching (16.40%). After irrigation, 27.78% of the river water had strong ecological risks, and 16.67% had extremely strong ecological risks. This achievement provides a theoretical basis and technical guarantee for protecting and using the local water body of the mining area.

Phytoplankton communities as bio-indicators of water quality in a mining-affected area of the river Ganga, Haridwar, India

Phytoplankton communities as bio-indicators of water quality in a mining-affected area of the river Ganga, Haridwar, India

The solid-state partitioning, distribution, and mineralogical associations of arsenic and antimony: Integrated findings from the Altiplano Puna, South America and international comparisons

Arsenic (As) and antimony (Sb) are potentially hazardous metalloids and their presence in the environment is often related to mineral deposits, mines, and thermal springs. Despite their similar chemical properties, the distribution and behavior of As and Sb in nature has been shown to differ. In order to contribute to a better understanding of As and Sb in the environment as well as the important parameters controlling their mobility, this study presents a synthesis of geochemical results in the Altiplano-Puna of Chile and Bolivian Sb belt. Analyses include (i) solid-state partitioning, (ii) mineralogical studies and (iii) concentrations of both metalloids in groundwater, surface water, porewater, and fluvial and lake sediments in distinct seasons. Consistencies were found between the mobilization patterns of As and Sb in the studied sites where As is generally more mobile than Sb; however, mining-affected areas in the Bolivian Sb belt tend to be associated with a higher proportion of mobile Sb. From a mineralogical standpoint, As is generally associated with iron oxides and hydroxides and As-bearing pyrites, while Sb is linked to iron oxides, hydroxides, and clay-sized phyllosilicates. When compared to different metallogenic settings outside the Altiplano-Puna plateau (the Loa River Basin of northern Chile and Xikuangshan Mine in China), the following conclusions are consistent with the results obtained from the Altiplano-Puna: dissolved Sb concentrations tend to decrease with distance from the respective mining facility, the mobility of Sb is typically lower than As, and the preferred mineralogical associations are iron oxides and hydroxides. Finally, based on the seasonal analysis of As and Sb, it is conceptualized that wetlands behave as a source of As and as a sink and source of Sb depending on the water column; in addition, consideration must be taken regarding aeolian weathering.

A Vertical Joint Spacing Calculation Method for UDEC Modeling of Large-Scale Strata and Its Influence on Mining-Induced Surface Subsidence

While universal discrete element code (UDEC) is widely used for understanding the mechanism of large-scale strata movement and the effects of mining subsidence on the environment, the fundamental knowledge of how to set vertical joint spacing (VJS) in UDEC is still not fully understood. To address the knowledge gap, we first present a novel VJS calculation method, then conduct UDEC experiments, and finally compare the predictions of UDEC models with field subsidence observation. The results suggest the following: (1) when compared to the conventional VJS setting (1× to 3× bed thickness), the maximum surface subsidence (MSS) prediction via UDEC models based on our proposed VJS setting method is closer to field observation; (2) a smaller but varying VJS setting can also have the effect of a larger VJS setting; and (3) with the increase in VJS, MSS first drops, then rises, and reaches the minimum when VJS is set at approximately 7× bed thickness. This paper provides an explanation of the VJS setting in UDEC and establishes a bridge between the KS theory and VJS, which is helpful for the sustainable development of such an UDEC modeling strategy and for a better understanding of the influences of mining subsidence on the environment in mining-affected areas.

Monitoring and Early Warning of Transmission Line External Breakage Based on Satellite-Ground Coordination

This article first proposes a high-precision spatio-temporal registration method between satellite remote sensing images and ground sensors. Then, using satellite remote sensing images, an intelligent identification model for typical external damage hidden dangers of transmission lines based on satellite remote sensing is established to realize intelligent identification of transmission line construction work areas and mining affected areas. Aiming at the results of intelligent identification of construction work areas and mining-affected areas, the proposed YOLOv4-based external damage identification algorithm for transmission lines is used to detect external damage hidden dangers. Through the method in this paper, it is possible to realize a regular general survey of hidden dangers of external damage (construction work area, mining affected area) with full coverage of transmission channels, and carry out targeted 24-hour monitoring on the ground. The test results show that the satellite-ground coordinated transmission line external damage monitoring and early warning in this paper. The method timely and accurately realizes the monitoring and early warning of the external breakage of the transmission line.

Risk assessment of cadmium intake via food among residents in the mining-affected areas of Nandan County, China

This study investigated the dietary structure, Cadmium (Cd) contents in foods and exposure to Cd through diets of the residents in the mining-affected areas of Nandan County in summer 2013 (July to August) and winter 2014 (November to December). The weighing of foods and the chemical analysis of foods were applied to determine the dietary structure, and the concentration of trace element Cd in the diets, respectively, of the residents in the mining-affected areas (Chehe town, Dachang town, and Zhanglao town) and a control area (Liuzhai town), and subsequently the Cd exposure from the diets was estimated. In the mining-affected areas, the geometric mean of Cd in rice and rice products was the highest (0.29μg/g) among all food types, and it exceeds the value of 0.2ug/g from the China Food Safety National Standard for Maximum Levels of Contaminants in Foods (GB2762-2017). The Cd contents in rice and rice products, vegetables, and beans in the mining-affected areas were significantly higher than those in the control area. The estimated daily food intakes of Cd in the mining-affected areas were higher than the intake in the control area. The THQ in the mining-affected areas of Chehe town, Dachang town, and Zhanglao town was 3.03, 2.31, and 3.27, respectively. All of which were higher than the value of 1.44 in the control area. Thus, the high level of dietary cadmium intakes of residents in this area deserves our attention.

Research on InSAR Monitoring Precision Analysis of Coal Mining Influence Based on Long Time Sequence

In this paper, in view of the scope of coal mining subsidence, the magnitude of subsidence deformation and the impact on buildings (structures), InSAR technology is selected for monitoring, time series analysis method combined with D-InSAR method for processing, and Sentinel- 1 Satellite IW data and RADARSAT-2 satellite XF data have been monitored for four years in the mining-affected area and its surrounding areas. The results show that there are obvious subsidence ranges on the surface of the current mining area and the unstable settlement area. The Shen District has been in a stable state in recent years, and the time sequence analysis for more than 3 years has verified the high accuracy and reliability of the monitoring results. The analysis of the monitoring results shows that the InSAR technology can be used for mining subsidence monitoring, especially when determining the subsidence boundary and whether it is stable or not, it has its technical superiority.