Environment In Mining Area Research Articles

Assessment of Blast-Induced Ground Vibration Frequency in Opencast Coal Mine: a Multivariate Statistical Regression Model

The blasting is a useful technique to explore and extract the mineral resources. It gives desired output with several negative impacts in surrounding mining areas. The ground vibration is one of the most concern phenomena produced by blasting. The peak particle velocity and frequency assess the seismic hazard, risk, and the human discomfort. Frequency plays a key role to define the damage criteria limits and human discomfort. The frequency of blast-induced ground vibration depends mainly on amount of explosive, characteristic properties of rock mass and distance etc. A total number of 32 datasets have been recorded in the form of velocity components and corresponding frequencies such as; Radial, Vertical, and Transverse at an opencast mine ‘A’ located in Chhattisgarh. The Indian Standard developed the safe level of peak particle velocity at frequency range (<8Hz, 8Hz - 25Hz, >25Hz) for the various types of structures close to mine. An attempt has been made to establish the relationship among parameters such as; burden, spacing, stemming, charge, hole depth, hole diameters and distance, etc. by multivariate statistical regression analysis (MVSRA) for the prediction of ground vibration frequency. The Coefficient of Determinate (CoD) between measured and predicted frequencies has also been studied.

Does the trans-regional transfer of resource-oriented enterprises generate a stress effect?

Whether the trans-regional transfer of resource-oriented enterprises produces a stress effect is a major issue concerning the green, sustainable, and high-quality development of resource-rich areas in the mid-west of China. Using the system engineering concept and socioeconomic statistics, in combination with a theoretical analysis and empirical testing, this study analyzed the functional characteristics of the natural environment in the region and clarified the mechanism characteristics by which a natural environment functional stress effect could be caused by the trans-regional transfer of resource-oriented enterprises. Resource-orientated industry data from 2000 to 2015 in the three mid-western provinces of Shanxi, Shaanxi, and Guizhou were selected for empirical testing. Several key findings were made. (1) The trans-regional transfer of resource-oriented enterprises had a significant strengthening effect on the five stress indicators of land subsidence, solid waste, waste water, waste gas, and dust in the three provinces of mid-west China. (2) The trans-regional transfer of resource-oriented enterprises led to the restoration of the natural environment in mining areas, which was coordinated by relevant governments and enterprises, resulting in a significant weakening of the land subsidence, solid waste, and waste water stress in the three provinces of the mid-west, as well as a significant weakening of the waste gas stress in Shaanxi Province and dust stress in Guizhou Province. (3) The trans-regional transfer of resource-oriented enterprises had a higher positive intensification effect than a negative weakening effect on the natural environment functional stress in the three provinces of the mid-west. (4) In a comparison of the effects of natural environment function stress due to the trans-regional transfer of resource-oriented enterprises there were large differences among the three provinces in terms of the intensifying and weakening flows of stress. The conclusions provide a theoretical basis for the formulation of relevant policies to regulate the trans-regional transfer of resource-oriented enterprises and reduce the stress effect.

Competitive Inhibitory Effect of Calcium Polypeptides on Cd Enrichment of Brassia campestris L.

Most cadmium-polluted farmland and land surrounding mining areas are difficult to repair and control, seriously threatening the food safety of the crops planted in these regions. As an essential element for plant growth, calcium plays an important role in stress-resistance regulation. In this study, Brassia campestris L. was used as the experimental material and polluted soil with cadmium was used as the experimental soil sample, to explore the competition inhibition of calcium polypeptide application on the absorption of Cd2+ by Brassia campestris L. in the growth process, as well as the effect of calcium application on the growth. Results showed that the application of calcium polypeptides significantly promoted the growth of Brassia campestris L. Calcium polypeptides could be used as high-quality fertilizer, alleviating the effect of Cd2+ stress on the growth of Brassia campestris L., and promoting the absorption of K+, Ca2+, and other nutrients by Brassia campestris L. Under different calcium polypeptide application conditions, the effective state of Cd2+ in the soil showed less significant difference, indicating that the calcium polypeptide had weak or limited passivation effects on Cd2+. There was a significantly negative correlation between Cd concentration in Brassia campestris L. and calcium application (r = −0.99, p < 0.01) when calcium polypeptide was over-applied, which indicates that the inhibition effect of Cd2+ absorption on Brassia campestris L. is mainly through competitive inhibition rather than passivation. The results showed that calcium polypeptide has dual functions on the competitive inhibition of heavy metals and a good fertilizer effect, providing a new technology for in situ remediation of heavy-metal pollution, and a new approach for the treatment of cadmium-contaminated farmland and surrounding mining land.

Impacts of Large-Scale Open-Pit Coal Base on the Landscape Ecological Health of Semi-Arid Grasslands

Coal is an important energy resource in the world, especially in China. Extensive coal exploitation seriously damaged the grassland and its fragile ecosystem. However, temporal and spatial impact laws of open-pit coal exploitation on Landscape Ecological Health (LEH) of semi-arid grasslands are still not clear. Therefore, the main objective of this paper is to study impact of Large-scale Open-pit Coal Base (LOCB) on the LEH of semi-arid grasslands from the perspectives of temporal and spatial. Taking Shengli LOCB of Xilinguole grassland in Inner Mongolia as an example, we demonstrate a conceptual model of LOCB impact on LEH of semi-arid grasslands, and establish a research system called landscape Index-pattern Evolution-Driving force-Spatial statistics (IEDS). A complete process integrated from investigation, monitoring, and evaluation to the analysis of impact laws was developed. Result indicated that coal mining causes gradual increase of landscape patches, landscape fragmentation, gradual decline of landscape connectivity, complexity and irregularity of landscape shape, enhancement of landscape heterogeneity and complexity, gradual decline of landscape stability, gradual decrease of grassland landscape and annual increase of unhealthy grassland landscape. The LEH of grassland basically belongs to the state of slight deterioration. In the past 15 years, the spatial and temporal distribution characteristics of LEH in the study area are similar. This study provides scientific reference for ecological disturbance research, environmental protection, landscape planning, restoration and renovation of ecological environment in mining areas. At the same time, future research should integrate geological, hydrological, soil, vegetation, microorganisms, animals, climate, and other perspectives to study the impact of mining on landscape ecology deeply.

DAMPAK POSITIF AKTIVITAS PERTAMBANGAN NIKEL TERHADAP KONDISI SOSIAL EKONOMI MASYARAKAT DI KECAMATAN TINANGGEA KABUPATEN KONAWE SELATAN

One sector that contributes to foreign exchange is the dominant mining sector. This mining sector contributes 36% of the country's revenue. Among the activities of the nickel mining industry, it has had a positive impact on the state treasury from taxes and royalties. Therefore, the existence of these natural resources has economic potential that must be utilized in order to prosper the lives of the people in accordance with the provisions of Article 33 of the 1945 Constitution (paragraph 2). This study tries to examine the positive impact of nickel mining activities on the socio-economic conditions of the community. The purpose of the study was to describe the positive impact of nickel mining activities on the socio-economic life of the community in Tinanggea sub-district. The research method uses a qualitative approach based on data collection with observation techniques, interviews with informants and review documents related to this research.the results showed that the positive impact of nickel mining activities in Tinanggea District was that it could accommodate local workers or increase the opportunity for people to get jobs in mining companies, increasing community income through monthly salary gains, increasing micro-businesses in the surrounding mining areas. buying and selling activities between the community and employees working in mining companies. While the conclusions of the study were that mining activities in Tinanggea Subdistrict had a positive impact on the people of the region. Keywords : Positive impact of nickel mining activities, Socio-economic community.

Metal(loid) uptake of Sonchus oleraceus grown around Cheshmeh-Konan copper deposit, NW Iran

Heavy metal(loid) contamination in the environment of mining areas has become an important problem. Cheshemeh-Konan is one of the main copper deposits in NW Iran that is currently abandoned. In the present work, the intensity of some metal(loid) pollutions in the soil of the mining area was assessed using three reliable indices. In addition, the potential of Sonchus oleraceus L., as the dominant plant grown in the area, in the uptake of some metal(loid)s from the soil was evaluated. The plant and soil samples were collected from the mining area and analyzed by inductively coupled plasma-mass spectrometry (ICP-MS). The results obtained revealed that the soil of the studied mining area was considerably contaminated by As (CF = 3.1), Cr (CF = 3.8), and Ni (CF = 4.07). It was confirmed that S. oleraceus had a good ability to accumulate Cd (0.74 mg/kg), Mo (0.67 mg/kg), Sr (285.80 mg/kg), Sn (161.10 mg/kg), and Sc (30.35 mg/kg) when mean concentrations of these metals in the soil were 0.14, 0.12, 161.05, 1.94, and 17.9 mg/kg, respectively. The plant biological absorption coefficient for these 5 elements was more than 1. The correlations between the Mo and Sr contents in the soil and plant were significantly positive. According to the results obtained, the present work provides some geochemical findings about the substrate, and leads to the increasing information about the relationship between the element concentrations in the plants and different soils.

Ground Subsidence and Surface Cracks Evolution from Shallow-Buried Close-Distance Multi-seam Mining: A Case Study in Bulianta Coal Mine

To explore the law of ground deformation from shallow-buried close-distance multi-seam mining, an observation station was built in the Bulianta Coal Mine to measure and record the periodic variation of related parameters about ground subsidence and surface cracks with the advancement of working face. From the data observed from the field, it can be found that, when lower seam mining, the ground subsidence above the previously mined area was deeper and steeper than that above the left pillar; besides, the influence scope of the former was larger than that of the latter. In terms of ground cracks, the ground cracks were formed ahead of the working face and developed rapidly during the period of the breakage of the immediate roof. Besides, the average interval of the ground cracks above the previous gob was 14.75 m, and still existed and hardly changed after the advancement of the working face; while that above the left pillar was 27.8 m and most of them were closed. In addition, when the advance rate of the working face was 12.8 m/day, the advance influence distance of the mining surface crack reached the minimum of 13.6 m. This finding is helpful for protecting the surficial environment in mining area during and after mining operations and is also of significance to conduct green mining in other mining areas.

Effects of heavy metal pollution on soil physicochemical properties and microbial diversity over different reclamation years in a copper tailings dam

The proliferation of copper (Cu) mines has led to a rapid rise of tailings dams comprised of mining metal mineral material, causing serious damage to the ecological environment of mining areas. Soil physicochemical characteristics, enzyme activities, and microbial diversity are important indices for ecosystem functions as well as being important factors in evaluating soil restoration characteristics. This study selected nine Cu tailings subdams in Yuanqu County, Yuncheng City, Shanxi, China, to analyze the effects of heavy metal pollution on soil physicochemical properties and microbial diversity over different years of reclamation. We found that these different years of reclamation exhibited significant differences in physicochemical properties, and as restoration progressed, soil nutrient concentrations (i.e., carbon [C] and nitrogen [N]) significantly increased. Furthermore, we found significant negative correlations between catalase and the soil C and N ratio (C/N). In addition, urease was significantly positively correlated to N, C, and cadmium (Cd) as well as bacterial gene copies but was negatively correlated to zinc (Zn). Sucrase, on the other hand, was negatively correlated to Cd and bacterial gene copies. Over subsequent years of reclamation, we found that environmental factors affected bacteria more than fungi. Soil fungi diversity gradually increased as restoration progressed over consecutive years, while soil bacteria correspondingly exhibited an irregular trend. Results from this study could provide an ecological basis for further studies on soil ecosystem restoration and degradation mechanisms associated with Cu tailings dams.

Linguistic neutrosophic Hamacher aggregation operators and the application in evaluating land reclamation schemes for mines.

Land reclamation has become a significant way for the improvement of ecological environment in mining areas. When selecting the optimal land reclamation scheme, LNNs (linguistic neutrosophic numbers) are suitable to describe the complex fuzzy evaluation information through linguistic truth, indeterminacy and falsity membership degrees. Furthermore, the Hamacher aggregation operators are good tools to handle multi-criteria decision making problems. Accordingly, the aim of this paper is to extend Hamacher aggregation operators with LNNs and then build a decision making framework for evaluating land reclamation schemes in mining areas. First, new operational laws of LNNs based on Hamacher t-norm and t-conorm are defined. Then, several linguistic neutrosophic Hamacher aggregation operators, including the linguistic neutrosophic Hamacher weighted mean aggregation operators and linguistic neutrosophic Hamacher hybrid weighted mean aggregation operators are developed. Meanwhile, their desirable properties are proved. Thereafter, a method for decision making with linguistic neutrosophic information based on these operators is proposed to deal with complex decision problems. At last, the validity of this method is confirmed by an illustrative example of evaluating the land reclamation schemes in mining areas. In addition, the impact of the parameter in extended Hamacher aggregation operators is discussed. The merits of the proposed method are also highlighted by comparing with other decision making methods. The results show that the proposed linguistic neutrosophic Hamacher aggregation operators have great flexibility and advantages, and can provide powerful ways for the evaluation of land reclamation schemes.

Various Phyllosphere and Soil Bacterial Communities of Natural Grasses and the Impact Factors in a Copper Tailings Dam.

Copper mining caused severe damage to the ecological environment of mining areas. The combination of microbe and plant remediation has an application potential in improving the absorption and transformation efficiency of heavy metals. The phyllosphere is the largest biointerface on the planet, and bacteria are the dominant microbial inhabitants of the phyllosphere, believed to be critical to plant growth and health. This study investigated the phyllospheric and soil bacteria communities using high-throughput sequencing, and endophyte infection statuses of four natural grasses by toluidine blue heparin assay. Results showed variation in phyllospheric bacterial community structure. Gammaproteobacteria were the most abundant bacterial population. Bacilli were found in the phyllosphere of Bothriochloa ischaemum and Imperata cylindrica, while Clostridia were only found in Calamagrostis epigejos. Alphaproteobacteria were the dominant bacteria in soil. In addition, bacterial communities were influenced by endophytic infection statuses. Oxalobacteraceae was associated with soil carbon and sulfur. Enterobacteriaceae had negative correlation with the ratio of soil carbon and nitrogen, and had positive correlation with Cd content. These results offer useful insights into phyllospheric bacterial community variance in four different natural grasses in a copper tailings dam.

Effects of Heavy Metals on Phyllosphere and Rhizosphere Microbial Community of Bothriochloa ischaemum

Copper mining has resulted in severe damage to the ecological environment of mining areas. This study investigated heavy metal distribution in plants and compared the driving factors between aboveground and subsurface microorganisms, as well as the diversity in rhizosphere and non-rhizosphere soil microbial community response to heavy metal transfer factors in a copper tailings dam. We analyzed phyllosphere and soil microbial community using high-throughput sequencing and denaturing gradient gel electrophoresis, respectively. Although we detected chromium in aboveground and subsurface of Bothriochloa ischaemum specimens, no chromium was detected in soil. Total nitrogen was negatively correlated to the carbon and nitrogen ratios of plants and soil, respectively, while the total sulfur was negatively correlated to cadmium in roots. On the contrary, soil sulfur was positively correlated to cadmium in soil. Moreover, soil sulphur was the main influencing factor on the soil bacterial community, while ammonium nitrogen, total nitrogen, and zinc were the driving factors of fungi diversity in non-rhizosphere soil. Fungi diversity in the rhizosphere was significantly correlated to phosphatase, and fungi diversity in the non-rhizosphere was significantly correlated to sucrose enzymes. The transfer factor of lead was negatively correlated to rhizosphere fungi diversity, and the transfer factor of copper was significantly correlated to non-rhizosphere bacterial diversity. Results from this study may offer some scientific reference for the improvement of plant-microbe remediation efficiency. At the same time, this study could provide an ecological basis for further studies on soil ecosystem restoration and degradation mechanisms that are associated with copper tailings dams.

Diversity of microbial communities potentially involved in mercury methylation in rice paddies surrounding typical mercury mining areas in China.

Mercury can be a serious hazard to human health, especially in paddy soils surrounding mining areas. In this study, mercury (Hg)‐methylating microbes with the potential biomarker gene hgcA were obtained from 45 paddy soil samples in mercury mining areas in Fenghuang, Wanshan, and Xunyang. In different areas, the abundance of the hgcA gene was affected by different environmental factors, including organic matter, pH, total carbon content, total nitrogen content, and total mercury content. Phylogenetic analysis showed that hgcA microbes in paddy soils were potentially members of the phyla Proteobacteria, Euryarchaeota, Chloroflexi, and two unnamed groups. Canonical correspondence analysis showed that pH and organic matter impacted the hgcA gene diversity and the microbial community structures in paddy soils. The identification of Hg‐methylating microbes may be crucial for understanding mercury methylation/demethylation processes, which would be helpful in assessing the risk of methylmercury contamination in the food chain.

Distribution of heavy metals and arsenic in soils and indigenous plants near an iron ore mine in northwest Iran

Heavy metal contaminations in the environment of mining area have become a global problem. The vicinity of an iron ore mine was investigated to estimate the concentrations of As, Pb, Cd, Mn, Ni, Zn, and Cr in the soil and the feasibility of using native plants for phytoremediation. For this, concentrations of elements in soil samples collected and were analyzed by inductivity coupled plasma optical emission spectrometry. The concentrations of heavy metals and arsenic in the roots and aerial parts of Dactylis glomerata L. and Scleranthus orientalis Rössler were analyzed by inductively coupled plasma mass spectrometer too. As concentrations in the samples surpassed the soil toxicity threshold. Cd concentration in soil samples was considerably high next to mine pit. Neither species was identified as a hyperaccumulator, but both species could be considered as excluder plants for As.

Modeling the Effects of Phosphate Mining on Groundwater at Different Stages of Mine Development

In this study, a three-dimensional hydrogeological conceptual model was developed and a numerical model was calibrated with Visual MODFLOW to predict groundwater flow and evolution of groundwater field at different developmental stages at a large phosphate mine in Leibo, China, the Baku mine. ArcGIS was used to quantify changes in groundwater flow direction. The development of the cone of depression in the surrounding mining areas was predicted and the associated environmental impacts were discussed. At the beginning of mining, the cone of depression is limited to near each mining subarea and the drawdown is relatively small. The cone spreads out to the Liutong River as excavation proceeds. The model also estimated groundwater inflow rates into the different mining tunnels. The greatest inflow rate occurred in mining subarea M1.2 due to its large scale of mining and low elevation of the bottom of the tunnel. The results of this study can be used to plan optimal groundwater pumping and mine dewatering for safe mining at different mine development stages.

Subsidence Mechanism and Stability Assessment Methods for Partial Extraction Mines for Sustainable Development of Mining Cities—A Review

Partial extraction methods such as underground strip pillar mining or room-and-pillar mining are widely adopted techniques to control ground subsidence. However, pillar failure in partial extraction mines may introduce violent secondary ground collapses. The stability of partial extraction mines dictates the safety of ground surface structures and the environmental health state of the surrounding mining areas. To reuse mining subsidence lands, it is necessary to evaluate the stability of the land through mine subsidence assessments. This paper summarizes current pillar stability assessment methods and their limitations, and the rock mechanics associated with the stability of abandoned mines. The effects of multiple factors that affect mine stability are discussed in detail; special attention has been extended to discuss the weathering effects associated with infused water and spontaneous combustion, as these are some key reasons for pillar strength degradation in abandoned mines. The mechanism of mine collapse and the corresponding post-mining disasters are also summarized. Finally, suggestions and strategies to improve current mine stability assessment methods are proposed based on the perspective of subsidence control.

Mercury distribution in the environment of mining areas in the Altai Republic (Russia)

Mercury distribution in the environment of mining areas in the Altai Republic (Russia)

Configuring the living environment in mining areas in Angola: Contestations between mining companies, workers, local communities and the state

The creation of residential areas near diamond mining operations in Angola has been since its inception in the 1900s both the main driver of settlement and the condition for economic inclusion. Today, private corporations and the state manage mining towns associated to large-scale ventures. The local population rarely has access to employment in these mines or to the residential facilities of mine villages. At the same time, the increased control of artisanal mining leaves most local communities with fewer economic options and infrastructural improvements out of the cities do not reach all. Claims for better livelihoods and infrastructure in towns linked to large-scale mines have increased over the years and constitute an unprecedented strategy to access mining wealth. Resettlement areas, where state and companies are building new towns agglomerating the scattered surrounding villages as part of social responsibility programs become places of contestation among local communities, companies, and the state. This paper addresses the negotiations surrounding such programs, focusing on the expectations of the local community amid the conditions set by the urbanization policies of mining companies and the state, ultimately showing how these are new interplays within the Angolan mining contexts.

Comprehensive evaluation of ecological security in mining area based on PSR–ANP–GRAY

ABSTRACTWith the large exploitation of mineral resources, a series of problems have appeared in the ecological environment of the mining area. Therefore, evaluating the ecological security of mining area is of great significance to promote its healthy development. In this paper, the evaluation index system of ecological security in mining area was constructed from three dimensions of nature, society and economy, combined with Pressure–State–Response framework model. Then network analytic hierarchy process and GRAY relational analysis method were used to evaluate the ecological security of the region, and the weighted correlation degree of ecological security was calculated through the index data of a coal mine from 2012 to 2016 in China. The results show that the ecological security in the coal mine area is on the rise as a whole, though it alternatively rose and dropped from 2012 to 2016. Among them, the ecological security of the study mining area is at the general security level from 2012 to 2015, and at a relatively safe level in 2016. It shows that the ecological environment of the study mining area can basically meet the requirement of the survival and development of the enterprises.

Analysis on Influence Factors of Mining Subsidence in Backfilling under Thick Loose Layer

Mining subsidence, mine solid waste emissions caused by the direct cause of ecological environment deterioration in mining area, effective control and reduce the surface subsidence and reasonable control and utilization of mine wastes, and realize green mining is a fundamental way to reduce the damage of the ecological environment in mining area. To solve this problem, using FLAC3D dimensional numerical simulation method, the above four factors were changed to simulate the surface movement and deformation, and the influence of the above four factors on the maximum surface subsidence was discussed. By using the orthogonal experiment, the importance of the four factors is queued, and the correlation degree ranking of the maximum subsidence value is obtained. The influence degree of the factors on the maximum surface subsidence is: the filling ratio, the thickness of the key stratum, the strength of the filling body and the thickness of the loose layer. In this paper, the content of the three under pressure coal mining area of production practice to provide basic data, can improve the recovery rate of coal resources, reduce the cost of filling, the maximum economic benefits. Has important practical significance to protect the ground structure, reduce the ecological damage, and realize the sustainable development of coal mine.

Effects of natural factors on the spatial distribution of heavy metals in soils surrounding mining regions

Various studies have shown that soils surrounding mining areas are seriously polluted with heavy metals. Determining the effects of natural factors on spatial distribution of heavy metals is important for determining the distribution characteristics of heavy metals in soils. In this study, an 8km buffer zone surrounding a typical non-ferrous metal mine in Suxian District of Hunan Province, China, was selected as the study area, and statistical, spatial autocorrelation and spatial interpolation analyses were used to obtain descriptive statistics and spatial autocorrelation characteristics of As, Pb, Cu, and Zn in soil. Additionally, the distributions of soil heavy metals under the influences of natural factors, including terrain (elevation and slope), wind direction and distance from a river, were determined. Layout of sampling sites, spatial changes of heavy metal contents at high elevations and concentration differences between upwind and downwind directions were then evaluated. The following results were obtained: (1) At low elevations, heavy metal concentrations decreased slightly, then increased considerably with increasing elevation. At high elevations, heavy metal concentrations first decreased, then increased, then decreased with increasing elevation. As the slope increased, heavy metal contents increased then decreased. (2) Heavy metal contents changed consistently in the upwind and downwind directions. Heavy metal contents were highest in 1km buffer zone and decreased with increasing distance from the mining area. The largest decrease in heavy metal concentrations was in 2km buffer zone. Perennial wind promotes the transport of heavy metals in downwind direction. (3) The spatial extent of the influence of the river on Pb, Zn and Cu in the soil was 800m. (4) The influence of the terrain on the heavy metal concentrations was greater than that of the wind. These results provide a scientific basis for preventing and mitigating heavy metal soil pollution in areas surrounding mines.