Daliuta Mining Research Articles

Influence of mining on vegetation in semi-arid areas of western China based on the coupling of above ground and below ground – A case study of Daliuta coalfield

Underground mining operations are known to result in extensive surface subsidence, introducing a multitude of disturbances to surface vegetation, with particularly severe environmental impacts in the fragile ecosystems of arid and semi-arid regions. This study focuses on the Daliuta mining area located in semi-arid zones, selecting four distinct areas for data analysis. Areas A, B, and C fall within the mining perimeter and have all been affected by mining-related disturbances. Following coal extraction, Areas A and B underwent artificial rehabilitation measures, including fracture infilling and sea buckthorn plantation; Area C was left in its natural state without any artificial interference. Area D, unaffected by mining activities, was designated as the control group. The research utilized 60 Landsat satellite images spanning from 1988 to 2022. Employing the Normalized Difference Vegetation Index (NDVI) and the Fractional Vegetation Cover (FVC), the study classified the experimental zone’s vegetation cover and degradation into six levels, ranging from low to high. By comparing the average vegetation cover over an extended period, changes across different vegetation cover levels, and the degree of vegetation degradation before and after mining, the study assessed the impact of underground mining on surface vegetation. The conclusions drawn are as follows: Mining operations caused significant damage to the vegetation in Areas A and B, yet artificial restoration measures notably improved the vegetation quality, with an overcompensation effect observed in Area A, suggesting the potential for ecological restoration efforts to create a vegetative environment that exceeds its original condition in the long term. Mining activities also induced continuous ecological adverse effects in Area C, but the natural regeneration process progressively restored the vegetation to pre-mining levels over time. Based on these findings, the study reveals the spatiotemporal patterns of vegetation damage and recovery across different mining periods and land reclamation stages. It proposes a restoration strategy for mine areas in semi-arid regions that prioritizes natural regeneration supported by artificial guidance. This work provides valuable insights and guidance for assessing the impact of underground coal mining on surface vegetation in semi-arid areas, as well as for the rehabilitation and ecological reconstruction of mine areas, emphasizing the necessity and urgency of conducting environmental assessments and implementing restoration measures.

Study on the strength deterioration characteristic and damage model of coal pillar dams with repeated water immersion in underground reservoirs

The continuous operation of coal mine underground reservoirs exposes the coal pillar dams to mining disturbances and prolonged water immersion, resulting in the deterioration of coal pillars' mechanical properties and posing a serious threat to the dam stability. To this end, coal samples from the proposed pillar dam in the 5–2 coal seam of Daliuta Mine in Shendong Mining Area were selected for conducting water absorption tests and triaxial compression tests under conditions of repeated water immersion, in order to study the deterioration of the mechanical properties and acoustic emission damage characteristic of coal samples as well as the mechanism behind the deterioration of coal samples under the water–rock interaction. The results indicated that: (1) the saturated water content of coal samples exhibited a progressive increase as the water immersion times increased, but with a diminishing rate of growth. (2) As the water immersion times increased, the compressive strength, cohesive force, and internal friction angle of coal samples gradually decreased. Notably, the deterioration effect was more pronounced in compressive strength and cohesive force, while the decline in internal friction angle was relatively minor, and the total deterioration degree and the stage deterioration degree of the above three had evident cumulativity and non-uniformity. The progressive rise in water immersion times led to a gradual attenuation of the deterioration effect. Meanwhile, the confining pressure exhibited a certain inhibitory impact on the strength deterioration of coal samples. (3) Compared to the dry coal samples, the average AE count rate of coal samples subjected to a single water immersion exhibited a significant decrease, and subsequent water immersion for two, three, and four times resulted in a very minor decrease in the average AE count rate. (4) The AE cumulative ringing counts in coal samples exhibited varying degrees of reduction as water immersion times increased. Specifically, the most significant decrease in AE cumulative ringing counts occurred after the initial water immersion, followed by a gradual decrease thereafter. The energy-releasing capacity of coal samples decreased, while their plasticity exhibited a gradual increase. (5) A damage model was developed for coal samples based on the water immersion times. The model indicated that the damage to coal samples increased as the water immersion times increased, and the damage rate gradually decreased and eventually stabilized. (6) The deterioration mechanism of coals under the water–rock interaction was explained. Through repeated water immersion, the physical, chemical, and mechanical interactions between water and coal induced alterations in the internal microstructure of coal samples, resulting in the deterioration of mechanical properties such as compressive strength, cohesive force, and internal friction angle, which was a cumulative damage process from the microscopic to the macroscopic level.

Pore structure evolution of tar-rich coal with temperature-pressure controlled simulation experiments

Tar-rich coal, with a tar yield of 7–12%, has significant potential for hydrocarbon resources. In this study, typical tar-rich coal samples from Daliuta mining area were selected as the research object to conduct temperature–pressure controlled simulation experiments that simulated stratigraphic conditions. The pore characteristics of the tar-rich coal during coal metamorphism were studied, and the pore evolution law of the tar-rich coal was revealed. The findings demonstrate that this experiment successfully simulates all coal ranks, from low coal rank to high coal rank. Tar-rich coals contain pores of five different genetic types. Gas pores and fissures exhibit a tendency toward growth, while cellular pores are gradually broken and collapsed by compaction, showing a tendency to reduce pores. Mold pores and intergranular pores remain basically unchanged. According to the quantitative analysis of pore structure, each pore has a different evolutionary pattern. Macropores are the primary source of pore volume, micropores are the most active pore component in evolution, and mesopores exhibit a diminishing and then growing “U” shape characteristic. Three phases of tar-rich coal pore evolution—Ro, max < 0.9%, Ro, max = 0.9–3%, and Ro, max > 3%—can be distinguished, and there is a strong correlation between these stages and the coalification jumps.

Reasonable Size Design and Influencing Factors Analysis of the Coal Pillar Dam of an Underground Reservoir in Daliuta Mine

Underground reservoir water storage technology has become one important way to achieve efficient coal mining and water resource protection in the western mining areas of China, and the width of coal pillar dams is an important factor affecting the safe operation of underground reservoirs. In order to study the limitations on the reasonable size of a coal pillar dam, Daliuta Mine was selected as the engineering background and a theoretical formula for the reasonable width of a coal pillar dam was proposed. By combining theoretical analysis with numerical simulation analysis, the main influencing factors of the coal pillar dam were compared and analyzed. The research results indicated that changes in the mining height and coal parameters can cause a sharp change in the width of the plastic zone of the dam body. Then, mine water will have an impact on the width of the plastic zone and the width of the elastic core. Moreover, when the width of the coal pillar is smaller than the theoretically calculated width of the coal pillar dam body, the deviator stress and vertical stress inside the dam will significantly increase, and the plastic zone of the dam will significantly expand.

Impacts of Underground Reservoir Site Selection and Water Storage on the Groundwater Flow System in a Mining Area—A Case Study of Daliuta Mine

The natural ecological conditions in the Shendong mining area in China are very fragile, and water resources are seriously lacking. As the production scale of the Shendong mine continues to expand, the demand for water for production and living is also increasing; however, the available surface and underground water is decreasing, and the water scarcity in the Shendong mine is becoming increasingly apparent. Obtaining water resources is a major technological challenge for green mining. The underground reservoir is a new type of underground water conservancy project, and the water shortage in China’s coal mine pits is resolved by underground reservoirs, which also makes a substantial contribution to the effective utilization of water resources. How the construction of underground reservoirs affects the groundwater system in a mining area has become one of the most important factors to consider when finding sites for underground reservoirs. In this study, we took the Daliuta Coal Mine as an example. A numerical model based on the hydrogeological conditions in the mining area was developed to determine the effects on groundwater using FEFLOW software via the finite element method. The model was used to analyze the impacts of coal seam mining thickness, overlying lithology, water-storage range and the water level of the underground reservoir on the groundwater flow system in the mining area. The results indicate that the thickness of the coal seam mining and the lithology of the overlying reservoir both had a significant effect on the upper aquifer system. The water-storage range and water level of the underground reservoirs were the main influences on the lower aquifer system. The results prove that underground reservoir storage had a good effect on water retention in the groundwater system in the mining area, and was able to achieve the desired result of storing groundwater and reducing water loss. It also had a positive feedback effect on the mining area’s environment.

Predicting Overburden-Induced Failure Height of Large Mining Face in Shallow Coal Seam Based on Half-Plane Theory

Research on the overburden-induced failure height in large mining faces is important for solving the problems of sand rupture and water permeability when mining in shallow depth. In order to solve the safety and high-efficiency mining problems, this study used the 7 m-high face #52306 of the Daliuta mine as the object of research for theoretical analysis and field measurements. The results show that the traditional empirical formula is not suitable for predicting overburden on three zones of the large mining face in shallow depth. We use elastic half-plane theory to establish a mechanical model to calculate overburden-induced stress and analyze the law of transmission of abutment pressure in the overburden. We then use maximum shear stress theory to develop a method to predict the height of the overburden in the “three zones” of the mining face based on the law of change in the shear stress. According to the characteristic whereby shear stress at the rear of the working face increases first and then decreases, the area where the shear stress was greater than zero was defined as the zone of water conduction-induced fracture, the area where the shear stress increased was identified as the zone of collapse, and the area where the shear stress decreased was defined as the fracture zone. A comparison of the theoretically calculated values with empirically measured data showed that the relative error was controlled to within 6%, verifying the reliability of the proposed method. The results here can provide useful information for the efficient and environmentally friendly mining of shallow coal seams.

Experimental research on different metamorphic grades of coal bodies with macro–mesoscopic structure fractal characteristics

This paper studies the Daliuta mine, Xinglongzhuang mine, Qingdong mine and Qincheng mine. Here, nuclear magnetic resonance (NMR), mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM) were performed on different metamorphic grades of coal samples from 4 main mining areas in China. The coal body fissure–pore structure parameters were measured in the range of 100 nm∼5000 nm, and the fractal characteristics were obtained for the different metamorphic grades of coal bodies at macro–meso-structure scales, revealing the influence of reservoir formation on the complexity of the coal body structure. The results show that with the increase in metamorphic degree, the ratio of total pore volume occupied by pores and macropores in coal samples gradually decreases, while the volume ratio of transition pores and micropores increases; in addition, the influence of coal reservoir formation processes on fissure–pore structure parameters of coal is obtained. Based on computer graphics theory and fractal geometry theory, the relationship between the 3D volume fractal dimension of the coal bodies, as measured by NMR, MIP and other fluid intrusion methods, and the box-dimension statistical method of SEM to measure the surface fractal dimension is analyzed. The 3D volume fractal dimension calculated by NMR and MIP is consistent with the change in metamorphism degree; that is, with the increase in metamorphism degree of the coal sample, the 3D volume fractal dimension increases. In addition, the 3D volume fractal dimension measured by NMR is larger than that measured by the MIP; the difference between the 3D volume fractal dimension measured by NMR and 2D surface fractal dimension measured by SEM is approximately 1. Here, the influence of reservoir formation on the characteristics of coal structure fractal is obtained. The research results provide important scientific guidance for enhancing coalbed methane recovery and mine disaster prevention.

Analysis of Spatial Variability and Influencing Factors of Soil Nutrients in Western China: A Case Study of the Daliuta Mining Area

An understanding of the spatial variation and influence factors of soil nutrients in mining areas can provide a reference for land reclamation and ecological restoration. Daliuta was used as the study area. The spatial variability of soil nutrients was analyzed using traditional statistics and geostatistics. The effects of topography, mining history, and soil erosion were discussed. The results indicate that the soil pH of the Daliuta mining area is slightly acidic to slightly alkaline, and the soil organic matter, available nitrogen, available phosphorus, and available potassium belonged to the five levels (very low), six (extremely low), five (extremely low), and four (moderately low), respectively. The soil water and salt content indicated that the soil environment in the mining area is arid and has normal levels of salinity. The organic matter, available nitrogen, available phosphorus, available potassium, and soil salt varied moderately, and the pH did not change much, while the soil water varied strongly. The organic matter, pH, and soil salinity are moderately spatially autocorrelated, and the available nitrogen, available phosphorus, available potassium, and soil water are weakly spatially autocorrelated. Each nutrient index had a certain spatial trend effect. The slope, aspect, elevation, and topographic wetness index are the primary topographic factors that control the spatial distribution of soil nutrients. The organic matter, pH, and soil salinity are moderately spatially autocorrelated, and the available nitrogen, available phosphorus, available potassium, and soil water are weakly spatially autocorrelated. Each nutrient index had a certain spatial trend effect. The slope, aspect, elevation, and topographic wetness index are the primary topographic factors that control the spatial distribution of soil nutrients. Soil erosion and mining history are also important factors that lead to the spatial variation of soil nutrients.

Retrieving Three-Dimensional Large Surface Displacements in Coal Mining Areas by Combining SAR Pixel Offset Measurements with an Improved Mining Subsidence Model

Interferometric synthetic aperture radar (InSAR) technology can obtain one-dimensional surface displacements in the radar line of sight (LOS). In the field of mining subsidence, large 3D movements often occur at the same time, and hence InSAR derived one-dimensional LOS displacements can hardly reflect the actual surface motion in mining areas. To realize the monitoring of three-dimensional large surface displacements in mining areas, a method for monitoring three-dimensional large surface displacements in mining areas that combines SAR pixel offset tracking (OT) and an improved mining subsidence model is proposed in this article. First, a new functional relationship between surface subsidence and horizontal movement combined with the characteristics of the overburden rock stress and the deformation characteristics of the fractured rock mass in coal mining areas is established. Then, a three-dimensional surface deformation model is established based on the proposed relationship between surface subsidence and horizontal movement and the radar projection equation, and finally, the optimal parameters of the deformation model are inverted iteratively using LOS deformation results obtained by OT method to retrieve the three-dimensional large displacements of the surface. The significant advantage of the method proposed in this article is that it can accurately acquire the 3D large surface displacements using only two SAR amplitude images with the same imaging geometry. To verify the accuracy and reliability of the proposed algorithm, two scenes of high-resolution spotlight TerraSAR-X images are used in this paper to conduct a three-dimensional surface displacement monitoring experiment on a working panel in the Daliuta mining area in Shaanxi Province, China, based on the proposed method. Experimental monitoring results show that the maximum surface subsidence is approximately 4.5 m, and the maximum horizontal movements in the strike and dip directions are approximately 1.4 m and 1.2 m, respectively. Using GPS measurements to verify the monitoring results, the root mean square error (RMSE) of vertical subsidence is 6.8 cm, and the RMSE of horizontal movement is 7.1 cm. Compared with those in the original mining subsidence model, the accuracies of vertical subsidence and horizontal movement in the proposed model are increased by 28.2% and 37.5%, respectively, which proves the reliability and accuracy of the proposed method.

Numerical Simulation on Failure Rules of Overburden Strata in Shallow Coal Seam

The mining, under the condition of the shallow coal seam, the thick loose beds and the thin base rock in Shendong mining area in Shaanxi province of China, makes the surface subsidence take on the situation of the discontinuous falling crack failure. A great deal of analysis and research indicates that the crack damage is controlled by the key strata in the overburden strata. Therefore, the key for solving the control of mining damage under this condition is to research the rules of the key stratum failure in the shallow seam. Taking 1203 longwall face in Daliuta mine of Shendong mining area as the example, the paper studies the relationship between the stability condition of the key stratum structure and the mining damage, supplying the theoretic evidence for the environmental protection and the confirmation of the reasonable and economical controlled mining methods in Shendong mining area.

Arbuscular mycorrhizal fungal diversity in soils underlying moss biocrusts in coal mining subsidence areas.

The potentially symbiotic mycorrhizal associations dominated by arbuscular mycorrhizal (AM) fungi have become a new topic in bioremediation research in response to global change. Biological soil crusts (biocrusts) play an important role in arid and semi-arid ecosystems. However, AM fungal diversity in the soils underlying moss biocrusts in coal mining subsidence areas remains poorly understood. Here, samples of the soil underlying moss biocrusts in an area inoculated with an AM fungus (AM-BS) and an uninoculated area (CK-BS) plus soil samples from an uninoculated bare area (CK-NBS) were collected from the subsidence area of Shendong Daliuta mine at Yulin, northwest China. AM fungal community diversity indices were maximum in AM-BS, intermediate in CK-BS, and minimum in CK-NBS (P < 0.05). In addition, redundancy analysis (RDA) indicates that the importance of moss biocrust to soil properties followed the sequence: soil water content (SWC) > glomalin-related soil protein (TG) > available phosphorus (Olsen-P) > soil organic matter (SOM) > easily extractable glomalin-related soil protein (EEG) > pH > available nitrogen (alkali-N). SWC, alkali-N, Olsen-P, and SOM were significantly related to the abundance of Glomus and Claroideoglomus, and TG, EEG, and pH were positively related to Diversisipora. In summary, inoculation with the exotic AM fungus and moss biocrust cover created a eutrophic microhabitat for AM fungi in the soils underlying moss biocrusts in the coal mining subsidence area.

Time-Series SBAS Pixel Offset Tracking Method for Monitoring Three-Dimensional Deformation in a Mining Area

The ground surface deformation caused by mining damages the ecological environment and severely hinder economic development in the mining area. The acquisition of three-dimensional ground surface deformation in a mining area helps to improve understanding of the process and mechanism of ground surface deformation caused by mining and helps to prevent and control this type of disaster. In this paper, eleven TerraSAR-X images and five Radarsat-2 images covering the 52304 working face in the Daliuta mining area were used to obtain the time-series line-of-sight (LOS) direction deformation and azimuth direction deformation based on different SAR platforms by application of the small baseline subset (SBAS) pixel offset tracking method. According to the three-dimensional solution principle of multiplatform SAR images and 72 GPS points, the accuracy of deformation in the east-west direction is 0.22 m, while the accuracy in the north-south direction is 0.21 m, with an accuracy of subsidence of 0.34 m.

Research on Surface Failure Law of Working Faces in Large Mining Height and Shallow Buried Coal Seam

In the process of high‐intensity and large‐space mining in Shendong mining area, various surface cracks are generated on the surface, resulting in serious damage to the surface buildings and the local ecological environment. To study the influence of overlying rock movement on surface failure of near‐field single key strata of near‐shallow buried and large mining height working face, the relationship between overburden movement, strata pressure appearance, and surface failure at working face 52307 in Daliuta mining area was analyzed by field measurement and numerical simulation. The results show the following: (1) there is only one thick and hard key stratum in the overburden of large mining height and near‐shallow buried working face. Under the condition of presplitting roof blasting, the first weighting step is still as high as 95 m, and the periodic breaking step of roof is 20–30 m. During the weighting, the working resistance of support is still close to the rated resistance. (2) The single key stratum plays an obvious role in controlling overburden movement. After the first weighting of the working face, a stepped subsidence crack appears on the surface within a short time, and the crack lags behind the working face for about 5 m. (3) During each periodic weighting process, the breaking and subsidence of key blocks are accompanied by surface cracks.

Remote Sensing Monitoring of Soil Moisture in the Daliuta Coal Mine Based on SPOT 5/6 and Worldview-2

Abstract To understand the influence of underground mining disturbances on the shallow soil moisture in the Daliuta coal mine, remote sensing monitoring of the temporal and spatial evolution of surface soil moisture and the influence of mining on multi-source, multi-temporal and high spatial resolution remote sensing data were carried out. The scale effect of monitoring the soil moisture at different scales was analyzed using the Scaled Soil Moisture Monitor Index (S-SMMI). In this paper, SPOT 5/6 and Worldview-2 were used as the data source and mainly made up two aspects of the research: 1) based on the three SPOT data sets with the use of S-SMMI from different angles from the Daliuta mine from nearly three years of soil moisture temporal and spatial changes, the results show that the perturbation has a negative effect on the shallow soil moisture in the Daliuta coal mine, and average soil moisture of the mining area is smaller than the non-mining area, but the surface ecological construction has effectively improved the impact of the underground mining disturbance on the surface soil moisture. 2) the scale conversion of Worldview-2 data was carried out based on the resampling method. S-SMMI was used to analyze the scale effect of soil moisture monitoring at different scales. The results show that the difference between the soil moisture is only 0.0016 during the conversion process of 2 m-30 m.

Research on ground deformation monitoring method in mining areas using the probability integral model fusion D-InSAR, sub-band InSAR and offset-tracking

With the aim of addressing the problem of accurately monitoring complete deformation fields over mining areas by means of Synthetic Aperture Radar (SAR), this paper proposes a solution to obtain complete deformation fields using the probability integral model to fuse deformation data derived from Differential Interferometric SAR (D-InSAR), sub-band InSAR and offset-tracking. This method is used for small-scale, medium-scale and large-scale deformation monitoring using D-InSAR, sub-band InSAR and offset-tracking, respectively. Finally, the probability integral model is utilized to integrate the three deformation fields, and a complete deformation field with high-accuracy over the study area can be obtained. The method is tested on 13 TerraSAR-X (TSX) images from December 2, 2012 to April 24, 2013 of the working face 52,304 of the Daliuta mining area in Shaanxi province, China. The complete deformation field of the working face during the 113-day mining period is obtained. The results show that during the process of working face advancing, the subsidence basin has been expanding along the direction of excavation. The relationship between the average maximum subsidence rate and the advancing distance of the working face can be described by a quadratic polynomial. It has been also observed that, when the underground mining reaches the full mining condition, the maximum subsidence value does not increase further. The accuracy of the proposed method is verified against the global positioning system field survey data. The root mean square errors in the strike and dip directions are 0.134 m and 0.105 m, respectively. Due to the support provide by the reserved coal pillars, the subsidence value above the reserved coal pillars is smaller.

EFFECT OF COAL MINING ON SOIL NITROGEN DISTRIBUTION IN SEMI-ARID MINING AREA OF WESTERN CHINA

Soil nitrogen is a key indicator of soil quality and plays a significant role for plant growth. Therefore, it is very important to study soil nitrogen distribution, especially in semi-arid area of western China. Fewer scholars paid attention to the effect on soil nitrogen due to coal mining in semi-arid mining areas of western China. In this paper, soil samples of different locations were tested in both the loess region and the aeolian sand region in the Daliuta mining area in Shaanxi Province. The impacts of mining subsidence on soil nitrogen were investigated. The soil nitrogen distributions between the loess region and the aeolian sand region were compared, and used the principal component analysis method to evaluate soil quality in semi-arid mining area. The results showed that the comprehensive score of soil quality in the loess region was as follows: the internal pulling stress zone (NLS) &gt; the external pulling stress zone (WLS) &gt; the compressive stress zone (YS) &gt; the neutral zone (ZX). The content of soil total nitrogen in YS-zone was the lowest in the loess region. The loss of nitrogen increased with time in the mining area, in which the total nitrogen loss at the depth of 0−15 cm was 0.27 g/kg, and the alkaline nitrogen loss at the depth of 0−15 cm was 1.08 mg/kg. In the aeolian sand region, the comprehensive score of soil quality was as follows: WLS &gt; FC (the non-mining zone) &gt; ZX &gt; NLS &gt; YS. The amount of soil nitrogen content in the loess region was larger than that in the aeolian sand region. It was found that for the loess region, the relationship between total nitrogen and nitrate nitrogen showed a significant positive correlation. It was also a significant positive correlation between ammonium nitrogen and alkaline nitrogen. In the aeolian sand region, there was a significant positive correlation between total nitrogen and alkaline nitrogen. There was no significant correlation among other nitrogen forms.

采煤沉陷裂缝区土壤含水量变化对柠条叶片叶绿素荧光的响应

PDF HTML阅读 XML下载 导出引用 引用提醒 采煤沉陷裂缝区土壤含水量变化对柠条叶片叶绿素荧光的响应 DOI: 10.5846/stxb201712282341 作者: 作者单位: 中国矿业大学,中国矿业大学,中国矿业大学 环境与测绘学院,中国矿业大学 环境与测绘学院 作者简介: 通讯作者: 中图分类号: 基金项目: 国家重点研发计划课题（2016YFC0501107）；国家重点基础研究发展计划（973）课题（2013CB227904）；国家自然科学基金重点项目（U1361214） Effects of soil water content change on the chlorophyll fluorescence response of Caragana korshinskii leaves under the influence of coal mining subsidence cracks Author: Affiliation: China University of Mining and Technology,China University of Mining and Technology,, Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:采煤塌陷引起的土壤环境因子的变化对矿区植物生长的影响越来越受到人们的关注，快速叶绿素荧光诱导动力学分析技术被称为植物受胁迫状态的有效探针，能够快速获取胁迫下光系统Ⅱ光化学活性和电子传递的信息。研究采煤塌陷裂缝区植物叶片叶绿素荧光的变化是揭示煤炭开采塌陷胁迫对植物个体生长影响的关键环节，能为大尺度下采煤沉陷区植物损伤机理研究提供基础。对于黄土高原半干旱矿区，土壤水分无疑是植物生长最重要的限制因素，而植物叶片叶绿素荧光变化采煤塌陷影响下土壤含水量变化的响应如何尚不清楚。为了弄清采煤沉陷裂缝影响下土壤含水量变化对柠条叶片叶绿素荧光响应的影响，选取神东煤田大柳塔矿区52302工作面为实验场地，在分析了采煤塌陷裂缝对土壤含水量的影响的基础上，以生态修复物种柠条为研究对象，对采煤塌陷裂缝区不同土壤含水量下柠条叶片快速叶绿素荧光诱导动力学曲线进行监测。结果显示：（1）由于煤炭井工开采在地表形成大量裂缝，破坏了土体结构，增加了土壤水分的蒸发面，加速了土壤水的散失。土壤水分含量随着与裂缝之间距离的增加而增加，从距离裂缝0 cm到300 cm，土壤平均含水量从5.63%增加到15.07%；（2）裂缝区土壤水分降低，柠条受到干旱胁迫程度加重，叶片快速叶绿素荧光诱导动力学曲线由O-J-I-P变形为O-K-J-I-P曲线。干旱胁迫通过干扰柠条叶片PSⅡ电子供体侧、受体侧以及电子传递链的功能，严重的损害了柠条叶片光合机构的正常功能。 Abstract:Increased attention has been given to the influence of changes in environmental factors caused by coal mining subsidence on plant physiology. Rapid chlorophyll fluorescence-induced kinetic analysis is known as an effective probe to examine the stress state of plants, using which the information of photochemical activity and electron transfer of light System Ⅱ under stress can be quickly obtained. Studying the change of chlorophyll fluorescence in plant leaves from a coal mining fractured area is a key link for revealing the effects of subsidence stress on individual plant growth, and it can provide the basis for studying the damage mechanism in plants from a mining subsidence area. Soil moisture is undoubtedly the most important limiting factor on plant growth, and the response of chlorophyll fluorescence variation in plant leaves to soil water content under the influence of coal mining subsidence is not clear. In order to ascertain the effects of soil water content on the chlorophyll fluorescence response of Caragana korshinskii under the influence of mining subsidence crack, the 52302 working face of the Daliuta mining area was selected as the experimental site with C. korshinskii as the research target. Based on an analysis of the influence of mining subsidence cracks on soil water content, the fast chlorophyll fluorescence induction kinetics curve of C. korshinskii leaves at different soil moisture contents from the coal mining subsidence fractured area was monitored. The effect of soil water content change on the chlorophyll fluorescence response of C. korshinskii leaves under the influence of coal mining subsidence cracks was studied. The results showed that (1) since coal mining destroys the soil structure, a large number of cracks formed on the surface, which increased the evaporation of surface soil moisture, accelerating the loss of soil water. The soil moisture content increased when the distance between two cracks was from 0 cm to 300 cm, and the average water content increased from 5.63% to 15.07%, respectively. (2) The soil moisture in the fractured area further decreased, and C. korshinskii faced drought stress. The rapid chlorophyll fluorescence induced kinetic curve of the leaves was deformed by O-J-I-P to O-K-J-I-P curves. Drought stress seriously interfered with the normal function of the photosynthetic organs in C. korshinskii leaves by interfering with the functions of the PSⅡ electron donor side, receptor side, and the electron transport chain. 参考文献 相似文献 引证文献

Effect of different inoculation treatments on AM fungal communities and the sustainability of soil remediation in Daliuta coal mining subsidence area in northwest China

Artificial ecological engineering plays an important role in promoting the restoration of mining subsidence areas. To investigate the effects of field inoculation on soil remediation, field studies were conducted in Shendong Daliuta mining area in Yulin, northwest China. Amorpha fruticose plants were treated with under five different inoculations, Funneliformis mosseae (F. m), Rhizophagus intraradices (R. i), F. mosseae and R. intraradices (F. m + R. i), Pantoea sp. (CA), F. mosseae and Pantoea sp. (F. m + CA), as well as no inoculation (CK) as control. The diversity and structure of arbuscular mycorrhizal (AM) fungal communities, glomalin, and soil organic carbon (SOC), available phosphorus, available nitrogen, soil pH were investigated. Based on pyro-sequencing on small subunit ribosomal RNA genes (SSUs), 63 AM fungal operational taxonomic units (OTUs) were identified, which belonged to six genera and two families. F. m + CA inoculation exhibited the highest available phosphorus, the lowest N/P ratio, and higher the ratio between total glomalin-related soil protein (T-GRSP) fractions and soil organic carbon (SOC). Fungal community diversity indices, including Shannon-Wiener, Simpson, and pielou, in F. m inoculation were significantly lower than others, and the phylogenetic index in F. m + CA inoculation was the highest (P < 0.05). In addition, Permutational multivariate analysis of variance (PerMANOVA) and non-metric multidimensional scaling (NMDS) analyses showed that the distribution of AM fungal communities without F. m inoculation were not significantly different from CK. These results demonstrated that the diversities and structures of AM fungal communities were sensitive indicators for monitoring the environmental changes in subsidence area. Furthermore, structural equation model (SEM) showed that AM fungal diversity had direct effects on T-GSRP. In summary, field inoculation of Amorpha fruticose plants had a valid effect on soil remediation, and F. m + CA inoculation is the befitting combination for soil restoration in the experimental field.

Application of magnetotelluric method to the detection of overburden failure height in shallow seam mining

This paper studies the reliability of magnetotelluric (MT) method detection for overburden failure (OF) height in shallow seam mining. According to the geological conditions of the 52,505 working face in the Daliuta mine, five observation lines have been designed to detect the apparent resistivity (AR) of the overburden before and after mining. Analyzed the characteristic points of the face and the AR of the overburden on the main section and studied the characteristics of AR for various overburden lithologies. The AR of the overlying strata corresponding to different failure conditions is also different. Further obtained the height of the caved zone (CZ) on the working face was 25.6 m, and the height of the water flowing fracture zone (WFFZ) was 82.5 m. Finally adopted the numerical simulation and an empirical formula for calculation to validate the MT detection results and proved that it was reliable to use the MT method to detect OF height, thus providing a convenient, fast, economical, and reliable method for detecting OF heights when mining in shallow seams.

Vegetation recovery and groundwater pollution control of coal gangue field in a semi-arid area for a field application

This paper studied the impact of a gully-type gangue dump in the Daliuta mine area, Shaanxi, China on the groundwater environment and its contamination control. Multiple methods including eco-hydrogeological survey, soil column leaching test, field test and groundwater flow analysis were applied in the study. According to the field survey, the stack of gangue had changed the original feature of groundwater flow system, with the groundwater level of the gangue field raising about 1–3 m compared with the condition before the establishment of gangue dump. The long-term immersion of gangue had released various harmful substance into the groundwater and affected the downstream areas. The leaching test showed that the loess could significantly purify the mine wastewater by increasing pH value from 4.5 to 6.2–6.7 and absorbing heavy metals. Based on the loess column test, two loess permeable reactive barriers (LPRBs) were established in situ to improve the groundwater environment of gangue field. Besides, the vegetation restoration had been successfully carried out by covering a 30 cm-thick loess layer on the coal gangues and planting Alfalfa and Artemisica ordosica to improve the ecological environment, and the vegetation coverage had increased from 10% in 2008 to about 65% in 2013.