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With the development, a relatively perfect policy system has been gradually established for mine ecological protection and restoration in China based on the two contexts of mine land reclamation and mine geological environment protection and restoration. strengthen source control and promote green mine construction; Second, comprehensively promote system protection and restoration; Third, accelerate ecological and environmental governance in key areas and regions; Fourth, improve the ecological compensation system and financial support policy Fifth, promote the establishment of market-based mechanisms and encourage and incentivize the participation of private capital. Based on the current policy orientation and problems existing in practice, this paper puts forward fund guarantee system for mine ecological restoration, improving the implementation rules of the market-oriented operation support policy for projects, promoting the standardization of mine ecological restoration standards and working procedures, and optimizing the whole life cycle management system for new and production mines. [ABSTRACT FROM AUTHOR]

The optimal reuse of abandoned mining land is of great practical significance to construct and expand the space that required by the transformation of resource-based towns in China. Taking Mentougou District of Beijing as an example, the 3S technology and field research were integrated to analyze the type, area, distribution, reuse status, as well as the temporal and spatial changes of abandoned mining land. A dynamic environment model of geographical process (Dinamica EGO) was used to simulate the reuse pattern of abandoned mining land under the trend development scenario. The appropriateness of abandoned mining land was evaluated to reuse for the ecological agriculture, ecological tourism, and high-tech industry under the functional positioning of “Capital ecological conservation development area” of Mentougou District using principal component analysis and BP neural network. According to the suitability evaluation and the land needs of industrial transformation, the land conversion rules were established to optimize the quantitative structure using the linear niche programming model and constraint conditions. Dinamica EGO model was then used to optimize the spatial pattern of the abandoned mining land that reused for the industrial transformation. Regulation was conducted to compare the optimization pattern with the trend development. The results showed were as follows: 1) A total of 323.30 hm2 of abandoned mining land was reused in the study area from 2006 to 2018. The abandoned mining land in the western towns was mainly reused as the woodland, cultivated land and orchards, while the abandoned mining land in eastern towns was mainly reused as the woodland, park, residential, and high-tech industrial land. 2) In the trend development scenario pattern, the abandoned mining land reused as ecological agricultural land was mainly distributed in Miaofengshan and Tanzhesi Town, the ecological tourism industry was mainly distributed in Datai Street and Wangping Town, and the high-tech industrial land was in Datai Street and Junzhuang Town. In the optimized pattern of abandoned mining land reuse for the industrial transformation, the area of abandoned mining land reused as the ecological agriculture was 251.75 hm2, mainly concentrated in Junzhuang, and Wangping Town, the reused area of the ecotourism was 67.25 hm2 in Miaofengshan, and Qingshui Town, and the area as the high-tech industry was 84.25 hm2 in Wangping and Miaofengshan Town. 3) In the two scenarios, about 108.5 hm2 of abandoned mining land was reused for the same purpose, indicating no adjustment to need. About 63.75 hm2 of abandoned mining land was reused as the ecological tourism land under the trend development scenario, which should be adjusted to the ecological agriculture land. By contrast, the ecological agriculture land was about 61 hm2 of abandoned mining land under the trend development scenario, which should be adjusted to the ecological tourism land. There was the 12.5 hm2 abandoned mining land should be developed into the high-tech industrial land in the Miaofeng Mountain, Wangping, and Yongding Town, according to the local infrastructure. Consequently, the direct and substantial combination were realized for the reuse of abandoned mine land and the demand for the industrial transformation of mineral resource-based towns. The findings can provide the theoretical support for the reuse and regulation of local abandoned mine land. [ABSTRACT FROM AUTHOR]

To achieve the effective monitoring of rock failure events in the mine water inrush inoculation process, a moment tensor inversion method based on digital seismology was introduced to process abnormal microseismic events monitored in Hebei Fanshan Phosphate Mine. The vibration displacement field in the mine scale could be expressed as the convolution of moment tensor and Green's function. The moment tensor was linearly inversed through extracting displacement data from the microseismic events and calculating the Green's function (pulse response of transmission medium between the source and sensors). Then, the type of ruptures was distinguished by analyzing the fracture azimuth of microseismic events. As a result, a 3D effect picture of the microseismic monitoring area was built to fit the rock failure surface, predict its development trend, and demarcate the water inrush danger zone preliminarily. Research results show that the moment tensor inversion method can be used to calculate a series of focal mechanism solutions and can reflect the rock failure in the mine water inrush inoculation pocess and development trend effectively.

In the industrial and mining land reclamation area, the strong topographic relief, the diversity, breakage, mixed distribution and scattered layout of the surface features and other factors cause the difficulties for remote-sensing image classification mapping. In order to improve the classification accuracy for land use of industrial and mining reclamation area and provide data support for land reclamation monitoring and supervision, this article explored the classification method based on grid-search and random forest algorithm for the reclamation area. Satellite and auxiliary dataset including GF-1 images, DEM (digital elevation model) and field investigation data were acquired in October 2016. The study area was Gulin County, Luzhou City, Sichuan Province. In order to obtain the real surface reflectance and reduce the atmospheric and environmental effects from the satellite images in this study, FLAASH atmospheric correction and geometric correction were used in the satellite image pre-processing with ENVI 5.3 software. A machine learning algorithm, random forest algorithm, was used because the method facilitated the use of ancillary data in classification. Feature selection was an important preprocessing step in many machine learning applications, which selected the smallest subset of relevant features that built robust learning models. In the paper, spectrum, topography, texture and space variables were included in feature selection, in order to differentiate the built-up areas and farmlands, and BCI (biophysical composition index) was calculated in spectrum features. Texture feature processing comprised principal component analysis. Local Moran' I reflecting spatial autocorrelation feature and Local Getis Ord Gi reflecting hotspot feature were selected to improve the result of classification further. The grid-search method based on OOB (Out-of-Bag) error was used to optimize parameter. Based on data image spectrum, topography, texture, space and other information, 33 feature variables were figured out from the feature selection step, and 4 combined models were constructed to carry out random forest classification experiment; and the precision was 82.79%, 84.91%, 86.75% and 88.16% respectively. To eliminate the redundant information in the 33 feature variables and reduce the image band dimensionality, the study adopted variable importance estimation and Relief F algorithm to select the principle feature variables to conduct classification according to random forest algorithm. Through the comparison between the Model 2, Model 4, SVM (support vector machine) and MLC (maximum likelihood classification) classification result respectively, the study indicates that the random forest algorithm based on grid-search parameter optimization can achieve the classification accuracy of 88.16% in the multi-feature variables frame. After different methods are used to reduce the dimension of variables, the classification accuracy can also be kept above 85%, and the accuracy is higher than SVM and MLC classification results under the same number of feature variables. The random forest classifier is superior to SVM and more capable of dealing with multidimensional characteristic variables. The random forest method based on grid-search can obtain high precision in land use classification applied in reclamation area. Based on this method, remote sensing image interpretation can well provide the technical support and rational reference for land reclamation monitoring and supervision. [ABSTRACT FROM AUTHOR]

Abandoned land is a special kind of land space which is damaged by industrial and mining activities. Due to being abandoned for a long time, complicated formation and uncertain factors, the improvement of soil fertility and quality during abandoned land reclamation requires a long process. So tracking monitoring and evaluation work is really important. A making method of tracking monitoring scheme for abandoned land reclamation includes the layout of monitoring points, the establishment of the minimum data set of monitoring indicators, as one of the means of monitoring soil, surface water, groundwater and crop. A case study on a reclamation project of an abandoned sulfur mine land was carried out in the southwest area of China. With the help of 3S (remote sensing, RS; geographical information system, GIS; global positioning system, GPS) and geostatistics, we proposed monitoring point layout scheme, and monitoring indicators, and established the minimum data set as one of the means for soil, groundwater, surface water and plant. Considering the reclamation measures and monitoring index of spatial heterogeneity and the reclaimed land quality evaluation results, multi-layer spatial overlap was adopted to form monitoring units and monitoring points; considering the existing land reclamation quality factors and variability, through the analysis of the existing index average value, the single pollution index, exceeding rate, rhichness and rangeabilty to obtain the minimum data set of monitoring indicators. The monitoring sites of reclaimed soil, crop, ground water, and surface water were 53, 5, 5 and 1, and 2 kinds of monitoring types were collected. A minimum data set of 15 indicators was constructed, covering the quality of construction, environment, soil fertility, and so on. The reliability of the monitoring points was validated and evaluated from the monitoring point number and spatial layout using the coefficient of variation, relative deviation, variable range of variation function and Moran’s Index according to the monitoring scheme proposed in the paper. The evaluation results showed that the number of monitoring points obtained according to monitoring scheme was close to the number in verification calculation, which met the requirements. Compared with the 138 samples in 2015, the number of monitoring points decreased by 61.59%, the monitoring index was reduced by more than 50%, the distribution of monitoring points was more uniform, the monitoring content was more comprehensive, and the monitoring cost was saved; the actual sampling distance (average 456 m) did not exceed the monitoring index range of variation function, and there was no need to refine the monitoring unit or monitoring point; the spatial distribution characteristics of monitoring points were random or between clustered and random, which was not significant (P>0.05), and the monitoring points layout was ideal. This shows that the making method of tracking monitoring scheme is scientific and feasible. The tracking monitoring scheme can guide the quality improvement project for the reclamation of abandoned mine land and also provide a technical support and empirical basis for developing the tracking monitoring standards of abandoned land reclamation. [ABSTRACT FROM AUTHOR]

Waste land reclamation potential in mine areas is an important basis for a Land Consolidation and Rehabilitation Plan. The size of potential value calls for the evaluation, so the selection of evaluation methods has a direct impact on the result of the evaluation. In general, the steps of reclamation evaluation are choosing the evaluation objects, screening evaluation indices, grading the evaluation indices, weighted the indices, and evaluating the potential. In the current study, most research uses just one method to evaluate the reclamation potential, or improve the method during the process of reclamation evaluation, like improving the method for obtaining weight, and taking this as the final evaluation result may introduce a kind of randomness. Based on the Shuozhou city in Pinglu area in Shanxi Province, this article will use the Index method, the Fuzzy comprehensive evaluation method, and the Artificial neural network model to evaluate the reclamation potential, and discuss the similarities, differences, and the lead reasons among the results provided by these three methods. Then, the Analytic Hierarchy Process is used to combine the results from each method, and the comprehensive evaluation result is obtained based on that. The result indicates that under the same index system and weight, because of the different evaluation methods and the different dimensionless methods used during these processes, each potential level is different among the numbers of figure spot, area, and spatial location under the same potential level. Under the theory that both the Index method and Fuzzy comprehensive evaluation method are affected by the indicator system and weight, the difference is that before using the Index method, the experimentalist should standardize parameter values, which will be solved during the Fuzzy comprehensive evaluation process. The similarity is that both methods will provide weighted sums of the indicator system to obtain the final value, which will be a numerical value whose size represents the potential level by the Index method, while the result by the Fuzzy comprehensive evaluation method is a row vector. This paper depends on the weighted average principle to get the potential level. As for the artificial neural network model, after normalizing all parameters, because the value for each node in the hidden layer and output layer, instead of the simple weighted sum, is calculated, the whole process is dependent on its self-learning capability. So, whereas the artificial neural network model is little influenced by subjectivity, the result by the artificial neural network model is more objective. The comparison between the waste land distribution and the comprehensive evaluation result indicates that where the abandoned mining areas and mining consolidation areas are concentrated in the first or second level, the potential is overall high. Where the mined areas stay in the third or fourth level, the potential is relatively low. Research shows that the comprehensive evaluation result is more scientific and has a more objective theoretical value; and for the waste land system, the actual value calculated still needs to include values for the reclamation years, funds, personnel organization, property right relations, and other factors. [ABSTRACT FROM AUTHOR]

Topographic reconstruction is a crucial part of land reclamation and ecological rehabilitation because the resulting geography landscapes are the foundations for all subsequent reclamation practices and the surfaces for future land uses. It is also ranked among the most important research technical problems. Nature can provide analogues for mined or mining landscapes during disturbed-land reclamation according to landscape stability and according to the reconstructed structure blending in with the surrounding undisturbed landscape. In terms of the watershed geomorphology and the principle of self-similarity theory, the sub-catchments and channels of abandoned mines were re-planned by using ArcGIS soft technology and a practical survey in this paper. At the same time, the topography characteristics of adjacent, undisturbed catchments were calculated by applying an ArcGIS Hydrologic analysis tool, which was taken as the following simulation reference standard. Then the topography in a sub-watershed unit in the Huangyuan abandoned quarry project of Fangshan county in Beijing city was reconstructed by using a Geofluv (Natural Regrade) module driven by geomorphic principles, in which this module simulated the function of the natural landscape that would evolve over time under the physical and climatic conditions present at the site to water and sediment from the land surface in a stable hydrologic equilibrium. Moreover, the theory and technical method of the reconstructed topography were studied. The initial study of the sub-watershed on the undisturbed landform in the project's vicinity were selected and calculated to develop a stable channel design and reconstruction guidelines by using GIS spatial analysis tools, and the selected geomorphologic characteristics index were first and second order sub-watershed, the average sub-watershed area, main channel, drainage density, watershed roundness, average elevation difference, and average slope, which provided targets for topographic reconstruction. In this case, the average second order drainage density that represented the stable sub-watershed size for the local condition was 13.84km/km2. Moreover, the average second order drainage density of the reconstructed topography which simulated the natural landform evolution to the stage in balance with the local environmental condition was 14.52km/km2 on the basis of a re-planning of reconstruction sub-watershed and main channel, which achieved the desired design goals. The results showed that the reconstructed Huangyuan topography in which the hydrologic and fluvial geomorphic analyses and stable channel parameters were determined, and based on site-specific data, were relatively economical, stable, and natural, which was similar to the undisturbed catchments' geomorphology. Finally, the relationship of geomorphologic characteristics between the reconstructed sub-watershed and the undisturbed ones was analyzed and the ratio of the index was almost similar. A topographic reconstruction simulated a relatively stable sub-watershed performed by geomorphic processes with the creation of a basin composed of slope and channels in orderly spatial arrangements and functioning for the transportation of water and sediment. The geomorphic information entropy analysis showed that the geomorphology changed very slowly after topographic reconstruction and the erosions on watershed were also gradually reduced. This study provided a novel viewpoint for the topographic reconstruction of an abandoned mine. [ABSTRACT FROM AUTHOR]