The purpose of this study was to prepare a cropland suitability map of Mongolia based on comprehensive landscape principles, including topography, soil properties, vegetation, climate and socio-economic factors. The p...The purpose of this study was to prepare a cropland suitability map of Mongolia based on comprehensive landscape principles, including topography, soil properties, vegetation, climate and socio-economic factors. The primary goal was to create a more accurate map to estimate vegetation criteria (above ground biomass AGB), soil organic matter, soil texture, and the hydrothermal coefficient using Landsat 8 satellite imagery. The analysis used Landsat 8 imagery from the 2016 summer season with a resolution of 30 meters, time series MODIS vegetation products (MOD13, MOD15, MOD17) averaged over 16 days from June to August 2000-2016, an SRTM DEM with a resolution of 30 meters, and a field survey of measured biomass and soil data. In total, 6 main factors were classified and quality evaluation criteria were developed for 17 criteria, each with 5 levels. In this research the spatial MCDM (multi-criteria decision-making) method and AHP based GIS were applied. This was developed for each criteria layer’s value by multiplying parameters for each factor obtained from the pair comparison matrix by the weight addition, and by the suitable evaluation of several criteria factors affecting cropland. General accuracy was 88%, while PLS and RF regressions were 82.3% and 92.8%, respectively.展开更多
Non-erodible elements such as stones and vegetation are key to controlling wind erosion and dust emission in drylands.Stony deserts are widely distributed in the Gobi Desert,but the effect of stones on wind erosion an...Non-erodible elements such as stones and vegetation are key to controlling wind erosion and dust emission in drylands.Stony deserts are widely distributed in the Gobi Desert,but the effect of stones on wind erosion and dust emission have not been well studied,except under artificial conditions.In this study,we evaluated the effect of stones on wind erosion and dust emission by measuring the sand saltation threshold in a stony desert in Tsogt-Ovoo in the Gobi Desert,Mongolia,under natural surface conditions during sand and dust storms.We quantified the amount of stones by measuring the roughness density,and determined the threshold friction velocity for sand saltation by measuring wind speed and sand saltation count.Our results showed that the threshold friction velocity increased with the roughness density of stones.In the northern part of the study area,where neither a surface crust nor vegetation was observed,the roughness density of stones was 0.000 in a topographic depression(TD),0.050 on a northern slope(N.SL),and 0.160 on the northern mountain(N.MT).The mean threshold friction velocity values were 0.23,0.41,and 0.57 m/s at the TD,N.SL,and N.MT sites,respectively.In the southern part of the study area,the roughness density values of stones were 0.000 and 0.070-0.320 at the TD and southern slope sites,respectively,and the mean threshold friction velocities were 0.23 and 0.45-0.71 m/s,respectively.We further compared the observed threshold friction velocities with simulated threshold friction velocities using Raupach's theoretical roughness correction and the measured roughness density values,and found that Raupach's roughness correction worked very well in the simulation of threshold friction velocity in the stony desert.This means that the results of our stone measurement can be applied to a numerical dust model.展开更多
In next two years, the current waste dump of Narynsukhait coal mine is predicted insufficient to accommodate the overburden as limited of the waste dump capacity. Thus, redesigning waste dump is paramount to increase ...In next two years, the current waste dump of Narynsukhait coal mine is predicted insufficient to accommodate the overburden as limited of the waste dump capacity. Thus, redesigning waste dump is paramount to increase capacity of the dump in future. This paper describes current condition of waste dump of Narynsukhait coal mine and then discusses the optimization of waste dump geometry by analyzing the effect of different waste dump’s bench configuration on slope performance. Optimization of the geometry is carried out by investigating and comparing the performance of geometrical combinations of bench height, bench angles and number of safety berm by means of numerical modeling. The model shows that increasing height of bench is able to induce shear stress in the bench and may initiate bench instable. However, the shear stress can be limited by having safety berm and/or reducing bench angle to satisfy the stability criteria.展开更多
Berau Basin, a sub-basin of Tarakan Basin, had been developed during Eocene to Miocene period. Rocks in Berau Basin consist of sedimentary, volcanic and igneous rocks aged from Pre-tertiary until Quaternary epoch. The...Berau Basin, a sub-basin of Tarakan Basin, had been developed during Eocene to Miocene period. Rocks in Berau Basin consist of sedimentary, volcanic and igneous rocks aged from Pre-tertiary until Quaternary epoch. The youngest identified rock formation was alluvial deposit consists of mud, silt, sand, gravel and swamp with brown to dark color. This youngest rock formation is relatively weak geological condition and can cause problems in the coal mining operation. PT Berau Coal as one of the coal mining companies in Berau Basin area had experienced some problems related to the occurrence of alluvial deposit. A large failure has occurred at one of its out pit dumping?area which lies over the swamp material. The failure caused a higher operating cost since it made that the distance for waste rock dumping became to be farther than the designated area. Therefore, in order to prevent similar failure occurring at dumping area which lies above swamp material, an improvement of dumping site stability on weak geological condition has to be needed. The proposed method for improving the stability of out pit dumping area in weak geological condition is to construct the compacted layer of waste rock before the out pit dumping area construction. Based on experimental results, a minimum of 40 kPa pressure is needed to give a proper compaction to the waste rock. The result of numerical analysis by Finite Element Method (FEM) shows that construction of compacted layer on the base of out pit dumping area can improve its stability.展开更多
Regardless of beneficial associated with internal waste dump (IWD) method, practices of this method within boundaries of pit-slope have some serious problems on stability issues due to this area is zone of potential f...Regardless of beneficial associated with internal waste dump (IWD) method, practices of this method within boundaries of pit-slope have some serious problems on stability issues due to this area is zone of potential failure. This zone is known as dynamic reactive zone which is easy to deform by external force, and inherent dangers of failure posing a threat to slope. Therefore, it is paramount to study the induced shear stress behavior in this zone particularly when IWD method is adopted within this zone. In this paper, a numerical study for investigating IWD-induced shear stress behavior has been carried out using Finite Element Method (FEM) with Strength Reduction approach. Different scenarios as per pit-slope depths, IWD heights and buffer zone lengths have been accounted and simulated using PHASE 2 to understand changes in induced shear stress imposed on the pit-slope. It is found that shear stress imposed on pit slope seems change dramatically with increasing IWD height for case of buffer zone length is less than 100-m-long.展开更多
At present, air pollution has become the main problem in many developed and developing countries. Especially, in Ulaanbaatar city of Mongolia, it has become one of the most tackled issues of every citizen living in th...At present, air pollution has become the main problem in many developed and developing countries. Especially, in Ulaanbaatar city of Mongolia, it has become one of the most tackled issues of every citizen living in the capital city. The aim of this study is to highlight the trend of air pollution and pollution sources in the Mongolian capital and conduct some air pollution analyses. Overall, the study indicates that the air pollution in Ulaanbaatar city is a very serious problem and for its reduction, rapid and thorough measures should be taken.展开更多
In recent years, development of a proper country-specific height system has become a major challenge for the scholars and specialists working in the field of geodesy. The National Geodetic Services of many countries a...In recent years, development of a proper country-specific height system has become a major challenge for the scholars and specialists working in the field of geodesy. The National Geodetic Services of many countries are trying to establish a new system that can provide the customers and decision-makers with high accuracy basic geodetic data obtained by modern satellite measurements. Although, Mongolia has a long tradition with geodesy and land surveying, the country still lacks a refined height system that can be effectively used for mapping and other purposes. In the present study, we tried to solve the problem related to the Mongolian height system using of a modern satellite technology. The research had some very important results: 1) evaluation of the main height network and height system of Mongolia, 2) development of a new method for calculating the normal height system in Mongolia, and 3) creation of the height unified system by considering surface potential of the global ellipsoidal level as normal.展开更多
The aim of this research is to apply TerraSAR X-band, Envisat C-band and Palsar L-band synthetic aperture radar (SAR) images for a knowledge acquisition process. For the study, backscattering properties of different n...The aim of this research is to apply TerraSAR X-band, Envisat C-band and Palsar L-band synthetic aperture radar (SAR) images for a knowledge acquisition process. For the study, backscattering properties of different natural and man-made objects of urban environment are analyzed on the basis of statistics of signatures of the selected classes. After the knowledge acquisition, for the acquired knowledge representation, a rule-based approach is proposed. Overall, the research demonstrated that the multi-frequency radar images can be effectively used for the knowledge acquisition as well as for the analysis of different land cover types.展开更多
The aim of this study is to fuse high resolution optical and microwave images and classify urban land cover types using a refined Mahalanobis distance classifier. For the data fusion, multiplicative method, Brovey tra...The aim of this study is to fuse high resolution optical and microwave images and classify urban land cover types using a refined Mahalanobis distance classifier. For the data fusion, multiplicative method, Brovey transform, intensity-huesaturation method and principal component analysis are used and the results are compared. The refined method uses spatial thresholds defined from local knowledge and the bands defined from multiple sources. The result of the refined Mahalanobis distance method is compared with the result of a standard technique and it demonstrates a higher accuracy. Overall, the research indicates that the combined use of optical and microwave images can notably improve the interpretation and classification of land cover types and the refined Mahalanobis classification is a powerful tool to increase classification accuracy.展开更多
0Introduction The Bayankhongor ophiolite zone,a NW-SE strik ing linear structure 400 km long and up to 25 km wide,i the largest ophiolite association in Central Mongolia and possibly in all of Central Asia.The Bayankh...0Introduction The Bayankhongor ophiolite zone,a NW-SE strik ing linear structure 400 km long and up to 25 km wide,i the largest ophiolite association in Central Mongolia and possibly in all of Central Asia.The Bayankhongor cop展开更多
文摘The purpose of this study was to prepare a cropland suitability map of Mongolia based on comprehensive landscape principles, including topography, soil properties, vegetation, climate and socio-economic factors. The primary goal was to create a more accurate map to estimate vegetation criteria (above ground biomass AGB), soil organic matter, soil texture, and the hydrothermal coefficient using Landsat 8 satellite imagery. The analysis used Landsat 8 imagery from the 2016 summer season with a resolution of 30 meters, time series MODIS vegetation products (MOD13, MOD15, MOD17) averaged over 16 days from June to August 2000-2016, an SRTM DEM with a resolution of 30 meters, and a field survey of measured biomass and soil data. In total, 6 main factors were classified and quality evaluation criteria were developed for 17 criteria, each with 5 levels. In this research the spatial MCDM (multi-criteria decision-making) method and AHP based GIS were applied. This was developed for each criteria layer’s value by multiplying parameters for each factor obtained from the pair comparison matrix by the weight addition, and by the suitable evaluation of several criteria factors affecting cropland. General accuracy was 88%, while PLS and RF regressions were 82.3% and 92.8%, respectively.
基金This study was supported by the Arid Land Research Center's Project(Impacts of Climate Change on Drylands:Assessment and Adaptation,funded by the Japan's Ministry of Education,Culture,Sports,Science,and Technology)the Grants-in-Aid for Scientific Research(JSPS KAKENHI)(15H05115,17H01616,16H02712,and 25220201)+1 种基金the Environment Research and Technology Development Fund of the Environmental Restoration and Conservation Agency(JPMEERF20205001)This study was funded by the Joint Research Program of Arid Land Research Center,Tottori University(31C2003 and 31C2012).
文摘Non-erodible elements such as stones and vegetation are key to controlling wind erosion and dust emission in drylands.Stony deserts are widely distributed in the Gobi Desert,but the effect of stones on wind erosion and dust emission have not been well studied,except under artificial conditions.In this study,we evaluated the effect of stones on wind erosion and dust emission by measuring the sand saltation threshold in a stony desert in Tsogt-Ovoo in the Gobi Desert,Mongolia,under natural surface conditions during sand and dust storms.We quantified the amount of stones by measuring the roughness density,and determined the threshold friction velocity for sand saltation by measuring wind speed and sand saltation count.Our results showed that the threshold friction velocity increased with the roughness density of stones.In the northern part of the study area,where neither a surface crust nor vegetation was observed,the roughness density of stones was 0.000 in a topographic depression(TD),0.050 on a northern slope(N.SL),and 0.160 on the northern mountain(N.MT).The mean threshold friction velocity values were 0.23,0.41,and 0.57 m/s at the TD,N.SL,and N.MT sites,respectively.In the southern part of the study area,the roughness density values of stones were 0.000 and 0.070-0.320 at the TD and southern slope sites,respectively,and the mean threshold friction velocities were 0.23 and 0.45-0.71 m/s,respectively.We further compared the observed threshold friction velocities with simulated threshold friction velocities using Raupach's theoretical roughness correction and the measured roughness density values,and found that Raupach's roughness correction worked very well in the simulation of threshold friction velocity in the stony desert.This means that the results of our stone measurement can be applied to a numerical dust model.
文摘In next two years, the current waste dump of Narynsukhait coal mine is predicted insufficient to accommodate the overburden as limited of the waste dump capacity. Thus, redesigning waste dump is paramount to increase capacity of the dump in future. This paper describes current condition of waste dump of Narynsukhait coal mine and then discusses the optimization of waste dump geometry by analyzing the effect of different waste dump’s bench configuration on slope performance. Optimization of the geometry is carried out by investigating and comparing the performance of geometrical combinations of bench height, bench angles and number of safety berm by means of numerical modeling. The model shows that increasing height of bench is able to induce shear stress in the bench and may initiate bench instable. However, the shear stress can be limited by having safety berm and/or reducing bench angle to satisfy the stability criteria.
文摘Berau Basin, a sub-basin of Tarakan Basin, had been developed during Eocene to Miocene period. Rocks in Berau Basin consist of sedimentary, volcanic and igneous rocks aged from Pre-tertiary until Quaternary epoch. The youngest identified rock formation was alluvial deposit consists of mud, silt, sand, gravel and swamp with brown to dark color. This youngest rock formation is relatively weak geological condition and can cause problems in the coal mining operation. PT Berau Coal as one of the coal mining companies in Berau Basin area had experienced some problems related to the occurrence of alluvial deposit. A large failure has occurred at one of its out pit dumping?area which lies over the swamp material. The failure caused a higher operating cost since it made that the distance for waste rock dumping became to be farther than the designated area. Therefore, in order to prevent similar failure occurring at dumping area which lies above swamp material, an improvement of dumping site stability on weak geological condition has to be needed. The proposed method for improving the stability of out pit dumping area in weak geological condition is to construct the compacted layer of waste rock before the out pit dumping area construction. Based on experimental results, a minimum of 40 kPa pressure is needed to give a proper compaction to the waste rock. The result of numerical analysis by Finite Element Method (FEM) shows that construction of compacted layer on the base of out pit dumping area can improve its stability.
文摘Regardless of beneficial associated with internal waste dump (IWD) method, practices of this method within boundaries of pit-slope have some serious problems on stability issues due to this area is zone of potential failure. This zone is known as dynamic reactive zone which is easy to deform by external force, and inherent dangers of failure posing a threat to slope. Therefore, it is paramount to study the induced shear stress behavior in this zone particularly when IWD method is adopted within this zone. In this paper, a numerical study for investigating IWD-induced shear stress behavior has been carried out using Finite Element Method (FEM) with Strength Reduction approach. Different scenarios as per pit-slope depths, IWD heights and buffer zone lengths have been accounted and simulated using PHASE 2 to understand changes in induced shear stress imposed on the pit-slope. It is found that shear stress imposed on pit slope seems change dramatically with increasing IWD height for case of buffer zone length is less than 100-m-long.
文摘At present, air pollution has become the main problem in many developed and developing countries. Especially, in Ulaanbaatar city of Mongolia, it has become one of the most tackled issues of every citizen living in the capital city. The aim of this study is to highlight the trend of air pollution and pollution sources in the Mongolian capital and conduct some air pollution analyses. Overall, the study indicates that the air pollution in Ulaanbaatar city is a very serious problem and for its reduction, rapid and thorough measures should be taken.
文摘In recent years, development of a proper country-specific height system has become a major challenge for the scholars and specialists working in the field of geodesy. The National Geodetic Services of many countries are trying to establish a new system that can provide the customers and decision-makers with high accuracy basic geodetic data obtained by modern satellite measurements. Although, Mongolia has a long tradition with geodesy and land surveying, the country still lacks a refined height system that can be effectively used for mapping and other purposes. In the present study, we tried to solve the problem related to the Mongolian height system using of a modern satellite technology. The research had some very important results: 1) evaluation of the main height network and height system of Mongolia, 2) development of a new method for calculating the normal height system in Mongolia, and 3) creation of the height unified system by considering surface potential of the global ellipsoidal level as normal.
文摘The aim of this research is to apply TerraSAR X-band, Envisat C-band and Palsar L-band synthetic aperture radar (SAR) images for a knowledge acquisition process. For the study, backscattering properties of different natural and man-made objects of urban environment are analyzed on the basis of statistics of signatures of the selected classes. After the knowledge acquisition, for the acquired knowledge representation, a rule-based approach is proposed. Overall, the research demonstrated that the multi-frequency radar images can be effectively used for the knowledge acquisition as well as for the analysis of different land cover types.
文摘The aim of this study is to fuse high resolution optical and microwave images and classify urban land cover types using a refined Mahalanobis distance classifier. For the data fusion, multiplicative method, Brovey transform, intensity-huesaturation method and principal component analysis are used and the results are compared. The refined method uses spatial thresholds defined from local knowledge and the bands defined from multiple sources. The result of the refined Mahalanobis distance method is compared with the result of a standard technique and it demonstrates a higher accuracy. Overall, the research indicates that the combined use of optical and microwave images can notably improve the interpretation and classification of land cover types and the refined Mahalanobis classification is a powerful tool to increase classification accuracy.
文摘0Introduction The Bayankhongor ophiolite zone,a NW-SE strik ing linear structure 400 km long and up to 25 km wide,i the largest ophiolite association in Central Mongolia and possibly in all of Central Asia.The Bayankhongor cop
