Reclamation Techniques Research Articles

Tillage and Its Effect on Agricultural Soils: A Quality Index Approach

The growing demand for quality food has intensified agricultural practices, thus deteriorating soil fertility. In response, reclamation techniques such as minimum, zero, or no tillage have been applied, especially in the Bajio region of the State of Guanajuato, Mexico. However, a reliable tool to evaluate the effectiveness of these techniques remains elusive. This study evaluated the effect of zero tillage and conventional tillage by developing a Soil Quality Index (SQI) from eight agricultural soils in the Bajio region. A set of 26 physicochemical indicators was used, reducing them by means of principal component analysis (PCA). Subsequently, the SQI methodology called “unified weighted” was applied. The resulting SQIu included key indicators such as C/N, SND, ESP, and Fe. Although significant differences in soil quality were observed among the samples tested, the SQIu was unable to discern soil quality under the different tillage schemes. This may be attributed to the limited application time of zero tillage, which might not be sufficient to achieve significant recovery of SQI indicators. Nevertheless, the SQIu could be useful as a monitoring tool to evaluate the progress of soil recovery under zero tillage, both in the studied area and in similar contexts at the national or international level.

Optimizing refuse-derived fuel production: a review of pre-treatment techniques for municipal solid waste reclamation

Optimizing refuse-derived fuel production: a review of pre-treatment techniques for municipal solid waste reclamation

Addressing Soil Acidity Challenges: Promoting Tea Production as Alternative Crop in Ethiopia -- Review

The prevalence of acidic soils in Ethiopia presents a significant obstacle to improving agricultural productivity and restricts the implementation of sustainable farming practices that could enhance food security. Acidic soils are typically defined by their high concentration of hydrogen ions and a lack of essential nutrients, which collectively create an environment that is less conducive to the growth of many vital staple crops. Consequently, farmers faced with these conditions often struggle to achieve optimal yields, which exacerbates food scarcity and undermines economic stability. To effectively combat the issues posed by acidic soils, it is imperative to adopt targeted soil management strategies that are specifically designed to address these challenges. This may include the implementation of soil reclamation techniques that aim to neutralize soil acidity and restore nutrient balance. Additionally, comprehensive initiatives must be undertaken to promote agricultural resilience, which could involve the cultivation of alternative crops that are better suited to thrive in acidic conditions, such as tea. This paper aims to provide a thorough examination of several key aspects related to the development and management of acidic soils in Ethiopia. It will investigate into the processes that contribute to the formation of acid soils, as well as the various types of acid soil present in the country, explore the distribution of acidic soils throughout Ethiopia, highlighting areas that are particularly affected and the implications for local farming practices. Furthermore, the analysis will address the specific impact of soil acidity on crop growth, yield, and quality. It will investigate how soil acidity influences the availability of essential nutrients for plants, thereby affecting the overall health and productivity of crops grown in these conditions. The promotion of tea production in Ethiopia is another critical topic that tea cultivation not only offers a viable alternative crop but also presents opportunities for economic development and diversification in agricultural systems. The mechanisms that confer aluminum resistance in tea plants will be discussed, as well as the ways in which aluminum can stimulate growth in these crops, thereby illustrating the unique resilience of tea plants in acidic environments. By addressing these complex issues holistically, the paper seeks to contribute valuable insights and foster a deeper understanding of how to navigate the challenges posed by acidic soils in the Ethiopian agricultural landscape.

Soil organic carbon and nitrogen in a carboniferous spoil heap as a function of vegetation type and reclamation treatment

AbstractEvaluating the impact of vegetation types and reclamation methods on soil organic carbon and nitrogen in carboniferous spoil heaps is critical for selecting the best vegetation type and reclamation method to improve ecosystem services in a changing climate. This paper presents the relationship between vegetation types (woodland, forbland, and grassland) and reclamation techniques (barren rock, topsoil application, succession, and cultivation) on soil organic carbon (SOC) and total nitrogen (TN) in developing soils on carboniferous rocks in coal mine heaps. Soil samples were collected from the litter layer (Oi + Oe) and the A horizons (0–10 cm). The results revealed that vegetation types and reclamation methods significantly affected SOC and TN stocks. Woodland exhibited higher SOC and TN in the Oi + Oe horizons than other vegetation types. Topsoil application and cultivation resulted in the highest SOC and TN stocks in the A horizons (0–10 cm) under woodland and forbland compared to succession on bare carboniferous rock. In grassland, there was no significant difference in SOC stock under topsoil application and cultivation; however, significantly higher TN stock was observed in the 0–10 cm areas with topsoil application compared to succession on bare carboniferous rock. Based on the results, topsoil application is recommended to improve SOC if the mining site is restored using woodland. Conversely, grassland exhibits a similar amount of SOC stock with or without topsoil application. Considering the difficulty of obtaining topsoil, we suggest that grasses are optimal for SOC stock in the studied mining sites, followed by forbs.

Can Geopolymer Be a Replacement for Portland Cement in Full-Depth Reclamation Projects? Short- and Long-Term Performance Analysis

The fundamental concern of the full-depth reclamation (FDR) technique using Portland cement (FDR-PC) lies in its detrimental effect on the environment. Therefore, researchers are exploring alternative binders that are comparatively greener but compatible with FDR. This study evaluates both the strength and durability aspects of FDR incorporating geopolymer binder (FDR-GP) as an alternative to conventional FDR-PC. Various blends of fly ash (FA) and ground granulated blast furnace slag (GGBS) have been experimented with as geopolymer pre-cursors, ensuring that the additive content does not exceed 20% by weight of the total mix. Sodium hydroxide (NaOH) was utilized for the alkalinization in varying molarities to enhance the performance of the mixes. The experimental design was formulated to achieve a target 7-day unconfined compressive strength (UCS) strength of 4.95 MPa. This was obtained at a lower molarity (M) of 2 M and a 70% FA, 30% GGBS binder content. The mixes performed satisfactorily in both compression and flexure, along with excellent durability properties analyzed through wetting and drying tests. Furthermore, the long-term performance of FDR-GP mixes was investigated with regard to both UCS and flexural strength after 56, 161, and 238 days of curing. Thereafter, a comprehensive microstructural analysis was conducted to understand the fundamental changes in the matrix that influence mix performance. The outcome of this research confirms the potential of using FA/GGBS-based geopolymer as an alternative binder in FDR projects of flexible pavement, the mechanical and durability properties of which adequately satisfy the requirements as stipulated in various design standards.

Influence of reclamation techniques and vegetation types on water retention in hard coal spoil heaps

AbstractThis study examines the relationship between the reclamation method (with topsoil and with bare rock), individual species, and land cover (woodland, grassland, and forbsland) on micro‐climate and retention properties, that is, volumetric water content (vwc) and water storage capacity (S). The large overburden dump “Sośnica” in Upper Silesia served as a research site, which makes it possible to investigate the planned experimental variants with relatively homogeneous properties of the deposited rock. The study uses statistical analysis and multilinear regressions to investigate the correlation between reclamation method, species, and land cover with parameters such as atmospheric temperature, relative humidity, vwc, soil temperature (st), and S. The experiments were carried out both in the field and in the laboratory. The results of this study indicate that the parameters related to retention properties were higher in the recultivated areas than in the areas left to natural succession. “S” was significantly higher in grassland and forbsland (15.67–16.52%) than in control plots where 10.23% was found, and in areas where an additional soil layer was applied (14.72%). Maximum vwc (22.17%) was on plots with topsoil than on bare rock (14.89%). Vwc were highest in the areas designated as grassland (28.54%), in comparison with woodlands and forblands (the control without vegetation cover had the worst thermal and retention properties). This study sheds light on the effects of reclamation method, species, and land cover on various parameters and helps to understand the importance of appropriate reclamation techniques for soil and water conservation. Further research on the impacts of reclamation techniques and land cover on micro‐climatic conditions in diverse post‐mining landscapes is crucial for developing globally applicable restoration strategies that promote ecological resilience.

Spatial analysis and mapping of intensity and types of agricultural salt-affected soils around Abaya and Chamo Lakes, South Ethiopia Rift Valley

PurposeSalt-affected soils have significant enough salt concentrations to impact other land and soil resource uses, plant health, soil characteristics, and water quality. Consequently, a study was carried out in the South Ethiopian Rift Valley area around the lakes of Abaya and Chamo to determine the intensity and the types of salt-affected soil and map their spatial distributions. MethodsAt 0–20 cm depths, a grid soil sampling scheme was employed to gather data from agricultural soils affected by salt. An adequately spaced grid cell of 200 m*200 m or seven transects, with seven samples collected every 200 m on each sampling site, was generated by the QGIS software's Fishnet tool, and an auger collected 226 soil samples from the proposed 245 soil sampling points. The analysis and interpretation of the data were done using both statistical and geostatistical methods. The un-sampled surface was predicted and mapped from laboratory point data using the standard Kriging algorithm in QGIS. ResultsAccording to the results, the soil in the study area was rated as strongly alkaline and moderately alkaline in the reaction. The coefficient of variation (CV) was the lowest for soil pH. Except for the Ganta Kanchama site, low CV (<10 %) confirmed the similarity of pH values throughout all research areas. The EC values depicted that the study area is slightly saline except for the Ganta Kanchame site, which rated moderately saline to strongly saline. The variability of soil EC rated moderate to strong variation for the studied area. The exchangeable sodium percentage (ESP) values distribution between the study sites demonstrates considerable variability and difference. The area is dominated by low to high-risk rate soil sodicity, as evidenced by the soil ESP CV of the studied area, which was >100 % and showed significant variability among the samples. Out of 2274.65ha of the studied area, the type of salt 62.28 %, 26.09 %, 10.99 %, and 0.63 % were categorized as non-saline non-sodic, saline-sodic, sodic, and saline, respectively. Following saline-sodic, sodic, and saline soils, respectively, non-saline and non-sodic soils comprise most of the investigated areas. ConclusionsThe result indicates almost all the salt-affected areas were situated in relatively lower slope areas exhibiting a flat to almost flat slope (0–2%). The study's findings are that the studied area needs specific soil management strategies to boost the salinity and sodicity problems around the study area and recommended reclamation techniques as the extent of the problems.

An experimental investigation and predictive modeling using machine learning technique for reclamation of metal values from scrap NdFeB magnets

Neodymium-Iron-Boron (NdFeB) magnets are widely used in various industries due to their exceptional magnetic properties, such as high coercivity, remanence, and maximum energy product. These magnets consist of rare earth elements (REEs) viz., neodymium (Nd), praseodymium (Pr), and Dysprosium (Dy), along with other metals. With the ever increasing demand for REEs and the need to bridge the supply gap, it is crucial to develop alternative methods for their extraction. Recycling metal from scrap magnets is a promising approach to address the pressure on the supply chain and work towards sustainable development. The primary goal of this study is to generate a predictive model based on machine learning to determine the optimal conditions for metal recovery from scrap NdFeB magnets through water leaching after chloridizing roasting. Bench-scale leaching experiments were carried out to generate a dataset for statistical process optimization and machine learning analysis. The leaching kinetics of neodymium was also explored, and mixed-controlled shrinking core model was found to be most suitable, with an activation energy of 58.11 kJ/mol in the temperature range of 25– 95 °C. This study is the first to utilize a machine learning approach to analyze the potential process variables and their impact on metal recovery from calcined NdFeB magnet powder. A comparative analysis between experimental and machine learning approaches is presented to predict the optimal conditions for selective recovery of metal values from scrap NdFeB magnets. The maximum efficiency of extraction of metal ions was found to occur at a temperature of 95 °C, solid to liquid ratio of 125 g/l, and leaching duration of 60 min.

A Calculation and Optimization Method for the Theoretical Reclamation Timing of Cropland

In mining areas with high groundwater tables, mining subsidence can lead to the inundation of cropland by water, causing damage to cropland and posing a threat to national food security. The implementation of concurrent mining and reclamation techniques can effectively enhance the reclamation rate of cropland. This technique requires engineers to initiate reclamation measures before cropland waterlogging occurs. Therefore, when mining a panel underground, an accurate calculation of the time when cropland becomes waterlogged, known as the theoretical reclamation timing, is crucial. To address this issue, this study proposes a computational method for the theoretical reclamation timing of cropland under the conditions of single-panel mining based on intelligent optimization algorithms. In addition, this paper also proposes an optimization method for the theoretical reclamation timing of cropland within a district based on an intelligent optimization algorithm. Utilizing this method makes optimizing the layout of multiple panels possible, thereby delaying the theoretical reclamation timing for cropland within a district. This approach aims to shorten the duration of reclamation projects and minimize their interference with agricultural activities. Through experimental validation, this paper demonstrates the reliability of these two methods. This study is beneficial for the rational planning of reclamation projects.

Electroneutralization desalination with spontaneous chemoelectric power generation

This study designs a novel electroneutralization desalination cell using reaction heat from acidic-alkaline wastewater neutralization to desalinate wastewater and generates chemoelectric power. Several key performance indicators are measured in terms of the energy, environmental and economic aspects of the system, including the ionic flux, the electrical energy produced, the electrical energy consumption for desalination, parasitic losses, overall energy conversion efficiency and desalination performance. The maximum peak power density is ∼31.5 mW/cm2 at 83.5 mA/cm2 and the desalination efficiency is 62 % using brine. The overall energy conversion efficiency is ∼81.8 % and the desalination followed the zero-order reaction. Assuming a 1.5 million litres per day treatment capacity integrated with reverse osmosis, the system has environmental and economic benefits, with 44.5 kg-CO₂eq greenhouse gas emissions per cubic meter of treated brine, and a discounted payback period of 4.2 years. This study demonstrates a pioneering electroneutralization technique for self-sufficient brine valorization and wastewater reclamation.

Full-Scale Evaluation of Airfield Pavement Runway Reconstruction with Full-Depth Reclamation Technique

Full-depth reclamation (FDR) has been identified as a strategic in-place recycling technique that is readily available for effecting a rapid restoration of the structural capacity of abandoned airfield pavements in contingency environments. A full-scale pavement section was designed to investigate the performance of pavement sections containing an FDR layer under simulated loading conditions of a tactical heavy aircraft. The FDR materials were composed of various combinations of base material types (i.e., gravel and limestone) and different asphalt layer thicknesses (i.e., 51 mm and 102 mm). The FDR blends were stabilized with a combination of 3% asphalt emulsion and 2% Portland cement. The FDR pavement section consisted of six different test items to investigate the performance of various FDR material types, asphalt layer thicknesses (i.e., 51 mm and 76 mm), and unpaved landing zones. The performance of the existing pavement and the FDR pavement test sections was compared to assess the improvements resulting from the rehabilitation of airfield pavements using the FDR technique. The results indicated that FDR was effective in restoring the structural condition of a damaged asphalt pavement section to support additional aircraft operations. The quality of the FDR blend had a significant impact on pavement performance, whereas the impact of the asphalt layer thickness was insignificant. Finally, the unpaved FDR sections also demonstrated enough structural competency to support a low volume of aircraft traffic before further surface layers are added during pavement reconstruction in contingency environments.

Chemical reclamation of waste green foundry sand and its application in core production

The disposal of Waste Foundry Sand (WFS) poses a significant challenge for the foundry industry today, primarily due to its composition of metal oxides (Al2O3, Fe2O3, MgO, CaO, and Na2O) and sand. These metal oxides, categorized as loosely and strongly bound clays, are considered impurities in core production. This study proposes a chemical reclamation technique for WFS using fresh acid solutions or acidic industrial effluent. Experiments were conducted to remove the loosely and strongly bound clays from the WFS, optimizing parameters such as acid concentration, sand to acid loading, temperature, stirring speed, and reaction time to achieve optimal performance. The quality of the reclaimed sand was evaluated using various foundry standard tests, including determination of clay contents, compressive strength, Grain Fineness Number (GFN), Loss on Ignition (LOI), Acid Demand Value (ADV), and scanning electron microscopy. The reclaimed sand exhibited a loosely bound clay content of 1.5 %, oolitic content of 5.5 %, a grain fineness number of 55, a loss on ignition of 1.92 %, and an acid demand value of 1.5 ml/100 g of sand. Field trials demonstrated that the reclaimed sand can be effectively used for core production at an economical rate.

Effects of Biochar and Municipal Solid Waste Compost on Soil Physical Quality and Productivity Index Under Sorghum Cultivation Irrigated with Saline Water

ABSTRACT Amending soil with different materials is gaining acceptance as an effective and inexpensive technique for reclamation of salt-affected soils. The main idea of this study was to investigate the effects of biochar, compost of municipal solid waste and different water salinities level on soil physical quality (SDexter) and soil productivity index (SPI). The treatments were as followed: Control: Soil without biochar or compost and irrigated with tap water, S1: Soil without biochar or compost and irrigated with saline water (EC = 4.5 dS m−1), S2: Soil without biochar or compost and irrigated with saline water (EC = 9 dS m−1), B: Soil amended with 1.5%w/w biochar and irrigated with tap water, B+S1: Soil amended with 1.5%w/w biochar and irrigated with saline water (EC = 4.5 dS m−1), B+S2: Soil amended with 1.5%w/w biochar and irrigated with saline water (EC = 9 dS m−1), C: Soil amended with 1.5%w/w compost and irrigated with tap water, C+S1: Soil amended with 1.5%w/w compost and irrigated with saline water (EC = 4.5 dS m−1), C+S2: Soil amended with 1.5%w/w compost and irrigated with saline water (EC = 9 dS m−1). Soil water characteristic curve (SWCC), Field capacity (FC), Plant wilting point (PWP), Plant available water (PAW), Dexter’s index of soil physical quality (SDexter) and SPI were examined in a greenhouse experiment. The SPI was calculated by integrating the effects of six soil quality indices: plant available water, organic matter (OM), Electrical conductivity (EC), pH, Bulk density (BD) and Root weighting factor (RF) for all treatments were calculated. The results showed that the B treatment had a slightly higher effect on SWCC. The applied B and C treatments caused insignificant increase in PAW relative to the control. In addition, application of biochar or compost to soil significantly increased the SDexter. The application of C treatment had insignificantly higher value of SDexter compared to other treatments. Compared with the control, SPI was significantly higher for the B and C treatments. Overall, the application of biochar/compost minimized the destructive effects of saline irrigation water and improved the quality of the salt-affected fine-textured soil.

Инновационные технологические решения инженерно-биологических сооружений на мелиоративных системах АПК

The purpose of the research is to prepare and recommend the implementation of a number of technical solutions for the construction of bioengineered systems for small irrigation systems of surface irrigation along furrows using new environmental techniques of land reclamation. Hydraulic elements and lands of reclamation systems, which are eroded for a number of reasons, must be reliably protected from erosion. As part of the project “Improving the methods of engineering and reclamation of small water bodies of the agro-industrial complex”, bioengineering systems and technologies for protecting not only the coastal areas of small rivers and ponds, under-river water intakes, but also the canals of small surface irrigation systems along furrows were developed and tested under natural conditions using new environmental protection techniques for land reclamation. Biopositive designs are made of local and environmentally friendly man-made materials. Mixed structures contain: gabion mattresses; geomats; metal gratings; geogrids filled with crushed stone; flexible pipelines and other natural and nature-like components. It is noted that the introduction and use of biopositive structures of the developed structures for supplying water for irrigation in reclamation systems of the foothill zones of the North Caucasus Federal District leads to an increase in the economic effect by approximately 2 times and a reduction in the cost of supplied water by more than 40%.

PERFORMANCE EVALUATION OF LATERITE AND PULVERIZED RECLAIMED ASPHALT PAVEMENT STABILIZED WITH BASE SEAL AND CEMENT

This research delves into the effectiveness of incorporating pulverized Reclaimed Asphalt Pavement (RAP), Base Seal, and cement to enhance the stability of lateritic base materials in Nigeria. Addressing a crucial gap in pavement engineering literature, particularly the underexplored use of base seals as liquid stabilizers, the study adopts a comprehensive methodology involving literature review, field evaluation, and laboratory tests. Analyzing various material mixes, from pure Laterite to combinations with RAP, Base Seal, and varying cement contents, the research reveals substantial improvements in crucial engineering properties. Enhanced particle size distribution, reduced clay content, and optimal compaction characteristics at 0% cement content for laterite materials with pulverized RAP signify the positive impact of these additives. California Bearing Ratio analysis establishes a consistent correlation between higher cement content and improved load-bearing capacity. Notably, the synergistic effects of RAP and base seal, particularly at 5% cement content, showcase the highest CBR value (91), indicating optimal conditions for strength and stability. The study concludes with practical recommendations for road maintenance authorities, advocating for innovative approaches like full-depth reclamation techniques and stabilized full-depth reclamation, exploring different RAP to base material ratios, examining curing periods' impact, assessing long-term performance, considering environmental implications, and conducting field trials for validation. Overall, these findings contribute valuable insights to pavement design practices, fostering the development of resilient infrastructure in construction projects.

Управление устойчивостью аграрного землепользования на локальном уровне с использованием ГИС-технологий и специального картографического материала

The purpose of the study: analysis of geoecological factors and conditions affecting the sustainability of agricultural land use in the forest-steppe zone of the Altai Krai and its assessment. Research methods: The main scientific method of this study was system analysis, which was used to study the agricultural landscape management system. Methods of analysis and synthesis were used to identify structural units of land management, structuring the land information system (LIS) and special cartographic material, as well as studying the structure of agricultural landscapes. We also used the cartographic method in the design of unique map diagrams and information analysis in modeling agricultural land use. Research results. Based on the results of a long-term assessment of the sustainability of three agricultural land uses located in different natural and climatic zones, the conditions and factors that form the basis of the agricultural land use management system using GIS technologies were established. We found out that in order to manage the sustainability of agricultural landscapes, the mandatory information layers included in the data bank of a geographic information system (land information system) must include the following special cartographic materials: maps (scale 1:10000 or 1:25000) – landscape, soil, slope steepness, erosion, types of areas, tracts, lands, as well as the geomorphological profile of the surface. By processing materials with an information system, it is possible to implement at least 10 models for managing the sustainability of agricultural land use, which involve varying the structure of lands, lands, crop rotations, a set of crops, farming systems, a list of agro-, phyto-, reclamation techniques and measures aimed at achieving ecological and economic balance and, as a consequence, the efficiency of use of land resources. Conclusions. 1. Based on long-term spatio-temporal studies of agricultural landscapes of agricultural enterprises, a mandatory set of special cartographic materials of the geographic information system data bank has been determined, aimed at managing the sustainability of agricultural land use. 2. Using unique cartographic materials as an example, the possibility of modeling management scenarios in different natural conditions, characterized by different stability and efficiency, is shown. Modeling of agricultural land use makes it possible to determine capital investments and economic costs (economic and agronomic sustainability) when implementing the selected model, created on the basis of an analysis of the limiting factors of the territory. 3. The results of scientific research can be used in managing the sustainability of agricultural land use at the level of a municipal district and agricultural organization.

Dissemination of the Agroecological Model of Alang-Alang Land Reclamation to Increase Land Productivity

Using reed land for agriculture and improving productivity is cheaper than clearing forests because clearing new forests negatively impacts environmental quality. Reed control technology combined with an agroecology approach is expected to ensure a sustainable eradication of reed populations followed by technical culture and food crop cultivation patterns throughout the year. This community service program can solve food production problems, land fertility, and other environmental impacts. Community service program solutions can classify reed land based on land quality, educate the community in utilizing reed land reclamation techniques in ready-to-plant land blocks, evaluate the skills of farmers/communities based on crop production in reed reclamation blocks, and involve the community in naming superior and environmentally friendly agricultural varieties in the la block program solutions can classify reed land based on land quality, and educate the community in utilizing reed land reclamation techniques in ready-to-plant land blocks, evaluate farmer/community skills based on crop production in reed reclamation blocks, and involve the community in naming superior and environmentally friendly agricultural varieties in reed reclamation blocks.

Influence of agromelioration and drainage methods on the field crops productivity

The effectiveness of ameliorative strip loosening to a depth of 50-60 cm and volumetric soil slotting to 45-50 cm, their influence on the productivity of field crops and agrophysical properties of drained soils with different ameliorative systems (interdrainage distance of 18 and 28 m) was studied. The experiment was carried out in the period 2015-2021. at the Gubino agricultural polygon of the All-Russian Research Institute of Reclaimed Lands (Tver Region). The soil is soddy-podzolic cultivated light loamy gleyic, drained by closed pottery drainage, formed on a moraine. Volumetric slotting was carried out with a specially designed tool with filling the subarable part of the slot with crushed straw and plant residues mixed with a humus layer. Ameliorative loosening (MR) was carried out with a converted chisel plow. The pitch of slotting and MP is 140 cm. According to the generalized data, the best results on both drainage systems were obtained in the variant with volume slotting. Ameliorative loosening increased the yield of grain crops, on average over 5 years, by 0.60 t/ha (17.0%) and 0.79 t/ha (20.7%), slotting by 0.90 and 1.02 t/ha ha (25.6 and 26.7%), respectively. Additional grain harvest for the five-year period of MR action on the estimated drainage was 3.0, on sparse - 3.95 t/ha, and with volumetric slotting of the soil - 4.5 and 5.1 t/ha, respectively. On spring rapeseed, the best results were also obtained in the variant with sparse drainage and volumetric slotting of the soil. The increase in the yield of green mass in this variant, on average over 3 years, amounted to 3.6 t/ha of green mass, or 19.0%. It has been established that on soddy-podzolic light loamy gleyic soils with an atmospheric type of water supply, when designing ameliorative systems for field crop rotations, it is possible to use drainage systems with extended, compared to the calculated, interdrainage distances, which helps to reduce the cost of drainage. The use of land reclamation techniques increases the efficiency of sparse drainage.

ON THE NEED FOR A COMPREHENSIVE GEOECOLOGICAL ASSESSMENT OF LANDS DISTURBED BY MINING

Link for citation: Gavrilov V.L., Nemova N.A., Reznik A.V., Kosarev N.S., Kolesnikov A.A. On the need for a comprehensive geoecological assessment of lands disturbed by mining. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 10, рр. 76-87. In Rus. The relevance of the study is caused by the need to systematize information on the methods and procedure for obtaining data for a comprehensive geoecological assessment of territories disturbed by mining, based on the initial state of natural and modified components of the environment with the processes and phenomena occurring in it. This enables us to obtain information about the territories required for the development of methods and techniques for the subsequent reclamation of lands disturbed by mining. Objective: using various methods and techniques, to analyze methodological approaches that allow generating the necessary and sufficient volume of primary and required information synthesized on its basis, to proceed from a general to a comprehensive and detailed geoecological assessment of territories and areas disturbed and/or planned to be disturbed by mining operations. Objects: territories of Russia in mining regions disturbed by mining operations. Methods. Pre-selection of materials published in various publications since 2000 was carried out. Russian (E-library, VINITI RAS) and international (Scopus, GeoRef) information systems, websites of specialized and general scientific journals, library collections, and authors’ materials were used. When querying, the following basic terms and phrases were used in various combinations: «geoecological assessment», «assessment methods», «territories disturbed by mining», «remote sensing», «environmental condition». Of more than 1000 pre-identified publications, mostly Russian, devoted to various aspects of collecting and obtaining information on assessing the environmental condition in mining areas, more than 150 were selected. Publications were analyzed taking into account the most complete representation by region and publication. Additionally, materials published by federal and regional management and control authorities were used. The most important and representative ones were included in the review. Results. Existing and promising methods for collecting various data used in the geoecological assessment of territories disturbed by mining are considered. If required, these data will be further processed. Environmental, economic and social problems caused by the influence of mining operations are identified, the solution of these problems requires the generation of various information. The role of reliable and representative primary data measured on various scales is formulated to make a correct assessment of their impact on basic environmental components. The influence of the conditions of mining coal and ore deposits on environmental situation of the territories is considered. The necessity of using a set of methods for collecting and processing information, selected with regard to peculiarities of each mining area and mining specifics of various mineral deposits, is shown.

Integrated Mining and Reclamation Practices Enhance Sustainable Land Use: A Case Study in Huainan Coalfield, China

In the coal-grain composite area (CGCA) of eastern China with a high groundwater table (HGT), underground coal mining subsidence has caused extensive submergence of farmland, posing a significant threat to regional food security. Currently, land reclamation techniques in mining subsidence areas primarily focus on post-mining reclamation (PMR) of stable subsidence land with a low reclamation rate. This study investigated the application of concurrent mining and reclamation (CMR) technology for unstable subsidence land in a representative HGT mining area, namely the Guqiao Coal Mine in the Huainan Coalfield. Firstly, mining subsidence prediction and geographic information technology were employed to simulate the spatio-temporal evolution of dynamic mining subsidence, taking into consideration the mining plan. Subsequently, phased reclamation parameters were quantitatively designed by integrating the dynamic mining subsidence and surface reclamation measures. Lastly, scenario simulations were conducted to discuss the effectiveness of CMR in comparison with non-reclamation (NR) and PMR. Additionally, reclamation and ecological restoration strategies for coal mining subsidence areas with comprehensive governance modes were proposed. The findings indicated that mining activities have led to a reduction in both the quantity and quality of original farmland, with 70% of the farmland submerged and rendered uncultivable. In contrast to PMR, which achieved a reclamation rate of 29%, CMR can significantly increase the farmland reclamation rate to 69% while also prolonging the service life of farmland. This study provides theoretical support and technical references for promoting sustainable mining practices, protecting farmland, and facilitating the high-quality development of coal resource-based cities.