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A field study was carried out to assess the impact of revegetation on Technosol quality in the post-mining sites (Central Coalfield Limited, India). The study evaluated community structure, biodiversity, Technosol quality, and carbon (C) dynamics in the post-mining ecosystem (PME). The multivariate statistical tool was used to identify the key soil properties, and soil quality was evaluated by using Technosol quality index (TQI). One unreclaimed site (0 years) and four chronosequences revegetated coal mine sites (3, 7, 10, and 15 years) were studied and compared with an undisturbed forest as a reference site. Plant biodiversity indices [Shannon index of diversity (2.42) and Pielou's evenness (0.97) and Patric richness (12)] were highest in 15-year-old revegetated sites. Soil physicochemical and biological properties were recovered with the revegetation age. Soil organic C (SOC) stock significantly increased from 0.75 Mg C ha -1 in 3 years to 7.60 Mg C ha -1 after 15 years of revegetation in top 15 cm of soils. Ecosystem C pool increased at a rate of 5.38 Mg C ha -1  year -1 . Soil CO 2 flux was significantly increased from 0.27 μmol CO 2  m -2  s -1 in unreclaimed sites to 3.19 μmol CO 2  m -2  s -1 in 15-year-old revegetated site. Principal component analysis (PCA) showed that dehydrogenase activity (DHA), available nitrogen (N), and silt content were the key soil parameters that were affected by reclamation. A 15-year-old Technosol had a greater TQI (0.78) compared to the control forest soils (0.64) that indicated the suitability of revegetation to recuperate soil quality in mining-degraded land and to increase C sequestration potential.

Anthropogenic activities substantially altered the ecosystem's functioning and most of them are directly or indirectly responsible for biodiversity loss, land degradation, and climate change. Therefore, maximizing the conservation of natural capital and restoring the potential of the natural ecosystems are essential to sustain life on this planet. Where most of the economic activities are coupled with environmental degradation, the reestablishment of ecosystem attributes is a vital part of global conservation strategies. Mining activities cause inevitable loss of ecological structure and functions, while restoration of mine degraded lands provides an opportunity to reinstate ecological integrity and to develop a self‐sustaining ecosystem. However, it cannot be possible without learning from our experience, scientific research, community participation, traditional knowledge, political support, and economic backup. Here, we summarize some of the field observations explicitly based on the restoration of coal mine degraded lands in India. Experiences based on the practical approaches of ecosystem restoration highlight the key role of physical aspects of restoration, selection of plant species for biological restoration, and its combined effect on generating socioeconomic and environmental benefits. We recommend the inclusion of a site‐specific restoration plan, native species for reforestation, and involvement of the local community in restoration programs. Moreover, they are essential to attain the United Nations‐Sustainable Development Goals (UN‐SDGs) particularly, reduce poverty and hunger, provide affordable and clean energy, mitigate climate change, and reestablish life on degraded lands. [ABSTRACT FROM AUTHOR]

Development of secondary forest as post-mining land use in the surface coal mining degraded sites is of high research interest due to its potential to sequester atmospheric carbon (C). The objectives of this study were to assess the improvement in mine soil quality and C sequestration potential of the post–mining reclaimed land with time. Hence, this study was conducted in reclaimed chronosequence sites (young, intermediate and old) of a large open cast coal project (Central Coal Fields Limited, Jharkhand, India) and results were compared to a reference forest site (Sal forest, Shorea robusta ). Mine soil quality was assessed in terms of accretion of soil organic carbon (SOC), available nitrogen (N) and soil CO 2 flux along with the age of revegetation. After 14 years of revegetation, SOC and N concentrations increased three and five-fold, respectively and found equivalent to the reference site. Accretion of SOC stock was estimated to be 1.9 Mg C ha −1 year −1 . Total ecosystem C sequestered after 2–14 years of revegetation increased from 8 Mg C ha −1 to 90 Mg C ha −1 (30–333 Mg CO 2 ha −1 ) with an average rate of 6.4 Mg C ha −1 year −1 . Above ground biomass contributes maximum C sequestrate (50%) in revegetated site. CO 2 flux increased with age of revegetation and found 11, 33 and 42 Mg CO 2 ha −1 year −1 in younger, intermediate and older dumps, respectively. Soil respiration in revegetated site is more influenced by the temperature than soil moisture. Results of the study also showed that trees like, Dalbergia sissoo and Heterophragma adenophyllum should be preferred for revegetation of mine degraded sites. [ABSTRACT FROM AUTHOR]

Coal mine degraded land looses large amounts of soil nutrients during surface mining. However, the magnitude of the change in soil properties can be offset with afforestation. A chronosequence study of 1 to 8 years old reclaimed mine soils (RMS) in Singareni Collieries Company Limited (SCCL), India was carried out to assess the development of soil properties and nutrients stocks. Samples from three depths (0–20, 20–40 and 40–60 cm) were collected at 8 different reclaimed sites afforested since 1 to 8 years and their soil organic carbon (SOC), available nitrogen (N) and phosphate (P) stocks were quantified and the vertical distribution of these elements was studied. With time, bulk density, fine earth fraction (< 2 mm), soil water holding capacity and nutrient content improved due to afforestation. The total stock ranged between 2020–45,400 kg C ha − 1 , 38–444 kg N ha − 1 and 0.50–7.14 kg P ha − 1 in 0–60 cm depth and was significantly different between the ages of afforestation and the reference forest sites. Among the different soil depths, the top layer (0–20 cm) exhibited more than half of the nutrient stocks. Changes in soil properties may be associated with the development of vegetation cover over time. After 8 years of afforestation SOC and N stocks recovered by 60% of those measured in reference forest sites. The findings of this chronosequence represent a significant recovery of nutrient stocks during the early phases of reclamation. [ABSTRACT FROM AUTHOR]

Open strip mining of coal results in loss of natural carbon (C) sink and increased emission of CO 2 into the atmosphere. A field study was carried out at five revegetated coal mine lands (7, 8, 9, 10 and 11 years) to assess the impact of the reclamation on soil properties, accretion of soil organic C (SOC) and nitrogen (N) stock, changes in ecosystem C pool and soil CO 2 flux. We estimated the presence of C in the tree biomass, soils, litter and microbial biomass to determine the total C sequestration potential of the post mining reclaimed land. To determine the C sequestration of the reclaimed ecosystem, soil CO 2 flux was measured along with the CO 2 sequestration. Reclaimed mine soil (RMS) fertility increased along the age of reclamation and decreases with the soil depths that may be attributed to the change in mine soils characteristics and plant growth. After 7 to 11 years of reclamation, SOC and N stocks increased two times. SOC sequestration (1.71 Mg C ha − 1 year − 1 ) and total ecosystem C pool (3.72 Mg C ha − 1 year − 1 ) increased with the age of reclamation (CO 2 equivalent: 13.63 Mg CO 2 ha − 1 year − 1 ). After 11 years of reclamation, soil CO 2 flux (2.36 ± 0.95 μmol m − 2 s − 1 ) was found four times higher than the natural forest soils ( Shorea robusta Gaertn. F). The study shows that reclaimed mine land can act as a source/sink of CO 2 in the terrestrial ecosystem and plays an important role to offset increased emission of CO 2 in the atmosphere. [ABSTRACT FROM AUTHOR]

Large scale surface coal mining activities resulted disturbance of the local ecosystem by creating different land uses that alter soil properties and hydrological balance of the mining area and surrounding environment. The present study aims to evaluate the changes in soil properties in mining affected lands (mine face topsoil, wasteland and agriculture land) and reclaimed mine soil (RMS), and to quantify the changes of the selected soil properties with respect to reference Sal forest ( Shorea robusta Gaertn. F.). Changes in soil properties were analyzed on a profile basis (0–20, 20–40 and 40–60 cm). The study indicates that soil pH, electrical conductivity, and bulk density were increased significantly, while a decrease in nutrient content (N, P, and K) was observed in the mining affected lands. The infiltration rate in RMS was found ten times lower than the Sal forest. In comparison to Sal forest, the cumulative infiltration rate declines 85%, 80% and 75%, in RMS, topsoil and agriculture soil, respectively. The overall findings of this study indicated that conversion of Sal forest into other land uses due to mining significantly reduced the nutrient contents and soil quality of the area. Reclamation of the mine degraded land in short duration does not restore the overall properties of the soils, particularly the infiltration rate, which has long term impacts on the surrounding ecosystem. [ABSTRACT FROM AUTHOR]

Ecological restoration is an important aspect to recover the ecosystem structures and functions of coal mines degraded land. In India restoration practices must emphasize on the multidimensional approach to restore the ecosystem, which is self-sustainable and capable to support environmental interactions and ecosystem changes. With the rapid expansion of population, utilization of the resources, like energy, land use and fresh water increased to match the demand and supply ratio. Since, coal is a valuable resource of energy, its extraction by surface mining causes ecosystem disturbance. At the same time, it is mandatory to manage our restoration efforts to achieve economics of the time, energy and cost. This paper introduced the importance, theoretical and practical progress, and discussed some key problems for research in the future of ecological restoration of surface coal mines in India. [ABSTRACT FROM AUTHOR]

Surface coal mining activities have numerous consequences on terrestrial ecosystems. Loss of soil and biomass carbon pool due to mining activities is a serious concern in the rapidly changing environment. We investigated the effect of fast-growing trees (Albizia lebbeck, Albizia procera, and Dalbergia sissoo) on soil fertility and ecosystem carbon pool after eight years of afforestation in the post-mining land of Jharia coalfield, India, and compared with the adjacent natural forest site. Significant differences in soil organic carbon (SOC) and total nitrogen (TN) stocks in afforested mine soil and natural forest soils were observed. Greater SOC stock was found under D. sissoo (30.17 Mg·C·ha−1) while total N stock was highest under A. lebbeck (4.16 Mg·N·ha−1) plantation. Plant biomass accumulated 85% of the natural forest carbon pool after eight years of afforestation. The study concluded that planting fast-growing trees in post-mining lands could produce a promising effect on mine soil fertility and greater carbon storage in a short period. [ABSTRACT FROM AUTHOR]

Surface coal mining inevitably deforests the land, reduces carbon (C) pool and generates different land covers. To re-establish the ecosystem C pool, post-mining lands are often afforested with fast-growing trees. A field study was conducted in the 5-year-old unreclaimed dump and reclaimed coal mine dump to assess the changes in soil CO2 flux and compared with the reference forest site. Changes in soil organic carbon (SOC) and total nitrogen stocks were estimated in post-mining land. Soil CO2 flux was measured using close dynamic chamber method, and the influence of environmental variables on soil CO2 flux was determined. Woody biomass C and SOC stocks of the reference forest site were threefold higher than that of 5-year-old reclaimed site. The mean soil CO2 flux was highest in 5-year-old reclaimed dump (2.37 μmol CO2 m−2 s−1) and lowest in unreclaimed dump (0.21 μmol CO2 m−2 s−1). Soil CO2 flux was highly influenced by environmental variables, where soil temperature positively influenced the soil CO2 flux, while soil moisture, relative humidity and surface CO2 concentration negatively influenced the soil CO2 flux. Change in soil CO2 flux under different land cover depends on plant and soil characteristics and environmental variables. The study concluded that assessment of soil CO2 flux in post-mining land is important to estimate the potential of afforestation to combat increased emission of soil CO2 at regional and global scale. [ABSTRACT FROM AUTHOR]