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Soil carbon sequestration is vital to reduce the atmospheric carbon concentration, which is expected to increase within future climatic scenarios. The present study aims to investigate the effects of land use changes to different plantation systems on SOC stocks, and simulate these changes using the RothC model in Mizoram, India. With this aim, four land uses, viz., secondary forest, oil palm, orange, and arecanut plantations, established on degraded shifting cultivation lands, and a control natural forest were selected for this study. The soils were sampled 0–30 cm in the secondary forest, plantations, and the natural forest, at an interval of five years. Measured SOC stocks were the highest in the secondary forest (67.0 Mg C ha−1) and the lowest under the oil palm plantation (37.4 Mg C ha−1), 10 years after land use conversion. The climate change projections for 2021–2035 and 2036–2050 indicated that temperature and rainfall changes, projected to increase by 0.8 and 2.0 °C, and 5.9 and 5.4%, respectively, will affect SOC stocks in the future differently, depending on the land use and carbon input from vegetation. Baseline climate simulations under land use change showed the highest increase in the SOC stock under the secondary forest (116%), and the lowest in the oil palm plantation (27%). Overall, the model predicted that SOC stocks would increase, but the rate of change (0.23–1.86 Mg C ha−1 yr−1) varied with different land uses, plant species, and land management practices. The model results indicated that restoring secondary forest following the abandonment of a shifting cultivation and orange plantations are the best options to improve SOC stocks within future climate change scenarios. Conversely, arecanut and oil palm need to be reduced because the SOC storage is lower. [ABSTRACT FROM AUTHOR]

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]

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The extraction of natural resources through mining activities has tremendously increased to maintain the trade‐off between demand and supply of energy resources. Surface mining activities lead to deforestation, displacement of topsoil and overburden rocks, and disposal of huge amounts of waste that depletes ecosystem services. We attempt to summarize the recent advance in the restoration of mine degraded lands and their role in the sustainable management of the post‐mining ecosystem. Selective plantation and application of various soil amendments along with the topsoil potentially enhance the recovery of mine degraded lands. Afforestation of mine degraded lands can generate economic, social, and environmental benefits to mining companies and the regional population. Outcomes of numerous studies have highlighted the need for the selective plantation that demonstrates characters like stress tolerance, climate resilience, and native to the local ecosystem. Besides, it is important to restore the ecosystem in such a way that it can deliver ecosystem services and match the objectives of international policies like the United Nations Sustainable Development Goals. [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]

A field study was carried out (IB-valley areas, Mahanadi Coalfields Limited) to assess the bioaccumulation of heavy metals in the tree species, changes in physicochemical and nutritional properties of mine soils, and bioavailability of metals. Only limited amount of topsoil was added in the plantation pits in the ratio of 1:4 (topsoil: weathered mine spoils), which significantly improved pH and fertility. Out of the six analysed metals, the highest concentration was found for Fe followed by Mn > Zn > Cu > Cd > Ni in mine soils. Metal accumulation and bioconcentration factor (BCF) for each metal were calculated for edible fruit (Mangifera indica,Anacardium occidentale,Psidium guajava,Artocarpus heterophyllusandSyzygium cumini) and timber trees (Acacia mangium,Eucalyptusspp.,Techtona grandisandGravellia robusta). Higher metal accumulations were observed in edible fruit trees than control plants growing in garden soil. Significant variations of metal accumulations were observed amongst timber tree species with higher BCF values. Present study suggested that in spite of addition of topsoil, no significant improvement was observed for the bioavailable metal concentration in the mine soils. Additional care should be undertaken, if edible fruit trees are considered for afforestation of coal mine spoils. [ABSTRACT FROM PUBLISHER]

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 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]