Ahirwal Jitendra, Maiti Subodh Kumar
Department of Environmental Science and Engineering, Center of Mining Environment, Indian Institute of Technology (Indian School of Mines), Dhanbad, 826004, India.
Department of Environmental Science and Engineering, Center of Mining Environment, Indian Institute of Technology (Indian School of Mines), Dhanbad, 826004, India.
J Environ Manage. 2017 Oct 1;201:369-377. doi: 10.1016/j.jenvman.2017.07.003. Epub 2017 Jul 8.
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 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 hayear. Total ecosystem C sequestered after 2-14 years of revegetation increased from 8 Mg C ha to 90 Mg C ha (30-333 Mg CO ha) with an average rate of 6.4 Mg C hayear. Above ground biomass contributes maximum C sequestrate (50%) in revegetated site. CO flux increased with age of revegetation and found 11, 33 and 42 Mg CO hayear 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.
在露天煤矿开采造成的退化土地上，将次生林作为采矿后的土地利用方式具有很高的研究价值，因为其具有固存大气碳（C）的潜力。本研究的目的是评估采矿后复垦土地的土壤质量改善情况以及碳固存潜力随时间的变化。因此，本研究在一个大型露天煤矿项目（印度贾坎德邦中央煤炭田有限公司）的复垦时间序列场地（年轻、中年和老年）中进行，并将结果与参考林地（娑罗双树森林）进行比较。根据土壤有机碳（SOC）的增加、有效氮（N）以及土壤CO通量随着植被恢复年限的变化来评估矿山土壤质量。植被恢复14年后，SOC和N浓度分别增加了三倍和五倍，并且与参考场地相当。SOC储量的增加估计为1.9 Mg C ha-1年。植被恢复2 - 14年后，固存的总生态系统碳从8 Mg C ha增加到90 Mg C ha（30 - 333 Mg CO2 ha），平均速率为6.4 Mg C ha-1年。在植被恢复的场地中，地上生物量贡献了最大的碳固存量（50%）。CO通量随着植被恢复年限的增加而增加，在年轻、中年和老年排土场中分别为11、33和42 Mg CO2 ha-1年。植被恢复场地的土壤呼吸受温度的影响大于土壤湿度。研究结果还表明，对于矿山退化场地的植被恢复，应优先选择如印度黄檀和腺叶异翅香等树木。
