A Spanish-American team applied the analysis of satellite images to study areas exploited for charcoal. The study, published in the journal Remote Sensing of Environment, has focused on mining regions of El Bierzo, Kentucky (USA) and Australian region.
Get information on the location of mining activities is essential to know how to evolve environmentally and restoration activities that can be carried out after logging. Advances in the analysis of satellite images offer new possibilities in this line, but so far there has been no study to analyze the changes produced by open pit mining on a global scale. But Spanish-American team of scientists proposed a new technique.
Researchers at the University of León, Valladolid University and the University of California (USA) have applied a novel approach to the analysis of satellite images to study areas operated by coal. Specifically, the paper examines three coal mining areas in the world: El Bierzo in the province of León, Kentucky in the U.S. and Australian region. The results are published in the journal Remote Sensing of Environment.
As detailed by Alfonso Fernández-Manso, Department of Agricultural Sciences and Engineering, University of León on the campus of Ponferrada, spent several years working on this line “given the proximity of the mining issue in the province of León”, but also working Carmen Quintano researcher of the University Institute of Sustainable Forest Management Research Campus of Palencia.
“We started developing a survey methodology itself but note that in the U.S. was used, although in non-mining applications, a more advanced technique. We saw the possibility that this method is applicable to the work being done here and other parts of the world and contacted Dar Roberts, University of California, one of the world’s best scientists in the field of remote sensing,” says the researcher. Thus began a joint effort that has included a six-month stay at the University of California.
As recalled Fernandez-Manso, coal “is of paramount importance in the production of energy on the planet and is linked to many environmental problems.” In this sense, most of the coal is mined open pit which produces “an immense number of spots that can be seen from satellites.” The idea was to find a scientific method to estimate what areas are currently being exploited on the planet, because “if we can get good maps do know how to move these farms and what impact they can have on climate change or energy production”.
The method, called MESMA (Multiple End Member Spectral Mixture Analysis) allows “studying the spectra of different soils where it is working, how to behave and to build models that allow us to differentiate areas of coal exploited by unexploited and quantify its surface “through Landsat imagery. Thus, these areas could be exploited to study at different times and see how they evolve.
Regarding the methods currently being used to accomplish this task, the researcher progresses, the work provides improvements of between 20 and 30% in the estimate, “important values”.
While the work is three-zone maps of the world, the aim would be to develop the mapping of all coal mines in the world open leveraging global coverage offering Landsat imagery, something “that does not exist.” In addition, the methodology would address other important issues related to this type of mining, as “knowing the total coal production or check in detail the environmental impact, if being restored or abandoned farms, from data provided by satellite images through this methodology.”
Mining activity in general and open-pit mining in particular can lead to serious environmental degradation. Soil erosion and increased sediment load as a result of the abandonment of the activity without subsequent restoration are some of the environmental implications generated great controversy worldwide. Currently, it is estimated that there are more than 6.185 million tons of coal worldwide with China, U.S., India, Australia and South Africa the main producing countries.