THE INFLUENCE OF ENVIRONMENTAL FACTORS ON ASPERGILLUS NIGER GRANITE WEATHERING

In order to explore the effects and influence of environmental factors on microbial restoration of waste rock, an efficient rock-weathering strain Aspergillus niger XF-1 was isolated from a granite face. Concentrations of SiO2 in nutrient solution at different temperatures, pH values, generation cycles, and vaccination quantities were measured using shake flask leaching and inductively coupled plasma optical emission spectrometer (ICP-OES) to analyze the grey correlation degree of weathering. The results reveal that the A. niger XF-1 strain can be used as a good fungal source for the restoration of degraded habitats in abandoned granite areas, and can also be used to promote the release of more Si elements in granite. Moreover, pH is the dominant factor affecting the weathering of granite by A. niger, followed by vaccination quantity and temperature, while generation cycle is the least important factor. The optimum temperature at which granite is weathered by A. niger was 28 degrees C, the most appropriate pH value was 3, the most suitable generation was the fifth, and the optimum vaccination quantity was 10(7) (spore numbers mL(-1)).