Plant variation phenomenon

Due to geochemical anomalies in metallogenic areas, plants or plant communities often cause ecological variation, mainly as follows: ① special plant species and genera appear. Mineralization causes the enrichment of some elements in some areas, and some so-called indicator plants appear, such as "copper grass" in some copper mining areas in the middle and lower reaches of the Yangtze River in China. In some copper-rich soil areas, Korean pine develops well, while other plants die. When the soil is rich in zinc, leafy plants like wormwood will flourish, while other plants rarely grow. (3) The plant growth density is abnormal, and some elements can make some plants grow abnormally; On the other hand, some elements in ore-bearing areas can also poison plants, causing plants to wither or die, resulting in "gaps" or "bald spots". Such as sulfide deposits, radioactive element deposits and areas with high chromium and nickel content, are toxic to plants. The spontaneous combustion of coal mines leads to high temperature and withers the surface plants. For example, in Yakutia, Soviet Union, there are particularly lush and unusually tall alders and larches on the kimberlite cone containing diamonds, which has become a symbol for identifying kimberlite cones. ③ Plant ecological abnormality. After all, the first two phenomena are relatively rare. In most cases, they often cause ecological variation and differences in spectral response of vegetation, which are shown in remote sensing images. Yost and Windros have measured the reflectivity of Picea koraiensis and Abies koraiensis growing on normal soil in ore bodies (copper-molybdenum belts) and non-mineralized areas (Figure 9-3). Their spectral curves are obviously different, especially in the near infrared region. Remote sensing data can quickly delineate the distribution of plant anomalies and can be used to indicate prospecting. For example, Venezuela used aerial remote sensing data to analyze the distribution characteristics of plants on the ground, thus finding an iron mine with a reserve of 500 million tons.