Study On A Layer Chromaticity Characteristics And Chromogenic Substances Of Mountain Red Soil In Western Yunnan-Guizhou Plateau

In the soil,the most intuitive change is the soil chromaticity,which can reflect the information of the soil material composition,and the analysis of the material composition can determine the soil deposition environment and material source and reflect the climate and environmental changes.In the west of the Yunnan-Guizhou Plateau,a wide range of mountain red soil is distributed,which provides an ideal place for researchers of mountain red soil.This article selects the western part of the YunnanGuizhou Plateau as the research object,and uses the CIELAB color system to discuss its chromaticity characteristics and chromogenic substances.The CR-10 chromaticity measurement method,the shock sedimentation method,the CBD iron removal method,the heavy liquid method and the diffractometer identification method revealed the original sample of the original red soil,iron oxides,clay materials and detrital materials of the three soil-forming parent materials.According to the comparison of the chromaticity parameters,organic matter content,and chromogenic components of the mountain red soil,the typical mountain red soil chromochromic substances in the region are initially revealed.Change lays the foundation.The following conclusions are obtained by analyzing the color characteristics of Yamahara red soil and the typical chromogenic materials of Yamahara red soil:(1)According to the research,it is concluded that the coloring substances of the red soil in the west of the Yunnan-Guizhou Plateau mainly include iron oxides,clay substances,detrital substances,and organic matter.(2)The identification of iron oxide components in mountain red soils developed by carbonate rocks is mainly maghemite,hematite and goethite;the main minerals of iron oxides in mountain raw red soils developed by basalt are maghemite and hematite,Goethite,also contains a small amount of magnetite;iron oxides in the mountainous red soil developed by mud shale are mainly maghemite,hematite,goethite.(3)The montmorillonite and gibbsite clay materials developed in carbonate rocks are mainly montmorillonite and gibbsite;the montmorillonite and kaolinite clay materials developed in basalt are mainly montmorillonite and kaolinite;the montmorillonite clay materials developed in mud shale are mainly Montmorillonite,gibbsite and kaolinite.The identification of the detrital material composition of the three types of bedrock-developed mountain red soil is relatively simple.All the detrital materials are mainly quartz,and their semi-quantitative detrital material content is relatively high,while the basalt detrital material also contains a small amount of albite.(4)The average content of organic matter in the mountain red soil developed in carbonate rocks is 1.87%.The average value of organic matter content in the basaltdeveloped mountain red soil is 1.14%.The average content of organic matter in the red soil developed in the shale is 1.29%.(5)The brightness L* value of the mountain red soil,the average value of carbonate rock is 36.52,the value of basalt is 37.89,the value of mud shale is 46.61;the value of the redness of mountain soil red soil a*,the average value of carbonate rock is 19.51,The basalt is 19.07 and the shale is 19.22;the mountain red soil yellowness b* value,the average value of carbonate rock is 27.17,the basalt is 27.02,the mud shale is 31.14;the mountain red soil color C* value,The average value of carbonate rock is 33.48,that of basalt is 33.21,and that of shale is 36.70;the h* value of the mountain red soil,the average value of carbonate is 54.43,that of basalt is 55.25,and that of mud shale is 58.5.(6)Comparing the chromaticity parameters of iron oxides,clay materials and detrital materials,and the original soil,it is found that the brightness L* value of the original carbonate rock red soil is similar to the hematite L* value;the redness a* value Similar to a* value of maghemite;b* value of yellowness is similar to b* value of maghemite;C* value of chroma is similar to C* value of maghemite;h* value of hue is similar to magnetic red The a* values of iron ore are similar.The brightness L* value of the original red soil in typical basalt mountains is similar to the L* value of maghemite;the redness a* value is similar to the hematite a* value;the yellowness b* value is similar to the b* value of maghemite;The chroma C* value is similar to that of maghemite;the h* value of hue is similar to a* value of maghemite.The brightness L* value of the original red soil of typical shale mountains is similar to that of goethite;the redness a* value is similar to that of goethite;the yellowness b* value is similar to that of hematite b*;The chroma C* value is similar to that of maghemite;the h* value of hue is similar to a* value of hematite.