Study On The Properties Of The Representitive Soil Based On Regional Natural Factors In Qianzhong Plateau And Taxonomic Classification

Guiyang is the largest karst district in the southwest of China. In the last 60 s, soil researchers made a great investigation in the soil development and made a brand new set of soil classification system. As for now, it is not enough data on soil layer, soil depth,soil density on different slopes of hill,different grades of hills. On the other hand, it is made a lot harder to communicate with other countries with the beginning of standard, quantitative and international pedology of China and the world. It is necessary to join the soil taxonomy making the sustainable of soil management in Guizhou province. But the research basic is so weak that requests more statistic data on soil material and soil terrain.So, with the help of analyzing and background investigation, our research will focus on several representative regions in Qianzhong Plateau of Guizhou province. We will make a full description on soil material, slope and grades of different soil profiles and chemical analysis as the request in “China Soil Classification”. Our research shows below.1) The different types of soil material make the fundamental difference of chemical properties in the representativesoil profiles.The soil colors mostly are yellow-orange, black brown or dark grayish brown with the material of carbonatite rock. Its soil p H, organic matter or CEC is much higher than any other materials. The soil colors mostly are reddish brown and red brown with the material of sandshale. Its soil present acid and organic matter or CEC is a little lower than the carbonatite rock. The soil color reddish brown and its pH shows neutral or weak acid with the material of purple sandshale. Its organic matter or CEC is the lowest.2) Terrain factors make influence of soil with water distribution and material composition. The lower grades make soil better formation mostly in the foot of the mountain. The higher grades make soil worse formation mostly in the middle of the mountain. And for the top of the mountain,the soil nutrition is so weak that the organic matter or CEC is the lowest. However, the data show much higer in organic matter and CEC in shady slope than the sunny slope.3) According to the Keys to Chinese Soil Taxonomy(3rd vision), 5 diagnostic horizons and 8 diagnostic characteristics of the soils were characterized. The diagnostic horizons were mollic epipedon, umbric epipedon, cambic horizon, LAC-ferric horizon and argic horizon. The diagnostic characteristics were L.C. of carbonate rocks, L.C. of purplish sandstones, soil moisture regimes, soil temperature regimes, humic property, alic property, alic evidence, and ferric property.4) According to the Keys to Chinese Soil Taxonomy(3rd vision), including 4 orders(Ferrosols, Argosols, Cambosols, Primosols), 4suborders, 8 groups and 13 subgroups.