Studies On The Soil Series Database And Its Preliminary Application In Zhejiang Province

Soil is the product of the interaction between various spheres in the earth. Soil has the effect ofexchanging material and energy in various spheres, and is the basis of terrestrial ecosystems. With thewidespread adoption of geographical information system(GIS) and the growing demand for scientificmanagement and rational use of land resources, the soil information system has emerged. As animportant part of soil information system, the soil series database has gained more and more attention.In China Soil Taxonomy, the soil series are the most primary units of the soil classification system, andhave the characteristics of classification of classifying soils based on quantitative features and provide adirect connection between soil classification and agricultural production in practice. Therefore, thestudies of soil series have much theoretical and practical significance. The establishment of soil seriesdatabases has become the important part of national soil science research.While national soil survey has been carried out, it has great significance to conduct research of soildatabase in Zhejiang Province. The study is supported by the special program for foundation research ofnational science and technology,“Soil Series Survey in China and complication of Soil Series inChina”(Grant No.2008FY110600) and has established a database of soil series with scale of1:250000.The study has used the soil survey results and conducted case study research in area of Zhejiang, hasinvestigated the soil carbon pool in Zhejiang Province. The results indicate that the total amount of soilorganic carbon(SOC) in Zhejiang Province is between about0.81and0.83Pg and the average soilcarbon density is between8.08and8.37kg�'m-2.The SOC density of different soil types varysignificantly in Zhejiang Province; In terms of the SOC density distribution, the SOC density in thesoutheast strip form into the low center, and increased gradually outward the north, west, south.According to the second general soil survey data in1979and the soil series survey in2009, with thegeographic information system (GIS) method, the temporal and spatial variations of SOC detail inZhejiang Province in the last30years have been investigated. The results indicate that SOC densitypresent a steady tendency on the whole, but there are a few soil types show a significant trend ofincrease or decrease. From the perspective of space, the SOC density decline significantly in thesouthern region of the Zhejiang Province with a drop of10kg�'m-2. The average organic carbondensity in paddies has increased, showing a very well carbon decline effect. The total amount of organiccarbon generally has not changed, but the percentage of main sub-categories SOC reserved present anaverage upward tendency.