He Certification And Quality Evaluation Of Partly Soil Series Were Studied In Xianning City

Systematically understanding and classifying soil are the basis of the soil resource management. The current international trend of development of soil classification is quantitative, standardized classification of the soil. In this context, the mid-eighties of soil scientist in China actively carried out the research of Chinese soil taxonomic classification based on quantification of the level of development of modern soil science. Chinese soil classification system reforms the original idea of using Bio-climatic conditions as the basis, specific indexes and boundaries are not clear geographical classification, there are strict limitation of diagnosis horizons and diagnostic characteristics, on this basis, to identify the rich soil types in our country and set up a new complete with retrieval system of spectrum type soil classification system, realizes our country soil classification across from qualitative to quantitative. Soil quality evaluation system is based on study of the distribution of soil series, according to certain principles, methods and standards for qualitatively and quantitatively evaluating the quality and the level of soil series merits. The purpose of the evaluation is to enhance and improve soil environment quality, and provide countermeasures and measures of improvement for production performance improvement and practice of soil series.In this paper, Chinese Soil Taxonomy as a guide, Xianning city of southeastern Hubei selected as the study area. Through the investigation of climate, vegetation, topography, land use conditions and other factors in Xianning, considerdifferent soil parent material and the distribution of different soil types to set number and locations of cross-section points. In the eco-circumstances haman district, Chibi city, Jiayu county, Tongchen county, Chongyang county were surveyed main profile, check the cross-sections of57, and promptly recorded a cross-sectional sample of soil conditions and the cross-section morphology,as well as completed stratified soil sampling work, for each section of soil samples obtained from various soil pH, calcium carbonate, organic matter, total nitrogen, total phosphorus, total potassium,22physical and chemical properties analysis indicators such as bulk density were measured.Based on the Chinese soil taxonomic classification, the30typical single soils were selected as the study objects, according to the requirements of quantitative classification index from the Chinese Soil Taxonomy (third edition) and combined with the soil profile diagnosis horizons and diagnostic characteristics to differentiate the senior taxa belonging of all samples. According to the Chinese soil classification standards of soil families and series, will be30typical single soils are divided into twenty-five kinds of soil families, the final merged of soil series are divided into29kinds and finally use soil series as evaluation unit to evaluate sample region soil quality, the main results are as follows: (1)"Chinese Soil Taxonomy (third edition)" as the basis, combined with the diagnostic horizons and characteristics of each cross-sections, in accordance with the order to retrieve soil type detection in a retrieval system, differentiate30samples of Xianning sample region to senior soil taxa belonging, including five kinds of classes (artificial soil, leaching the soil, cambosols, iron-rich soil, new soil into soil),six kinds of subclasses (hydroponic artificial soil, leaching the soil moist, humid cambosols,ect.), eleven kinds of types (iron poly hydroponic artificial soil, calcareous soil moist prototype, Jane sterile moist soil,ect.),fifteen kinds of sub-categories (ordinary Jane PADDY soil, Ordinary iron moist cambosols, ordinary perturbation siltationnew soil,ect.).(2)According to the Chinese classification standards of soil family and soil series, on the basis of sub categories, according to the samples of particle size, mineralogical composition, soil temperature conditions, calcareous and acid-base reaction were divided into25soil families; and used specific soil depth and thickness, surface soil texture, soil rock debris, tuberculosis, and other intrusions as divided indicators of the soil series, classifying and merging the soil series in the same soil family, finally approved for tentative soil series were divided into29.(3)Based on the analysis of the soil series and soil database has been established, the soil series are the basic evaluation units to determine soil quality evaluation indexes weights using principal component analysis (PCA), and according to the calculated standardized values and weights of each indicator are calculated for each comprehensive evaluation indexes of soil samples.The higher the index value, the better the quality of soil series, the lower the index value, the worse the quality of the soil series. According to the results of each indexes of soil series of29divided by soil quality to do the analysis and evaluation showed the evaluation results and actual field investigation have high consistency and using PCA on the objective assessment of soil series have a certain feasibility.