Evaluation Of Soil Suitability On Green Fruit Production In The Main Pear Areas Of Hebei Province

People's demand for non-polluting, safe, healthy green food is growing as the living standards improved. The development of greed food is an important way to enhance our economy, and become an international trend. This paper has zoned four green pear growing areas in Xinji, Zhaoxian, Boutou, Xianxian via evaluating the heavy metal content in soil and fruit quality. The main results are as follows:1,By comparing the average content of soil heavy metals in study area and the background values in Hebei and the nation, the total content of four main heavy metal (Zn,Pb,Hg,Cr,Ni,As) is below the value of Hebei and the nation. But the content of the Cu and Cd is beyond the value in some sample points.2,The paper made an assessment of the soil quality to eight kinds of heave metal based on the soil environmental quality standards, environmental standards of green food production and the soil quality standards for pollution-free green food. And draw a result figure by GIS combined with the agro-ecological geochemical survey. The results shows that the soil in the study areas are all in a high quality and suitable for greed food production.3,The paper chooses the fruit weight as the appearance evaluation factors, and the soluble solids, total sugar, titratable acid, Vc and sugar acid ratio as the internal quality evaluation factor. Via the chromatography analysis and variation coefficient analysis, the paper get the contribution rate of the pear fruit quality indicators tothe quality, descending as total sugar> titratable acid> soluble solids> sugar to acid ratio of> fruit weight> Vc.4,Based on 49 typical samples, the paper analyses the relevance of pear fruit quality indicators and the mineral elements, the relation of pear fruit quality indicators and the elements in different levels of soil, and compared the soil element content in high quality and low quality, finally made the selection of elements which mostly contributed to the pear quality: Se,As,Cu,B.5,The paper has made the principles of optimizing layout for high-quality pear production base on the pear geological and geochemical environment factors. There are 1261.42km~2 areas suitable for pear planting accounted for the total study area of 27.56%, which is the optimal region for level A pear planting. There are 655.48m~2 areas suitable for pear planting accounted for the total study area of 12.21%, which is the optimal region for level AA pear planting. This paper is part of the Hebei Province Geological Projects. The results and the research method is of great importance to guiding the agricultural structure adjustment and planning the development of green A/AA class pear-growing areas rationally, has an important meaning to food safety.