| Hebei Province have the advantage position near Beijing and Tianjin soil quality should be controlled, to protect soil environment in order to avoid infraction, prevent soil deterioration in qualityfor producing no pollution, and green vegetables,in order to meet the quality of life of the demand and increase farmers' income.In this paper, 17 soil fertility evaluation indexes were selected from the primary 25 factors using principal component analysis, by sampling and laboratory analysis to soil and vegetables in typical vegetable-based of Hebei Plain. And the weights were determined by analytic hierarchy process. Quality and heavy metal contamination of soil fertility status were evaluated using fuzzy mathematics method, and the impact of the soil environment quality for vegetables pollution was descripted .1 Classification in accordance with the relevant standards of soil fertility, vegetable area measuring soil organic matter, total nitrogen, available molybdenum reached the fourth level of land fertility. Available K, available Fe, available Mn, available B and available S, reached the third level. Available phosphorus, exchangeable calcium achieve to the first level. Soil nutrient content was more abundant, requirements in line with the growth of vegetables.2 The total heavy metals were evaluated in survey area adoption of " Safety qualification for agricultural product-Environmental requirements for origin of non-environmental pollution vegetable" (GB184071-2001) and " Environmental technical terms for green food production area " (NY/T391-2000) as the standard, Evaluation of single indicator value was less than 1. Evaluation of composite indicator value was less than 0.7. The soil were safe and clean, suitable as a pollution-free or green vegetable production base. The heavy metal contents of vegetables did not exceed the limited standard in "Safety qualification for agricultural product——Safety requirements for non-environmental pollution vegetable" (GB18406.1-2001). They were non-environmental pollution vegetables.3 The study area soil total heavy metals average concentration did not exceed pollution-free or green vegetables of Environmental standards in place, suitable for the development of pollution-free or green vegetable base. However, in some areas of soil total content of chromium and cadmium were close to the standard of green food production limited to the vicinity of the cordon, in the selection of green products in these areas to monitor the soil base chromium and cadmium to prevent the excessive heavy metal.4 In this paper, 17 evaluation indexes with the Hebei Plain vegetable related were selected from the primary 25 factors using principal component analysis. And the weights were determined by analytic hierarchy process. The soil quality was evaluated comprehensively in study area to determine the fertility level of vegetable soil. Soil fertility mainly were the fifth level in Dingzhou City and Yongnian County, Fengnan District, Yongqing County soil fertility mainly in the third level.5 The contents of soil organic matter and available K were less in Dingzhou City of central Hebei and Yongnian County of southern Hebei. Soil organic matter average contents were 12.45g/kg and 12.72g/kg; and soil available K average contents were 91.04 mg/kg and 118.63 mg/kg. Organic manure and potash fertilizer should be increased to increase soil organic matter and available K contents and lower soil bulk density and improve the quality of vegetables. Total salt content in soil were higher in Fengnan of Coastal Plain and Yongqing County of around Beijing and Tianjin. Organic fertilizer should be based, and fertilizer usage should be control, to prevent increasing the degree of soil salinization.
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