| Soil nutrients is the basis of crop growth.In recent years, with the increasing use of agricultural fertilizer and pesticide in agriculture in order to increase soil nutrient contents, and the soil pollution caused by excessive fertilization has drawn more and more attention. The method of spatial variability is the prerequisite and basis for analysis of the distribution of soil nutrients implement precision agriculture and prevent soil pollution.Zhangjiakou grape-producing areas which is well known for producing high-quality fruit, the analysis of the contents and spatial variability of soil nutrients and polluting elements in order to adjusting fertilizer application structure, prevent the loss of nutrient.The study even analyze the extent of soil pollution and which impact on fruit quality, and it provided a theoretical basis to divide high-quality fruit production area and prevent soil pollution. Which have great significance in sustained and healthy development of Zhangjiakou grape-producing areas.The method of GIS and statistical were used to study the patial variability of soil nutrients and polluting elements in Zhuolu and Huailai counties in Zhangjiakou province, while the use of single factor index method, the composite index as well as the potential ecological risk index method were used in order to assess soil environmental quality and potential ecological risk of fruit-producing areas, while the contents of antibiotics in the three counties were analyed, the main results as follows:1 The result of Basic statistical of soil elements as follows:(1) The coefficient variation of K2O was less than 10%, which had a low variability; the coefficients of variation of N,P,organic matter,Cd,As,Cr,Pb were ranging from 10% to 100%, which had moderate variation, whereas coefficient variation of Hg is greater than 100%, which had a strong variability.(2) Among the indicators of soil fertility, pH had a significant negative correlation with constant element N,P and polluting heavy metals Pb,Cd,Hg. Other elements in the soil which had no significant correlation with pH may influenced by other factors. OM had a significant positive correlation.with Constant element N,P, micro -nutrient elements Zn,Mn,Cu,B,and soil pollution of heavy metals Pb,Cd, As,Hg,Cr.(3) The analysis of histogram shows that: nutrient elements N,P,K2O,Zn,Mn, Cu, OM had log-normal distribution; among micro-nutrient elements, Fe2O3,B had normal distribution; among polluting heavy metals,As,Cr had normal distribution, Cd, Hg had log-normal distribution.2 The analysis of the spatial variability of soil elements with the method of GIS and statistical as follows:(1) Through the determined by fitting the model, N was the exponential model; K,OM,Cu,Mn,Zn,As,Cr was the spherical model; P,Fe2O3,B,Pb,Cd,Hg was the Gaussian model. The nugget constant of K2O,Fe2O3 were 23.08%, less than 25%, which showed that this two elements have a high spatial correlation and less affected by external factors, this mainly caused by some internal factors such as soil parent material, topography, soil type, climate and other factors; the nugget constant of N,P,OM,Cu,Zn,B,Mn,As,Cr,Hg were more than 25% and less than 75%, this four elements all have moderate variability, which mainly caused by the influence of external random factors such as a large extent by the fertilizer, irrigation and other management level, while the nugget constants of Pb,Cd were 25 % and 75%, which showed that spatial correlation of Pb between weak and middle-spatial correlation and Cd between the medium and strong spatial.(2) Kriging interpolation showed that: there is a significant regional distribution characteristics in the spatial distribution of elements in soils, in which N,P,OM,Cu,Zn,B,Mn,As,Cr,Hg,Pb,Cd,Fe2O3 showed a decreasing trend from west to east, K2O showed a gradual increase trendfrom west to east. In addition to K2O, the distribution of other study elements in Zhuolu County were higher than which in Huailai County .3 Soil environmental quality and the assess of potential ecological risk as follows:(1) Single-factor pollution index Pi of Zhuolu, Huailai, Xuanhua grape sampling area were less than 1, the comprehensive pollution index showed Huailai County CIP> ENR> LOM; which of tetracycline antibiotics were OTC> CTC> TC > DC. The average concentration of NOR was the highest in all antibiotics for 33.15μg/kg, while the content of LOM was minimum in all antibiotics for 0.49μg/kg. pH had a very significant negative correlation with NOR,CIP,OTC,TC. OM had a very significant positive correlation with OTC,TC,NOR,CIP.(3) When the potential parameters of Eir <40,which means a low level of risk; when the potential risk parameters RI <150, which means the over all low degree of potential risk.single factor Ei of ecological risk factor in Zhuolu,Huailai,xuanhua showed that: the five elements of Ei is less than 40 in the three cunties,which had a low degree of hazard levels. The order of comprehensive potential risk in three countieswere Xuanhua >Zhuolu >Huailai, RI are less than 150, which had a low degree of hazard levels.
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