Spatial Distribution of Soil Properties and Evaluation of Fertility Quality of Yellow River Floodplains in Yinchuan City
To elucidate the spatial distribution characteristics of soil properties in the Yellow River floodplains in Yinchuan and to analyze the differences in soil properties among different land use types,92 soil samples were collected from the cultivated layers by homogeneous sampling,soil properties included bulk density,porosity,field water capacity,pH,electrical conductivity,salinity,organic matter,total nitrogen,total phosphorus,total potassium,available nitrogen,available phosphorus,available potassium,nitrate nitrogen and ammonium nitrogen were determined and their spatial distribution characteristics were discussed,meanwhile soil fertility quality were also comprehensively evaluated by geostatistics and fuzzy mathematical methods.The results showed that soil bulk weight was of 1.07-1.52 g/cm3,field water capacity of 18.18％-31.16％,total porosity of 33.60％-49.83％,capillary porosity of 26.67％-36.43％,and non-capillary porosity of 5.6％-17.00％;soils were alkaline and with low nitrogen and phosphorus contents.Forest land had the best soil physical characteristics,the pH of the abandoned land was significantly higher than that of the cropland(P＜0.05),electrical conductivity,salinity and ammonium nitrogen were significantly higher in the fallow land than in the other three land types(P＜0.05),total phosphorus significantly lower in forest land than in the other three land types(P＜0.05),and available phosphorus significantly higher in cropland and abandoned land than in forest and wasteland(P＜0.05),while the other physicochemical properties were not significantly different among different land use types.The overall spatial distribution of field water capacity,total porosity and non-capillary porosity were larger upstream and smaller downstream,but opposite for bulk density,pH,electrical conductivity,salinity and available phosphorus,meanwhile the spatial distribution of the other physicochemical properties were irregular.The average value of soil integrated fertility index(IFI)was from the middle to the lower levels.Soil pH and inorganic nitrogen were the factors dominating soil quality indicating soil fertility can be improved mainly by improving pH and nitrogen content.
Yellow River floodplainSoil physiochemical propertiesSoil fertility evaluationSpatial distribution
万方数据
维普
