This paper is the result of agricultural geochemical survey engineering.[Objective]The research aimed to provide a scientific basis for the rational use of soil nutrients in agricultural production, adjustment of agricultural structure and improvement of land use value in Renhuai.[Methods]Total and available nitrogen (phosphorus and potassium) content and organic matter content of 5,486 topsoil samples were obtained using inductively coupled plasma emission spectrometry, volumetric method, and potentiometric method. Their geochemical characteristics and influencing factors were systematically studied.[Results]The average values of nitrogen, phosphorus, potassium, organic matter, available nitrogen, rapidly available phosphorus, and rapidly available potassium were 1.74 g/kg, 0.75 g/kg, 19.90 g/kg, 30.90 g/kg, 100.28 mg/kg, 10.40 mg/kg, and 101.03 mg/kg, respectively. The contents and distributions of nitrogen, available nitrogen, phosphorus, potassium, and organic matter were closely related to the stratum, whereas those of rapidly available phosphorus and rapidly available potassium were not. Cultivated land in Renhuai had a relatively high soil fertility rating, which was mainly dominated by relatively rich soil grades, with the share of relatively rich and rich grades reaching 57.6%. Rich nitrogen, phosphorus, and potassium levels were found, along with medium available nitrogen and organic matter levels. However, rapidly available phosphorus and rapidly available potassium were at deficient levels.[Conclusions]The content and distribution of soil nutrients in cultivated land are not only affected by natural factors such as geological background, soil type, altitude, pH, and soil depth, but also related to human activities, such as land use patterns.
Highlights: Total and available nitrogen (phosphorus and potassium) content and organic matter content in cultivated soil in Renhuai were systematically calculated, their geochemical grades were evaluated, and the influencing factors of their contents were systematically analyzed. The content and distribution of soil nutrients in cultivated land were not only affected by natural factors, such as geological background and soil type, but also related to human activities, such as land use patterns.