A study on sampling different state of soil water and their characters of chemical compositions

Sampling duration for soil water at different state was studied using centrifugation,with analytic determination of their chemical compositions.The results presented the time needed for extracting soil water at different PF segment and the contents of main ions and composition characters of the extracted soil solutions.This work is helpful to researches on crop growth and nutrient cycle in soil-crop ecosystem,soil fertilization and so on.