Study on the Activation of Trace Nutrient Elements in Soil by Freeze-thaw Action

摘要

In order to explore the mechanism of action that the freezing-thawing cycle times and freezing temperature to the nutrient forms and enzyme activity of zonal soil(Lou soil,feldspathic sandstone),using indoor freezer to simulate different freezing temperature(20 °C intense frozen and-10 °C weak frozen),with different freezing and thawing cycles(onece and twice).The results shows that the total nitrogen content of the two samples of the freeze-thaw cycle increases,and the increment trend of feldspathic sandstone is more pronounced than Lou soil’s;The increase of potassium content in Lou soil and feldspathic sandstone is 4.7% and 5.3% respectively compared with that before frozen.The effective phosphorus content of 2 kinds of soil in freezing-thawing cycle decreases,and the reducing trend of Lou soil is more pornounced than feldspathic sandstone’s.The peroxidase activity was enhanced by freezing-thawing cycle;however,the activity of urease was decreased.The effect of freezing temperature on the active nutrient and enzyme activity of tillage soil is not significant.