Effect Of Tea Root Secretion On The Trasformation Mechanism Of Phosphorus And Aluminum Forms In The Soil

Tea plant is a typical aluminum acidophilous plant. The phosphorus in the soil is easy to be fixed in the acidic condition. The mechanism of interact between P and Al in the tea garden soil is not very clear at present. To get process and mechanism of interaction between Phosphorus and Aluminum in the tea garden soil,the experiement study the process of Phosphorus and Aluminum'forms information in soil with the action of root secretion from tea plant. Change of the Phosphorus and Aluminum' forms,which in the quaternary red clay and red mud and sand evolved from weathered residual granite, were affected by root secretion from tea plant. The main results were as follows:1 The experiment form transformation of Phosphorus show that the four different forms of phosphorus in the soil that added root secretion changed significantly and it is almost no change which soil for hydroponics. In the former, the concentration of A1-P and O-P is increasing, while the Fe-P and Ca-P concent is reduction. The rusult show that the root secretion influence the form transformation of Phosphorus in the soil.2 The result of soil phosphorus form transformation cultivation experiment showed the as the change over time,concentration of the different form of Phosphorus have various change trends. The concentration of Al-P in the soil decreases over time,while the concentration of Fe-P in the soil increase over time, the result show that the Al-P in the soil translate into the other forms of phosphorus, but the other forms of phosphorus translate into Fe-P.the concentration of Ca-P and O-P had little change. This shows that it is relatively stable in the soil is rich of root secretion.3 The result of soil aluminum transformation cultivation experiment showed that The transformation mechanism of The aluminum speciation were were changed with different cultivate time. The Al-Humic in the soil increase gradually with the increase of the cultured time, making other aluminum species forms to the Al-humic conversion. By comparing the rate of change of four different forms of aluminum species, it is observed that Aluminum morphology transformation direction is not fixed,Aluminum inorganic absorption transform to other Aluminum species firstly, then other Aluminum species transform to Aluminum inorganic absorption when it reached a tipping point.