Abstract: In the background of large scale rubber planting,in order to probe into the changes of rubber trees across the life course and distribution of soil nutrients,the method of space for time was used for the analysis and research on 8 different segments of the rubber plantation soil nutrients in the farm.The results show that(1)The organic matter content of the surface soil(0～20cm)was significantly higher than that in 20～40cm soil layer.With the age increasing,organic matter content showed a trend that decreased at first and then increased.The organic matter content of the soil at different ages from high to low in order of the secondary forest(CK)>5a>10a> 35a>20a>40a>25a>30a>15a.Statistical analysis showed that the organic matter in the soil layer of 0～20cm and total nitrogen was significantly correlated(R=0.78130),In the 20～40cm soil layer,there was a very significant positive correlation with the total nitrogen(R=0.91811),and significantly with the total phosphorus(R=0.77249).(2)The total nitrogen content of the surface soil(0～20cm)was significantly higher than that of the lower,the content of total nitrogen in surface soil increased slowly with the increase of age,20～40cm soil layer decreased at first and then increased with the increase of age.The total nitrogen content of soil is in the order of the secondary forest(CK)>5a>10a>35a>40a>30a>25a>20a>15a.(3)The total phosphorus content in the soil decreased with soil depth.With the change of tree ages the trend of total phosphorus content in the soil was the same as organic matter content.The total phosphorus contents in soil at different ages showed such a from-high-to-low ordes as 5a>10a>secondary forest>35a(40a)>20a>25a>15a(30a).(4)The content of total potassium had no significant change in the soil profile, but gradually decreases with increase of age. The average content of total potassium in the soil was in the order of 35a>10a>5a>25a>30a>secondary forest (CK)>20a>40a>15a. This is mainly due to the growth characteristics of rubber tree, soil texture and the difference of artificial fertilization management and so on. Through the experiment, expect to be able to understand the demand on nutrient of rubber tree at different ages, and the dynamic changes of nutrient elements in the soil, to provide a theoretical reference for the guidance of scientific production and fertilization management of plastic agricultural.

Key words: rubber plantation, tree ages, soil nutrient, soil layer