| To address the reason why the number and the density of crofton weed in the soils of pine forests are bigger
than those in the Cyclobalanopsis trees under the same environment, the contents of total nitrogen, ammonium nitrogen,
total phosphorus, available phosphorus, total potassium and available potassium in the two soils samples are investigated.
The results show that the contents of soil total nitrogen, available phosphorus and available potassium in the soils from
Cyclobalanopsis trees are higher than those from the pine forests, whereas the contents of soil total phosphorus, total
potassium of the former are lower than those of the latter. There is no difference of the ammonium nitrogen content between them. The possible reason for the differences in the number and the density of crofton weed between these two types of soils is that the differences in the contents of total phosphorus and total potassium. Specifically, high contents of total phosphorus and total potassium in the pine forests soils would promote population density and invasion of crofton weed and are more suitable for the growth of crofton weed. |
