[Seedling regeneration and spatial correlation between seedlings and seed trees in Castanopsis hystrix plantation by large diameter wood cultivation in south subtropical China].

Using the paired correlation equation g(r) in the spatial point patterns, we investigated the regeneration characteristics and spatial patterns of Castanopsis hystrix seedlings and the spatial correlation with the seed trees in the plantation by large diameter wood cultivation in south subtropical China. The results showed that natural seedling regeneration in C. hystrix plantation was good, which were widely distributed in the whole plantation.

[Soil physical and chemical characteristics under different vegetation restoration patterns in China south subtropical area].

This paper studied the change of soil physical and chemical properties under eleven vegetation restoration patterns (1 kind of secondary forest, 2 kinds of pure coniferous plantations, 5 kinds of evergreen broad-leaved plantations, 2 kinds of conifer and broad-leaved mixed plantations, and 1 kind of shrub) typical in Daqingshan of Guangxi. Obvious differences were observed in the soil physical and chemical properties under different vegetation restoration patterns. The soil physical properties were better in secondary forest but poorer in pure conifer plantations.

[Effects of Pinus massoniana plantation stand density on understory vegetation and soil properties].

By using plot investigation and sampling analysis methods, the understory vegetation and soil properties of Pinus massoniana plantations with different stand density in subtropical area were studied in Daqingshan, Guangxi Province. In the P. massoniana plantations after 14-year natural growth, the understory species diversity index of shrub layer increased with the increase of stand density from 1050 trees x hm(-2) to 1800 trees x hm(-2), but decreased when the stand density further increased to 2250 trees x hm(-2).