海南岛木麻黄林林下植物天然更新影响因素的研究.

Casuarina equisetifolia coastal protection forest(C. CPF)is an important barrier of coastal ecology in Hainan Island, and natural regeneration is of great significance for it to play a role of protection function continuously. It is found that undergrowth natural regeneration is difficult in the most area of C. equisetifolia forests in Hainan Island, however, there is a phenomenon of good regeneration in the local area. In order to explore the cause of the great disparity in the natural regeneration, and to provide certain theoretical basis for promoting the transformation of C. CPF from plantation to near-natural forest, the main factors affecting the natural regeneration of C. CPF were studied through the analysis of the differences of regeneration quality for different forest lands. Seventy-three temporary plots were established in the C. CPF in Hainan Island, and statistical methods, such as variance analysis and correlation analysis, were used to study the effects of climate zones, stand conditions, soil factors and litter accumulation on natural regeneration quality and density. The results were as follows:(1)The regeneration of C. CPF in wet zone was significantly better than that in dry zone;(2)There was significantly negative correlation between C. equisetifolia stand density and regeneration density or herb coverage, but other factors of stand conditions had little effect on regeneration;(3)There was no significant diffe-rences in soil pH value and nutrients in the sample plots with different regeneration qualities, but ammonium nitrogen promoted the regeneration of seedlings and organic matter did the regeneration of saplings to some extent;(4)The accumulation of litter was not conductive to natural regeneration as a whole. The results indicate that the climate factor, density of C. equisetifolia stands and accumulation quantity of C. equisetifolia litters were the main impact factors for the natural regeneration of undergrowth in C. CPF. [ABSTRACT FROM AUTHOR]