外来树种马占相思自然繁殖更新研究  

Study on Natural Regeneration of Exotic Acacia mangium

作　　者：宗亦臣[1] 郑勇奇[1] 张川红[1] 刘宁[1] 

机构地区：[1]中国林业科学研究院林业研究所

出　　处：《林业科学》2006年第7期16-20,共5页Scientia Silvae Sinicae

基　　金：国家科技部重点项目"外来树种入侵性及生态风险评价"(2002DIB50122)。

摘　　要：调查马占相思人工林的自然更新情况,在国内首次发现马占相思存在种子成苗方式的自然更新。但马占相思的自然更新受立地条件制约:只有在林缘的裸露立地条件下,马占相思的种子才能萌发成苗。马占相思16年生单株在45°扇形单方向更新扩散的最远距离为17.5m,更新繁殖的株数最多有26株;扩散距离与扩散株数之间没有明显的相关性。1987年穴状埋根造林的马占相思,其林缘更新扩散的最远距离为10.0m,更新繁殖的株数最多有3株;1997年穴状埋根造林的马占相思,其林缘更新扩散的最远距离为3.0m,更新繁殖的株数最多有14株。用小样方法调查马占相思人工林下乡土乔木、灌木和草本植物的自然更新。结果表明,在马占相思林分内,共发现12种乔木树种、3种灌木树种和8种草本植物,这些乡土植物均表现为生活力强。研究结果表明,马占相思在靠近水源的裸露立地条件下可以自然更新,更新的方式为种子繁殖;马占相思不影响乡土植物的正常生长。Acacia mangium is a typical and important exotic tree species for short-rotation industrial plantation in south China. It was found that the species could naturally regenerate from seed at appropriate site conditions. The seed of A. mangiam in plantations could germinate only in open areas in stand edge. The longest dispersal distance of a single-tree at age of 16 years was 17.5 m and the largest number of regenerated trees was 26 in a 45° sector area around the tree. The distance of single-tree dispersal was not closely related to the number of regenerated trees. The longest distance of dispersal from stand edge of A. mangium was 10.0 m, which were planted with roots buried in hole in 1987, and the largest number of regenerated trees was 3. The longest distance of dispersal from stand edge of A. martgium was 3.0 m for the other stand planted in 1997, and the largest number of regenerated trees was 14. The effects on natural regeneration of native trees, shrubs and herbaceous plants under the A. mangium plantation were surveyed by setting sub-plots within the sample plots. 12 native tree species, 3 shrub species and 8 herbaceous plants species were found. They all have strong viability under the A. mangium canopy. Results indicated that A. mangium can naturally regenerate from seeds and establish itself in open areas in the stands. No significant impact on native tree species and other vegetation was found, indicating that the risk of bioinvasion of A. mangium is low.

关 键 词：外来树种 马占相思 自然更新 

分 类 号：S754.1[农业科学—森林经理学]